U.S. patent application number 11/523519 was filed with the patent office on 2009-04-30 for systems, methods and apparatus for respiratory support of a patient.
Invention is credited to Lutz Freitag, Gregory Kapust, Anthony Wondka.
Application Number | 20090107494 11/523519 |
Document ID | / |
Family ID | 37889494 |
Filed Date | 2009-04-30 |
United States Patent
Application |
20090107494 |
Kind Code |
A1 |
Freitag; Lutz ; et
al. |
April 30, 2009 |
SYSTEMS, METHODS AND APPARATUS FOR RESPIRATORY SUPPORT OF A
PATIENT
Abstract
Spontaneous respiration is detected by sensors. An additional
amount of oxygen is administered to the lungs via a jet gas current
at the end of an inhalation procedure. Breathing volume, absorption
of oxygen during inhalation, and clearance of carbon dioxide during
exhalation are improved. If required, the exhalation procedure of
the patient can be arrested or slowed by a countercurrent to avoid
a collapse of the respiration paths. An apparatus including an
oxygen pump can be connected to an oxygen source and includes a
tracheal prosthesis that can be connected via a catheter. The
respiration detections sensors are connected to a control unit for
activating the oxygen pump. The tracheal prosthesis includes a
tubular support body with a connection for the catheter, and the
sensors are associated with the support body. The tracheal
prosthesis and jet catheter are dimensioned so the patient can
freely breathe and speak without restriction.
Inventors: |
Freitag; Lutz; (Hemer,
DE) ; Kapust; Gregory; (San Ramon, CA) ;
Wondka; Anthony; (Thousands Oaks, CA) |
Correspondence
Address: |
PATTON BOGGS LLP
8484 WESTPARK DRIVE, SUITE 900
MCLEAN
VA
22102
US
|
Family ID: |
37889494 |
Appl. No.: |
11/523519 |
Filed: |
September 20, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60718318 |
Sep 20, 2005 |
|
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|
Current U.S.
Class: |
128/203.12 ;
128/204.17; 128/207.14; 977/904 |
Current CPC
Class: |
A61M 16/00 20130101;
A61M 2016/0021 20130101; A61M 16/0468 20130101; A61M 2016/0027
20130101; A61M 16/0006 20140204; A61M 16/024 20170801; A61M 16/0465
20130101; A61M 2016/0413 20130101; A61M 16/0063 20140204 |
Class at
Publication: |
128/203.12 ;
128/207.14; 128/204.17; 977/904 |
International
Class: |
A61M 16/00 20060101
A61M016/00 |
Claims
1. An apparatus for supplementing respiration of a spontaneously
breathing patient comprising: an oxygen-bearing gas source, patient
respiration sensors for detecting spontaneous respiration phases of
the patient a catheter adapted to be inserted into the respiratory
system of the patient and fluidly connected to the oxygen-bearing
gas source, and a control unit in communication with the patient
respiration sensors, the control unit adapted and configured to
determine a need for an additional amount of gas based on the
patient's need as determined by a measurement of the patient's
respiration and to control the oxygen-bearing gas source to deliver
a volume of gas to the patient through the catheter in synchrony
with a portion of the patient's spontaneous breathing pattern when
the patient needs respiratory support.
2. The apparatus of claim 1, wherein at least one of the patient
respiration sensors are selected from the group consisting of:
thermistors, pressure sensors, silicone wire strain gauges,
respibands, respitrace, transthoracical electrical impedance
measuring devices, flow sensors at the mouth or nose, and
capnometers.
3. The apparatus of claim 1, wherein the patient respiration
sensors are used for ventilation control and connected to the
control unit wirelessly.
4. The apparatus of claim 1, wherein the catheter is connected to a
low profile tracheal prosthesis configured to be placed within a
trachea without occluding the airway while maintaining tracheal
patency and preventing the respiration sensor from contacting the
tracheal wall.
5. The apparatus of claim 4, wherein the tracheal prosthesis
further comprises prongs or petals that are configured to be
positioned on at least one of an anterior wall of a trachea and or
a neck surface of the patient and to secure the prosthesis in
place.
6. The apparatus of claim 4, wherein the tracheal prosthesis
further comprises an antibacterial, a drug, a lubricious coating,
hydrogel anesthetics, a treatment to prevent granulation tissue, or
a treatment to prevent mucous formation coating.
7. The apparatus of claim 1, wherein the catheter further comprises
a jet nozzle.
8. The apparatus of claim 7, wherein an exit port of the catheter
is substantially centered in the trachea though the use of coils or
bends in the catheter configured to touch the walls of the
trachea.
9. The apparatus of claim 7, wherein the catheter further comprises
clips or balloons adapted to position the catheter in a tracheal
lumen, wherein the clips or balloons are non-obstructive and do not
obstruct an airway when inserted into a tracheal lumen.
10. The apparatus of claim 9, wherein the catheter has a single
circumferential balloon or a plurality of balloons.
11. The apparatus of claim 9, wherein the clips are made of a
resilient material.
12. The apparatus of claim 1, wherein the catheter comprises an
inner lumen and an outer lumen each for gas flow.
13. The apparatus of claim 12, wherein the wall of the outer lumen
comprises a plurality of gas exit ports that are configured to
create airflow profiles in the trachea.
14. The apparatus of claim 13, wherein the plurality of ports are
substantially circular, hexagonal, oval, or slits.
15. The apparatus of claim 13, wherein the catheter further
comprises a flow regulator adapted to regulate the flow of
oxygen-bearing gas through the ports.
16. The apparatus of claim 15, wherein the flow regulator is
selected from the group consisting of: a gliding sheath, shutters,
louvers, and slats.
17. The apparatus of claim 1, wherein the apparatus is a modular
component.
18. The apparatus of claim 1, wherein at least one sensor is a
nanotechnology device.
19. The apparatus of claim 1, wherein oxygen-bearing gas from the
oxygen-bearing gas source further comprises fragrances, aerosolized
drugs, or water.
20. The apparatus of claim 1, wherein oxygen-bearing gas from the
oxygen-bearing gas source is heated.
21. The apparatus of claim 1, wherein the control unit is
configured to determine when a patient's respiration is in need of
mechanical support based on the information received by the control
unit from the respiration sensors.
22. The apparatus of claim 1, wherein the sensors comprise at least
two sensors and the two sensors are disposed at different
locations.
23. The apparatus of claim 22, wherein the sensors comprise a first
and a second sensor, and the first sensor is configured so that a
signal response of a first sensor is dampened relative to a signal
response of the second sensor, and further comprising a logic for
comparing the signal responses of the first and second sensors for
correcting signal drift, transient signals and artifacts.
24. The apparatus of claim 1, further comprising a gas pump
operatively connected to the oxygen-bearing gas source, wherein the
gas pump, oxygen-bearing gas source, and control unit are housed
together.
25. A method for supplementing the respiration of a spontaneously
breathing patient comprising the steps of: inserting a catheter
into the respiratory system of the patient so that the catheter
does not hinder the patient's ability to speak or breathe
spontaneously through the upper airway, determining the phases of
spontaneous respiration of the patient with respiration sensors
including beginning and end of breath phases, administering a
supplemental volume of oxygen-bearing gas based on the patient's
need as determined by a measurement of the patient's respiration to
the lungs at a gas flow speed of greater than 100 m/sec., wherein
the delivery is synchronized with a portion of the patient's
spontaneous respiration phases.
