Note: Descriptions are shown in the official language in which they were submitted.
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Multifunction valve
The invention relates to a multifunction valve comprising at least three
connectors.
A stopcock comprising a housing defining at least three connectors is known
in the prior art from WO 2006/025054 A2.
Mounting pressure transducers on a retaining plate which is located at a
distance of approximately 150 cm away from a patient is known in the prior
art. This requires that an at least equally long pressure line be provided.
However, the measurement results become inaccurate due to effects of this
long pressure line. Touching the pressure line can also distort the
measurement results.
It is not possible to connect a pressure transducer in such a way using
standard components that a pressure signal can be recorded with high
accuracy and precision close to the catheter tube, without detriment to basic
functions of such a measuring system, such as flushing and blood withdrawal.
This gives rises to the object of providing a device with which a pressure
signal can be recorded with high accuracy and precision, and which
simultaneously provides basic functions, such as flushing, blood withdrawal
and zeroing of the pressure transducer.
This object is achieved by a multifunction valve comprising at least three
connectors, wherein a first connector can be connected to a catheter, a
second connector to an infusion and a third connector to a pressure
transducer, wherein in a first position the first and second connectors are
connected to each other via a first channel, in a second position the first
and
third connectors are connected via a second channel, and the second and
third connectors are connected to each other via a third channel, in a third
position the second and third connectors are connected to each other via the
second channel, and the first connector is closed, and the third channel has a
smaller cross-section than the second channel. It is advantageous that the
pressure transducer be protected when a wire is pushed between the second
and first connectors. The wire is guided in the first channel, which in the
first
position has no connection to the pressure transducer, thus preventing any
contact between the wire and the pressure transducer. The introduction of gel
by the wire into the catheter from a gel transfer membrane of a pressure
sensor is also prevented in this manner.
The multifunction valve preferably used is a multipath stopcock which controls
flow between three connectors. It is particularly preferred to use a stopcock
which can block one or several paths connected to it.
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The connectors are preferably biocompatible. The connectors are preferably
liquid-tight as well, so that they can be connected to hypodermic needles,
syringes, infusion tubes, catheters and/or pressure transducers. The
connectors are preferably provided with a thread and a cap nut in order to
secure and lock the connector against inadvertent release. The connectors
are preferably cylindrical, particularly preferably cone-shaped. The
connectors
on the muitifunction valve are preferably intemal cones or internal cylinders.
In
another preferred embodiment, the connectors on the multifunction valve are
external cones or external cylinders. The connector is preferably connected
by pushing together it and the components to be connected. The connectors
of the multifunction valve are preferably blunt and configured for adhesive
connection. Likewise preferred is a connection produced by squeezing or
clamping. This connection is opened and closed particularly preferably by one
tum, and most highly preferably by one half-turn. The connectors are
particularly preferably configured as Luer lock connectors.
The catheter used can be any catheter that has an open lumen. It is
preferable to use heart catheters or vein catheters and it is especially
preferred to use arterial catheters. The catheters used are capillaries or
tubes
with which hollow organs can be probed, evacuated, filled and/or flushed, or
with which the pressure is said hollow organs can be measured.
The infusion fluids are preferably administered intravenously or intra-
arterially.
The fluids preferably used are flushing solutions, blood, blood substitutes,
plasma substitutes, electrolyte solutions, non-ionic solutions and/or
pharmaceuticals. Glucose soiution, saline solution and Ringer's lactate
solution are particularly preferably used.
The pressure transducer preferably measures the absolute pressure, and
particularly preferably the pressure differential. The size of the pressure
transducer is preferably between 1/10 mm and 10 cm.
The first channel is preferably a recess in the multifunction valve,
particularly
preferably a through hole. The second channel is preferably a through hole,
particularly preferably a recess in the multifunction valve. The third channel
is
preferably a recess in the multifunction valve, particularly preferably a
through
hole.
In the second position, the pressure of the gas and/or fluid fed through the
second channel can be measured via the third connector, while the
multifunction valve is simultaneously flushed via the third channel. Since the
third channel has a smaller cross-section than the second channel, flushing
has a minimal influence on the pressure.
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The cross-sectional area of the channels correspond to the area of the
surface exposed with a cut at an angle of 900 to the longitudinal axis of the
channel.
