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Patent 2726604 Summary

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Claims and Abstract availability

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(12) Patent: (11) CA 2726604
(54) English Title: VENTILATOR APPARATUS AND SYSTEM FOR VENTILATION
(54) French Title: VENTILATEUR ET SYSTEME DE VENTILATION
Status: Granted
Bibliographic Data
(51) International Patent Classification (IPC):
  • A61M 16/00 (2006.01)
(72) Inventors :
  • HABASHI, NADER, M. (United States of America)
(73) Owners :
  • HABASHI, NADER M. (United States of America)
(71) Applicants :
  • INTENSIVE CARE ON-LINE NETWORK, INC. (United States of America)
(74) Agent: RIDOUT & MAYBEE LLP
(74) Associate agent:
(45) Issued: 2023-09-12
(86) PCT Filing Date: 2008-06-02
(87) Open to Public Inspection: 2008-12-04
Examination requested: 2013-05-17
Availability of licence: N/A
(25) Language of filing: English

Patent Cooperation Treaty (PCT): Yes
(86) PCT Filing Number: PCT/US2008/065592
(87) International Publication Number: WO2008/148134
(85) National Entry: 2010-12-01

(30) Application Priority Data:
Application No. Country/Territory Date
60/924,835 United States of America 2007-06-01

Abstracts

English Abstract


A ventilator (10) for use by a clinician in supporting a patient presenting
pulmonary
distress. A controller module (20) with a touch-screen display (26) operates a
positive or
negative pressure gas source (40) that communicates with the intubated or
negative
pressure configured patient through valved (46) supply and exhaust ports (42,
44). A
variety of peripheral, central, and or supply/exhaust port positioned sensors
(54) may be
included to measure pressure, volumetric flow rate, gas concentration,
transducer, and
chest wall breathing work. Innovative modules and routines (30) are
incorporated into
the controller module enabling hybrid, self-adjusting ventilation protocols
and models
that are compatible with nearly every conceivable known, contemplated, and
prospective technique, and which establish rigorous controls configured to
rapidly adapt
to even small patient responses with great precision so as to maximize
ventilation and
recruitment while minimizing risks of injury, atelectasis, and prolonged
ventilator days.


French Abstract

L'invention concerne un ventilateur (10) devant être utilisé par un médecin pour aider un patient en détresse pulmonaire. Un module d'unité de commande (20) avec un écran tactile (26) actionne une source de gaz de pression positive ou négative (40) qui communique avec le patient configuré à pression négative ou intubé par des orifices d'alimentation et d'évacuation (42, 44) à soupape (46). Une variété de capteurs positionnés sur les orifices d'alimentation/évacuation, périphériques, centraux (54) peut être incluse pour mesurer la pression, le débit volumétrique, la concentration en gaz, le transducteur et le travail de respiration des parois de la poitrine. Des modules et sous-programmes innovants (30) sont incorporés dans le module d'unité de commande permettant des protocoles et modèles de ventilation hybrides à autoréglage qui sont compatibles avec presque chaque technique connue, envisagée et possible, et qui établissent des commandes rigoureuses configurées pour s'adapter rapidement aux réponses de patient même lorsque lesdites réponses sont petites avec une grande précision de sorte à maximiser la ventilation et le recrutement tout en rendant minimaux les risques de lésion, d'atélectasie et de jours de ventilation prolongée.

Claims

Note: Claims are shown in the official language in which they were submitted.


WHAT IS CLAIMED IS:
1. A ventilator system for assisting in respiratory function of a patient
under
direction of a clinician, comprising:
a supply pump and a control module in communication with a data circuit and a
gas circuit having a plurality of valves and supply and exhaust ports, the
control
module including a display, input device, and a memory in communication with
the
data circuit;
a sensor array in communication with the data circuit that includes at least
one
oximeter, at least one capnometer, at least one pressure sensor, and at least
one flow
meter in communication with at least one of the supply and exhaust ports for
measuring a patient actual data array element including at least one of (i) a
patient
SpO2 quantity, (ii) a patient etCO2 quantity, (iii) a peak expiratory flow
rate, (iv) an end
inspiratory lung volume, (v) an end expiratory lung volume, or (vi) a
spontaneous
breathing frequency;
at least one initialization parameter database resident in the memory
communicable with the display and configured to store at least one model
patient data
array element that includes at least an FiO2 quantity, a high pressure, a low
pressure, a
high time, and a low time; and
a command module resident in the memory operative to command the control
module to adjustably actuate the supply pump or the plurality of valves to
establish a
pressure, volume, or flow rate in the gas circuit;
wherein the command module comprises an initial setup module with an optimal
end expiratory lung volume assessment mode configured to ascertain an optimal
end
expiratory lung volume from a patient actual data array, and an adjustment and

maintenance module with an oxygenation mode, and a ventilation mode, and a
weaning
module having a weaning mode,
wherein the command module is configured to automatically perform a feedback
loop from the sensor array to automatically perform a programmed order that
includes,
in order, the optimal end expiratory lung volume assessment mode, the
oxygenation
mode, the ventilation mode, and the weaning mode,
44
Date Recue/Date Received 2022-06-30

wherein the command module is configured to determine when one mode is
completed and automatically proceed to a next mode in the programmed order,
wherein the command module is configured to determine when one mode is to
proceed to an earlier mode in the programmed order, and automatically proceed
to the
earlier mode,
and
wherein the command module is configured to compare the patient actual data
array to at least one model patient data array, and to automatically adjust
the supply
pump or the plurality of valves to adjust the pressure, the volume or the flow
rate to
achieve an SpO2 goal value, an etCO2 goal value, the optimal end expiratory
lung
volume and an optimal end inspiratory lung volume.
2. The ventilator system according to claim 1, wherein the adjustment and
maintenance is further configured to implement a recruitment mode.
3. The ventilator system according to claim 1, wherein the weaning mode of
the
weaning module includes an initial weaning mode, an airway pressure release
ventilation mode, and a continuous airway pressure or CPAP mode.
4. The ventilator system according to claim 1, wherein the at least one
model
patient data array element further includes at least one of a positive end
expiratory
pressure, an SpO2 quantity, an etCO2 quantity, a pressure increment, a time
increment,
a tidal volume, a machine respiratory frequency, a pressure-volume slope, a
trigger
pressure, or occlusion pressure.
5. The ventilator system according to Claim 1, wherein if the SpO2 goal
value is
false, the command module is configured to communicate with the sensor array
and
ascertains the patient actual data array to ascertain a patient FiO2 quantity
and
determine an FiO2 goal value; and
wherein if the FiO2 goal value (a) is true, the command module is configured
to
communicate with the sensor array and ascertains the patient actual data array
to
Date Recue/Date Received 2022-06-30

ascertain the high pressure, and if the high pressure (i) is false, the
command module is
configured to command the control module to adjust at least one of the supply
pump or
the plurality of valves to increase the high pressure by at least one pressure
increment
and to increase the high time by at least one time increment, and sets the
optimal end
expiratory lung volume to be true, and (ii) is true, the command module is
configured to
set a recruitment value to be true, and (b) is false, the command module is
configured to
command the control module to adjust at least one of the supply pump or the
plurality of
valves to increase the Fi02 quantity.
6. The ventilator system according to Claim 1, wherein if the SpO2 goal
value is
true, the command module is configured to communicate with the sensor array
and
ascertains the patient actual data array to ascertain a patient Fi02 quantity
and
ascertains the patient actual data array to ascertain a patient FiO2 quantity
and
determine an FiO2 goal value; and
wherein if the FiO2 goal value (a) is true, the command module is configured
to
command the control module to adjust at least one of the supply pump or the
plurality of
valves to decrease the Fi02 quantity and (b) is false, the command module is
configured to set a ventilation value to be true.
7. The ventilator system according to Claim 1, wherein the command module
is
configured to communicate with the sensor array and ascertains the patient
actual data
array to compute a recruitment value; and
wherein if the recruitment value (a) is true, the command module is configured

to generate a clinician alarm signal, and, (b) is false, the command module is

configured to command the control module to adjust at least one of the supply
pump
or the plurality of valves to increase the high pressure by at least one
pressure
increment, increase the high time by at least one time increment, and adjust
the low
time by at least another time increment, and ascertains the SpO2 goal value,
and if
the SpO2 goal value (i) is true, the command module is configured to set an
oxygenation value to be true, and (ii) is false, the command module is
configured to
set the recruitment value to be true.
46
Date Recue/Date Received 2022-06-30

8. The ventilator system according to Claim 1, wherein the command module
communicates with the sensor array and ascertains the patient actual data
array to
measure a peak expiratory flow rate, measure a truncation of gas flow, compute
an
angle of deceleration of gas flow, determine the optimal end expiratory lung
volume,
and ascertain a lung condition; and
wherein if the lung condition (a) is true, the command module polls the sensor

array to measure a patient PaCO2 quantity, adjusts the low time to achieve an
optimal
end expiratory lung volume of 25-60%, and sets an oxygenation value to be
true, and
(b) is false, the command module polls the sensor array to measure the patient
PaCO2
quantity, adjusts the low time to achieve an optimal end expiratory lung
volume of 50-
85%, and sets an oxygenation value to be true.
9. The ventilator system according to Claim 4, wherein if the etCO2 goal
value, a
comparison between the spontaneous breathing frequency and the machine
respiratory
frequency and the high time is false, the command module is configured to
determine
the high pressure; and
wherein if the high pressure (a) is false, the command module is configured to

command the control module to adjust at least one of the supply pump or the
plurality of valves to increase the high time by at least one time increment
and
increase the high pressure by at least one pressure increment and (b) is true,
the
command module is configured to command the control module to adjust at least
one of the supply pump or the plurality of valves to increase the high time by
at least
one time increment.
10. The ventilator system according to Claim 4, wherein if the etCO2 goal
value is
false, a comparison between the spontaneous breathing frequency and the
machine
respiratory frequency is true and the high time is true, the command module is

configured to determine the high pressure; and
wherein if the high pressure (a) is true, the command module is configured to
determine a release volume, and if the release volume (i) is false, the
command module
47
Date Recue/Date Received 2022-06-30

is configured to set a recruitment value to be true, and (ii) is true, the
command module
is configured to determine the SpO2 goal value, and (b) is false, the command
module is
configured to command the control module to adjust at least one of the supply
pump or
the plurality of valves to decrease the high time by at least one time
increment and
increase the high pressure by at least one pressure increment.
11. The ventilator system according to Claim 4, wherein if the etCO2 goal
value is
true, the command module is configured to set an initial weaning value to be
true, and
samples the spontaneous breathing frequency; and
wherein rf the spontaneous breathing frequency (a) is false, the command
module is configured to ascertain a tachypnea value that if true enables the
command
module to set a ventilation value to be true, and (b) is true, the command
module is
configured to ascertain the high pressure, and if the high pressure is false,
the
command module is configured to ascertain an apnea value and if the apnea
value (i) is
true, the command module is configured to set the ventilation value to be
true, and (ii) is
false, the command module is configured to set an airway pressure release
ventilation
value to be true.
12. The ventilator system according to Claim 1, wherein the command module
is
configured such that if the high pressure is true, the command module commands
the
control module to adjust at least one of the supply pump or the plurality of
valves to
decrease the high pressure by at least one pressure increment and to increase
the high
time by at least one time increment.
13. The ventilator system according to Claim 4, further comprising: at
least one
model patient data array further including predetermined weaning criteria that

establishes an FiO2 threshold, an SpO2 threshold, a spontaneous tidal volume,
a minute
ventilation quantity, and an airway occlusion pressure;
wherein the command module is configured to communicate with the data circuit
to sample the sensor array and measure at least one of the patient actual data
array
48
Date Recue/Date Received 2022-06-30

elements and to compare at least one of the patient actual data array elements
to the
predetermined weaning criteria to generate a weaning value; and
wherein the command module is configured such that if the command module
determines that the weaning value (a) is false, the command module commands
the
control module to adjust at least one of the supply pump or the plurality of
valves to
increase the high pressure by at least one pressure increment and to decrease
the high
time by at least one time increment, and (b) is true, the command module
repeatedly
initiate cyclic weaning by commanding the control module to adjust at least
one of the
supply pump or the plurality of valves to decrease the high pressure by at
least one
pressure increment and increase the high time by at least one time increment.
14. The ventilator system according to Claim 13, wherein the command module
is
configured such that each time the command module initiates another cyclic
weaning,
the command module ascertains the high pressure until a continuous positive
airway
pressure threshold is reached to enable the command module to set a continuous