26. The method of claim 25, wherein the supplemental oxygen-bearing
gas is administered simultaneously with a continuous flow of
oxygen-bearing gas.
27. The method of claim 25, wherein the respiration sensors are
selected from the group consisting of: thermistors, pressure
sensors, silicone wire strain gauges, respibands, respitrace,
transthoracical electrical impedance measuring devices, flow
sensors at the mouth or nose, and capnometers.
28. The method of claim 25, further comprising connecting the
catheter to a tracheal prosthesis that is configured to not occlude
an airway.
29. The method of claim 28, further comprising securing the
tracheal prosthesis in a trachea with prongs or petals, wherein the
prongs or petals are positioned on an anterior wall of a trachea
and or a neck surface of the patient and the prongs or petals
secure the prosthesis in place.
30. The method of claim 28, further comprising supplying an
antibacterial, a drug, a lubricious coating, hydrogel anesthetics,
a treatment to prevent granulation tissue, or a treatment to
prevent mucous formation to the patient by providing a tracheal
prosthesis coated thereof.
31. The method of claim 25, wherein the step of inserting the
catheter comprises inserting a catheter having an exit port,
wherein the exit port of the catheter is substantially centered in
the patient's trachea.
32. The method of claim 31, wherein the step of inserting the
catheter having an exit port comprises substantially centering the
exit port of the catheter in the trachea through the use of coils
or bends in the catheter touching the wails of the trachea.
33. The method of claim 31, wherein the step of inserting the
catheter having an exit port comprises substantially centering the
exit port of the catheter in the trachea though the use of clips or
balloons attached to the catheter and the clips or balloons are
configured to not seal or obstruct an airway.
34. The method of claim 33, wherein the step of substantially
centering the catheter comprises substantially centering a catheter
having a single circumferential balloon or a plurality of
balloons.
35. The method of claim 33, wherein the step of substantially
centering the catheter comprises substantially centering a catheter
having clips made of a resilient material.
36. The method of claim 25, wherein the step of inserting the
catheter comprises inserting the catheter into the patient's
respiratory system by way of the mouth or nose.
37. The method of claim 25, wherein the step of inserting the
catheter comprises inserting a catheter having an outer lumen and
an inner lumen, and wherein a wall of the outer lumen comprises a
plurality of gas exit ports that are configured to create airflow
profiles in a trachea.
38. The method of claim 37, wherein the step of administering
comprises administering the oxygen-bearing gas through the inner
lumen during inhalation and administering the oxygen-bearing gas
through the outer lumen during exhalation.
39. The method of claim 25, further comprising applying vibratory
flow to improve mucus clearance.
40. The method of claim 25, further comprising sensing high
pressure in the trachea and shutting off the administration of
oxygen-bearing gas.
41. The method of claim 25, wherein the step of administering a
supplemental amount of oxygen-bearing gas comprises administering a
supplemental amount of oxygen-bearing gas selected from the group
consisting of: substantially pure oxygen, mixtures of oxygen and
nitrogen, mixtures of oxygen and inert gases, ambient air, and
various combinations thereof.
42. The method of claim 41, wherein the step of administering a
supplemental amount of oxygen-bearing gas further comprises
administering a supplemental amount of oxygen-bearing gas
comprising fragrances, aerosolized drugs, or water.
43. The method of claim 41, further comprising heating the
oxygen-bearing gas.
44. The method of claim 25, further comprising determining when the
patient's respiration is in need of mechanical support, based on
information received by the control unit from the breath
sensors.
45.-59. (canceled)
60. A method for supplementing the respiration of a spontaneously
breathing patient comprising the steps of: inserting an
oxygen-bearing gas delivery device into the respiratory system of
the patient, detecting spontaneous respiration of the patient with
respiration sensors, identifying an inhalation phase and an
exhalation phase using information from the respiration sensors,
synchronizing delivery of a volume of oxygen-bearing gas based on
the patient's need as determined by a measurement of the patient's
respiration to the patient during an inhalation phase to augment
inspiration or during an exhalation phase to augment exhalation,
and wherein the delivered volume of the oxygen-bearing gas is
increased, decreased, switched-on or switched-off based on feedback
from the respiration sensors.
61. A device for supplementing the respiration of a spontaneously
breathing patient comprising sensors for monitoring the spontaneous
respiration of the patient a catheter configured to be inserted
into the respiratory system of the patient, a control unit
communicating with the sensors configured to identify an inhalation
and an exhalation phase of the patient's spontaneous respiration
and the need for supplemental gas volume based on the patient's
need as determined by a measurement of the patient's respiration
wherein the control unit is further configured to administer a
supplemental amount of oxygen-bearing gas through the catheter
synchronously with either an inhalation phase or an exhalation
phase, and wherein the supplemental volume of the oxygen-bearing
gas is increased, decreased, switched-on or switched-off based on
feedback from the sensors.
62. A system for supplementing the respiration of a spontaneously
breathing patient, comprising: a transtracheal catheter adapted for
placement in an airway of a patient and comprising at least one
respiration sensor, wherein the transtracheal catheter is
configured to not obstruct an airway of the patient; and a wearable
mobile respiratory device comprising: a control unit in
communication with the respiration sensor, the control unit
configured to determine the need for additional volume based on the
patient's need as determined by a measurement of the patient's
respiration and to control the delivery of a volume of supplemental
gas to the patient in synchrony with a portion of the patient's
spontaneous breathing pattern when the need for breath augmentation
is determined.
63. The system of claim 62, wherein the catheter is connected to a
tracheal prosthesis configured to be placed within a trachea
without occluding the airway while maintaining tracheal patency and
preventing the respiration sensor from contacting the tracheal
wall.
64. The device of claim 61, wherein the supplemental volume of
oxygen-bearing gas is administered at a gas flow speed of greater
than 100 m/s.
65. The device of claim 61, wherein the supplemental volume of
oxygen-bearing gas is administered at a gas flow speed of between
about 100 m/s to about 300 m/s.
66. The method of claim 60, further comprising: determining at or
near a peak of the inhalation phase whether the volume of
oxygen-bearing gas is needed by the patient.
67. The method of claim 60, further comprising: determining at or
near a peak of the exhalation phase whether more carbon dioxide
needs to be exhaled by the patient.
68. The method of claim 60, further comprising: detecting gas
composition in the airway to determine whether to adjust the
delivery of the supplemental volume of oxygen-bearing gas.
69. The apparatus of claim 1, wherein the control unit is
configured to determine a need for additional volume of gas based
on input from the patient respiration sensors and is further
configured to control the oxygen-bearing gas source to increase,
decrease, switch-on or switch-off the delivery of the volume of gas
based on the need determined.
70. The method of claim 44, wherein the step of administering a
supplemental amount of oxygen-bearing gas comprises administering a
supplemental amount of oxygen-bearing as to the lungs when the
patient is in need of mechanical support.
71. The method of claim 44, further comprising providing a
continuous flow of oxygen-bearing gas in addition to administering
a supplemental amount of oxygen-bearing gas.
Description
PRIORITY CLAIM
[0001] This patent application claims priority to U.S. Ser. No.
60/718,318, "Systems, Methods and Apparatus for Respiratory Support
for a Patient", filed Sep. 20, 2005, which is incorporated herein
by reference in its entirety.