The first and second connectors lie preferably opposite one another. As a
result, gases and/or fluids can proceed from the first into the second
connector, or vice versa, without changes in the direction of flow. Energy
losses due to friction and/or turbulence on the part of the gases and/or
fluids
flowing through the connectors are minimized as a result.
The first and second connectors are preferably open towards opposite sides
of a plane which extends between the first and second connectors. A
particularly preferred embodiment is one in which the angle between the first
and second connectors is greater than 90 . It is particularly preferred that
the
angle between the first and second connectors is 180 .
The multifunction valve preferably has a housing. The housing protects the
interior of the multifunction valve and seals off the interior of the
multifunction
valve against the ambient surroundings. The housing is preferably liquid-
tight,
so that fluids are unable to escape from the interior to the ambient
surroundings.
Markings for one or several switch positions are preferably provided on the
housing of the multifunction valve. In addition, the housing preferably has
catches for one or several switch positions. It is particularly preferred that
the
housing has stops for one or several switch positions.
The pressure transducer is preferably connected to the housing, and it is
particularly preferred that the pressure transducer is mounted directly in or
on
the housing. By this means, the pressure can be measured directly in or on
the multifunction valve. In this way, measurements with high temporal
resolution can be achieved. This measurement is therefore especially suitable
for analyzing the natural shape of a pressure curve. Negative effects of
additional tube lines are also eliminated in this way.
The third channel is particularly preferably a capillary. As a consequence,
the
effect of flushing on the result of pressure measurement is especially slight.
The capillary is preferably a very fine, elongated cavity. A particularly
preferred
embodiment is one in which the capillary is a glass capillary or a lasered
hole.
The length of the capillary is preferably between 1/10 mm and 12 mm, and the
diameter is preferably between 1/100 mm and 4/10 mm. Flow volumes of
between 2 and 20 mi per hour can thus be achieved when the flushing
solution is impinged with standard pressures of approximately 300 mm Hg.
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The first channel, the second channel and the third channel are preferably
arranged in a switching mechanism that can be tumed inside the housing.
The connectors are thus connected in a simple manner via the channels and
according to the different positions. The third channel is provided
particularly
preferably in the housing, or partly in the housing and partly in the
switching
mechanism. If the third channel is provided partly or completely in the
housing, it is preferably embodied as a capillary.
The switching mechanism is preferably adapted to influence the direction or
strength of throughflow. This is particularly preferably achieved by means of
a
mechanical component that can influence the flow by its position or change of
position. It is particularly preferred that the switching mechanism can be
tumed inside the housing. The switching mechanism can preferably be tumed
about one of its own axes. It is particularly preferred that the switching
mechanism is in two parts, since this allows it to be produced in a
particularly
simple manner.
The first channel preferably has slight kinks with an angle of less than 6 .
The
first channel is embodied particularly preferably as a through hole. As a
result,
the first and the second connectors can be connected in a simple manner in
the first position. This also makes it easier to use a guide wire. In the case
of
kinks with angles greater than 6 , the guide wire might suffer damage or
cause abrasion in the lumen. This also prevents changes in the direction of a
gas or liquid flowing through the first channel.
The through hole preferably has openings at the two opposite ends of its
longitudinal axis. A particularly preferred embodiment is one in which the
openings are both as large as the cross-section of the through hole. It is
particularly preferred that the cross-section of the through hole is equal in
size
in all regions of the through hole.
The first channel preferably runs transversely through the switching
mechanism. In this way, the first and second connectors can be connected to
each other in a particularly simple manner.
The first channel preferably runs non-parallel to the turning axis of the
switching mechanism. In a particularly preferred embodiment, the first channel
extends in a direction that is perpendicular to the turning axis of the
switching
mechanism. It is particularly preferred that the first channel intersects the
tuming axis of the switching mechanism.
A direction vector of the first channel, a direction vector of the third
channel
and a vector which points from a reference point of the first channel to a
reference point of the third channel are preferably linearly independent. A
direction vector of the first channel is a vector which points in the first
position
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of the multifunction valve in the direction of flow of a fluid from the first
connector to the second connector. A direction vector of the first channel is
a
vector which points in the second position of the multifunction valve in the
direction of flow of a fluid from the third connector to the second connector.
Linearly independent preferably means that none of the vectors can be
depicted as a linear combination of the other vectors.