positive airway pressure value to be true.
15. The ventilator system according to Claim 14, wherein if the continuous
positive
airway pressure value is true, the command module is configured to communicate
with
the data circuit to sample the sensor array and measure at least one of the
patient
actual data array elements and to compare the at least one of the patient
actual data
array elements to the predetermined weaning criteria to generate a weaning
value; and
wherein the command module is configured to determine the weaning value, and
if the weaning value (a) is false, the command module is configured to command
the
control module to adjust at least one of the supply pump or the plurality of
valves to
increase the continuous positive airway pressure, and (b) is true, the command
module
is configured to periodically decrease the continuous positive airway pressure
until an
extubation threshold pressure is reached.
16. The ventilator system according to Claim 15, wherein the command module
is
configured such that if the high pressure (a) is false, the command module
commands
49
Date Recue/Date Received 2022-06-30

the control module to adjust at least one of the supply pump or the plurality
of valves to
adjust the continuous positive airway pressure based on the high pressure, and
(b) is
true, the command module sets an airway pressure release ventilation to be
true.
17. The ventilator system according to Claim 10, wherein if the SpO2 goal
value (a) is
false, the command module is configured to set a recruitment value to be true,
and (b) is
true, the command module is configured to command the control module to adjust
at
least one of the supply pump or the plurality of valves to decrease the high
time by at
least one time increment.
18. A ventilator for use by a clinician in supporting a patient presenting
pulmonary
distress, comprising:
a controller including a display, input device, and a memory together in
electrical communication with a data network, the controller incorporating a
pressurized gas source in fluid communication with a gas network that includes
at
least two valves and supply and exhaust ports in communication with the
patient and
the display including a prompt for entry via the input device of at least one
of (i) an
automated initialization setting and (ii) at least one or more parameters to
be stored in
the memory that includes (a) a positive end expiratory pressure, (b) an SpO2
quantity,
(c) an etCO2 quantity, (d) an FiO2 quantity, (e) a high pressure, (f) a low
pressure, (g) a
high time, (h) a low time; (i) a pressure increment, j) a time increment, (k)
a tidal volume,
(l) a machine respiratory frequency, (m) a flow-time slope, (n) a trigger
pressure, or (o)
an occlusion pressure;
a plurality of sensors in communication with the data network that includes at

least one oxygen saturation sensor, at least one capnometer, at least one
pressure
gauge, and at least one gas flow rate meter in communication with at least one
of the
supply and exhaust ports for measuring a patient actual data array element
including (i)
a patient SpO2 quantity, (ii) a patient etCO2 quantity, (iii) a peak
expiratory flow rate, (iv)
an end inspiratory lung volume, (v) an end expiratory lung volume, or (vi) a
spontaneous
breathing frequency;
Date Recue/Date Received 2022-06-30

a command routine resident in the memory operative for driving the controller
to
adjustably actuate the pressurized gas source and at least one of the valves
to establish
a pressure, volume, or flow rate in the gas network for comparing a patient
actual data
array to the at least one or more parameters, and for computing an SpO2 goal
value, an
etCO2 goal value, and an optimal end inspiratory lung volume and an optimal
end
expiratory lung volume;
wherein the command routine is configured to automatically perform a feedback
loop from the plurality of sensors to automatically perform a programmed order
that
includes, in order, an optimal end expiratory lung volume assessment mode, an
oxygenation mode, a ventilation mode, and a weaning mode,
wherein the command routine is configured to determine when one mode is
completed and automatically proceed to a next mode in the programmed order,
wherein the command routine is configured to determine when one mode is to
proceed to an earlier mode in the programmed order, and automatically proceed
to the
earlier mode,
and
wherein the command routine is configured to compare the patient actual data
array to the at least one of the parameters, and to automatically adjust at
least one of
the valves to adjust the pressure, the volume or the flow rate to achieve the
SpO2
goal value, the etCO2 goal value, and the optimal end inspiratory and
expiratory lung
volume.
19. The ventilator according to Claim 18, wherein the command routine
communicates with the plurality of sensors and ascertains the patient actual
data array
to compute the optimal end expiratory lung volume value and ascertains a lung
condition; and
wherein if the lung condition (a) is true, the command routine polls the
plurality
of sensors to measure the patient etCO2 quantity, adjusts the low time to
achieve an
optimal end expiratory lung volume of 25-60%, and sets an oxygenation value to
be
true, and (b) is false, the command routine polls the plurality of sensors to
measure
51
Date Recue/Date Received 2022-06-30

the patient etCO2 quantity, adjust the low time to achieve an optimal
expiratory lung
volume of 50-85%, and sets an oxygenation value to be true.
20. The ventilator according to Claim 18, wherein if the etCO2 goal value
is false, a
comparison between the spontaneous breathing frequency and the machine
respiratory
frequency is false and the high time is false, the high pressure is
determined; and
wherein if the high pressure (a) is false, the command routine is configured
to
adjust at least one of the supply pump or the valves to increase at least one
of the high
time and the high pressure by at least one respective time increment and
pressure
increment and (b) is true, the command routine is configured to adjust at
least one of
the supply pump or the valves to increase the high time by at least one time
increment.
21. The ventilator according to Claim 18, wherein if the etCO2 goal value
is false, a
comparison between the spontaneous breathing frequency and the machine
respiratory
frequency is true and the high time is true, the high pressure is determined;
and
wherein if the high pressure value (a) is true and a release volume is false,
the
command routine is configured to set a recruitment value to be true, and (b)
is false, the
command routine is configured to adjust at least one of the supply pump or the
valves to
decrease the high time and increase the high pressure by at least one
respective time
increment and pressure increment.
22. The ventilator according to Claim 19, wherein the weaning mode includes
an
initial weaning mode, an airway pressure release ventilation mode, and a
continuous
airway pressure or CPAP mode.
52
Date Recue/Date Received 2022-06-30

Description

Note: Descriptions are shown in the official language in which they were submitted.


CA 02726604 2015-07-13
VENTILATOR APPARATUS AND SYSTEM FOR VENTILATION
BACKGROUND OF THE INVENTION
Field of the Invention
The invention relates to the field of ventilating human patients. More
particularly, the present invention relates to an improved ventilator and
method of
operation for ventilation intervention and initiation, oxygenation,
recruitment,
ventilation, initial weaning, airway pressure release ventilation weaning,
continuous
positive airway pressure weaning, and continuous and periodic management and
control of the ventilator.
Description of Related Art
The inventor herein has previously invented, among other inventions,
ventilator systems and methods of operation disclosed and claimed in U.S.
Patent
No. 7,246,618, and in U.S. Patent Application Publication Nos. 2008/0072901,
2006/0174884, 2003/0111078.
Airway pressure release ventilation (APRV) is a mode of ventilation believed
to offer advantages as a lung protective ventilator strategy. APRV is a form
of
continuous positive airway pressure (CPAP) with an intermittent release phase
from
a preset CPAP level. Similarly, APRV allows maintenance of substantially
constant
airway pressure to optimize end inspiratory pressure and lung recruitment. The

CPAP level optimizes lung recruitment to prevent or limit low volume lung
injury. In
addition, the CPAP level provides a preset pressure limit to prevent or limit
over
distension and high volume lung injury.
The intermittent release from the CPAP level augments alveolar ventilation.
Intermittent CPAP release accomplishes ventilation by lowering airway
pressure. In
contrast, conventional ventilation elevates airway pressure for tidal
ventilation.
Elevating airway pressure for ventilation increases lung volume towards total
lung
capacity (TLC), approaching or exceeding an upper inflection point of an
airway
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CA 02726604 2015-07-13
pressure ¨ volume curve (P-V curve). The P-V curve includes two limbs joined
by
upper and lower inflection points: an inspiratory or inspiration limb that is
opposite an
expiratory or expiration limb. Limiting ventilation below the upper inflection
of the P-V
curve is one the goals of lung protective strategies.
Subsequently, tidal volume reduction is necessary to limit the potential for
over distension. Tidal volume reduction produces alveolar hypoventilation and
elevated carbon dioxide levels. Reduced alveolar ventilation from tidal volume

reduction has led to a strategy to increase respiratory frequency to avoid the
adverse
effects of hypercapnia. However, increased respiratory frequency is associated
with
increase lung injury. In addition, increase in respiratory frequency decreases

inspiratory time and lessens the potential for recruitment. Furthermore,
increasing
respiratory frequency increases frequency dependency and decreases potential
to
perform ventilation on the expiratory limb of the P-V curve.
During APRV, ventilation occurs on the expiratory limb of a pressure ¨ volume
curve. The resultant expiratory tidal volume decreases lung volume,
eliminating the
need to elevate end inspiratory pressure above the upper inflection point.
Therefore,
tidal volume reduction is unnecessary. CPAP levels can be set with the goal of
optimizing recruitment without increasing the potential for over distension.
Consequently, end inspiratory pressure can be limited despite more complete
recruitment, while ventilation can be maintained.
APRV was developed to provide ventilator support to patients with respiratory
failure. Clinical use of APRV is associated with decreased airway pressures,
decreased dead space ventilation and lower intra-pulmonary shunting as
compared
to conventional volume and pressure cycled ventilation. APRV limits excessive
distension of lung units, thereby decreasing the potential for ventilator
induced lung
injury (VILI), a form of lung stress. In addition, APRV reduces minute
ventilation
requirements, allows spontaneous breathing efforts and improves cardiac
output.
APRV is a form of positive pressure ventilation that augments alveolar
ventilation and lowers peak airway pressure. Published data on APRV has
documented airway pressure reduction on the order of 30 to 40 percent over
2
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CA 02726604 2015-07-13
conventional volume and pressure cycled ventilation during experimental and
clinical
studies. Such reduction of airway pressure may reduce the risk of VILI. APRV
improves ventilation to perfusion ratio (V/Q) matching and reduces shunt
fraction
compared to conventional ventilation. Studies performed utilizing multiple
inert gas
.. dilution and excretion technique (MIGET) have demonstrated less shunt
fraction, and
dead space ventilation. Such studies suggest that APRV is associated with more

uniform distribution of inspired gas and less dead space ventilation than
conventional
positive pressure ventilation.
APRV is associated with reduction or elimination of sedative, inotropic and
neuromuscular blocking agents. APRV has also been associated with improved
hemodynamics. In a ten year review of APRV, Calzia reported no adverse
hemodynamic effects. Several studies have documented improved cardiac output,
blood pressure and oxygen delivery. Consideration of APRV as an alternative to
pharmacological or fluid therapy in the hemodynamically-compromised,
mechanically-ventilated patient has been recommended in several case reports.
APRV is a spontaneous breathing mode of ventilation that allows unrestricted
breathing effort at any time during the ventilator cycle. Spontaneous
breathing in
Acute Lung Injury/Acute Respiratory Distress Syndrome (ALI/ARDS) has been
associated with improved ventilation and perfusion, decreased dead space
ventilation and improved cardiac output and oxygen delivery. ALI/ARDS is a
pathological condition characterized by marked increase in respiratory
elastance and
resistance.
However, most patients with ALI/ARDS exhibit expiratory flow limitations.
Expiratory flow limitations results in dynamic hyperinflation and intrinsic
positive end
expiratory pressure (PEEP) development. In addition, ARDS patients experience
increased flow resistance from external ventilator valving and gas flow path
circuitry
including the endotracheal tube and the external application of PEEP.
Several mechanisms can induce expiratory flow limitations in ALI/ARDS. In
ALI/ARDS both functional reserve capacity (FRC) and expiratory flow reserve
are
reduced. Pulmonary edema development and superimposed pressure result in
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CA 02726604 2015-07-13
increased airway closing volume and trapped volume. In addition, the reduced
number of functional lung units (derecruited lung units or alveolar and
enhanced
airway closure) decrease expiratory flow reserve further. Low volume
ventilation
promotes small airway closure and gas trapping. In addition elevated levels of
PEEP
increase expiratory flow resistance. In addition to downstream resistance,
maximal
expiratory flow depends on lung volume. The elastic recoil pressure stored in
the
preceding lung inflation determines the rate of passive lung deflation.
APRV expiratory flow is enhanced by utilization of an open breathing system
and use of low (0-5 cm H20) end expiratory pressure. Ventilation on the
expiratory
limb of the P-V curve allows lower PEEP levels to prevent airway closure.
Lower
PEEP levels result when PEEP is utilized to prevent derecruitment rather than
attempting partial recruitment. Increasing PEEP levels increases expiratory
resistance, and conversely lower PEEP levels reduce expiratory resistance,
thereby
accelerating expiratory flow rates. Sustained inflation results in increased
lung
recruitment (increased functional lung units and increased recoil pressure)
and
ventilation along the expiratory limb (reduced PEEP and expiratory flow
resistance),
improving expiratory flow reserve.
In addition, release from a sustained high lung volume increases stored
energy and recoil potential, further accelerating expiratory flow rates.
Unlike low
volume ventilation, release from a high lung volume increases airway caliber
and
reduces downstream resistance. Maintenance of end expiratory lung volume
(EELV)
to eliminate the inflection point of the flow volume curve and the use of an
open
system allows reduction in circuitry flow resistance. EELV is maintained by
limiting
the release time and titrated to the inflection point of the flow time curve.
Reduced levels of end expiratory pressure are required when ventilation
occurs on the expiratory limb of the P-V curve. In ALI/ARDS, increased
capillary
permeability results in lung edema. Exudation from the intravascular space
accumulates, and superimposed pressure on dependent lung regions increases and

