Note: Descriptions are shown in the official language in which they were submitted.
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INTUBATION SYSTEM
BACKGROUND OF THE INVENTION
1. Field of The Invention
Applicant's invention relates to endoscopy and to
instruments and methodologies which are useful in the
performance of intubation procedures.
2. Background Information
Intubation is the process by which an endotracheal tube is
inserted into the trachea of an individual who requires
assistance in breathing. The need for intubation often arises
from a cardiac and/or pulmonary arrest, or from trauma when the
patient is unable to breath without outside intervention.
Alternatively, elective intubation may be involved in preparing
a patient for surgery under general anesthesia when the
capacity for independent breathing will be interrupted.
Intubation is a well-established procedure for obtaining
an artificial airway, but is often difficult for the medical
professional, and potentially dangerous (or, at least,
ineffective) for the patient. Properly negotiating the anatomy
of the pharynx and larynx to ultimately place an endotracheal
tube in the trachea for a proper intubation necessarily
requires that the endotracheal tube pass through a patient's
vocal cords, not a structure that is always visible at the time
of intubation, and thus intubation is often a partially blind
procedure that relies on imperfect, indirect methods for
confirming proper endotracheal tube placement.
A laryngoscope is an instrument held with the left hand
during intubation, and is used to divert the patient's tongue
and epiglottis, thereby distorting the anatomy to expose the
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vocal cords. Exposing the vocal cords makes an intubation
(where the endotracheal tube must pass through the vocal cords
and enter the trachea) at least possible. Often, however, even
with the laryngoscope in an optimal position, the vocal cords
cannot be visualized due to a small mouth opening, inability to
flex the neck due to trauma or other reasons, or an anterior
position of the larynx, and, therefore, placement of the
endotracheal tube becomes a partially blind procedure. In
fact, the most critical phase of intubation is that where the
endotracheal tube is seen passing through the vocal cords and
into the trachea. Without seeing this, an intubation becomes
more difficult and may even be impossible.
In any event, absolute certainty of the proper placement
of the endotracheal tube in the trachea is an indispensable
requirement of every intubation. Thus, even if the vocal cords
can be visualized and the endotracheal tube is seen passing
through the vocal cords and into the trachea, indirect methods
for verifying proper placement of the endotracheal tube are
required to assure that the endotracheal tube is in proper
position within the trachea, that being 2.5 to 3.0 cm above the
carina.
Methods for insuring proper endotracheal tube placement,
and thereby excluding an esophageal intubation (where the
endotracheal tube extends into the esophagus, rather than the
trachea) are not always reliable. Even the most reliable
indirect methods for verifying a tracheal intubation are
undesirably time consuming, expensive, and can be associated
with incidental risks (such as by radiation exposure).
The most commonly employed indicator for proper placement
of an endotracheal tube involves listening to the upper abdomen
and chest for breath sounds as the patient is ventilated. Such
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apparent indications of proper endotracheal tube placement
have, however, been reported in cases which ultimately turned
out to involve esophageal intubations.
Another indirect method for verifying proper placement of
an endotracheal tube involves measuring carbon dioxide
emissions from the endotracheal tube (to indicate that the
endotracheal tube is in communication with the patient's lungs
and, therefore, in a position for exhausting the carbon dioxide
of respiration). The carbon dioxide detection method involves
l0 the expense of a disposable carbon dioxide sensor, and is
susceptible to both "false positives" and "false negatives"
under certain circumstances relating to the patient's gastric
state and/or cardiac function at the time of intubation.
Another method of determining proper placement of an
endotracheal tube is by x-ray verification. This involves
radiation exposure which should be avoided when non-radiation
methods are equally efficacious. Moreover, x-ray verification
of proper endotracheal tube placement is time consuming and
involves additional expense.
In light of the limitations to indirect, post-intubation
indication of proper endotracheal tube placement, it is highly
desirable to insure that proper tracheal intubation has
occurred in the first place, and even more desirable to confirm
proper placement as the intubation is proceeding. Absolute
assurance of correct endotracheal tube placement is only
possible when the medical professional can actually watch the
tube pass through the vocal cords and into the trachea, and see
its position in the trachea.