FIELD OF INVENTION
[0002] The present invention relates generally to respiratory
systems and more particularly to specialized systems, methods, and
devices for enhanced ventilation of a patient.
BACKGROUND OF THE INVENTION
[0003] In order for the body to take in oxygen and give off carbon
dioxide, two components of the respiratory bronchial system must
function--the lungs as a gas-exchanging organ and the respiratory
pump as a ventilation organ that transports air into the lungs and
back out again. The breathing center in the brain, central and
peripheral nerves, the osseous thorax and the breathing musculature
as well as free, stable respiratory paths are necessary for a
correct functioning of the respiratory pump.
[0004] In certain diseases there is a constant overload on or
exhaustion of the respiratory pump. A typical syndrome is pulmonary
emphysema with flat-standing diaphragms. Flat-standing diaphragms
do not have the ability to contract. In the case of pulmonary
emphysema, respiratory paths are usually extremely slack and tend
to collapse. As a consequence of the flattened, over-extended
diaphragms, the patient cannot inhale deeply enough. In addition,
the patient cannot exhale sufficiently due to collapsing
respiratory paths. This results in an insufficient respiration with
an undersupply of oxygen and a rise of carbon dioxide in the blood,
i.e. a ventilatory insufficiency.
[0005] The treatment for inhalation difficulty often involves a
breathing device. A home ventilator is an artificial respirator for
supporting or completely relieving the respiratory pump. Artificial
respiration can be applied non-invasively via a nose or mouth mask
that the patient can put on and take off as needed. However, the
nose or mouth mask prevents the patient from breathing and speaking
freely, and is very invasive.
[0006] Another treatment option is invasive ventilation. Invasive
ventilation is usually applied via a cuffed endotracheal tube that
is passed through the mouth and the larynx and into the windpipe,
or is applied via a tracheostomy. The tracheostomy involves an
opening placed in the trachea by an operation. A catheter about the
diameter of a finger with a blocking balloon or cuff is inserted
via the opening into the trachea and connected to a ventilator that
applies cyclic positive pressure. This procedure makes sufficiently
deep respiration possible, but prevents the patient from
speaking.
[0007] In addition to home ventilation with a mask and invasive
ventilation, there is also transtracheal administration of oxygen
via thinner catheters. U.S. Pat. Nos. 5,181,509 or 5,279,288
disclose corresponding embodiments. In this manner, a highly dosed
administration of oxygen is administered to the patient in a
continuous stream with a permanently adjusted frequency. The flow
rate of oxygen is regulated manually by a regulator. However,
simulation of the natural breathing process of a patient is not
achieved because the depth of breathing is not enhanced. Some
common problems associated with these transtracheal catheters are
irritations and traumas of the sensitive inner skin of the windpipe
(tracheal mucosa). It is a common observation that the tip of the
small catheter strikes against the inner wall of trachea as a
consequence of the respiratory movement. In addition to this
mechanical trauma, the surrounding tissue is dried out by the high
flow oxygen stream.
[0008] Furthermore, so-called "Montgomery T-tubes" can be inserted
into the trachea and a patient can obtain oxygen via a shank of the
T-piece external to the patient. In needed, the patient can draw
off secretions using a suction catheter and a vacuum pump. The
patient can breathe freely and speak when the front shank is
closed; however, normal artificial positive pressure ventilation is
not possible via the Montgomery T-tube since the introduced air
escapes upward into the oral cavity or the pharyngeal area. An
additional limitation of the above-referenced therapies is the
impaired mobility of the patient because of inadequate ventilation
or because of the bulk of the apparatuses.
[0009] Jet ventilators are state of the art, but these devices are
not synchronized with a patient's breathing. On the other hand,
invasive ventilators with cuffed tubes are synchronized because
there is a direct feedback of the pressure inside the inflated lung
to the sensors inside the respirator. However, there are no
respiratory systems that use feedback from sensors in the body to
properly synchronize and control the ventilator.
[0010] Whether the breathing disorder is COPD/emphysema, fibrosis,
sleep apnea, or otherwise, difficult breathing is a serious, often
life-threatening problem. Therefore, there is an existing need for
a respiratory system that provides a more efficient method for
supporting the respiration of a patient that can be used to treat
many disorders, are minimally invasive, mobile and taken along by
the patient, and/or reliable in use. Moreover, there is a need for
respiratory support systems that simulate the patient's spontaneous
respiration without adversely affecting the patient's ability to
speak. Additionally, there is a need for a respiratory support
system capable of using pressure or flow signals from inside the
body to properly synchronize and control a ventilator.
SUMMARY OF EXEMPLARY EMBODIMENTS
[0011] The invention includes systems, methods, and apparatuses
that improve the quality of life for patients that require
respiratory support. These respiratory systems, methods, and
apparatuses can provide a more efficient way of supporting the
respiration of a patient by providing additional oxygen when needed
in accordance with the principles of the invention.
[0012] In one embodiment, a tracheal prosthesis and a catheter in
accordance with the principles of the invention can provide for
respiratory support that can be synchronized with the spontaneous
respiration of the patient and still allow the patient to
speak.
[0013] Additional features, advantages, and embodiments of the
invention may be set forth or apparent from consideration of the
following detailed description, drawings, and claims. Moreover, it
is to be understood that both the foregoing summary of the
invention and the following detailed description are exemplary and
intended to provide further explanation without limiting the scope
of the invention as claimed.
BRIEF DESCRIPTION OF THE FIGURES
[0014] The accompanying drawings, which are included to provide a
further understanding of the invention, are incorporated in and
constitute a part of this specification, illustrate preferred
embodiments of the invention and together with the detailed
description serve to explain the principles of the invention.
[0015] In the drawings:
[0016] FIG. 1 shows the upper body of a patient carrying an
embodiment of a system for respiration support in accordance with
the principles of the invention.
[0017] FIG. 2 shows a diagram with a view of the respiration flow
of an emphysema patient without respiration support and with
respiration support in accordance with the principles of the
invention.
[0018] FIG. 3 shows a technically simplified view of an embodiment
of a tracheal prosthesis in accordance with the principles of the
invention.
[0019] FIG. 4 shows another embodiment of a tracheal prosthesis in
accordance with the principles of the invention.
[0020] FIG. 5 shows a schematic of an embodiment of an
oxygen-bearing gas tank and pump showing the conduction of air and
a control unit in accordance with the principles of the
invention.
[0021] FIG. 6 shows an embodiment of the end section of a catheter
in accordance with the principles of the invention.
[0022] FIG. 7 shows the catheter according to FIG. 6 inserted in a
support body in accordance with the principles of the
invention.
[0023] FIGS. 8A and 8B show graphs of breathing data generated from
a bench model test in accordance with the principles of the
invention.
[0024] FIG. 9 shows an embodiment of a catheter and sensors in
accordance with the invention.
[0025] FIG. 10 shows a schematic of an embodiment of a circuit in
accordance with the invention.
[0026] FIG. 11 shows another embodiment of a catheter and sensors
in accordance with the invention.
[0027] FIG. 12 shows a schematic of another circuit in accordance
with the invention.
[0028] FIG. 13 shows a system in accordance with an embodiment of
the invention where the pump and control unit are integrated with
the oxygen tank.
[0029] FIG. 14 shows an embodiment of a distal end of a catheter in
accordance with the invention.