compresses airspaces. Dependent airspaces collapse and compressive atelectasis

results in severe V/Q mismatching and shunting. Regional transpulmonary
pressure
gradients that exist in the normal lung are exaggerated during the edematous
phase
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CA 02726604 2015-07-13
of ALI/ARDS. Patients typically being in the supine position, such that forces
directed
dorsally and cephalad progressively increase pleural pressures in dependent
lung
regions. Ventilation decreases as pleural pressure surrounding the dependent
regions lowers transalveolar pressure differentials. Full ventilatory support
during
controlled ventilation promotes formation of dependent atelectasis, increase
V/Q
mismatching and intrapulmonary shunting. Increasing airway pressure can re-
establish dependent transpulmonary pressure differential but at the risk of
over
distension of nondependent lung units.
Alternatively, spontaneous breathing, as with APRV, can increase dependent
transpulmonary pressure differentials without increasing airway pressure. APRV

allows unrestricted spontaneous breathing during any phase of the mechanical
ventilator cycle. As noted, spontaneous breathing can lower pleural pressure,
thereby increasing dependent transpulmonary pressure gradients without
additional
airway pressure. Increasing dependent transpulmonary pressure gradients
improves
recruitment and decreases V/Q mismatching and shunt.
As compared to pressure support ventilation (PSV) multiple inert gas dilution
technique, APRV provides spontaneous breathing and improved V/Q matching,
intrapulmonary shunting and dead space. In addition, APRV with spontaneous
breathing increased cardiac output. However, spontaneous breathing during
pressure support ventilation was not associated with improved V/Q matching in
the
dependent lung units. PSV required significant increases in pressure support
levels
(airway pressure) to match the same minute ventilation.
Conventional lung protective strategies are associated with increased use of
sedative agents and neuromuscular blocking agents (NMBA). The increased use of

sedative and NMBA may increase the time the patient must remain on mechanical
ventilation ("vent days") and increase complications. NMBA are associated with
prolonged paralysis and potential for nosocomial pneumonia. APRV is a form of
CPAP that allows unrestricted spontaneous breathing.
Decreased usage of sedation and neuromuscular blocking agents (NMBA)
has been reported with APRV. In some institutions, APRV has nearly eliminated
the
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use of NMBA, resulting in a significant reduction in drug costs. In addition
to drug
cost reduction, elimination of NMBA is thought to reduce the likelihood of
associated
complications such as prolonged paralysis and may facilitate weaning from
mechanical ventilation.
Mechanical ventilation remains the mainstay management for acute
respiratory failure. However, recent studies suggest that mechanical
ventilation may
produce, sustain or increase the risk of acute lung injury (ALI). Ventilator
induced
lung injury (VILI) is a form of lung stress failure associated with mechanical
ventilation and acute lung injury. Animal data suggest that lung stress
failure from
VIL1 may result from high or low volume ventilation. High volume stress
failure is a
type of stretch injury, resulting from over distension of airspaces. In
contrast, shear
force stress from repetitive airway closure during the tidal cycle from
mechanical
ventilation results in low volume lung injury.
Initially, lung protective strategy focused on low tidal volume ventilation to
limit
excessive distension and VILI. Amato in 1995 and in 1998 utilized lung
protective
strategy based on the pressure-volume (P-V) curve of the respiratory system.
Low
tidal volumes (6 ml/kg) confined ventilation between the upper and lower
inflection
points of the P-V curve. End expiratory lung volume was maintained by setting
PEEP
levels to 2 cm H20 above the lower inflection point. Amato demonstrated
improved
survival and increased ventilator free days.
However, subsequent studies by Stewart and Brower were unable to
demonstrate improved survival or ventilator free days utilizing low tidal
volume
ventilation strategy. Unlike Stewart and Brower, Amato utilized elevated end
expiratory pressure in addition to tidal volume reduction. Such important
differences
between these studies limited conclusions as to the effectiveness of low tidal

ventilation limiting ventilator associated lung injury (VALI).
Recent completion of the large controlled randomized ARDSNet trial
documented improved survival and ventilator free days utilizing low tidal
volume
ventilation (6 ml/kg) vs. traditional tidal volume ventilation (12 ml/kg).
Although the
low tidal volume group (6 ml/kg) and traditional tidal volume group (12 ml/kg)
utilized
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identical PEEP/ Fi02 scales, PEEP levels were significantly higher in the low
tidal
volume group. Higher PEEP levels were required in the low tidal volume group
in
order to meet oxygenation goals of the study. Despite improved survival in the
low
tidal volume group (6 ml/kg) over traditional tidal volume group (12 ml/kg),
survival
was higher in the Amato study. The ARDSNet trial also failed to demonstrate
any
difference in the incidence of barotrauma. The higher PEEP requirements and
the
potential for significant intrinsic PEEP from higher respiratory frequency in
the lower
tidal volume group, may have obscured potential contribution of elevated end
expiratory pressure on survival. Further studies are contemplated to address
the
issue of elevated end expiratory pressure.
In the prior art, utilization of the quasi-static inspiratory pressure versus
volume (P-V) curve has been advocated as the basis or controlling a ventilator
to
carry out mechanical ventilation. The shape of the inspiratory P-V curve is
sigmoidal
and is described as having three segments. The curve forms an upward concavity
at
low inflation pressure and a downward concavity at higher inflation pressures.

Between the lower concavity and the upper concavity is the "linear" portion of
the
curve. The pressure point resulting in rapid transition to the linear portion
of the
curve has been termed the "lower inflection point".
The lower inflection point is thought to represent recruitment of atelectatic
alveolar units. The increasing slope of the P-V curve above lower inflection
point
reflects alveolar compliance. Above the inflection point, the majority of air
spaces are
opened or "recruited". Utilizing the lower inflection point of the inspiratory
P-V curve
plus 2 cm H20 has been proposed to optimize alveolar recruitment. Optimizing
lung
recruitment prevents tidal recruitment/derecruitment and cyclic airway closure
at end
expiration. Ultimately, optimizing lung recruitment could potentially reduce
shear
force generation and low volume lung injury.
Despite an increase in the knowledge of those skilled in the relevant arts as
to
how to improve and maintain recruitment which minimizes the possibility of
VILI and
other anomalies, the systems, devices, and methods of the prior remain
difficult to
operate and employ for use with the best practice protocols. While due to many

constraints, the often-cited challenges complained of by those skilled and
practicing
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in the intensive care respiratory technical field is that a more automated and
more
accurate means is needed for applying the best practice APRV techniques.
More specifically, what has long been needed are improved devices and
modes of operation that enable a clinician to more readily configure and
reconfigure
the desired APRV approach to respond to the individual presentation of each
patient.
Preferably, such improved APRV devices and methods for use would establish the

capability to give the clinical practitioner a comprehensive starting point of
suitable
APRV parameters that could be quickly fine-tuned to meet the needs of a
particular
patient.
More preferably, such an improved method and ventilator device would also
be able to capture the real-time patient condition information used by a
clinician in
monitoring patient response to the initial APRV parameters, and to generate a
more
automated feedback loop that would enable the improved method or device to be
automatically reconfigured within clinically preferred operational and
protocol
constraints. Even more preferably, a new method and apparatus is needed that
would also enable more accurate and smaller adjustments to the various APRV
parameters that is presently possible with the present day equipment and
methods,
which must be manually adjusted. Such manual adjustments often result in
unfavorable patient response that results from inaccurate adjustments or
adjustments that cannot be made with enough precision due to the constraints
or
limited capabilities of the presently available equipment.
Most preferably, what is needed is a new and improved ventilator that
incorporates new features and a mode of operation enabling greater
flexibility, higher
accuracy, and faster clinical response times in making adjustments to the
various P-
V curve and related parameters to accommodate unexpectedly changing patient
conditions.
SUMMARY OF THE INVENTION
Many heretofore unmet needs are met and problems of the prior art are
solved with the innovative ventilator embodiments according to the principles
of the
invention. Such features and capabilities may preferably or optionally
include, among
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other elements and for purposes of illustration and example but not for
purposes of
limitation, improved and more accurate ventilation capabilities than has been
possible with the many prior attempts.
In one preferred configuration of the invention, a ventilator or ventilator
system
for assisting the respiratory function of a patient under the direction of a
clinician
contemplates the ventilator having a computerized, operation controller or
control
module or computing device that is in electronic communication with an intra-
ventilator and/or extra-ventilator electrical or data circuit or data network.
The
controller also preferably includes a display, which can be a touch-screen
display or
any other suitable display, including an application-specific, customized
display that
incorporates data input or receiving devices into the display, with or without
a touch-
screen capability.
The controller or computing device also preferably includes a memory or
storage capability that can include hard disk drives, removable drives and any

desired form of storage device. Input devices are also desirable and can
include
keyboards, mouse pointers, data entry tablets, voice-activated input devices,
and
electronic media reading devices, among many others.
Additionally contemplated input devices include wired and wireless
communications components for networking, data transfer, data capture, and
data
monitoring such as monitoring communications from electro-impedance tomography

devices, ultrasound equipment, computed and computer-aided tomography devices,
digital output fluoroscopes, x-ray equipment, magnetic resonance imaging and
spectroscopy equipment, minimally invasive surgical and bronchoscopic
visualization
devices, and similarly capable equipment.
The inventive ventilators of the invention also preferably include a gas
supply
pump and/or pressurized gas source. The gas pump or source supplies positive
pressure gas to the patient through a gas circuit or network of pipes, tubes,
hoses, or
other types of conduits. The gas network or circuit may also include at least
one and
more preferably a plurality of valves and supply and exhaust ports. More
preferably,
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a number of valves may be incorporated that can be electronically in
communication
with the controller or computing device for actuation.
Such valves can typically be included in line with the supply and exhaust
ports
and can be operable in cooperation with the various types of sensors discussed

elsewhere herein. What are often referred to as back-check valves, which
enable
fluid flow in one direction but which prevent fluid flow in an opposite
direction. Such
check valves may be included in the gas circuit or network to protect various
components and the patient from unexpected and/or undesirable pressures or
pressure shock. In this way, protection can be afforded to the patient, pump
or
pressurized gas source, sensors, and other equipment.
Other preferably optional embodiments of the invention are directed to
ventilation and control in negative pressure applications and the contemplated
gas
supply pump or pressurized gas source also may preferably incorporate, either
alone
or in combination with any of the other features described elsewhere herein, a

negative pressure or vacuum capability that is contemplated to be compatible
for use
with negative pressure thoracic or full-body cylinders, which are also
sometimes
referred to by those skilled in the ventilation and respiratory technical
fields as single,
biphasic, or multiphasic iron-lung or cuirass ventilators.
More preferably, the ventilators practiced according to the invention also
preferably include any number of optional detectors, sensors, or detection
devices,
that can be used alone or in any combination to sample and determine pressures
of
the supplied gas, inspired gas, expired gas, at rest, inflection point, and
many
different types of dynamic patient airway pressures. Other useful sensors can
include peripheral, central, and airway gas concentration sensors that can be
positioned extracorporeally in the case of well-known capnometers (for
detecting
carbon-dioxide concentrations) or infrared oximeters (for detecting oxygen
concentrations).
These types of devices can be attached to extremities such as fingers, toes,
or ear lobes, which make it very convenient to sample, monitor, and detect
peripheral
concentrations or saturations of carbon dioxide (SpCO2) and oxygen (Sp02). For
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other contemplated ventilation applications, central line catheters or other
techniques
can enable monitoring of arterial 02 and CO2 gas concentrations (Pa02,PaCO2),
which can have clinical value in certain ventilation modes of operation or
protocols
discussed elsewhere herein. For purposes of the instant invention, such
pressure
and gas concentration sensors are more preferably configured to electronically