The first channel and the third channel are preferably not connected to each
other. This prevents the first channel from being filled via the third channel
in
the second and third positions.
There is preferably no way for fluids to pass through between the first and
the
third channel, and it is particularly preferred that there is no way for gases
to
pass through.
The second channel is preferably embodied as a groove in the switching
mechanism. This means that the second channel can be produced in a
particularly simple manner.
The groove is preferably a recess in the switching mechanism. A particularly
preferred embodiment is one in which the groove is an elongated recess.
The second channel preferably runs substantially in the circumferential
direction of the switching mechanism. This makes it possible for connectors
that are arranged in the circumferential direction to be connected to each
other in a simple manner.
The second channel preferably extends along more than 50% of its length in
the circumferential direction of the switching mechanism. It is particularly
preferred that it extends along more than 70% of its length in the initial
direction of the switching mechanism.
The second and third channels are preferably connected to each other. This
makes it possible to connect three connectors to each other.
The second and third channels are preferably connected by a passage for
gases, and particularly preferably by a passage for fluids.
The second channel preferably has a dilation in an end portion and is
connected in the region of the dilation to the third channel. This makes it
particularly simple to guide the third channel past the first channel.
The dilation of the second channel preferably extends in the end portion in
the
longitudinal direction of the switching mechanism. The third channel
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preferably ends in the region of the channel that extends in the longitudinal
direction of the switching mechanism.
The second channel is preferably embodied as a through hole. In this way,
the wetted sealing faces between the housing and the switching mechanism
are small when measuring the pressure. The formation of deposits can be
prevented particularly well in this way.
The cross-section of the second channel is preferably identical over the
entire
length of the channel. It is particularly preferred that the channel has a
round
cross-section. As a result, the flow characteristics of a fluid flowing
through
the channel are modrFed to a particularly small extent.
A catheter system preferably has a multifunction valve that can be connected
to a catheter tube. In this way, a catheter system is provided that can be
connected via the catheter tube to the body of a patient and which can be
connected via the multifunction valve to medical apparatus.
A catheter system is a system that preferably has a plurality of components,
wherein one of the components is a catheter tube.
A catheter tube is a tube made of metal, glass or preferably plastic, and
particularly preferably of silicone, polyethylene or polyurethane, with which
hollow organs can be probed, evacuated, fiiled or flushed, or with which the
pressure therein can be measured. The tube is preferably deformable.
The catheter system preferably has a multifunction valve to which a pressure
transducer can be connected. By this means, the pressure in the catheter
tube can be measured. The measured pressure values are particularly
accurate and precise because measurements are carried out very close to the
section of the patient's circulation that is of interest.
The catheter system preferably has a pressure transducer to which a plug
connector can be connected. By this means, it is possible for apparatus to be
connected to the pressure transducer. These apparatus are preferably alarm
devices that generate an optical, preferably acoustical alarm when the
pressure exceeds and/or falls below a critical pressure. These apparatus are
particularty preferably recording devices for recording the pressure. The
pressure is preferably recorded as a printout, particulariy preferably in
electronic, analog, digital or numerical form and particularly preferably in
the
form of a graph.
A plug connector is a connector with which electricity, preferably optical
signals, particularly preferably electrical signals are transferred from one
module to another module.
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A device preferably has a catheter system that can be connected to a blood
withdrawal port. In this way, blood can be withdrawn from a patient in a
particularly simple manner. Preferably, the catheter system is not open to the
atmosphere. This prevents any contamination of the patient's blood by
bacteria and viruses.
A blood withdrawal port is a closable opening for removing blood. The blood
withdrawal port is embodied as a screw connection with a cover, preferably as
a plug connector with a cover, and particularly preferably as a component that
can be pierced through. The piercable material is made of a tough material
such as plastic, preferably gel. The piercable component can be pierced by a
needle and preferably closed again as soon as the needle is pulled out.
The device preferably has a catheter system that can be connected to a
reservoir that has a movable piston. By this means, pharmaceuticals can be
administered to a patient in a particularly simple manner.
The reservoir with movable piston is a cavity for receiving substances. The
substances can preferably be moved from the cavity by means of the movable
piston. The reservoir with movable piston is preferably a syringe. The syringe
is preferably provided with a thread on its end. In this way, the syringe can
be
replaced. The syringe preferably has glass components, and it is particularly
preferred that the syringe is made of plastic.