Visualization of the path through which an endotracheal
tube must pass in connection with an intubation is known (See
Fiberoptic Endoscopy and the Difficult Airway, Ovassapian,
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Andranik (Lippincott-Raven)). However, no existing instrument
permits visualization of the intubation process itself, as it
proceeds. Also, existing endoscopes are not specifically or
exclusively designed for intubation and can be difficult to use
by other than highly trained and experienced practitioners of
intubations. According to Dr. Ovassapian, two methods for so
called fiberoptic endoscopy are presently available: the "tube-
first" approach, and the "scope-first" approach.
In the tube-first approach to fiberoptic intubation, an
intubating airway (a temporary device that is placed in the
patient's mouth to guide an endotracheal tube generally toward
its intended target) is placed, and an endotracheal tube is
then inserted into the passageway of the intubating airway.
While a second person supports the endotracheal tube, which is
now held in position by the intubating airway, the fiberscope
is advanced (using both hands) through the endotracheal tube
through the vocal cords and into the trachea. Using the
fiberscope as a guide wire, one of the medical professionals
then advances the endotracheal tube over the fiberscope and
(hopefully) into the trachea. The long fiberscope insertion
cord is then withdrawn while, holding the endotracheal tube in
place.
The tube-first approach to fiberoptic intubation using
presently available apparatuses is not without its limitations.
A common problem may occur when the fiberscope is advanced
through the endotracheal tube. As the distal tip of the
fiberscope nears the distal end of the endotracheal tube, the
fiberscope tip may (and often does) pass through the "Murphy's
eye" of the endotracheal tube. The Murphy's eye is a lumen
which opens through the side of the endotracheal tube near its
distal end which is provided for preventing complete blockage
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of the endotracheal tube, even if the distal opening somehow
becomes blocked. When the fiberscope tip does pass though the
Murphy's eye, withdrawing the fiberscope after placement of the
endotracheal tube is often impossible, unless the endotracheal
5 tube is also withdrawn. Withdrawing the endotracheal tube
under these circumstances is, on occasion, impossible without
substantial trauma to the patient. Maneuverability of the
endotracheal tube/fiberscope combination is severely hampered,
and the combined cross sectional dimension of the two entangled
items near their terminal ends is substantially larger than can
be safely withdrawn from the patient. Whatever the
complications associated with this event, precious time is
consumed, and the objective of rapidly and accurately
establishing, what in many cases is a life saving airway, will
be delayed or even prevented. Furthermore, the pliable
insertion cord of presently available fiberscopes can be easily
displaced by the stiffer endotracheal tube, and the
endotracheal tube may, therefore, be placed in the esophagus,
even though the fiberoptic scope was initially in the trachea.
In the scope-first approach, the medical professional
first attempts to direct the fiberscope, with an endotracheal
tube pre-loaded back on the most proximal segment of the
insertion cord, fully into the trachea, after which the
endotracheal tube is, as described before, advanced over the
fiberscope, using the fiberscope essentially as a guide wire,
into the trachea. This approach reduces the likelihood of
accidentally extending the fiberscope tip through the Murphy's
eye of the endotracheal tube, but exacerbates the limitations
of the fiberscope to act as a guide wire. The fiberscopes of
, the prior art are often simply too flexible to reliably act as
a guide wire type device for shepherding the endotracheal tube
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to its intended position in the trachea relative to the carina.
This is true, in part, because the fiberscope must, over a
longer and more curved path than involved in the tube-first
approach, deflect and conform the advancing endotracheal tube,
against a certain degree of rigidity of its own, to traverse
the pathway to the trachea. A lack of sufficient or moldable
rigidity of the fiberscope often makes it quite difficult to
direct the fiberscope along the intended pathway, even though
the practitioner can see where the fiberscope is going.