communicate with the contemplated controller or computing device of the
ventilator
so that the real-time and/or near-real-time data can be monitored as described
in
more detail below.
The inventive ventilator also contemplates incorporation of any number of
equally suitable fluid flow rate sensors that also may be adapted to
communicate
with the data network, the data circuits, and/or directly with the controller
or control
module or computing device, and either wirelessly or over wired connections.
Such
flow rate monitoring devices can be employed in multiple places in the gas
network
or circuit to monitor the total amount of gas supplied, inspired, expired, as
well as the
speed at which such activity is occurring or has occurred. With this
information,
pressure can be compared to total volume or rate of volumetric or mass flow of
gas
so that the novel ventilators can better control and ensure proper ventilation
of the
target respiratory system of the patient.
Additionally, such controls can improve the accuracy with which pressurized
gas is supplied to the patient, and can lessen the risk of lung injury by
monitoring
and keeping gas flow rates within acceptable protocol limits. In any number of

possible preferred configurations, the sensors can be arranged as a sensor
array to
simultaneously monitor any one or any number of ventilation-related parameters
so
as to maximize control over the ventilation procedure to ensure the best
possible
protocol implementation under the circumstances. In many preferably optional
configurations of the invention, any of the noted sensors may be positioned
proximate to and/or about the gas supply and/or exhaust ports, among other
places
in the gas network or circuit.
A command module, command routine, algorithm, commander, firmware, or
program may preferably be resident in the memory or storage components of the
controller or computing device. The command module is preferably operative to
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control the sensors, to control the supply pump, to receive communications or
images or information from other devices, to receive input from the clinician
or
another via any of the contemplated input devices, and to operate the display
to
present prompts and/or display important information pertaining to the
ventilation
process. The command module may also be optionally configured to preferably
communicate various ventilator information to other devices, to other wireless
or
wired networks, to the display for contemporaneous viewing, and to other
remote
devices and locations as may be desired.
Preferably, the control module may adjustably and/or variably actuate the
pump or pressure source to vary the volume and/or pressure supplied thereby.
Further, the control module or command routine may more preferably be modified
to
also automatically, manually, or otherwise operate any of the plurality of
valves,
either alone or in combination with the control of the pump, for even more
rigorous
control over the pressure, volume, flow rate, and gas supply cycle times
available for
use in ventilating the patient. More preferably, the control module or command

routine may preferably be adapted to coordinate such control of the valves
with
sampling of or receipt of information from any of the contemplated sensors to
establish increased accuracy in sampling one or more pressure readings, gas
concentrations, and/or volume or mass flow rates anywhere in the gas circuit
or
network, or the patient undergoing ventilation.
The present invention also contemplates operational compatibility with any
number of conventionally accepted, investigational, and experimental
ventilation
modes. More preferably, the operational capability of the invention enables
many
heretofore unavailable hybrid modes wherein the innovative ventilator
automatically
changes its mode of operation in response to patient progress or difficulties.
For
example, the ventilator can be configured to commence ventilation in a
mandatory
breath mode, and to monitor various patient pressure, volumetric, and gas
concentration responses, among other responses, that may indicate a patient
who
was formerly heavily sedated and unable to breathe, has suddenly started to
attempt
to breathe spontaneously.
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Upon such detection, the inventive ventilation will automatically switch among

many modes of operation including from full-support mandatory breath modes, to

various modes having lesser degrees of breathing support, so as to cooperate
with
the patient's attempts to breathe independently. Additionally, if the patient
relapses
and discontinues spontaneous breathing attempts, the ventilator will revert to
full,
mandatory breath mode. To enable such capabilities, the new ventilator of the
invention is preferably preconfigured with various automated and
reconfigurable
modes of operation. For purposes of assisting clinicians with selecting fully
automated modes of operation, or to enable partial or fully customizable modes
of
operation, the optionally preferred configurations of the invention enable the
clinician
to select any particularly desired automated mode of operation.
Additionally, the clinician may also select an automated mode of operation
and then modify only the desired parameters. Even further, the clinician may
ignore
the fully automated modes, and may enter preferred settings to select a fully
customized mode of operation suitable for purposes of any conceivable
ventilation
protocol or mode of operation. In one particularly useful configuration, the
ventilator
incorporates the controller or control module or computing device to have
three
primary operational modules, including, for purposes of example but not for
purposes
of limitation, an initial setup module, an adjustment and maintenance module,
and a
weaning module.
In turn, the initial setup module includes among other elements, an optimal
end expiratory lung volume (OEELV) sub-module that monitors a number of key
patient parameters to ascertain and periodically compute the OEELV. The
adjustment and maintenance module includes oxygenation, recruitment, and
ventilation sub-modules of operation and protocols that are tightly
constrained to
rigorously and aggressively monitor and protect the key aspects of these
ventilation
operational modes. This is accomplished using precisely bounded monitoring
paradigms that enable very gradual and extremely accurate changes to manage
CO2
ventilation, to ensure optimal oxygen saturation, and, when needed, to
exercise and
maximize alveolar recruitment and prevent derecruitment. If any parameters
experience unexpected or uncontrolled hysteresis, alarm events are triggered
to
enable intervention.
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The weaning module includes an initial weaning assessment sub-module that
enables close monitoring and small, slow changes to assess patient response to

reduced ventilator support with rapid fall back to full support as needed.
With positive
patient response, the initial weaning assessment sub-module enables complete
ventilator reconfiguration into subsequently less supportive ventilation
protocols for
further weaning. Also included in the weaning module is an airway pressure
release
ventilation or APRV sub-module wherein spontaneous patient breaths are closely

monitored so that support can be weaned as the patient gains control and
consistency. With continued improvement, control is passed to the CPAP sub-
module, which cycles up to a maximum CPAP support mode that is then gradually
reduced to a minimal support mode until an extubation pressure is reached, at
which
point the patient is completely weaned from the ventilator.
For purposes of achieving these various modes of use, any of preferred or
optional variations of the inventive ventilator may be predefined with or may
receive
and capture a number of parameters that can control how the ventilator
operates in
its various modes of operation. The controller or computing device may access
stored parameters, may obtain new parameters from remote devices via wired or
wireless communications, and may accept user input via the noted touch-screen
display or any of the other input devices. Whatever the source of the
operational
settings or parameter, the information is typically stored in a database or an
array
that is stored in the memory or storage of the controller or computing device.
In one
optionally preferred embodiment, these parameters are accessibly stored in one
or
more initialization parameter database(s), which may be resident in the
controller
memory or storage.
These initialization parameters can be accessed and displayed or
communicated to any other device. Alone or in combination with this database,
additional subsets of parameters may be grouped together in arrays such as one
or
more model patient data arrays or elements, which can be predefined to
represent
optimum ventilator settings that are well suited for a particular type of
presenting
patient or disease.
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For purposes of illustration, but not for purposes of limitation, such data
arrays
or initialization parameter databases may include, among other parameters and
information, a PEEP, a target peripheral 02 concentration or an Sp02 quantity,
an
end tidal CO2 or etCO2 quantity, a fraction of inspired 02 or Fi02 quantity, a
high
pressure or P(high) that defines the maximum inspired pressure during
mandatory or
positive pressure assisted breaths, a low pressure or P(low) that can define a

minimum pressure to be used during expiration and which can be zero or non-
zero.
Other parameters can include a high time or T(high) that represents a period
of
inspiration during P(high) and a low time or T(low) that can represent a small
period
of time during which expiratory gas is expelled.
It may also be optionally preferred to include predefined or predetermined
pressure change increments or pressure increments, P(inc), and time
increments,
T(inc), which can be any amount, and for which there can be multiple different
preset
increments that can be used as needed and so that clinical intervention may
not be
needed in more automated modes of operation. It has also been found to be
sometimes desirable to store one or more tidal volumes, respiratory
frequencies for
mandatory breaths, to establish and store one or more pressure-volume curve
slopes, and to establish one or more trigger pressures that enable the
ventilator to
detect a pressure drop trigger, which may indicate the patient is trying to
spontaneously breathe.
In yet further optionally preferred variations, the ventilator may also be
configured so that the command module can receive such initialization settings
from
the user or the clinician via the input device. Such settings can include
those
described elsewhere herein or any other possibly desirable parameters that can

improve the use of the ventilator. Once any preferred settings and/or
parameters are
entered into the controller and/or command routine, the supply pump is
actuated to
begin ventilation within the constraints of the selected automated program or
settings
or the manually entered parameters and settings.
During operation, the command module or routine samples, polls, or
otherwise communicates with, any or all of the sensors in the array and
measures
the patient's actual data. A series of such sensor readings may be sampled so
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an entire array of such data elements can be used to monitor patient response
and
ventilator performance, and to adapt the ventilator performance in response to

patient status and condition. For purposes of example without limitation,
sensor data
that can be gathered may optionally include a patient Sp02 partial pressure
(PP) or
quantity, a patient etCO2 PP or quantity, a peak expiratory flow rate (PEER),
an end
expiratory lung volume (EELV) and a spontaneous frequency or machine
respiratory
frequency.
Once measured or sampled, the actual patient data array elements can be
compared by the command module to any of the stored data to ascertain
ventilator
performance and patient response. For further example, such actual data may be

compared to the one model patient data array. In this way, it can be
determined
whether the patient is responding favorably to ventilation. In another
example, if the
patient is responding well to ventilation, then a comparison between the
patient's
Sp02 and etCO2 and a comparable model patient data set would be acceptable. If

acceptable, then the control routine can compute or generate a flag or Boolean
value
such as an Sp02 goal value and an etCO2 goal value that can be set to true,
meaning the actual patient measurements indicate all is well. If not, then a
false flag
can be generated to enable the control routine to modify its behavior or seek
clinical
intervention by generating an alarm condition. Additionally, the control
routine can
poll pressure sensors and flow sensors during certain points in the
inspiration and
expiration phases of ventilation to ascertain an OEELV, which can provide
clinically
relevant feedback identifying patient response and ventilator performance.
In yet other optionally preferred configurations, the ventilator may be
configured to modify its behavior in response to unfavorable patient response.
For
further example, assume the SpO2was unfavorable and the SpO2goal value is
false,
which indicates undesirable oxygenation. As discussed in more detail elsewhere

herein, the command module can preferably determine that increased or modified
adjustments in ventilation are warranted to achieve the desired Sp02 level. To
that
end, the command module will adjust the operation of the pump, and functioning
of
the valves, and perhaps the concentration of supplied oxygen in the
pressurized gas
supply, and may thereby increase the P(high) the pressure increment, it may
increase the T(high) by the time increment. In the alternative, it may be
instead
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preferable to only modify the various operational parameters of the ventilator
to
increase or decrease the F102 quantity.
More preferably, in circumstances where the patient is responding well and it
is warranted to start gently weaning from the ventilator support, the command
module can instead set a flag or Boolean constant, such as an initial weaning
value
to be true, which can serve to notify other modules of the ventilator that
weaning may
begin. Conversely, if the patient is experiencing difficulties that may
include non-
perfused pulmonary dead space, it may be advantageous to modify the ventilator
behavior to encourage recruitment of alveolar tissues. In certain
circumstances, it
may be advisable to generate an alarm signal seeking intervention. In other
less
challenging circumstances, it may desirable to set a recruitment flag or
Boolean
value to notify other control routine modules that a recruitment process is
advisable.
In this circumstance, the control routine can modify the pump and valve
operation to
establish operation suitable for recruitment, which can include increasing
P(high) by
one or more P(inc), increasing T(high) by one or more T(inc)s, and/or
adjusting
T(low) by one or more T(inc)s.
In other situations where recruitment may not be indicated, it may be
desirable
to increase lung oxygenation. If so, the controller or computing device may
make
adjustments to the ventilator operation whereby an oxygenation flag or Boolean

value is set to be true, which can invoke an oxygenation module that can poll
the
sensors to measure the peak expiratory flow rate and then compute an angle of
deceleration of gas flow so that an appropriate time adjustment may be made,
or so
that T(low) may be decreased by one or more T(inc).
In yet other equally useful modes of operation, the ventilator can invoke an
alveolar ventilation approach wherein the command module compares the
spontaneous frequency to the machine respiratory frequency, ascertains the
P(high),
T(high), computes a minute ventilation (MV) value, adjusts the supply pump and