The device preferably has a catheter system that can be connected to a
calibration or zero adjustment device. This allows a compensating pressure
on the pressure transducer to be generated.
The calibration device is preferably a bypass stopcock with a least two
connectors. One of the connectors is preferably connected to the catheter
system. The second connector is preferably open to the atmosphere. The
bypass stopcock can preferably be put into different positions, wherein the
catheter system is preferably connected to the atmosphere in at least one of
the positions. It is particularly preferred that the calibration device has a
third
connector to which a safety valve is preferably connected. In the position of
the bypass stopcock in which the catheter system is connected to the
atmosphere, the pressure transducer is exposed to atmospheric pressure so
that it can be calibrated. There are special pressure sensors which are so
accurate by default that calibration with a special calibration device i not
necessary.
The device preferably has a catheter system that can be connected to a
safety valve. By this means, the device can be closed in a simple manner.
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The safety valve is a vaive with which a flow in the device can be limited;
when injecting, in particular, any reflux into the flush bag can thus be
prevented.
The safety valve is preferably provided with a flushing capillary. This
ensures
continuous flushing of the device, in particular with fluids such as NaCI
solution, and also allows the administration of fluid.
The device preferably has a catheter system that can be connected to a drip
chamber.
The drip chamber is a device for channeling fluids and which preferably
interrupts the fiim of fluid. The drip chamber is a container with preferably
two
connectors. A drip generator is preferably connected to the first connector.
The fluid is preferably introduced dropwise into the drip chamber by the
droplet generator. The fluid is preferably collected in the drip chamber. The
fluid is preferably dispensed again from the drip chamber.
The device preferably has a catheter system that can be connected to a flush
bag. In this way, it is possible to flush the device in a simple manner by
means of a flushing solution device.
The flushing solution device is preferably a syringe pump, particularly
preferably a pressurized flush bag or bottie.
The flush bag is a bag that is preferably adapted to receive a flushing
solution.
The flush bag consists preferably of plastic, particularly preferably of
transparent plastic. This enables the filling level to be seen. The flush bag
preferably has at least one connector for connecting it to other components.
The flush bag is preferably deformable and pressure is pneumatically applied
to it by means of a surrounding hollow bag. By this means, fluid can be
dispensed from the flush bag without another fluid having to be added.
The invention shall now be described with reference to the attached Figures,
in which
Fig. I shows a cross-section of a three-way stopcock according to the
invention, in a first position;
Fig. 1 a shows a side view of the switching mechanism of the three-way
stopcock shown in Fig. 1;
Fig. 2 shows a cross-section of the inventive three-way stopcock shown
in Fig. 1, in a second position;
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Fig. 3 shows a cross-section of the inventive three-way stopcock shown
in Fig. 1, in a third position;
Fig. 4 shows a cross-section through a second embodiment of a three-
way stopcock according to the invention;
Fig. 4a shows a side view of the switching mechanism of the three-way
stopcock shown in Fig. 4;
Fig. 5a shows a cross-section through a third embodiment of a three-way
stopcock according to the invention, in the first position;
Fig. 5b shows a cross-section through the third embodiment of the three-
way stopcock according to the invention, in the second position;
and
Fig. 5c shows a cross-section through the third embodiment of the three-
way stopcock according to the invention, in the third position;
Fig. 5d shows a side view of the switching mechanism of the three-way
stopcock shown in Figs. 5a, 5b and 5c;
Fig. 6 shows a schematic view of a monitoring catheter set;
Figs. 7a-c show a schematic illustration of a fourth embodiment of the three-
way stopcock;
Figs. 8a-c show a schematic illustration of a fifth embodiment of the three-
way stopcock;
Fig. 9 shows a cross-section through a schematic illustration of a sixth
embodiment of the three-way stopcock;
Figs. 10a-b show views of a lever;
Figs. 11 a-b show views of a second lever;
Fig. 12a-d show views of a slide mechanism;
Fig. 13a-d show views of a mechanism for turning the halves of the housing
counter to each other and
Figs. 14a-f show views of a rocker switch.