In both the tube-first approach and the phases of the
scope-first approach, during which the endotracheal tube is
advanced over the fiberscope, the distal margins of the
endotracheal tube may still impinge on laryngeal anatomy and be
incapable of being advanced into the trachea, in part, because
the highly flexible fiberscope, even if properly placed, may
not be able to resist the deviating forces which act against
the endotracheal tube. Also, during any phase of an intubation
procedure where one attempts to advance an endotracheal tube
over an already-placed fiberscope, there may be a tendency to
inadvertently pull the fiberscope back from its proper position
as the endotracheal tube is advanced, thereby resulting in an
esophageal intubation or other complications. This is true
particularly because two practitioners are necessarily involved
in presently known fiberoptic intubation procedures, and
perfect coordination between the two, to detecting the lack
thereof in the often hectic environment of a difficult
intubation, for example, is not always possible.
The need for two practitioners for performing fiberoptic
endoscopy in the context of intubation procedures arises, in
part, from the fact that available fiberscopes and endotracheal
tubes are not truly designed to be used together. Presently
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available fiberscopes include features which are unnecessary
for intubation purposes -- auxiliary channels for transporting
irrigation fluids, for fluid evacuation, or even for biopsy
work. Their length far exceeds that of the endotracheal tubes
with which they may be used, thus making possible the Murphy's
eye entanglement problem described above. As already
mentioned, presently available fiberscopes lack a sufficient
degree of rigidity to retain a desired configuration which
would be most helpful in manipulating the fiberscope and
endotracheal tube as one unit and insuring that the fiberscope
(and the loaded endotracheal tube) will follow a desired path
shape which ends in the trachea. Finally, the complexity of
full-function fiberscopic systems (largely the result of
unnecessary features for intubation purposes? makes the units
difficult to use and the associated intubation unnecessarily
difficult to complete.
It would well serve medical professionals and their
patients to have available a single device which addresses the
deficiencies of equipment which is presently used to perform
intubation, and could be employed using the standard hand
motions that are generally well known by most practitioners who
perform routine intubations. The effect would be to simplify
intubation and thereby increase the probability that each
intubation will proceed properly, swiftly, and safely.
The beneficial characteristics of an improved intubation
system would arise from a uniquely configured fiberscope. The
fiberscope would be of a new design, compared to currently
known fiberscopes, and includes an insertion cord which is
configured to prevent extension of its distal tip beyond the
distal end of an endotracheal tube fitted thereon. To enhance
the directional control of the fiberscope (e.g. enabling the
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direct translation of the user's hand movements to the distal
portions of the fiberscope), and to bolster its ability to pass
anatomical features which would otherwise tend to divert the
fiberscope in an undesirable direction, or interfere with the
endotracheal tube's following of the fiberscope, the insertion
cord would be modified from currently available examples. The
insertion cord would include a malleable, rigidity enhancing
member which will endow it both with the rigidity which is
desirable, to aid in controllably advancing the cord along its
intended path and the shape memory which will allow the user to
form segments of its length to conform to the pathway which it
must traverse during the intubation. In the absence of
irrigation and evacuation channels and similar unnecessary
features of present fiberscope models, the newly designed
fiberscope would be easier to clean and maintain, and likely be
available at a lower cost. It could also be made to exhibit a
smaller cross section and thus be suitable for a wider range of
endotracheal tube sizes, including those for pediatric use.
The fiberscope, designed according to the present
invention, is what might better be described as an endotracheal
tube "Endoscopic Stylet" for it serves both functions of a
fiberoptic endoscope for visualization and manipulation of the
intubation procedure and those of a stylet to help conform the
endotracheal tube to any configuration for somewhat forcibly
advancing the apparatus along a desired path, even against
resistance from existing anatomical features. Because of these
features, and the fact that the endoscopic stylet and its
intended endotracheal tube mate would be of approximate equal
length and designed for use, relative to each other, as static
components of a single unit during an intubation procedure, the
system would be used by a single practitioner. Adding the
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feature of an remotely-controlled, articulating terminal
segment for the insertion cord of the endoscopic stylet would
enable the practitioner to maneuver the distal end of the
associated endotracheal tube which is fitted thereon, thus
further enhancing the ease of use and reliability of the
endoscopic stylet system.