valves to increase T(high) and P(high) by respective T(inc) and P(inc).
Similarly, a
minute ventilation and recruitment module may be invoked wherein the MV is
computed as a function of the currently in use P(high) and T(high), and
adjustments
are made to the P(high) and T(high).
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In more favorable patient response scenarios, an initial weaning assessment
sub-module may be utilized wherein the command module or command routine
samples the machine respiratory frequency and spontaneous respiratory
frequency
to ascertain that spontaneous breathing is occurring at a certain rate.
Comparing this
rate to a predefined rate gives a good indication of whether an initial
weaning
assessment sub-module can be employed. If so, then the command routine can
test
for apnea and tachypnea. If neither condition is indicated, then the
ventilator can be
switched to a more suitable mode, such as an APRV mode, which makes it much
easier for the intubated patient to breathe spontaneously.
As the patient who is experiencing initial ventilator weaning continues to
improve, another mode of the ventilator enables a weaning module wherein
spontaneous breathing and blood gas levels continue to be monitored while the
P(high) is decreased while the T(high) is increased. In this way, the patient
is
encouraged to continue spontaneous breaths.
As improvements mount, further weaning is warranted. In this instance, the
ventilator operates in another mode wherein weaning criteria can be considered
in
comparison to the actual patient data that is being monitored. In one suitable
set of
predetermined weaning criteria, an Fi02 threshold, an Sp02 threshold, a
spontaneous tidal volume, a minute ventilation quantity, and an airway
occlusion
pressure (P0.1) are compared to the patient's actual values. If the patient
fails to
meet these criteria, then weaning is discontinued temporarily and more
breathing
support is given to the patient. In weaning failure, the control routine
increases the
P(high) and decreases T(high). Conversely, if the weaning criteria are passed
by the
patient's actual values, then the command module repeatedly initiates the
cyclic
weaning protocol wherein P(high) is decreased and T(high) is increased. The
airway
occlusion pressure P0.1 is measured and trended over time by a P0.1 module and
is
used to assess the work of breathing during spontaneous breaths. In the
preferred
embodiments, this is used to assess the impact of weaning and the resultant
work of
breathing, as is explained in connection with other modules elsewhere herein.
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Assuming for further purposes of illustration that the patient continues
improving, then the command module changes ventilator operation again, and
monitors P(high) until a CPAP threshold is reached, which enables another
conversion of the ventilator operation into a CPAP sub-module. This sub-module
is
much more comfortable for patients, and reduces the dependence of the
ventilator.
As the further improvements are manifested, the command module begins to
gradually reduce the CPAP pressure until an extubation threshold pressure is
reached. Also, it may be optionally preferable during the CPAP and other modes
of
operation to enable the controller to incorporate an automatic tube
compensation
pressure or ATC pressure which boosts the ventilator support just enough to
overcome the frictional losses encountered when breathing through the gas
network
or circuit of tubing involved in use of the ventilator.
In operation, various methods of use of the ventilator are possible using any
of
the embodiments of the invention and modifications, variations, and
alternative
arrangements thereof. Using any of the physical configurations of the
inventive
ventilators described elsewhere herein, one method of use involves entering
settings
via the input device including at least one of (i) an automated initialization
setting and
(ii) a parameter to be stored in the memory that includes at least one of (a)
a PEEP
quantity, (b) an Sp02 quantity, (c) an etCO2 quantity, (d) an Fi02 quantity,
(e) a high
pressure, (f) a low pressure, (g) a high time, (h) a low time, (i) a pressure
increment,
(j) a time increment, (k) a tidal volume, (I) a respiratory frequency, (m) a
pressure-
volume slope, (n) a trigger pressure, and (o) a predetermined weaning criteria

including at least one of an F102 threshold, an Sp02 threshold, a spontaneous
tidal
volume, a minute ventilation quantity, and an airway occlusion pressure
(P0.1).
Next, the command routine receives the settings from the clinician via the
input device and commands the controller to actuate the supply pump. This
commences respiratory assistance to the patient whereby the gas circuit
communicates with the patient using one each of the Fi02 quantity, the high
and low
pressure, and the high and low time. Patient actual data array elements are
measured by using the command routine to communicate with the plurality of
sensors. Measurement of at least one of (i) a patient Sp02 quantity, (ii) a
patient
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etCO2 quantity, (iii) a peak expiratory flow rate, (iv) an end expiratory lung
volume
and (v) a spontaneous frequency, is taken.
The command routine compares the patient actual data array to at least one
of the settings and computes at least one of an Sp02 goal value, an etCO2 goal

value, and an optimal end expiratory lung volume, which values are used to
determine whether the patient should be initially weaned, undergo recruitment
and
increased oxygenation, or be maintained in an unaltered state of ventilation.
If the patient is improving, then measuring and comparing at least one of the
patient actual data array elements to the predetermined weaning criteria to
set a flag
or Boolean weaning value to true is warranted (meaning the patient did not
fail the
weaning test). If passed, the cyclic weaning is initiated by adjusting at
least one of
the supply pump and the plurality of valves to decrease the P(high) by one or
more
pressure increments.
Also, to decrease the ventilator support even further, the T(high) is
gradually
increased and the P(high) is gradually decreased until the CPAP threshold is
reached, where after the ventilator is switched into CPAP mode where it
remains
until the CPAP pressure may be decreased until the extubation threshold
pressure is
reached, after which the patient may be removed from the ventilator.
In other optionally preferred novel embodiments, any of the monitoring
devices, sensors, computers, or computing devices may be connected with any of
the other components wirelessly or with a wire. Any of the contemplated
components
may also be in communication with any of the other components across a
network,
through a phone line, a power line, conductor, or cable, and/or over the
internet. In
other alternatively preferred configurations of the invention, the resident
software
program may have numerous features that, for purposes of example without
limitation, enable different functionalities.
More preferably, such resident software program and/or programs may enable
any of the contemplated information to be communicated by text, voice, fax,
and/or
email messages either periodically, when certain predefined or predetermined
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conditions occur, such as predefined alarm events or conditions, and/or when
anomalous, unexpected, or expected power readings occur and/or are detected.
These variations, modifications, and alterations of the various preferred and
optional embodiments may be used either alone or in combination with one
another
and with the features and elements already known in the prior art and also
herein
contemplated and described, which can be better understood by those with
relevant
skills in the art by reference to the following detailed description of the
preferred
embodiments and the accompanying figures and drawings.
BRIEF DESCRIPTION OF THE DRAWING(S)
Without limiting the scope of the present invention as claimed below, and
referring now to the drawings and figures, wherein like reference numerals
across
the drawings, figures, and views refer to identical, corresponding, or
equivalent
elements, methods, components, features, and systems:
FIG. 1 shows a ventilator and system in accordance with the present
invention;
FIG. 2 shows a schematic diagram of the operation of the ventilator and
system of FIG. 1;
FIGs. 3a and 3b are schematic diagrams of an OEELV sub-module of
operation of the ventilator and system of FIG. 1;
FIG. 4 shows a schematic diagram of the interrelationships between the
modules of operation of the ventilator and system of FIG. 1;
FIG. 5 shows a schematic diagram of an oxygenation sub-module of operation
of the ventilator and system of FIG. 1;
FIG. 6 is a schematic diagram of a recruitment sub-module of operation of the
ventilator and system of FIG. 1;
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FIG. 7 is a schematic diagram of a ventilation sub-module of operation of the
ventilator and system of FIG. 1;
FIG. 8 is schematic diagram of an initial weaning assessment sub-module of
operation of the ventilator and system of FIG. 1;
FIG. 9 is schematic diagram of an ARPV sub-module of operation of the
ventilator and system of FIG. 1;
FIG. 10 is a schematic diagram of a CPAP sub-module of operation of the
ventilator and system of FIG. 1;
FIG. 11 is an area diagram of an OEELV sub-module and assessment of
operation of the ventilator and system of FIG. 1;
FIG. 12 is an area diagram of an OEILV sub-module and assessment of
operation of the ventilator and system of FIG. 1;
FIG. 13 is an area diagram of a spontaneous breathing sub-module and
assessment of operation of the ventilator and system of FIG. 1;
FIG. 14 is a schematic airway pressure versus time tracing for airway
pressure release ventilation;
FIG. 15 is an airway pressure versus time tracing during the inspiratory
P(high) phase of ventilation;
FIG. 16 is an airway volume versus pressure curve illustrating a shift from
the
inspiratory limb to the expiratory limb thereof;
FIG. 17 is an inspiratory and expiratory gas flow versus time tracing for
airway
pressure release ventilation;
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FIG. 18 is an expiratory gas flow versus time tracing;
FIG. 19 is a set of expiratory gas flow versus time tracing illustrating
determination of whether flow pattern is normal, restrictive or obstructive
based on
the shape of the tracing; and
FIG. 20 is a set of airway pressure versus time tracings illustrating
ventilation
weaning by successive reductions in pressure P(high) and substantially
contemporaneous increases in time T(high).
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the various figures and illustrations, those skilled in the
relevant arts should appreciate that each of the preferred, optional,
modified, and
alternative embodiments of the inventive ventilator and ventilator system 10
and
method of operation contemplate interchangeability with all of the various
features,
components, modifications, and variations within the scope of knowledge of
those
skilled in the relevant fields of technology and illustrated throughout the
written
description, claims, and pictorial illustrations herein.
With this guiding concept in mind, and with reference now to FIG. 1, one
possible embodiment of a ventilator and ventilator system 10 is illustrated,
which is in
communication with the patient P undergoing ventilation therapy. The
ventilator and
ventilator system 10 also preferably includes a gas supply pump and/or
pressurized
gas source 12 having a positive pressure port 14, and optionally a negative
pressure
port 16. The gas pump or source 12 supplies positive pressure gas 14 and can
also
supply negative pressure or a vacuum 16 for non-invasive negative pressure
applications such as iron-lung or similar therapies. A wide variety of
commercially
available ventilators may be modified according to the principles of the
invention and
one such device includes what is referred as the model EvitaXL, which is
available
from Draeger Medical, Inc. of Telford, Pennsylvania, USA, and Lubeck, Germany.
The ventilator 10 also preferably includes a controller or control module or
computing device 20 that is in electronic communication with an intra-
ventilator
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and/or extra-ventilator electrical or data circuit or data network 22. The
controller 20
also preferably includes a display 26. The display 26 may be a conventional
device
that receives unidirectional signals from the controller 20, but may also be
any of a
number of possibly preferred bidirectional devices such as a touch-screen
display
that can be used as an input device 28, and which may also have a data entry
capability such as a built-in keyboard or keypad similar to the keyboard input
device
28 shown in FIG. 1.
The controller or computing device 20 also preferably includes a memory or
storage capability 24 that can include flash drives, optical media, hard disk
drives,
solid state disk drives, random access memory, non-volatile memory, removable
storage devices, remote internet-based storage devices, network appliance-type

devices, and the like.
Typically, the gas supply pump or pressurized gas source 12 communicates
positive or negative pressure to the patient P through a gas circuit or
network of
tubes 40. The gas network or circuit 40 may also include an inspiration or
supply port
42 and an expiratory or exhaust port 44. A number of valves are usually also
included to control and meter fluid flow and would preferably include a supply
valve
46, a sensor valve (not shown), and an exhaust valve 52, all of which would
likely be
in communication with the controller 20 via the data network 22 so that the
command
module 30 may control and operate the valves automatically to start and stop
ventilation and to control pressure and flows rates to the patient P during
operation.
The supply and exhaust valves 46 and 52 may be also operable to
periodically close for short periods of time to enable pressure sensors to
obtain
various static pressure readings. Additionally, the sensor valve may be
operable to
close such as to protect various sensors from pressure circuit transients and
to
prevent spurious readings such as when the ventilator 10 may be automatically
responding to patient P improvements or relapses by changing modes of
operation
from mandatory breathing support to augmentative support modes.
In addition to the contemplated input devices described elsewhere herein,
there may be certain diagnostic imaging devices that can be incorporated into
the
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operation of the ventilator 10 of the invention to communicate quantitative
pulmonary
function information such lung volume, dead space ratios, and the like.
Additional
and possible useful devices may also include, for purposes of example without
limitation, electro-impedance tomography devices 70, ultrasound equipment 80,
computed and computer-aided tomography devices 90, and other types of Doppler
imaging sensors 95 that may enable various quantitative or subjective
pulmonary
function imagery.
Various types of optionally preferred detectors, sensors, or detection
devices,
also have utility for purposes of the invention to enable precise control and
analysis
of volumetric and mass flow rates as well as pressures of the supplied gas,
inspired
gas, and expired gas, which in turn enables calculation of various other
static and
dynamic pulmonary function parameters, as is discussed in more detail
elsewhere
herein.
With continued reference to FIG. 1, a group of sensors 54 can be arrayed
proximate to the ventilator 10 and patient P. An oximeter or 02 saturation
sensor 56
may be used peripherally to ascertain peripheral or venous 02 content Sp02 and
a
capnography sensor or capnometer or CO2 sensor 58 may be used to determine end
tidal or peripheral CO2 saturation levels (etCO2, SpCO2). For certain
applications
involving long term supine ventilation, it may be desired to also monitor
arterial blood
gas concentrations, among other parameters. In these instances, invasive
methods
can be used such as central line catheters to assess pulmonary arterial 02 and
CO2
levels using a Pa02sensor 60 and/or a PaCO2sensor 62.
It is also optionally preferred to monitor various airway pressures,
volumetric,
and mass flow rates so that patient P response can be continuously assessed.
For
purposes of monitoring airway pressures, an airway pressure sensor or pressure

gauge 64 can be placed in a number of places along the gas network or circuit,
and
is more preferably positioned proximate to the supply and exhaust ports 42, 44
at the
intubation site of the patient P. An airway flow sensor 66 can be similarly
positioned
to enable monitoring of volumetric flow rates of inspiratory and expiratory
gases. In
certain applications, it has been found desirable to employ strain gauges
mounted on
the thorax to enable monitoring of chest movement during pulmonary breathing
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cycles, which can be an additional source of volumetric pulmonary patient P
function
as well as a source of patient P work expended for spontaneous breaths.
With reference now also to FIG. 2, the ventilator 10 also incorporates the
control module 20 and/or the command module 30 to include three primary
operational modules, including, for purposes of example but not for purposes
of
limitation, an initial setup module or protocol 100, an adjustment and
maintenance
module 200, and a weaning module 250. During initial ventilator 10 startup, a
number of initial parameters are set based upon input from the clinician or by
accessing a predefined set of parameters. With reference now also to FIGS. 2,
3,
and 4, the preliminary initialization routines will be described. In FIG. 4,
it can be
seen that the clinician may enter their preferred settings 110 into the
display 26 or
input device 28. In the alternative, any number of possible predefined
automated
settings 120 may be accessed and used as defined or customized in whole or in
part
to prepare the ventilator 10 for operation. Once the clinician or automated
settings
110, 120 are selected, the settings 110, 120 are populated with various other
initialization parameters 130 during the operation of the initial setup module
100. As
the operation of the ventilator 10 commences, the command module 30 invokes an