[0030] FIG. 15 shows another embodiment of a distal end of a
catheter in accordance with the invention.
[0031] FIGS. 16 A-16E shows embodiments of a catheter in accordance
with the invention.
[0032] FIG. 17 shows an embodiment of a dual lumen catheter in
accordance with the invention.
[0033] FIG. 18 shows an embodiment of the flow through the catheter
of FIG. 17 during inspiration in accordance with the principles of
the invention.
[0034] FIG. 19 shows an embodiment of the flow through the catheter
of FIG. 17 during expiration in accordance with the principles of
the invention.
[0035] FIG. 20 shows an embodiment of a dual lumen catheter having
a gliding wall in accordance with the invention.
[0036] FIG. 21 shows the catheter of FIG. 20 with the gliding wall
in a different position.
[0037] FIG. 22 shows an expanded view of an air outlet of the
catheter in FIG. 20.
[0038] FIG. 23 shows an expanded view of an air outlet of the
catheter in FIG. 21.
[0039] FIG. 24 is a flow diagram illustrating the operation of an
embodiment of the invention.
[0040] FIG. 25 is a diagram of the overall system.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0041] The present invention, in a preferred embodiment, provides
systems, methods, and apparatus for supporting the respiration of a
patient. This can be accomplished by providing controlled
synchronized ventilation with a directed flow of an oxygen-bearing
gas. The oxygen-bearing gas may be substantially pure oxygen,
mixtures of oxygen and nitrogen, mixtures of oxygen and inert
gases, ambient air, or various combinations thereof. In addition,
the oxygen-bearing gas may include fragrances, aerosolized drugs,
humidification or heating. The oxygen-bearing gas can be provided
as needed upon inhalation and/or expiration, preferably, based upon
sensing of the patient's spontaneous breathing.
[0042] By providing a jet boost of an oxygen-bearing gas upon
inspiration, as needed, the patient can inhale more oxygen.
Preferably, the additional oxygen is administered at the end of
inhalation, in particular, after the peak of inspiratory flow is
detected. The administration of additional oxygen can improve the
depth of ventilation during inhalation. However, the additional
oxygen may be administered at any point during inhalation.
Additionally, a countercurrent or counter pulse during expiration
can be delivered, which creates a back-pressure in the airways
similar to the pursed lips breathing strategy applied by
physiotherapists in order to avoid a collapse of the respiration
paths. By providing an oxygen-bearing gas upon expiration through
counter pulses (e.g. bursts or pulses of oxygen-bearing gas
directed against the direction of the flow during expiration), a
dynamic collapse of the airways can be minimized or prevented, over
inflation of the lung can be minimized, and clearance of carbon
dioxide from the lungs can be improved. Therefore, in accordance
with the principles of the invention, whether used for inhalation
and/or exhalation, breathing requires less energy and the patient's
pain, dyspnea and exhaustion are relieved. Moreover, the systems
and methods of the invention can be used for treatment of many
breathing disorders, including, but not limited to, COPD,
emphysema, fibrosis, and sleep apnea.
[0043] Referring to FIG. 1, in accordance with one embodiment of
the invention, patient P designates a patient suffering from a
breathing disorder, for example, pulmonary emphysema, with
overloading and exhaustion of the respiratory muscles. As a
consequence, the patient cannot inhale enough oxygen because the
lungs are compromised. In addition, the patient cannot exhale
enough carbon dioxide because the patient has slack and collapsing
respiratory paths. The system of FIG. 1 generally includes the
ability to detect the patient's spontaneous respiration and the
ability to provide oxygen to the lungs of the patient during
spontaneous inspiration and/or exhalation.
[0044] As shown, the respiration support of patient P in accordance
with the principles of the invention can be implemented in a
system, method, or apparatus that may be compact and/or portable.
Other systems are contemplated including, for example, providing
for use with a ventilator or oxygen source as shown in FIG. 13. The
overall system of the invention is described in FIG. 25, indicating
the gas source O2, the pump apparatus 1 and control system 12, the
catheter 5 and internal sensors 8, 9 and the patient P. The gas
source O2, pump apparatus 1 and control system 12 can be separate
or integrated components of the system. The control unit 12 may be
connected I to internal sensors 8, 9 and/or external sensors 13,
14.
[0045] In accordance with the embodiment of FIG. 1, in general,
patient P's spontaneous breathing can be detected by way of
sensors. A catheter 5 can be used to introduce oxygen into the
lungs as needed. The sensors and catheter can be associated with
the patient in a variety of ways. As illustrated in FIG. 1, a
catheter 5 is introduced in the trachea. Also, a catheter 5 could
be introduced at other points into a patient P, including, for
example, through the mouth or nose of the patient P, or accessed
into the trachea by an artificially created entry point somewhere
on the body and tunneled internally to and into the trachea. The
catheter 5 can be secured in the trachea in a variety of ways. In
one embodiment, the catheter 5 can be associated with a tracheal
prosthesis as discussed later or using a positioning catheter as
also discussed later with reference to FIGS. 3 and 4, for
example.
[0046] The system of FIG. 1 generally includes an oxygen-bearing
gas source (not shown), gas pump 1, mobile respiratory device 4, a
set of exterior sensors 13, 14, and a set of interior sensors (not
shown) disposed inside the trachea of the patient P. The
oxygen-bearing gas pump 1 can be connected to a gas source (see
FIG. 5) and catheter 5 to introduce an oxygen-bearing gas into the
patient's lungs by way of the trachea, as shown, although other
entry points can be used in accordance with the principles of the
invention as discussed above. According to FIG. 1, the
oxygen-bearing gas pump 1 is shown as a component of a compact,
easily portable respiration device 4. The device 4 could
alternatively be housed in a component with a gas tank or
oxygen-bearing gas source as illustrated in FIG. 13. With the
sensors in accordance with the principles of the invention, the
spontaneous respiration of the patient can be detected. Typically,
the information from the sensors is communicated to the gas pump 1.
However, the information from the sensors may also be communicated
to a cellular telephone or other wireless systems that can
communicate information to a healthcare provider/hospital, etc.,
for 24-hour monitoring and response from the healthcare
provider/hospital, etc. The patient then can receive a pressure
boost of oxygen-bearing gas as needed in accordance with the
principles of the invention. FIG. 2 illustrates both spontaneous
respiration of the patient P without the invention (right) and
respiration supported in accordance with the principles of the
invention (left). The x-axis in this diagram represents time and
the y-axis represents the amount of flow (change in volume over
time) of oxygen-bearing gas, which can be liters per second or any
other appropriate measurements. The spontaneous respiration process
with inspiratory flow and expiratory flow without respiratory
support for patient P is shown in the left half of FIG. 2. The
curve for inhalation is designated by E1 and the curve for
exhalation by A1. As illustrated by curve E1, during inhalation the
tidal volume inhaled is reduced from that of a normal patient. For
example, a patient with emphysema with flattened diaphragms or a
patient with stiff lungs suffering from fibrosis cannot breathe in
enough air (oxygen) in one breath. Both patients typically
experience shallow breathing. Therefore, the patient requires more
breathing cycles to get the requisite amount of oxygen and clear
carbon dioxide. During exhalation, as illustrated by curve A1, the
expiratory flow of the emphysema patient is reduced because the
respiratory paths can be slack and tend to collapse before an
adequate amount of carbon dioxide is expelled from the lungs.