No existing instrument allows its user to visualize the
precise position of the distal end of the endotracheal tube
relative to surrounding anatomy as the endotracheal tube is
being placed, and, by manipulating the end of the insertion
cord, directly affect the orientation of the distal
endotracheal tube end, and thereby guide the endotracheal tube
through the vocal cords.
More specific features of the intubation system of the
present invention will be disclosed in the Detailed Description
of the Preferred Embodiment. In sum, however, the endoscopic
stylet system of the present invention: (1) facilitates
simultaneous advancement of the terminal end of an endotracheal
tube and of a fiberscopic instrument for visualization of such
advancement; (2) permits independent use by a single
practitioner by eliminating unnecessary system bulk and
fiberscope insertion cord length; (3) substantially reduces
likelihood of esophageal intubations and of Murphy's eye
entanglement complications; (4) affords its users remote
controllability of the terminal segments of the endotracheal
tube for ease of maneuvering through action of the associated,
remotely controllable segment of the fiberscopic stylet;
(5) affords greatly enhanced directional control of the distal
portions of the fiberscope; (6) facilitates the negotiation of
anatomical features which would otherwise tend to divert the
fiberscope in an undesirable direction, or interfere with the
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endotrachael tube's following of the fiberscope; and (7)
eliminates inadvertent mis-direction of a previously,
properly-placed fiberscope, as in the case of presently
practiced procedures where an endotracheal tube is
independently advanced over the fiberscope.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a
novel instrumental system for performing intubation
procedures.
It is another object of the present invention to provide
an instrumental system for performing intubation procedures,
which system obviates complications associated with the use of
presently available fiberscopic instruments for intubation
procedures.
It is another object of the present invention to provide
an instrumental system for performing intubation procedures,
which system obviates the complexity, risks and potential
delays associated with "tube-first" or "scope-first"
procedures of the prior art.
It is another object of the present invention to provide
an instrumental system for performing intubation procedures,
which system virtually insures that an esophageal intubation
will not have occurred at the end of the placement phase of
the procedure.
It is another object of the present invention to provide
an instrumental system for performing intubation procedures,
which system simplifies the intubation procedure by combining
stylet or guide wire type functions with the fiberscopic
instrument for diverting or managing anatomical structures
which would otherwise impede progress of the fiberscope and
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permitting the advancement and manipulation, as a unit, of both
the fiberscopic and endotracheal tube components of the system
using the same hand motions as are presently known to most
practitioners who perform intubations.
It is another object of the present invention to provide
an instrumental system for performing intubation procedures
which allows its user to visualize the precise position of the
distal end of the endotracheal tube relative to surrounding
anatomy, and, by manipulating the end of the insertion cord,
directly affect the orientation of the distal endotracheal tube
end, and thereby guide the endotracheal tube through the vocal
cords to a proper position in the trachea.
It is another object of the present invention to provide
an instrumental system for performing intubation procedures,
which system directly verifies proper placement of an
endotracheal tube, not after intubation, but simultaneously
with intubation, thus eliminating wasted time, expense, and/or
radiation exposure involved with presently employed indirect
methods as well as virtually any chance of an improperly placed
endotracheal tube during an intubation procedure.
It is another object of the present invention to provide
an instrumental system for performing intubation procedures,
which system includes a fiberscopic type instrument which is
specifically sized and configured to correspond to the length
of an endotracheal tube with which the fiberscopic instrument
will be used, such that there is little excess insertion tube
length to manage during an intubation, and little, if any,
danger of engaging the distal tip of the fiberscopic instrument
with the Murphy's eye of the endotracheal tube.