Fig. 1 shows a three-way stopcock in a first position. Three-way stopcock I
has a housing 70 of annular cross-section and made of plastic. The diameter
of housing 70 is 6 mm. Housing 70 has three connectors 10, 20, 30. The three
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connectors 10, 20, 30 lie in the same cross-sectional plane. The first and
second connectors 10, 20 lie opposite one another. The third connector 30
lies on the cross-section of the housing and in a position of 900 rotation
relative to the two other connectors.
The first connector is provided for connection to a catheter 15. Here,
catheter
15 is an arterial catheter 15 which can be introduced into a patient's artery
using the Seldinger technique.
This involves puncturing the artery at the respective place (e.g. in the neck,
leg or arm) with a kind of temporary needle or trocar. After removing the
needle, the actual wire is inserted via the plastic tube that now located in
the
blood vessel. The tube is then removed in such a way that the guide wire
remains in its intravenous position. The arterial catheter is now inserted
over
the wire into the blood vessel. The guide wire is then removed and the
catheter is flushed.
The second connector 20 is connected to an infusion 25. Here, the infusion 25
is a saline solution.
The third connector 30 is connected to a pressure transducer 35.
A switching mechanism 80 is located inside housing 70. The cross-section of
switching mechanism 80 is circular. Switching device 80 abuts on the inner
side of housing 70 an. It has a first channel 40 which is embodied as a
through hole which extends transversely through switching mechanism 80. In
the position shown in Fig. 1, the first channel 40 connects the first
connector
to the second connector 20. The cross-section of channel 40 is the same
throughout and corresponds to the cross-section of the first and second
connectors 10, 20.
The second channel 50 is embodied as a recess in switching mechanism 80.
The second channel 50 extends in the circumferential direction on switching
mechanism 80 and has a dilation 51 at one end, as can be seen in Fig. 1a. In
the position shown in Fig. 1, the second channel 50 lies against the third
connector 30. The third channel 60 is embodied as a lasered capiliary. It
extends from the dilation of the second channel 50, past the first channel 40
to the outer surface 81 of switching mechanism 80.
In the position shown in Fig. 1, catheter 15 is connected to infusion 25. The
third connector 30 to pressure transducer 35 is closed.
In this position, fast flushing of the three-way stopcock 1 with saline
solution is
carried out. In this position, a blood sample could also be taken on the
infusion side. To this end, a blood withdrawal means flushed with 30 ml/hr is
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provided on the infusion line. In addition, insertion of the guide wire into
the
arterial catheter using the Seldinger technique can be carried out in this
position.
Fig. 2 shows the three-way stopcock 1 of Fig. 1 in a second position. In
relation to the position shown in Fig. 1, switching mechanism 80 has been
turned 45 anti-clockwise about its own axis. The first connector 10 and the
third connector 30 are connected by a second channel 50. The third channel
60 connects the third connector 30 to the second connector 20.
In this position, a pulse contour analysis is carried out. Pulse contour
analysis
is a method for determining the cardiac volume. The arterial blood pressure is
measured over time, from which the stroke volume of the heart is then
computed. In order to perform this method with valid results, it is essential
that
the derived pressure curve is of good quality. In the position shown in Fig.
2,
the pressure transducer is connected to catheter 15. The mean pressure in
catheter 15 is 100 mm Hg. A saline solution flows through the third channel 60
from infusion 25 to pressure transducer 35. The pressure in infusion 25 is 300
mm Hg, which means that the saline solution is able to flow through the three-
way stopcock 1 into the blood. The formation of deposits is prevented
because the saline solution continuously flushes the three-way stopcock 1
during realistic pressure measurement.
The cross-section of the third channel 60 is so thin that less than 5 ml of
saline solution per hour flows through it. This amount is so small that it has
no
effect on pressure measurement.
Since pressure transducer 35 is located immediately adjacent the three-way
stopcock 1, any effects of tubing on pressure measurement are prevented. In
this way, pressures are measured very accurately and precisely.
In Fig. 3, the three-way stopcock I is shown in a third position. In this
position,
switching mechanism 80 is tumed 45 clockwise in comparison to the position
shown in Fig. 1. The second channel 50 connects the third connector 30 to
the second connector 20. The first connector 10 is closed.
In this position, the zero adjustment of the pressure transducer is carried
out
by opening the latter to the atmosphere.