[0047] The sensors allow the patient P's breathing to be monitored
continuously so that a jet flow of oxygen-bearing gas can be
supplied in accordance with the principles of the invention, that
is, when a deeper breath is needed. In particular, at the end of an
inhalation process of the lungs, an additional volume (oxygen) can
be administered to patient P, as discussed in more detail below.
This respiratory flow is illustrated in the right half of FIG. 2.
As illustrated, an additional amount of oxygen-bearing gas provided
to patient P increases the respiratory volume during inhalation
according to curve E2 by the volume difference shown darkened in
the upper curve and designated by E3. The additional amount of
oxygen-bearing gas can have an extra space tidal volume between 25
ml and 150 ml.
[0048] In addition, the exhalation process of the patient can be
braked or slowed by a countercurrent. As a consequence thereof, the
respiratory flow shifts during exhalation along the curve
designated by A2. This purposeful resistance acting opposite to the
exhalation prevents a collapsing of the respiratory paths during
exhalation. In this manner, the exhalation volume can be increased
by the volume also shown darkened and designated by A3. The amount
of carbon dioxide that is exhaled can be increased by a
statistically significant amount. The amount of carbon dioxide that
is exhaled can be increased by at least 5%. Preferably, the amount
of carbon dioxide exhaled is increased from 5% to 30%. More
preferably, the amount of carbon dioxide exhaled is increased about
20% to 30%.
[0049] As a consequence, the invention may avoid insufficient
respiration from an undersupply of oxygen and an increase of carbon
dioxide in the blood. The patient P may be significantly less
stressed and more mobile, and may perceive less or no shortage of
air.
[0050] The sensors for detecting and monitoring respiration will
now be discussed in more detail. To detect spontaneous respiration
of the patient P, sensors can be associated with an end of the
catheter that is disposed in the trachea of the patient P. In one
embodiment, the invention can include connecting the catheter to a
tracheal prosthesis (e.g. FIGS. 3, 4, and 7) or can include a
catheter-positioning device (e.g. FIGS. 14, 15, and 16A-16E) to
more reliably and accurately direct the oxygen flow into the
patient's airways and away from a tracheal wall. Preferably, in
accordance with the principles of the invention, oxygen is
introduced into the patient P in such a manner that the patient P
can freely breathe and speak without restriction.
[0051] In one embodiment, as shown in FIGS. 3 and 4, the sensors
can be disposed on a tracheal prosthesis 2, 3. Each tracheal
prosthesis 2, 3 is shown having a tubular support body 6 with a
connection 7 for a catheter 5. As shown, two sensors 8, 9 detect
spontaneous respiration of the patient P, and can be associated
with a support body 6. The sensors 8, 9 can be thermistors, that
is, temperature dependent resistors. The sensors 8, 9 can detect
tracheal flow of the patient because inspired air and expired air
have different temperatures. The thermistors 8, 9 can be connected
together in a bridge circuit in the apparatus to compensate for
changes in ambient air temperature. Other types of sensors can be
used in accordance with the principles of the invention including,
for example, a pressure sensor as discussed later. Both sensors 8,
9 can be located on an inner wall 10 of the support body 6 (FIG.
3), or one sensor 8 can be fixed on the inner wall 10 of the
support body 6 and the other sensor 9 can be located on an outer
wall 11 of the support body 6 (FIG. 4). The sensors 8, 9
communicate with a control unit 12 for activating an oxygen jet
pump 1. The sensors 8, 9 can be connected by wires or by wireless
communication. The control unit 12 can be any type of
microprocessor that is capable of processing the collected data in
accordance with the invention. The control unit 12 is schematically
shown in FIG. 5 with its inputs (I) and outputs (O). The inputs (I)
represent information coming from the sensors. The outputs (O)
represent information that is used to control the pump 1.
[0052] In the tracheal prosthesis 2 according to FIG. 3, the jet
catheter 5 can be inserted via connection 7 into the support body
6. An end 15 of jet catheter 5, located in support body 6, is
preferably guided or deflected approximately parallel to its
longitudinal axis L. The data lines from sensors 8, 9 to the
control unit 12 run inside the catheter 5. The invention is not
limited to data lines; transmission from sensors can be any type of
transmission, including wireless. On the discharge side, the end 15
of the jet catheter 5 is preferably designed as a jet nozzle 25.
The jet nozzle 25 increases the speed of an oxygen current being
discharged from the catheter 5, and the current is conducted in the
direction of the bronchial tract. The diameter of the support body
6 is dimensioned with a sufficiently free lumen in such a manner
that the patient P can freely breathe and speak even with the
integrated catheter 5.
[0053] In another embodiment, a separate coupling 18 is provided on
the connection 7 in the tracheal prosthesis 3 according to FIG. 4.
The catheter 5 can be connected to the tracheal prosthesis 3 with
the separate coupling 18. In this instance, a fixed longitudinal
section 19 aligned parallel to the longitudinal axis L can serve as
the catheter end in the support body 6, and the oxygen current is
conducted via a jet nozzle 26 in the direction of the bronchial
tract.
[0054] The tracheal prosthesis, when used, can comprise various
configurations, shapes and dimensions. For example, the tube could
be T-shaped or L-shaped or otherwise. The size, shape, and/or
cross-section can vary, for example, to accommodate removal or to
direct the catheter. The tracheal prosthesis could be a portion of
a tube having, for example, a semi circular cross-section.
Furthermore, expandable and self-expandable prongs or petals can be
used at the tracheal opening to secure the prosthesis in place. In
one embodiment, the prosthesis can include a tubular member with a
tracheal side opening including prongs or petals surrounding, in
whole or in part, the access hole. The prongs or petals may
function like a rivet in the neck opening. The tracheal prosthesis
can also be coated to avoid mucus retention, prevent the formation
of granulation tissue, or can act as a drug-releasing device. The
tracheal prosthesis may also include other coatings, such as
lubricious coatings and hydrogel anesthetics. Thus, the tracheal
prosthesis can serve as a guide for the catheter, to hold sensing
devices, serve as a drug delivery device, and/or to minimize mucus
plugs that can form on the catheter tip.
[0055] In addition to internal sensors, external sensors can be
provided. FIG. 1 also shows respiration sensors 13, 14, preferably,
impedance electrodes or respibands. Signals from the sensors 13, 14
are also for detecting the spontaneous respiratory efforts of the
patient P. An exact image of the respiration process of patient P
can be obtained by processing the measured values received via
sensors 8, 9 and 13, 14. In addition, the safety against false
measurements or the failure of one of sensors 8, 9 and/or 13, 14
can be increased due to redundancy. Although the sensors are shown
in certain locations on the patient P, other locations that would
allow the sensor to sense the patient's respiration, directly or
indirectly, can be used. For example, sensors can be provided on
the catheter as discussed later. Alternatively, a pill-type sensor
or nano device can be used and/or implanted to communicate by, for
example, wireless transmission to communicate with the control unit
to operate the oxygen flow through the catheter in accordance with
the principles of the invention.
[0056] One embodiment where sensors are provided on the catheter is
shown in FIG. 6. FIG. 6 shows a catheter 28 with a long, flexible
tube 29 and an end 31 on the discharge side bent in a curvature 30.
The catheter 28 can be preformed to provide a desired curvature 30.