OEELV sub-module or assessment routine 150.
With specific reference now to FIGS. 3a and 3b, it can be seen that the
initial
setup module 100 includes the OEELV sub-module or assessment routine 150. The
OEELV sub-module 150 periodically and on demand will determine a ventilation
range as a function of obstructiveness of the lung and the hypocarbic, normal,
and/or
hypercarbic condition of the patient P. As part of the evaluation, the OEELV
sub-
module 150 determines whether the computationally ascertained OEELV is in the
range appropriate for the conditional status of the patient P. For example
without
limitation, if the patient P has obstructive lungs, and is experiencing high
range
hypoventilation, i.e., hypercarbia, then an appropriate or desired OEELV
should be in
the range of about 30% to 40%.
If the computationally ascertained OEELV is higher than this range, then the
T(low) parameter is increased by 0.05 seconds. Conversely, if the
computationally
ascertained OEELV is lower than the desirable range of 30% to 40%, then the
T(low)
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parameter is lowered with the intent to achieve the appropriate OEELV range.
In this
way, the novel OEELV sub-module 150 can execute very fine adjustments of
actual
OEELV to stimulate optimum conditioning of the ventilated patient's P
pulmonary
response. To wit, adjustments of 0.05 seconds in T(low) will enable slow and
gradual
optimization of the OEELV best suited to the disease modality. Although for
purposes
of illustration and explication of various aspects of the invention,
increments of 0.05
seconds or other amounts of time have been described. However, the principles
of
the invention in this aspect are also suitable for even more gradual changes
in time,
and can include milliseconds and smaller and larger orders of magnitude.
Once T(low) is set, the OEELV sub-module 150 relinquishes control for a
period of time and the command module 30 again resumes control to then invoke
the
adjustment and maintenance module 200, which includes an oxygenation sub-
module 300, a recruitment sub-module 400, and a ventilation sub-module 500.
The
module 200 and its component sub-modules 300, 400, and 500 include protocols
configured to rigorously monitor and protect the key aspects of the patient's
P
physiological ventilation and pulmonary response profile to enable maximized
recovery and weaning with minimum pulmonary injury risk. During the ensuing
ventilation process, the patient's P Sp02 and etCO2 are continuously monitored
via
the respective Sp02 and etCO2 sensors 56, 58 to ensure a target or goal of
Sp02 of
at least about 95% and etCO2 of no more than between about 34 to 45 mm Hg are
maintained (FIG. 4).
The command module 30 next passes control to oxygenation sub-module
300, which is described in more detail specifically in FIGS. 4 and 5. As the
oxygenation sub-module 300 assumes control for a short period of time, the
Sp02 is
again assessed so that adjustments may be made as required in the fractionally

inspired 02, which is otherwise referred to as the Fi02 parameter 360. Once
adjustments are made to Fi02 320, 340, 350, the command module 30 cooperates
with the oxygenation sub-module 300 to assess whether a P(high) pressure
adjustment must be made or whether the initial weaning assessment sub-module
600 is invoked. If the patient P is responding well, and if the Fi02 330 and
Sp02 310
quantities are suitable, then control will be transferred to the initial
weaning
assessment sub-module 600, which is discussed in more detail elsewhere herein.
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In the alternative, the oxygenation sub-module 300 and command module 30
assess the P(high) condition 380. If P(high) is adjusted 390, then another
iteration of
the OEELV sub-module 150 is also conducted to support the optimum OEELV sub-
module 150 discussed earlier. As control returns to the oxygenation sub-module
300,
P(high) is again assessed 370 to determine whether recruitment sub-module 400
is
warranted or whether P(high) must again be adjusted. Assuming for purposes of
further illustration that recruitment sub-module 400 is indicated, the
oxygenation sub-
module 300 relinquishes control to command module 30, which invokes the
recruitment sub-module 400.
Referring now also to FIG. 6, recruitment sub-module 400 reevaluates the
P(high) condition in a different context 420, 430, 450, as depicted in more
detail in
FIG. 6. In the circumstance where P(high) becomes greater than 40 cm H20 450,
an
alarm signal 410 is sounded to affect immediate intervention. Otherwise,
P(high) is
adjusted 460, 390, 480 to improve the pulmonary condition of patient P and the
Sp02
is again iteratively re-examined 310 while recruitment sub-module 400
continues
attempts to increase lung surface, reduce dead space, and re-inflate alveolar
units
as much as possible until Sp02 values 310 indicate the need for oxygenation
sub-
module 300. Feedback of information from other concurrently running modes may
be
sampled periodically via feedback loop 180 by command module 30, which can
interrupt recruitment as needed and transfer control or invoke a more
important
mode when required by patient P physiology. For example, if command module 30
detects inbound information from feedback loop 180 describing increased etCO2
values approaching or exceeding desired limits, control can revoked by command

module 30 so that ventilation sub-module 500 can be invoked.
With continued reference to the previously discussed figures and now also to
FIG. 7, command module 30 invokes ventilation sub-module 500 to redress an
actual or approaching out of limit etCO2 condition. The ventilation sub-module
500
re-evaluates end tidal CO2 levels 510, reassesses OEELV conditions, and then
assesses patient P breath spontaneity 570 against the set rate or respiratory
frequency values obtained from the clinician 110 or automated settings 120. If

breathing spontaneity remains at or below the set rate 570, then an alveolar
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ventilation sub-module 504 is affected to adjust T(high) 530, 540 and P(high)
370,
390 as may be needed to further optimize pulmonary response.
However, as patient P recovers pulmonary responsiveness and breath
spontaneity improves beyond the set rate of, for purposes example without
limitation,
to a rate of 15 spontaneous breaths over the set rate, then an alveolar
ventilation
sub-module 504 is effected whereby T(high) 530, P(high) 370 are adjusted
separately, and then in combination 520 for lower values of P(high). For
higher
values of P(high), the minute ventilation sub-module 506 evaluates Vt 560 to
determine whether recruitment sub-module 400 is warranted. If not, then Sp02
is
again verified 310, T(high) is adjusted 550, and the patient P is examined
against a
tachypnea assessment worksheet 590 that is a function of the set rate or
respiratory
frequency and the actual patient P rate defined in the assessment worksheet
590. As
with other modules, the command module 30 continues to poll for information
inbound on the feedback loop 180 so that control can be instantly seized to
maintain
optimal pulmonary response parameters across the spectrum of continuously
monitored variables.
Attention is now invited also to FIG. 8 with the hypothetical suggestion that
command module 30 recalled control from the ventilation sub-module 500 for
another pass through the oxygenation sub-module 300, and the parameters were
evaluated favorably for the command module 30 to invoke the initial weaning
assessment sub-module 600. As with other modules, the Fi02 330, Sp02 310,
etCO2
510, breathing spontaneity 570, and possible tachypnea (spontaneous breathing
15
above the set rate) 580 are re-evaluated. Assuming patient P responds well,
then
P(high) is assessed 610 and if warranted, the spontaneity of breathing is
compared
against apnea parameters 620. The markedly improving patient P will then
experience one of the very novel aspects of the inventive ventilator 10 as the

command module 30 reconfigures the ventilator 10 away from the mandatory
breath
control mode and invokes an assisted breathing mode. If the patient P does not

respond well, P(high) and T(high) are adjusted 630 and the command module 30
again invokes the initial weaning assessment sub-module 600 to reassess Fi02
330,
Sp02 310, etCO2 510 and breathing spontaneity 570, 580.
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With reference now also to FIG. 9, those knowledgeable in the pertinent fields

of expertise will appreciate that the command module 30 invokes an airway
positive
release ventilation or APRV sub-module 700, which can be much more comfortable

for the recovering pulmonary patient P. Here too, the APRV sub-module 700 re-
verifies the pulmonary conditioning of the patient P and examines P(high) 610.

However, unlike other modules, the APRV sub-module 700 institutes a new
parameter evaluation set referred to herein as the weaning criteria 710. These

criteria evaluate the patient P against a more rigorous series of critical
pulmonary
physiological conditions to ensure the patient can withstand the added
stresses of
substantially less gradual changes in the ventilation sub-module of operation.
Before
the command module 30 discontinues the mandatory breathing modes of operation,

the patient P must pass these weaning criteria 710. If the patient P fails the
weaning
criteria 710, then the command module 30 re-invokes the initial weaning
assessment
sub-module 600, or another module if feedback loop 180 alerts the command
module 30 to a more urgent requirement.
Assuming the weaning criteria 710 are met, however, then the patient P is
deemed able to withstand greater changes in the pressure-volume slope profile
being induced by the ventilator and ventilator system 10. Accordingly, the
APRV sub-
module 700 effects additional adjustments 720 to wean or reduce the patient's
P
reliance on the mandatory breathing modality of the ventilator 10. This
weaning
process and re-evaluation 720, 730, 710 continues to iterate if well tolerated
by the
patient P until P(high) is less than or equal to a pressure of only 20 cm H20.
At this
point, the patient P is recovering well and absent an important indication to
the
contrary over the feedback loop 180, the command module 30 again completely
reconfigures the operational profiles of the ventilator 10.
As illustrated in detail in FIG. 10, the commander or command module 30
invokes the CPAP sub-module 800 in a maximum CPAP assistance mode, which
speeds up the process of removing the patient P from reliance on the
ventilator 10.
P(high) is assessed 810 and the patient P continues to be evaluated against
the
weaning criteria 710, and for gross and undesirable deviations from acceptable

pulmonary response limits, in which case CPAP is increased 830. As the
patient's P
recovery accelerates, the CPAP sub-module 800 decreases assistance 820, 840,
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850, until an extubation pressure 860 is reached. Hereafter, the clinician
intervenes
and extubates the weaned patient P.
Among many possible modifications to any of the embodiments of the
inventive ventilator 10, one particularly useful variant includes a modified
OEELV
sub-module (not shown), that can be incorporated as an improvement to the
OEELV
sub-module 150, or which may be included as an independent mode capable of
operating and cooperating with OEELV sub-module 150. With continued reference
to
the various figures and especially to FIGS. 3a and 3b, and with reference now
also
now to FIG. 11, those having an understanding of the relevant areas of
technology
may recall that OEELV is derived by using the elements and reference points
information acquired during the P(low)IT(low) cycle as is described elsewhere
herein. The proposed and optionally preferred OEELV sub-module 150 is ideally
functioning for the duration of the ventilation therapy and is operative to
continuously
optimize EELV, or end expiratory lung volume, of the therapeutic patient P.
The derived OEELV is a function of disease state (see, e.g., FIGS. 3a and
3b), and the patient's P pulmonary responsiveness to the oxygenation sub-
module
300, recruitment sub-module 400, and ventilation sub-module 500. In a
compliant
patient P, the OEELV sub-module 150 optimizes EELV by adjusting the T(low)
time
period. Preferably, the OEELV sub-module 150 also validates the acquired
information by using multiple sampling, averaging, and various statistical
methods
over time for validation and error detection.
Adjustments of the OEELV are based upon the elements and flow and time
reference points acquired during the P(low)/T(low) cycle. Flow and time
reference
points within the flow/time area, which is established by the P(low)/f(low)
cycle, may
be used to measure and calculate changes occurring in lung volume during the
P(low)/T(low) cycle. For purposes of example and further illustration, but not
for
purposes of limitation, and looking again to FIG. 11, the preferred OEELV sub-
module 150 measures the peak expiratory flow rate (PEER) 1100, the decay phase