In satisfaction of these and related objectives,
Applicant s present invention provides an intubation system
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which is based on newly designed fiberscope design. The
endoscopic stylet of the present invention is designed to
serve, not only as the means for transmitting a visual image of
the anatomical surfaces of the areas through and to which its
distal tip passes during an intubation procedure, but to serve
as a semi-rigid stylet which may be formed into, and hold, a
shape for conforming generally to the contour of the pathway
past which the instrument must pass during the procedure. In
addition to making its passage through the desired pathway
easier because of the option for pre-forming its shape to
correspond to the anticipated pathway contours, this semi-
rigidity characteristic of the "endoscopic stylet" of the
present invention serves the functions of: (1) a stylet for
diverting anatomical features, such as the tongue which might
(even with the help of a laryngoscope) otherwise obstruct the
intubation procedure; and (2) a guide structure for an
endotracheal tube which helps prevent a diversion of the
endotracheal tube from the course defined by the endoscopic
stylet into the trachea, even as against diversionary forces
applied by unfavorable upper airway anatomy (such as a
posteriorly displaced epiglottis due to lymphoid tissue), or by
soft tissue edema, tumors, or unusually pronounced fatty
deposits.
The features designed into the endoscopic stylet of the
present invention, individually and collectively, were selected
specifically for their utility in performing intubation
procedures. Absent from the endoscopic stylet are features
which have no utility for intubations, and, in fact, may hinder
the procedure. Such features include excessive insertion cord
length, the one or more working channels, integral suction and
irrigation systems, cauterizing tips, etc, which are found in
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many non-intubation specific fiberscopic instruments.
Benefits of this selection of features exceed the readily
apparent. The cross sectional size of the insertion cord of
the present endoscopic stylet may, for example, be smaller for
accommodating even the smallest endotracheal tubes with which
the instrument might be used. Also, by not merely adding
features, but eliminating unnecessary ones, the present
instrument is a more cost effective choice for intubation
procedures than instruments of old design. Further, by
l0 reducing the instrument's bulk and complexity, one expands the
group of medical professionals who will more readily be able to
use the instrument from that relatively small group who are
qualified to use presently available endoscopic instruments.
The latter two points -- cost savings and simplicity of use and
operation -- could well translate into saved lives, as the
instrument might well be found in environments which
traditional endoscopic instruments would never be placed, such
as with paramedical field personnel. Further still, cleaning
and maintenance of the endoscopic stylet (without unnecessary
and difficult-to-clean working channels) is much less
time-consuming than instruments of the prior art.
The endoscopic stylet is provided with a remotely
deflectable tip portion. The semi-rigid proximal and middle
portions of the insertion cord of the endoscopic stylet greatly
facilitate maneuvering the distal tip, past the anatomy of the
mouth and throat, into position near the vocal cords. Once in
this position, the user actuates the deflectable tip to orient
it for easy passage through the vocal cords and into the
trachea. Because the endotracheal tube of the present system
is intended to be loaded on the endoscopic stylet during the
entirety of the insertion phase of an intubation procedure, and
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the terminal end of the endotracheal tube is substantially
coextensive with that of the endoscopic stylet, deflecting the
tip portion of the endoscopic stylet effects a like deflection
of the distal portion of the endotracheal tube. The endoscopic
stylet and the associated endotracheal tube as a single unit
become highly maneuverable by one practitioner using the right
hand, while the left hand is maintaining the best possible
exposure by placing the laryngoscope in the standard position.
Thus, the hand motions involved are at least very similar to
those already known and employed by most practitioners
performing standard endotracheal intubations, aided only by a
stylet that puts the operator's eye at the distal end of the
endotracheal tube, and gives the operator the ability to flex
and rotate the endotracheal tube tip.