In Figs. 4 and 4a, a second embodiment of the three-way stopcock 1
according to the invention is shown. Here, a third channel 61 embodied as a
groove runs on the outer surface 81 of switching mechanism 80. As can be
seen in Fig. 4a, it runs from the dilation of the second channel 50, around
the
first channel 40 and then in the circumferential direction of switching
mechanism 80.
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Here, the third channel 61 has a particularly small cross-section. Due to the
small channel being provided on the outer surface 81 of switching mechanism
80, it is nevertheless possible to produce switching mechanism 80 in a simple
manner as a molded plastic part.
Fig. 5a shows a cross-section through a third embodiment of a three-way
stopcock 1 according to the invention, in the first position. In deviation
from
the embodiment shown in Figs. 4 and 4a, the second channel 52 is embodied
here not as a recess in switching mechanism 80, but as a through hole. The
second channel 52 runs parallel to the first channel 40. As in the previous
embodiments, the second channel 52 is connected to capillary 61.
In the first position, both openings 53 of the second channel 52 abut on the
inner side of housing 70. The second channel 52 is closed.
Fig. 5b shows a cross-section through the third embodiment of the three-way
stopcock 1 according to the invention, in the second position. Here, switching
mechanism 80 is tumed 45 anti-clockwise, with the result that the second
channel 52 connects the first connector 10 to the third connector 30.
As in the embodiments described in the foregoing, the pressure can be
measured in this position. It is possible to carry out continuous flushing of
the
second channel 52 via capillary 61. The flow volume channeled through
capillary 61 is 3 mI/hr.
Fig. 5c shows a cross-section through the third embodiment of the inventive
three-way stopcock 1 in the third position. Here, switching mechanism 80 is
tumed 45 clockwise, with the result that the second channel 52 connects the
third connector 30 to the second connector 20.
As in the embodiments described above, it is possible in this position to
carry
out zero adjustment of pressure transducer 35.
Due to the second channel 52 being embodied here as a through hole, the
sealing regions of the second channel 52 between switching mechanism 80
and housing 70 have been reduced in size. This makes it even simpler to
prevent the formation of deposits in the sealing regions of channel 50.
Figure 5d shows a side view of the switching mechanism of the three-way
stopcock shown in Figures 5a, 5b and 5c. Here it is shown how the third
channel is guided from the second channel (52) around the first channel (40).
Figure 6 shows a schematic view of a monitoring catheter set 90. The
monitoring catheter set 90 has a sensor catheter or catheter system 100,
which includes a three-way stopcock 1, a catheter tube 110 connected to the
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first connector 10 of the three-way stopcock 1, and a pressure transducer 35.
A plug connector 36 is connected by cable 37 to pressure transducer 35.
Monitoring catheter set 90 also has a flushing and blood removal device 120.
The flushing and blood removal device 120 has a first tube line 125, a blood
withdrawal port with silicone membrane 130, a syringe 135, a retaining plate
145 provided with a calibration device 140 having a hydrophobic seal 150, a
safety valve provided with a flushing capillary 155, a second tube line 160, a
drip chamber 165 and a flush bag 170. A first end of the first tube line 125
is
connected via a Luer cone connector to the second connector 20 of the three-
way stopcock 1. The blood withdrawal port with silicone membrane 130 is
connected to the first tube line 125. Seen from the three-way stopcock I
behind blood withdrawal port 130, syringe 135 is connected to the first tube
line 125. The second end of the first tube line 125 is connected to the
calibration device 140. The calibration device 140 is fixed to retaining plate
145, which is located at the level of the patient's heart. Compensation device
140 is provided with a hydrophobic seal 150. A second tube line 160 is
connected to calibration device 140. The safety valve with flushing capillary
155 is connected to said tube line.
Seen from calibration device 140, drip chamber 165 is provided behind safety
valve 155 on the second tube line 160. Flush bag 170 is connected to drip
chamber 165. A pressure of 300 mmHg is applied to the flush bag.
Continuous measurement of the pressure of a patient's pulse can be carried
out using the monitoring catheter set when the three-way stopcock 1 is in a
second switching position. During pressure measurement, the monitoring
catheter set is continuously flushed with a solution placed in flush bag 170.