1110, and the truncation phase 1120 to calculate the angle of deceleration
(ADEC) of
gas flow and the termination of the flow of gas to determine optimal T(low)
adjustment. The OEELV sub-module 150 thereby enables a heretofore unavailable
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dynamic adjustment, which more accurately and more responsively establishes
and
maintains the most optimal actual OEELV of the patient P.
An analysis of FIG. 11 ought to reveal to those skilled in the arts that an
extrapolation phase 1130 may be used to calculate a residual volume and
pressure
as a function of time. The PEFR 1100 of FIG. 11 represents the rapid
depressurization evidenced by the relaxation and recoil of the thorax after
the
machine breath. The decay phase 1110 represents the decaying energy drive and
the downstream resistance to gas flow. The flow termination phase or
truncation
phase 1120 establishes the point in the time course of flow where the flow can
be
determined either as a function of the disease process, or the parameter
setting that
was input by the user or clinician. The extrapolation phase 1130 can be used
graphically and/or algebraically to determine and calculate pressure, volume,
and
time.
As described elsewhere herein, and with continued attention to FIG. 11, we
recall that the OEELV sub-module 150 as well as the OEELV sub-module 150 both
measure the peak expiratory flow and the truncation of gas flow, and then uses
this
information to calculate the ADEC or angle of deceleration, which is in turn
used to
establish the ideal OEELV value. With this approach, it should be observed
that
changes in the truncation point will change the angle of deceleration. When
the
resulting angle becomes less acute, the resultant observation is that
recruitment has
occurred. Conversely, when the angle becomes more acute, derecruitment is
indicated.
Therefore, the OEELV sub-module 150 suggest adjustments to at least one of
P(high), P(low), T(high), or T(low). In the instance where derecruitment is
detected,
P(high) or T(high) should be increased, or T(low) should be decreased, or some

combination thereof should be effected. On the other hand, if recruitment is
detected
in this way, P(high) should be decreased, T(high) or T(low) should be
increased, or
some combination thereof should be effected.
The present invention also contemplates in any of the embodiments of the
invention an optimal end inspiratory lung volume (OEILV) sub-module 1200 than
can
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further augment aspects of the recruitment sub-module 400 of FIG. 6. In this
alternative variation to any of the embodiments of the innovative ventilator
and
ventilator system 10, the OEILV sub-module 1200 is optionally or preferably
invoked
by the command module 30 as needed. More preferably, the OEILV sub-module
1200 is invoked by the recruitment sub-module 400. Even more preferably, the
OEILV sub-module 1200 is invoked by the recruitment sub-module 400 at any
moment outside the actual recruitment phases or inspiratory pressurization
because
the OEILV sub-module 1200 ideally assesses for derecruitment and is active or
engaged only during the machine or ventilator 10 breath. Most preferably, the
OEILV
sub-module 1200 monitors the existing sensor data to identify changes in flow
and
time during the P(high)/T(high) cycle of ventilation.
When invoked, the OEILV sub-module 1200 is active over time during the
machine breath and acquires recorded reference points of the flow/time course
to
P(high)/T(high) cycle. The OEILV sub-module 1200 uses this acquired data to
identify changes in flow and time coordinate grid during the P(high)/T(high)
cycle. If
such changes are in fact identified, the OEILV sub-module 1200 may preferably
communicate a message to the command module 30, the recruitment sub-module
400, and/or over the feedback loop 180, to initiate recruitment. Even more
preferably,
the OEILV sub-module 1200 may also suggest and/or effect manual or automated
adjustments to P(high) and/or T(high) to further minimize actual or
prospective
derecruitment and/or to improve the pulmonary conditions of the ventilation
therapy
and/or the response or conditioning of the patient P.
In the non-recruitment phase of the recruitment sub-module 400, the OEILV
sub-module 1200, when active, preferably may also intermittently adjust
P(high),
T(high), or both, and/or may notify the command module 30, the feedback loop
180,
and/or other modules of the recommended adjustments, and/or may communicate to

the clinician manually or automatically so as to seek clinical intervention if
warranted.
These adjustments in P(high), T(high), or both, may be applied in an
occasional,
intermittent, and/or cyclic manner, and may be effected either manually,
through
informative messages, or through automation.
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CA 02726604 2015-07-13
In further aspects of the optionally preferred OEILV sub-module 1200, and
with reference also to FIG. 12, the OEILV sub-module 1200 may preferably
incorporate a resistive element 1210 that occurs during the onset of the
machine
breath, an inflection point 1250 that correlates with an inflection or a half-
way point of
the machine breath cycle (the resistive-elastic transition point), and an
elastic
element 1220 that corresponds with the relaxing subsequent to the machine
breath.
It is important to note that the OEILV sub-module 1200 measures the inflection
point
1250 to determine if the slope of the elastic element 1220 changes.
In other words, the inquiry seeks to learn whether the elastic element 1220
becomes more acute in derecruitment and less acute in recruitment. Those
skilled in
the arts may come to understand that the combination of information available
from
FIGS. 11 and 12 and the accompanying discussion herein enables a heretofore
unavailable means of more accurately discerning whether recruitment has been
accomplished or whether derecruitment has occurred. The various modes now
available and according to the principles of the invention enable more
accurate and
more automated systems for better managing and mitigating recruitment and
derecruitment during many possible ventilation therapy protocols.
In any of the embodiments of the inventive ventilator 10 and modes and
methods of operation, the breathing spontaneity can be further assessed using
an
optionally preferred spontaneous breathing sub-module 1340 that is graphically

depicted in FIG. 13. This spontaneous breathing sub-module 1340 may be further

invoked by any of the other modes, modules, and routines of the inventive
ventilator
10. Even so, this spontaneous breathing sub-module 1340 may find special
utility in
being optionally invoked through the command module 30 alone and/or by either
the
ventilation sub-module 500 or by the initial weaning assessment sub-module
600.
In addition to comparing the actual spontaneous breaths per unit time of the
patient P, this sub-module 1340 may preferably assess and analyze the nature
of
spontaneous breathing to identify and quantify breathing effort, otherwise
referred to
as the "work of breathing." More preferably, the spontaneous breathing sub-
module
1340 assesses the effect of weaning on the work of breathing. Any of the
sensors
described elsewhere herein, such as one or more of the strain gauges 68, can
be
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CA 02726604 2015-07-13
elastically or tightly affixed to the thorax of the patient P to sense and
record
movement, and solid-state or similarly capable accelerometers can also be used
to
gain additional data points that can be used to compute actual work expended
to
breathe.
Referring to FIG. 13 again, such data points can be correlated against a
spontaneous breath initiation phase 1360, a spontaneous peak phase 1370, and a

spontaneous termination phase 1380. Even more preferably, such data can be
adduced during any of the spontaneous breath evaluations 570, 580 (FIGS. 7 and
8)
occurring during the ventilation and initial weaning assessment sub-modules
500,
600, as well as any other suitable time. These additional indicia of the
pulmonary
conditioning and response of the patient P can further illuminate the
patient's P true
cardiopulmonary physiology, which can lessen the risk that the patient P is
prematurely removed from ventilation therapy due to patient P resistance or
other
issues.
With continued reference to the various figures and preceding discussion,
those knowledgeable in the relevant arts may appreciate that for certain
preferred
circumstances, the invention also contemplates initiating ventilation of the
patient P
in an APRV sub-module 700 based on initial oxygenation and ventilation
settings.
The patient P can then have the safety of the mandatory breath capability of
the
ventilator 10 while commencing ventilation therapy with a less intrusive
profile. The
ARPV airway pressure during expiration (P(low)) is substantially zero
throughout
ventilation to allow for the rapid acceleration of expiratory gas flow rates.
Typically,
the fraction of oxygen in the inspired gas (F102) is initially set at about
0.5 to 1.0 (i.e.,
about 50% to 100%). The highest airway pressure achieved during inspiration
(P(high)) must be sufficiently high to overcome airspace-closing forces and
initiate
recruitment of lung volume. P(high) may suitably be initialized at a default
value of
about 35 cm H20.
Alternatively, P(high) may be established based on either the severity and
type of lung injury or the recruitment pressure requirements. The latter
method is
preferred in cases where the ratio of the partial pressure of oxygen in the
blood of
the patient P to the fraction of oxygen present in the inspired gas (i.e.,
Pa02/Fi02,
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CA 02726604 2015-07-13
which is commonly abbreviated as P/F) is less than or equal to about two
hundred
millimeters of mercury (200 mm Hg). The P/F ratio is preferably monitored
continuously.
Where the type and severity of lung injury are characterized by a P/F of
greater than about 350 mm Hg, an initial value of P(high) within the range of
about
20 cm H20 to 28 cm H20 is preferably established. On the other hand, if the
P/F ratio
is less than about 350 mm Hg, P(high) is preferably initialized within the
range of
about 28 cm H20 to 35 cm H20.
In situations where the P/F ratio is less than or equal to about 200 mm Hg,
which may occur where the patient's P initial injury is non-pulmonary and/or
the lung
injury is of an indirect nature, the invention contemplates establishment of
P(high) at
a value of between about 35 mm Hg and 40 mm Hg but preferably not appreciably
above 40 mm Hg. In cases where P(high) is initially established at a default
value of
about 35 cm H20, P(high) is reduced from such a value once P/F exceeds about
250
mm Hg. Initiation of ventilation also requires the establishment of time
(duration)
settings for inspiration and expiration.
Initially, the duration of the positive pressure phase (T(high)) is
established at
a value within the range of about 5.0 to about 6.0 seconds unless the measured

PaCO2 is greater than about 60 mm Hg. In that case, T(high) is more preferably
set
to a lower initial value of within the range of about 4.0 to 5.0 seconds. The
duration
of the ventilator 10 release phase (T(low)) may suitably be initialized at a
value within
the range of 0.5 to 0.8 seconds with about 0.7 seconds being a preferred
default
value.
Once initial values of P(high), P(low), T(high) and T(low) have been
established, ventilation continues in a repetitive APRV mode cycle generally
as
illustrated in FIG. 14. During management of ventilation in accordance with
the
invention, the initial values of one or more of these parameters are re-
assessed and
modified in accordance with measured parameters as has been described in
connection with earlier descriptions.
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CA 02726604 2015-07-13
In management of ventilation in accordance with the invention, a principal
goal
is to maintain the level of carbon dioxide in the blood of the ventilated
patient P
(PaCO2) at a level of less than or equal to about 50 mm Hg. Toward that end,
arterial
PaCO2 is monitored continuously or measured as clinically indicated and the
ventilator 10 controlled to adjust ventilation as follows. Any time after
ventilation has
commenced, but preferably soon thereafter or promptly upon any indication of
hypercarbia (PaCO2 above about 50 mm Hg), the setting of T((ow) is optionally
but
preferably checked and re-adjusted if necessary.
According to the invention, optimal end expiratory lung volume is maintained
by titration of the duration of the expiration or release phase by terminating
T(low)
based on expiratory gas flow. To do so, the flow rate of the expiratory gas is

measured by the ventilator 10 and checked in relation to the time at which the

controller of the ventilator 10 initiates termination of the release phase.
The
expiratory exhaust valve should be actuated to terminate the release phase
T(low),
at a time when the flow rate of the expiratory gas has decreased to about 25%
to
50% of its absolute peak expiratory flow rate (PEFR) based on gas flow tracing
and
pulmonary disease process. An example is illustrated in FIG. 17. In that
example,
T(low) terminates by controlling the expiratory exhaust valve to terminate the
release
phase when the expiratory gas flow rate diminishes to 40% PEFR.
If monitoring of PaCO2 indicates hypocarbia is present (i.e., PaCO2 less than
about 50 mm Hg), T(high) is increased by about 0.5 seconds while maintaining
P(high) substantially unchanged. Should the patient P remain hypocarbic as
indicated by subsequent measure of PaCO2, weaning in the manner to be
described
may be initiated provided oxygenation is satisfactory and weaning is not
otherwise
contraindicated based on criteria to be described further below.
The hypercarbic patient P though is not to be weaned. In the event of
hypercarbia, the invention contemplates assessment of the expiratory flow
pattern
before making significant further adjustments to ventilation parameters. This
assessment can readily be carried out by a software program stored within the
control unit of the ventilator 10, which carries out automated analysis of the

expiration flow versus time tracing. As illustrated in FIG. 19, normal
expiratory flow is
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CA 02726604 2015-07-13
characterized by flow that declines substantially monotonically from the onset
of the
release phase through its termination and does not fall off prematurely or
abruptly.
Restrictive flow in contrast declines rapidly from the onset of the release
phase to
zero or a relatively small value. Obstructive flow tends to be more extended
in
duration and is characterized by an inflection point beyond which the rate of
flow falls
off markedly from its initial rate.
FIG. 18 illustrates a gas flow pattern with a noticeable inflection point
based
on analysis of flow data provided by expiratory flow sensors, the control unit
of the
ventilator 10 is programmed to determine reference points during the
P(low)IT(low)
cycle. Flow and time reference points within the flow/time area, which is
created or
established by the P(low)IT(low) cycle, may be used to measure and calculate
changes occurring in lung volume during the P(low)IT(low) cycle. If it is
determined
that obstructive or restrictive flow is present, the invention contemplates
adjusting
T(low) before making any other significant adjustments to ventilation
parameters.
This can be done according to either of two alternative methods.
One method is to adjust T(low) to a predetermined value according to whether
flow is either obstructive or restrictive but allowing T(low) to remain at its
previous
value if flow is normal. In the case of restrictive flow, T(low) should be
adjusted to
less than about 0.7 seconds. On the other hand, obstructive flow calls for a
T(low) of
greater duration, preferably greater than about 0.7 seconds with 1.0 to 1.2
being
typical.
It is optional but advisable to promptly assess the sedation level of the
hypercarbic patient P. Sedation of the patient P can be evaluated by any
suitable
technique such as the conventional clinical technique of determining a
sedation
agitation scale (SAS) score for the patient P. If the patient P appears over-
sedated
based on the SAS score (SAS score greater than about 2) or otherwise,
reduction of
sedation should be considered and initiated if appropriate. Thereafter,
T(high) should
be increased by about 0.5 seconds and P(high) increased concomitantly by about
2
cm H20. After allowing sufficient time for these adjustments to take effect on
the
patient P, PaCO2 should be re-evaluated. If the patient P remains hypercarbic,