The endoscopic stylet is configured to correspond to the
length of endotracheal tubes with which the instrument will be
used, thereby eliminating such excess insertion cord length as
would prevent the effective single-handed use of the instrument
if it shared length-wise dimensions of typical fiberscopes of
the prior art. The handle member, which includes the eye piece
for viewing images transmitted from the distal tip of the
endoscopic stylet and thumb controls for manipulating the
divertable distal portion of endoscopic stylet, is compact and
situated immediately proximal to the position of a loaded
endotracheal tube. This means that the user can operate the
endoscopic stylet and endotracheal tube as a single unit
duplicating hand motions that are already known as standard
intubation techniques by most practitioners. The practitioner
need only use the right hand to manipulate the endoscopic
stylet, leaving the left hand to maintain exposure with the
laryngoscope. This obviates the need for a second
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practitioner.
The substantial correspondence between the length of the
insertion cord of the endoscopic stylet with that of the
endotracheal tube reduces the possibility of the endoscopic
5 stylet tip passing through and lodging in the Murphy's eye of
the endotracheal tube. Also, because of the stylet
characteristics of the endoscopic stylet, there is no need for
using an intubating airway, a separate stylet or guide wire,
and no need for performing either a "tube-first" or "scope-
l0 first" type procedure with the inherent delays and chances for
esophageal intubations. Finally, because the user is visually
monitoring the progress of the endotracheal tube as it
progresses toward and through the patient's vocal cords, there
is no need for intubation verification. The real-time visual
15 verification of the endoscopic stylet, which necessarily
carries with it the distal portion of the endotracheal tube as
it passes through the vocal cords and into the trachea, insures
a proper endotracheal tube placement in every instance. One
merely needs to insure that the endotracheal tube not be
inadvertently withdrawn as the endoscopic stylet is withdrawn
at the end of the placement phase of an intubation, just as
this is necessary as a stylet is withdrawn during a standard
intubation.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig 1. is a perspective view of the intubation system of
the present invention.
Fig 2. is a cross sectional view of the insertion cord of
the endoscopic stylet shown in Fig 1. along Line A - A.
Fig 3. is a cross sectional view of the insertion cord of
the endoscopic stylet shown in Fig 1. along Line B - B.
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DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to Figure 1, the intubation system of the
present invention is identified generally by the reference
numeral 10. System 10 includes an endoscopic stylet 12 on
which is fitted an endotracheal tube 14 when system 10 is
configured for use. Endoscopic stylet 12 includes an insertion
cord 16 which is of a length such that the distal insertion
cord tip 18 extends no further than the distal endotracheal
tube tip 20 of the endotracheal tube 14 when fitted on the
insertion cord 16. This correlation between the lengths of the
endotracheal tube 14 and insertion cord 16 effectively prevents
accidental passage of the distal insertion cord tip 18 through
the Murphy's eye 22 of the endotracheal tube 14.
A terminal segment 24 of the insertion cord 16 of the
endoscopic stylet 12 is remotely deflectable using thumb
controls 34 which are positioned adjacent to the handle/eye
piece 26. Remotely deflectable fiberscope tips and the
component mechanisms thereof are known in the art and need not
be discussed here for enabling disclosure purposes (see U.S.
Patent No. 3572325 issued to Bazell). However, the combination
of the deflectable tip feature and the other characteristics of
the present system (the shorter insertion cord 16, for example)
and the associated methodology afford benefits which are not
readily apparent to the casual observer.
Because the present method teaches inserting the insertion
cord 16 with the endotracheal tube 14 loaded thereon, and
because the lengths of the insertion cord 16 and the
endotracheal tube 14 are matched whereby their respective
distal termini are substantially coincident, any deflection of
the distal insertion cord tip 18 should, and, in the case of
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the present system, will, effect a similar deflection of the
corresponding portion of the endotracheal tube 14. Thus, a
user is able literally to maneuver the distal portions of the
endotracheal tube 14 through use of the thumb controls 34 on
handle/eye piece 26. This is in contrast to devices of the
prior art.