Pressure transducer 35 may be coupled to and decoupled from catheter tube
110 by means of the three-way stopcock 1 and can be calibrated when the
three-way stopcock 1 is in the third switching position. To calibrate pressure
transducer 35, the three-way stopcock 1 is firstly brought into its third
position.
After that, the second tube line 160 on calibration device 140 is opened to
the
atmosphere. Atmospheric pressure is applied as a result to pressure
transducer 35.
In the first switching position of the three-way stopcock 1, blood can be
withdrawn through blood withdrawal port 130. In this switching position,
pharmaceuticals may be administered to the patient by means of syringe 135.
In order to use monitoring catheter set 90, sensor catheter 100 is put in
place
by means of guide wire, in accordance with the Seldinger technique. When
this is being done, the three-way stopcock 1 is in the first switching
position.
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The flushing and blood removal device 120 is then connected to sensor
catheter 100.
The formation of deposits is prevented due to the continuous flushing of
monitoring catheter set 90.
Because pressure transducer 35 is provided close to the patient, and the
pressure signals are not attenuated by soft components, the pressures in
catheter 110 are measured with particular accuracy and precision.
Due to a blood withdrawal port 130 and a syringe 135 being provided on
monitoring catheter set 90, is it possible in a simple manner to withdraw
blood
from the patient and to supply pharmaceuticals to the patient.
Fig. 7 shows an embodiment of the three-way stopcock in which the third
channel 65 is embodied as a U-shaped groove in the outer surface 81 of
switching mechanism 80. The two parallel regions 66, 67 of the U-shaped
third channel 65 also run parallel to the tuming axis of switching mechanism
80. The first parallel region 66 of the third channel 65 and the second
channel
50 form an V. The second channel 50 is embodied as a recess in switching
mechanism 80 and extends in the circumferential direction on switching
mechanism 80.
Because the first parallel region 66 of the third channel 65 and the second
channel form an "L , it is possible to flush the three-way stopcock in such a
way that flushing solution runs directly over pressure transducer 35.
In the embodiment of the three-way stopcock shown in Fig. 8, the third
channel is embodied as a glass capillary 63. Connector 20 is guided via a
groove perpendicularly into a different plane and is connected to a through
hole. Said through hole contains glass capillary 63. On the opposite side,
glass capillary 63 is connected via a C-shaped groove to connector 30.
In the embodiment shown in Figure 9, the capillary is realized as a lasered
hole 64 in a web. In this embodiment, fast flushing can be realized by having
the flushing solution flow over the web. This fast flushing can be triggered
by
actuating a sealing element that can be operated externally by means of a
rubber operating lever 180. Due to use of rubber operating lever 180,
permanent actuation of the fast flushing is not possible. This prevents any
potential mistakes by users.
Continuous flushing runs through the pot of the three-way stopcock. The
infusion is channeled via a groove which runs parallel to the axis of the
three-
way stopcock. Due to the reduced cross-section in the grooves, the rate of
flushing in the grooves is reduced.
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The three-way stopcock can be operated in several ways. In Figures 10a and
10b, a lever for operating the three-way stopcock is shown.
Figures 11 a and 11 b show another embodiment of a lever for operating the
three-way stopcock. Figures 12a-d show a slide mechanism with which the
valve can be turned by means of a gear rack or similar.
Figures 13a-d show a housing that can be separated by turning the housing
halves counter to each other. By tuming the housing halves, the various
switching positions are realized.
Figures 14a-f show a rocker switch for operating the three-way stopcock. This
rocker switch converts a linear movement into a rotatory movement, thus
operating the valve.
List of reference signs
1 Three-way stopcock
First connector
Catheter
Second connector
Infusion
Third connector
Pressure transducer
36 Plug connector
37 Cable
First channel
Second channel
51 Dilation
52 Second channel
53 Opening of the second channel
Third channel
61 Third channel
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63 Glass capillary
64 Lasered hole
65 Third channel
66 First parallel region
67 Second parallel region
70 Housing
80 Switching mechanism
81 Cuter surface
90 Monitoring catheter set
100 Sensor catheter
110 Catheter tube
120 Flushing and blood removal device
125 First tube line
130 Blood withdrawal port
135 Syringe
140 Calibration device
145 Retaining plate
150 Hydrophobic seal
1 55 Flushing capillary
160 Second tube line
165 rip chamber
170 Flush bag