T(high) should be increased again by about 0.5 seconds and P(high) again
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CA 02726604 2015-07-13
increased concomitantly by about 2 cm H20. PaCO2 should then be reassessed and

concomitant increases of about 0.5 seconds in T(high) and about 2 cm H20 in
P(high) repeated until the patient P is no longer hypercarbic. However, the
total
duration of T(high) should not be increased beyond a maximum of about fifteen
(15)
seconds.
Management of oxygenation in accordance with the invention is carried out
with the goal of maintaining the level of oxygen in the arterial blood of the
ventilated
patient P (Pa02) at a value of at least about 80 mm Hg and a maintaining
saturation
level (Sa02) of at least about 95%. Preferably, fluctuations of Pa02 are held
within a
target range of about 55 mm Hg and 80 mm Hg. (Expressed in terms of Sp02, the
target range would be between about 0.88 and 0.95, although where Pa02 and
Sp02
data are both available, Pa02 would take precedence.) Responsive to a
determination that oxygenation and saturation both meet the goals just
specified, the
ventilator 10 would be controlled to progressively decrease the fraction of
oxygen in
the inspired gas (Fi02) by about 0.5 about every thirty (30) minutes to one
(1) hour
with the objective of maintaining a blood oxygen saturation level (Sa02) of
about
95% at a P(high) of about 35 cm H20 and an Fi02 of about 0.5. Upon meeting the

latter objective, weaning in the manner to be described may be initiated
provided the
ventilation goal described earlier (i.e. a PaCO2 of less than about 50 mm Hg)
is met
and weaning is not otherwise contraindicated.
However, if the goals of oxygenation of Pa02 of at least about 80 mm Hg and
arterial blood oxygen saturation (Sa02) of at least about 95% cannot both be
maintained at the then-current Fi02, Fi02 is not decreased. Instead, P(high)
is
increased to about 40 cm H20 and T(high) increased substantially
contemporaneously by about 0.5 seconds.
If such action does not result in raising oxygenation and saturation to at
least
the goals of Pa02 of about 80 mm Hg and Sa02 of about 95%, P(high) is
increased
to a maximum of about 45 cm H20 and T(high) is progressively further increased
by
about 0.5 seconds to 1.0 seconds. Oxygenation and saturation are then re-
evaluated
and, if they remain below goal, Fi02, if initially less than 1.0, may
optionally be
increased to about 1Ø Oxygen and saturation continue to be re-evaluated, and
39
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CA 02726604 2015-07-13
T(high) successively raised in increments of about 0.5 to 1.0 seconds until
the stated
oxygen and saturation goals are met.
Once those oxygenation and saturation goals are met, ventilation is controlled
to maintain those goals while progressively decreasing Fi02 and P(high) toward
the
levels at which initiation of weaning can be considered. More particularly,
P(high) is
decreased by about 1 cm H20 per hour while Fi02 is decreased by about 0.05
about
every thirty (30) minutes while maintaining an oxygen saturation of at least
about
95%.
Weaning according to the invention, unless otherwise contraindicated, may
commence after the oxygenation and ventilation goals described above have been

met. That is, when PaCO2 remains below about 50 mm Hg and Sa02 remains at
least about 95% at a P(high) of about 35 cm H20 and Fi02, if previously
higher, has
been weaned to a level of not greater than about 0.5. During weaning in
accordance
with the invention, T(high) is controlled to sustain recruitment while P(high)
is
reduced to gradually reduce airway pressure. As FIG. 20 illustrates, this is
achieved
by carrying out a series of successive incremental reductions in P(high) while

substantially contemporaneously carrying out a series of successive
incremental
increases in T(high) so as to induce gradual pulmonary stress relaxation as
FIG. 15
illustrates.
As a result, the pulmonary pressure versus volume curve shifts progressively
from its inspiratory limb to its expiratory limb as illustrated in FIG. 16. As
can be
understood with reference to the previously described figures, weaning may be
carried out in two stages, the first of which is more gradual than the second.
During
the first stage, P(high) is reduced by about 2 cm H20 about every hour.
Substantially
contemporaneously with each reduction in P(high), T(high) is increased by
about 0.5
to 1.0 seconds up to, but not in excess of a T(high) of about 15 seconds in
total
duration.
As P(high) is being reduced in the manner just described, the fraction of
oxygen in the inspired gas (Fi02) is also gradually reduced in accordance with

P(high). During the first stage of weaning, this gradual weaning of Fi02 is
carried out
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CA 02726604 2015-07-13
gradually. When P(high) has been reduced to about 24 cm H20 and Fi02 weaned to

about 0.4 with the patient P sustaining a blood oxygen saturation (Sa02) of at
least
about 95% weaning may proceed to the more aggressive second stage. The term
"substantially contemporaneously" should not be construed to be limited to
necessarily require that changes occur precisely at the same moment. Rather,
the
term is to be construed broadly to encompass not merely events that occur at
the
same time, but also any which are close enough in time to achieve the
advantages
or effects described.
During continued weaning, successive reductions in P(high) and substantially
contemporaneous increases in T(high) contemporaneous reductions continue about

once every hour. However, during the second stage, the reductions in P(high)
take
place in increments of about 4 cm H20 and the increases in T(high) are each
about
2.0 seconds. As reductions in P(high) continue, further weaning of F102 is
implemented. Once Fi02 is weaned to about 0.3, airway pressures are reduced
such
that the ventilation sub-module by then has been transitioned from APRV to a
substantially Continuous Positive Airway Pressure/Automatic Tube Compensation
Mode (CPAP/ATC).
Once the patient P is tolerating CPAP at about 5 cm H20 with Fi02 of not
greater than about 0.5, the patient's P ability to maintain unassisted
breathing is
assessed, preferably for at least about two (2) hours or more. Criteria for
such
assessments include: a) Sp02 of at least about 0.90 and/or Pa02 of at least
about 60
mm Hg; b) tidal volume of not less than about 4 ml/kg of ideal bodyweight; c)
respiration rate not significantly above about 35 breaths per minute, and d)
lack of
respiratory distress, with such distress being indicated by the presence of
any two or
more of the following: i) Heart rate greater than 120% of the morning-hour
rate
(though less than about five (5) minutes above such rate may be considered
acceptable) ii) marked use of accessory muscles to assist breathing; iii)
thoroco-
abdominal paradox; iv) diaphoresis and/or v) marked subjective dyspnea.
If there is an indication of respiratory distress, CPAP at an airway pressure
of
about 10 cm H20 should be resumed and monitoring and reassessment carried out
as needed. However, if criteria a) through d) above are all satisfied, the
patient P
41
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CA 02726604 2015-07-13
may be transitioned to substantially unassisted breathing such as by
extubation with
face mask, nasal prong oxygen or room air, T-tube breathing, tracheotomy mask
breathing or use of high flow CPAP at about 5 cm H20.
During all phases of ventilation, including initiation, management and
weaning, the patient P should be reassessed at least about every two (2) hours
and
more frequently if indicated. Blood gas measurements (Pa02, Sa02 and PaCO2)
which govern control of ventilation according to the invention should be
monitored
not less frequently than every two (2) hours though substantially continuous
.. monitoring of all parameters would be ideal.
Just prior to and during weaning at least one special assessment should be
conducted daily, preferably in the morning hours. If not possible to do so, a
delay of
not more than about four (4) hours could be tolerated. Weaning should not be
initiated or continued further unless: (a) at least about 12 hours have passed
since
initial ventilation settings were established or first changed, (b) the
patient P is not
receiving neuromuscular blocking agents and is without neuromuscular blockade,

and (c) Systolic arterial pressure is at least about 90 mm Hg without
vasopressors
(other than "renal" dose dopamine).
If these criteria are all met, a trial should be conducted by ventilating the
patient P in CPAP mode at about 5 cm H20 and an Fi02 of about 0.5 for about
five
(5) minutes. If the respiration rate of the patient P does not exceed about 35
breaths
per minute (bpm) during the five (5) minute period weaning as described above
may
proceed. However, if during the five (5) minute period the respiration rate
exceeds
about 35 bpm, it should be determined whether such tachypnea is associated
with
anxiety. If so, administer appropriate treatment for the anxiety and repeat
the trial
within about four (4) hours. If tachypnea does not appear to be associated
with
anxiety, resume management of ventilation at the parameter settings in effect
prior to
the trial and resume management of ventilation as described above. Re-assess
at
least daily until weaning as described above can be initiated.
42
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CA 02726604 2015-07-13
INDUSTRIAL APPLICABILITY
The embodiments of the present invention are suitable for use in many
respiratory assistance applications that involve the use of ventilators and
ventilator
systems and methods of operation thereof. The various configurations and
capabilities of the inventive ventilator and system and method of operation
can be
modified to accommodate nearly any conceivable respiratory assistance
application
and/or requirement. The arrangement, capability, and compatibility of the
features
and components of the novel ventilators, systems, and methods of operation and

use described herein can be readily modified according to the principles of
the
invention as may be required to suit any particular critical and/or routine
care and/or
hospital, assisted care, or home care application or situation. Additionally,
such
inventive ventilators, systems, and methods are suitable for use with nearly
all types
of ventilation equipment including but not limited to positive pressure or
negative
pressure respiratory assistance devices.
Such modifications and alternative arrangements may be further preferred
and/or optionally desired to establish compatibility with the wide variety of
possible
applications that are susceptible for use with the inventive and improved
ventilators,
respiratory assistance systems, and operational methods that are described and
contemplated herein.
The scope of the claims should not be limited by the preferred embodiments
set forth in the examples, but should be given the broadest interpretation
consistent
with the Description as a whole.
43
4203540 v2

Representative Drawing
A single figure which represents the drawing illustrating the invention.
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Administrative Status

Title Date
Forecasted Issue Date 2023-09-12
(86) PCT Filing Date 2008-06-02
(87) PCT Publication Date 2008-12-04
(85) National Entry 2010-12-01
Examination Requested 2013-05-17
Correction of Dead Application 2019-08-13
(45) Issued 2023-09-12

Abandonment History

Abandonment Date Reason Reinstatement Date
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2021-07-05 R86(2) - Failure to Respond 2022-06-30

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Payment History

Fee Type Anniversary Year Due Date Amount Paid Paid Date
Reinstatement of rights $200.00 2010-12-01
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Reinstatement - failure to respond to examiners report $200.00 2017-07-13
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Reinstatement - failure to respond to examiners report $200.00 2019-08-07
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Reinstatement - failure to respond to examiners report 2022-06-30 $203.59 2022-06-30
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Final Fee $306.00 2023-07-07
Owners on Record

Note: Records showing the ownership history in alphabetical order.

Current Owners on Record
HABASHI, NADER M.
Past Owners on Record
INTENSIVE CARE ON-LINE NETWORK, INC.
Past Owners that do not appear in the "Owners on Record" listing will appear in other documentation within the application.
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