Experimentation by the present inventor has revealed that
fiberscopes of old design and configuration cannot provide this
benefit. Because the insertion cords of the prior art are so
long, it has been found impossible to maneuver the distal
portions of an endotracheal tube 14 when aligned with the
distal tip of a conventional fiberscope with deflectable tip
features. The expanse over which the control wires extend so
dampens the mechanical action of the thumb controls, that the
inventor was not able to effectively deflect the distal portion
of an endotracheal tube by actuating the thumb controls of the
conventional fiberscope. Inadequate force is transmitted to
the distal tips of these fiberscopes to deflect the
endotracheal tube.
In the preferred embodiment of intubation system 10, the
handle/eye piece 26 of the endoscopic stylet 12 is situated at
the proximal end 28 of the insertion cord 16 which closely
corresponds to the proximal end 32 of the endotracheal tube 14.
This is in stark contrast to the relative placement of the
handle/eye piece of conventional fiberscopes in which, because
of a great excess in cord length for the fiberscope, the
handle/eye piece is greatly separated from the position of the
proximal end of the endotracheal tube during an intubation. In
addition, the handle/eye piece 26 of the present system 10 is
incorporated into a much more compact unit than comparable
structures in conventional fiberscopes -- this due to the
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relative simplicity of endoscopic stylet 12 of the intubation
system 10 as will be explained hereafter.
The compact structure of the endoscopic stylet 12 (the
combined product of the corresponding lengths of the
endotracheal tube 14 and insertion cord 16, and of a more
compact, simple handle structure) greatly facilitates handling
and fine control of the system 10 during intubation. Existing
units have a great excess of fiberscope insertion cord length
and can be unwieldy by most accounts and require two handed
operation. The endoscopic stylet of the present invention may
be confidently manipulated with a single hand (the right), and
the terminal segment 24 can be controlled using thumb
controls 34.
Referring to Figures 2 and 3, cross sectional views of the
insertion cord 16 of the endoscopic stylet 12 at the two
indicated sites shows a relatively simple structure. Extending
through the length of the insertion cord 16 from the handle/eye
piece 26 to a point near (but not to) the proximal end of the
terminal segment 24 is an elongate rigidity member 36.
2o Rigidity member 36 is, in the preferred embodiment, a
yieldable, shape-retaining metallic rod which endows the
insertion cord 16, and, therefore, the loaded endotracheal
tube 14, with the capacity for retaining curvature formed by
its user prior to insertion during an intubation in order to
conform to the contour of the path which it must traverse
during an intubation. The rigidity member 36 extends, in the
preferred embodiment, from approximately the proximal end of
the insertion cord 16 to a point proximal to the distal
insertion cord tip 18, not inclusive of the remotely
deflectable terminal segment 24. The result is an insertion
cord 16 and endotracheal tube 14, the majority of the length of
CA 02289614 1999-11-15
WO 99/47038 PCT/US98/Z6399
19
which (the "semi-rigid segment") holds a desired shape for
diverting anatomical features, such as the tongue, which could
otherwise impede the intubation procedure.
Also visible from the cross sectional views of Figures 2
and 3 are the light guide cables 38, fiberoptic bundle 40, and
control wires 42 and 44. Light guide cables are a conventional
feature for fiberscopes, and in this case carries light from a
light source (not depicted in the drawings) in or near
handle/eye piece 26 to the distal tip 46 of the endoscopic
stylet 12 for providing light in the area to which the
insertion cord 16 is extended during an intubation procedure.
Control wires 42 and 44 are connected between thumb controls 34
in the handle/eye piece 26 and the deflection mechanisms in the
terminal segment 24 of the insertion cord 16 aenerallv
according to conventional design for such mechanisms. The
fiberoptic bundle 40 is the group of fiberoptic fibers which
carry images from the distal tip 46 of the insertion cord 16 to
the optics of handle/eye piece 26.
Although the invention has been described with reference
to specific embodiments, this description is not meant to be
construed in a limited sense. Various modifications of the
disclosed embodiments, as well as alternative embodiments of
the inventions will become apparent to persons skilled in the
art upon the reference to the description of the invention.
It is, therefore, contemplated that the appended claims
will cover such modifications that fall within the scope of the
invention.