With the appropriate curvature 30, the catheter 28 can be entered
into the trachea with or without use of a prosthesis. In this
embodiment, two sensors 32, 33 for detecting the spontaneous
respiration of the patient P can be fastened on the end of the
catheter 28. The sensors 32, 33 are preferably thermistors, but as
in all embodiments herein, could be other types of sensors.
Furthermore, in other embodiments of the invention, additional
sensors may be used. In still other embodiments of the invention,
fewer sensors may be used. Data lines are not shown in the drawing
for the sake of simplicity and could include any form of data
transmission. In a hard-wired embodiment, data lines can run
through the catheter 28. A catheter flange 34 designates a stop for
use with a support body 36, as shown in FIG. 7. It can also be seen
that an end 31 of the catheter 28 is provided with a jet nozzle 35.
The cross-section of gas flow is reduced relative to the
cross-section of the catheter 28 in the jet nozzle 35 so that the
discharge rate of the supplied oxygen is increased.
[0057] The catheter 28 can be introduced into the support body 36,
as shown in FIG. 7. The support body 36 is located in the trachea
of the patient P. A connection to the outside is established via a
connection 37. In the body, the tip or jet nozzle end 35 of the
catheter 28 can be disposed in the trachea. Preferably, the tip of
the catheter 28 does not touch the tracheal wall. The support body
36 can be a traditional Montgomery T-stent.
[0058] FIGS. 8A and 8B show measurements in a lung model emulating
respiratory diseases. FIGS. 8A and 8B graphically illustrate an
increased tidal volume with the invention. FIG. 8A shows a bar
graph of the volume (ml) of breath comparing a pathologically low
breath of a patient with emphysema at about 90 ml; the volume with
jet oxygen in accordance with the principles of the invention upon
inhalation at about 260 ml; and the volume with the jet oxygen in
accordance with the principles of the invention upon inhalation and
with the flow brake (oxygen jet) upon exhalation at about 300 ml.
FIG. 8B shows a graph of the flow of breath (liters per second)
over time for a breath of an emphysema patient; the flow with jet
oxygen in accordance with the principles of the invention upon
inhalation; and the flow with jet oxygen in accordance with the
principles of the invention upon inhalation and with the flow brake
(oxygen jet) upon exhalation.
[0059] In another embodiment shown in FIGS. 9 and 10, thermistors
81 and 82 can be provided on a catheter tip inside the trachea. The
thermistor 81 is more exposed to the gas stream than thermistor 82,
which is protected against fast temperature changes because it is
inside the catheter wall (or under a protection film).
Alternatively, multiple thermistors with different response times
could be used. Over a longer period (e.g. 10 seconds), both mean
temperatures will be the same (equilibrium) and the bridge (FIG.
10) will be readjusted. This compensates for changes in ambient
temperature, fever, etc. Rapid changes based upon breathing in
colder air and breathing out warmer air is detected by the
thermistor 81. The output signal is sent through a differentiator.
The peaks of the thermistor signal match the highest flow rates.
The minimum in the differentiated signal matches the peak of the
inspiratory flow and the peak of the expiratory flow.
Undifferentiated and differentiated signals are fed into the
microprocessor. One way to determine peak inspiratory flow (trigger
for beginning introduction of oxygen) would be to look for minimum
in absolute temperature (cold air comes in) and zero change of
temperature (differentiated signal is zero). The advantage of using
the above multiple thermistor approach is that the difference
between the signals from the two thermistors cancels out flow
artifacts found in the measured respiratory flow pattern, such as
would be caused by vibration or other anticipated events, and to
compensate for drift in the thermistor signal such as would be
caused by changing external or internal temperature or humidity
conditions.
[0060] In another embodiment, as shown in FIGS. 11 and 12, FIG. 11
shows a pressure transducer that is a modified silicone wire strain
gauge element 90. Instead of a typical silicone membrane, the wall
of the catheter is used. If the wall of the catheter deforms under
the pressure swings inside the trachea (breathing effort), then an
electrical signal from the bridge amplifier is fed into a
microprocessor. This embodiment can be used alternatively to the
thermistors, as a redundant signal or as a back-up signal. Other
sensors could be semiconductor flow sensors or pressure sensors.
FIG. 12 shows a circuit diagram of a bridge amplifier.
[0061] Other sensors can be used in accordance with the invention.
For example, sensors and/or secondary control sensors could be:
respibands (chest wall strain gages), respitrace signals
(conductance plethysmographs), pressure sensors inside or outside
the body, transthoracic electrical impedance measuring devices,
flow sensors at the mouth or nose (pneumotachographs), and/or
capnometers (carbon-dioxide sensors). Moreover, the sensors in
accordance with the invention can communicate data or information
to the control unit by any devices, mechanisms, or methods. For
example, communication can occur by way of wire, wireless, or
remote transmission. The advantage of using non-thermistor sensors
is that the thermistor approach may have the disadvantage of the
thermistor head collecting airway mucus, which could be corrected
for in a variety of ways such as with cleaning. However, other
non-thermistor sensors may be less susceptible to annoyances like
mucus collection. Further, with thermistor sensors, inevitable
changes in ambient temperature, while compensatable in the
thermistor signal processing algorithms, are potentially
problematic to system reliability. Therefore, the other types of
sensors stated above may be advantageous over thermistor sensors,
or in addition to the thermistor sensors.
[0062] In addition to measuring the respiration pattern, it is
often desirable to measure airway pressure for safety reasons, for
which thermistor sensors may not be the best approach. Therefore,
some of the sensors mentioned above can also be used as a safety
control device. For example, pressure sensors can be used to sense
the inspiration of the patient (like the thermistors), but they can
also be used to sense a high pressure in the trachea and shut off
the jet machine in order to prevent baro-trauma (damage from high
pressure).
[0063] An oxygen-bearing gas is provided on demand by the gas pump
1. The gas pump 1 is schematically shown in FIG. 5. The gas pump 1
can be a piston pump with a double-acting piston 20 arranged in a
cylinder 27. The piston pump of the present embodiment comprises
four valves V1 to V4. Other piston pumps (not shown) may have
greater than or fewer than four valves. The supply of oxygen
emanates from an external oxygen reservoir via a connection 21. The
switching states of valves V1 to V4 and the supply lines and
removal lines are designated by letters a to g. Other types of
pumps can be used in accordance with the principles of the
invention.
[0064] The gas pump 1 functions in the apparatus during the support
of respiration as follows. When valve V1 is open from c to a (b to
c closed) and valve V2 is open from b to e (e to d closed), piston
20 moves to the left in the plane of the figure and the oxygen
flows via outlet 22 and jet catheter 5 to the patient P. An
additional amount of oxygen E3 is administered during the
inhalation process of the patient P.
[0065] When valve V1 is open from b to c (c to a closed) and valve
V2 is open from e to d (b to e closed), piston 20 moves to the
right in the plane of the figure and the flow of oxygen takes place
in the direction of valve V3. Valve V3 is connected to the ambient
air via an outlet 23. In the instance in which valve V3 is open
from d to g, the oxygen flows off without expiration brake. That
means that the exhalation process is not braked by a
countercurrent.
[0066] If valve V3 is closed from d to g and open from d to f, the
oxygen flows via access path 24 in the direction of the outlet 22
and the catheter 5 in order to be administered to the patient P
during the exhalation process and in order to break the respiratory
flow. The countercurrent prevents a collapsing of the respiratory
paths and keeps them open, making a deeper exhalation possible.
[0067] Furthermore, valve V4 is located in access path 24 of the
apparatus, via which the flow through (f to a) can be variably
adjusted. This advantageously can be a proportional valve with
pulse-width modulation.
[0068] As discussed above, the catheter preferably includes a jet
nozzle. Any type of jet nozzle can be used to achieve the necessary
jet flow. The jet flow speed in accordance with the invention can
be significantly higher than 100 m/s. By comparison, the speed
through a conventional ventilator tube or mask is significantly
lower than 100 m/s. When the jet flow rate is high enough, there is
enough speed so that directed flow is accomplished and no sealing
tube cuff would be necessary. Under normal ventilation, the
volumetric inspiratory flow rate is in the range of about 500
m.sup.3 to 1000 cm.sup.3 in 2 seconds. A peak inspiratory flow
maximum can be 1000 cm.sup.3/second. In the case of normal invasive
ventilation, the flow of 1000 cm.sup.3/s (peak) goes through a tube
of approximately 8 mm diameter. The speed of this gas stream,
determined by dividing the volumetric inspiratory flow rate by the
area of the tube, is 1000 cm.sup.3/(0.4).sup.2 cm.sup.2*Pi=2000
cm/s=20 m/s. During jet ventilation, approximately half of this
flow goes through a jet cannula of 1.5 mm diameter. As the flow
profile is rectangular, the peak flow rate is 500 cm.sup.3/s.
Therefore, the speed of the jet gas stream is 500
cm.sup.3/(0.075).sup.2 cm.sup.2*Pi=28313 cm/s=283 m/s. In
accordance with a preferred embodiment of the invention, 100 ml
(cm.sup.3) are pressed through a catheter of approx 1.5 mm diameter
in half a second. Preferably, the peak flow for this embodiment is
100 cm.sup.3 in 0.25 seconds=400 cm.sup.3/s. The speed of this gas
stream is 400 cm.sup.3/(0.075).sup.2 cm.sup.2*Pi=22650 cm/s=226
m/s. In other preferred embodiments, the speed of the gas stream is
from approximately 100 m/s to approximately 300 m/s. Preferably,
the speed of the gas stream is from approximately 200 m/s to
approximately 300 m/s. Preferably, the speed of the gas stream is
from approximately 250 m/s to approximately 300 m/s.
[0069] When the tip of the catheter touches the wall of the
trachea, there is a potential risk of tissue damage. The catheter
tip or the high flow gas stream can harm the mucosa. To efficiently
and effectively direct the air inside the body, the catheter can be
configured to provide a directed flow of oxygen. In particular, the
catheter is preferably configured so that the exit of air from the
catheter output end can expel and direct air down the center of the
trachea to avoid directing the jet flow of oxygen against the
tracheal wall. Also, the catheter tips are preferably configured to
minimize venturi and the mucus formation proximal to the venturi on
the outer wall of the catheter. A shielding Montgomery T-tube as
described above can be used to overcome that problem. In FIGS. 14
and 15, the catheters are configured such that the catheter tip or
jet nozzle avoids contact with the wall of the airway, the tip is
substantially centered in the trachea. This can be accomplished by
configuring the catheter so that the catheter will contact the
tracheal wall at several locations to distribute the local
pressure, and the tip where the jet flow of oxygen exits the
catheter is substantially centered in the trachea. Accordingly, the
use of a tracheal prosthesis is not necessary. One way to avoid the
contact between the tip Get nozzle) and the airway wall is to bend
the catheter like a zigzag in two planes as illustrated in FIG. 14.
Another embodiment is a corkscrew as illustrated in FIG. 15.
[0070] FIGS. 16A-16E show alternate embodiments for centering the
catheter where balloons (FIGS. 16A and 16B) or clips (FIGS.
16C-16E) can be used to center the catheter tip. FIG. 16A shows a
balloon for centering the catheter tip where the balloon has a
roughly circular cross section through line J-J. Openings in the
balloon may be located in the longitudinal direction of the
catheter. FIG. 16B shows a balloon for centering the catheter tip
where the balloon can have multiple extensions. The extensions may
appear as cone-shaped projections in cross section K-K along the
longitudinal direction of the catheter. FIG. 16C shows clips
extending radially out from the catheter. The clips in this
embodiment are relatively flat and extend outward in opposing
pairs. FIG. 16D shows another embodiment of clips with extensions
on the end of the clips. The clips and extensions may extend at
multiple angles relative to the catheter for centering the catheter
tip within the trachea. FIG. 16E shows another embodiment of clips
having shaped protrusions at various locations along the length of
the catheter. The protrusions may have flat tops with rounded edges
and undercuts. Preferably, the clips of the various embodiments are
made of a resilient material.
[0071] Referring now to FIGS. 17-23, a dual lumen catheter will be
described. The invention can also include the ability to better
distribute the directed flow (FIGS. 17-19) and/or change the
direction of the flow (FIGS. 20-23). FIGS. 17-19 show a dual lumen
catheter 172. The catheter tip, shown generally at 170, is disposed
in a trachea 174. The catheter 172 has two lumens, formed by inner
cannula 176 and outer cannula 178. Inner cannula 176 directs flow
to a catheter nozzle 180, as discussed above. As shown in FIG. 18,
upon inspiration, inspired flow is enhanced by air entrainment from
the jet flow through the inner cannula plus by the additional jet
flow itself 176. Upon expiration (FIG. 19), exhaled flow is
enhanced by turbulence from counter flow through ports 182 by means
of propping the respiratory paths open. The ports 182 need not be
of any particular shape and may be, for example, circular,
hexagonal, oval, or slits. Although not shown, turbulent flow could
also be provided through inner cannula 176 during exhalation to
enhance exhaled flow depending upon the desired effect.
[0072] Referring to FIGS. 20-23, another embodiment of a catheter
is shown. A catheter 200 is shown with a distal tip 202 in a
trachea 204. The catheter tip 202 includes a cannula configuration
with an inner lumen 206, an outer lumen 208 concentric to the inner
lumen, and a gliding sheath 210. In this embodiment, the gliding
sheath 210 moves relative to the cannula to allow ports 210 to
change the direction of oxygen flow as illustrated in FIG. 20
verses FIG. 21, and in close-up in FIG. 22 verses FIG. 23. As shown
in FIG. 22, upon expiration, the flow braking turbulence caused by
movement of the gliding sheath 210 may create a resistance such as
in pursed-lip breathing, which can prop the respiratory paths open
to enhance the amount of exhaled volume. Or, as shown in FIG. 23,
the addition of venturi flow towards the mouth caused by movement
of the gliding sheath 210 can entrain exhaled flow to enhance the
overall exhaled volume. Although the gliding sheath 210 is shown to
move, more or other parts can be made to move to accomplish the
directed flow of this embodiment. For example, flow braking
turbulence or venturi flow toward the mouth may be produced by the
use of shutters, louvers, or slats.
[0073] Regardless, the flow can be directed towards the mouth or
back into the lungs as desired. The flow brake for the expiratory
flow of the patient can be adjusted from disturbance (pursed lips
effect) or to augmentation (venturi principle). The whole catheter
preferably does not have more than 4 mm outer diameter, but can be
very versatile. This embodiment, like the other embodiments of the
invention, can also be used to apply vibratory flow to the
respiratory paths to improve mucus clearance.
[0074] The system in accordance with the principles of the
invention can be implantable. In one embodiment, the system
including the jet catheter and system sensors can be implanted
inside the body. Although it is possible to implant the pump, it is
contemplated that tubing attached to the pump can be connected to a
connector exposed from the body. The pump tubing can be attached to
the connector in a conventional manner so that the oxygen-bearing
gas flows through the implanted jet catheters into the patient in
accordance with the principles of the invention. The system can be
tailored to the needs of the patient. The jet pressure and timing
and duration of the pulses can be monitored and controlled and
adjusted as necessary based on the patient's respiratory condition
and general status. As shown in FIG. 1, the catheter can extend
along the outside of the body. Alternatively, the catheter could be
implanted inside the patient's body. For example, the catheter
could have one exposed end for connection with the pump and some or
all of the remainder of the catheter could be implanted inside the
patient and/or under the skin of the patient. The output end of the
catheter could, for example, be exposed for connection to the
tracheal prosthesis or positioned in the nose or mouth.
Furthermore, the portion of the catheter disposed in the patient
can be treated. For example, it can be treated with an
antibacterial, a drug, a lubricious coating, a treatment to prevent
mucous formation, or otherwise.
[0075] FIG. 24 is a flow diagram illustrating an embodiment of a
method of the invention. In accordance with this embodiment of the
invention, the patient is provided with the system in accordance
with the invention. The system is used to detect the spontaneous
respiration of the patient. At or near the peak of inspiration
flow, the system determines whether additional oxygen is needed by
the patient. If yes, the system provides a jet boost of oxygen to
the patient. Then at or near the peak of expiration flow, the
system determines whether more carbon dioxide must be exhaled by
the patient. If more must be exhaled, then the system provides a
counter current of oxygen to the patient. The process is repeated
as needed. The advantage of this embodiment is to allow the therapy
to match the needs of the patient. Other ventilator systems tend to
apply a predetermined therapy regardless of the changing condition
of the patient, until a clinician changes a setting on the
ventilator. Other ventilator systems are therapeutically suboptimal
for a wide range of patient situations, often leading to over
treatment, making the patient too dependent on artificial
ventilation, or leading to under treatment, and thus worsening the
patient's clinical condition. Therefore, in accordance with this
invention the ventilator will adjust an output to the patient based
on the patient's need. The ventilator can make a determination by
using patient information already obtained by the sensors, such as
breath rate, depth of respiration, length of inspiration or
exhalation, agitation, or gas concentration levels. For example, if
a patient is exercising and an unusually low exhalation flow rate
is detected by the sensors, indicating that airways are collapsing
too much during exhalation, then, exhalation counter flow could be
switched on or increased to prop the airways open and enhance
exhaled flow. Or, for example, if the patient's breathing becomes
unusually fast as measured by the breath sensors, indicating the
patient is compensating for shortness of breath, the inspiratory
augmentation pulse could be switched on or increased to relieve the
patient's dyspnea. Or as another example, gas composition sensors
detecting CO.sub.2 and O.sub.2 levels in the airway can determine
if the therapy is adequate and increase or lower the therapy as
needed.
[0076] As mentioned above, the principles of the invention can be
used in treating and/or assisting in the treatment of a variety of
breathing disorders and/or breathing difficulties. In such
treatments, the invention can provide an oxygen-bearing gas into
any of the airways of the patient. In one such embodiment, instead
of directing the oxygen-bearing gas into the lungs, the
oxygen-bearing gas can be directed into the upper airways,
including, for example, using a catheter and, more particularly, a
tracheal or coated catheter.
[0077] In one embodiment, an oxygen-bearing gas can be directed
into the upper airways to treat or assist in the treatment of sleep
apnea. Sleep apnea is a serious sleep disorder that occurs when a
person's breathing is interrupted repeatedly during their sleep.
People with untreated sleep apnea stop breathing repeatedly during
their sleep, sometimes hundreds of times during the night. One type
of sleep apnea can be referred to as obstructive sleep apnea (OSA).
OSA is caused by a blockage of the airway, usually when the soft
tissue in the rear of the throat collapses during sleep. Currently,
sleep apnea can be treated by continuous positive airway pressure
(CPAP) treatment in which a patient wears a mask over the nose
and/or mouth. An air blower forces air through the upper airway.
The air pressure is adjusted so that it is just enough to prevent
the upper airway tissue from collapsing during sleep. The pressure
is constant and continuous, and the flow rate is sometimes adjusted
by bilevel positive airways pressure (BiPAP) machines, depending on
need. CPAP can prevent airway closure while in use, but apnea
episodes return when CPAP is stopped or it is used improperly. The
use of the nasal mask and oral delivery of gas/oxygen/ambient air
is cumbersome and inhibits the patient. In contrast, in accordance
with the principles of the invention, the oxygen-bearing gas can be
provided to the patient by way of a catheter, including a tracheal
catheter. The oxygen-bearing gas can be provided to the patient
based upon the breathing monitored by sensors in accordance with
the invention. This includes sensors placed in the upper airway
tissues that sense tissue movement or collapse. These sensors could
communicate to the pump via wireless or hard wire. The sensors can
detect the breathing cycles and based upon that information the
oxygen flow and volume can be controlled. The oxygen-bearing gas
can be provided continuously, intermittently, or pulsed as needed.
Alternatively, as discussed above, the oxygen-bearing gas can be
provided in a jet flow. Further, the portable respiration device
can be programmed such that a continuous flow of oxygen-bearing gas
is delivered and a jet boost is activated only if necessary. As a
result, the oxygen can be tailored to the patient's needs.
[0078] The invention can be used to treat any kind of disease where
alveolar ventilation and oxygen uptake are impaired. This includes
chronic obstructive airway pulmonary diseases including lung
emphysema, as well as restrictive diseases such as pulmonary
fibrosis, sarcoidosis, pleural adhesions, chest-wall diseases,
neuromuscular diseases, and phrenic nerve paralysis. Basically,
whenever a patient has a problem breathing deeply enough, the
invention can be helpful.
[0079] In contrast to the present invention, typical invasive
ventilation is provided all the time, but a patient cannot exercise
at all (walk carry something, etc.). The patient has a tube in the
throat and is fixed to a bed (usually in intensive care).
Non-invasive ventilation with a mask is sometimes provided in order
to help the patient's weak breathing muscles recover. For example,
if the patient is ventilated overnight, the diaphragm and auxiliary
muscles can rest, and the patient can perform better at daytime.
However, whenever the patient would need help most (during
exercise), the patient has to breathe on their own. With the
minimally invasive or percutaneous ventilation and the synchronized
jet from the system in accordance with the invention, support is
given when needed (e.g., during exercise).
[0080] Although the foregoing description is directed to the
preferred embodiments of the invention, it is noted that other
variations and modifications will be apparent to those skilled in
the art, and may be made departing from the spirit or scope of the
invention. Moreover, features described in connection with one
embodiment of the invention may be used in conjunction with other
embodiments, even if not explicitly stated above. The present
invention may be embodied in other specific forms without departing
from its spirit or essential characteristics. The described
embodiments are to be considered in all respects only as
illustrative and not restrictive. The scope of the invention is,
therefore, indicated by the appended claims, rather than by the
foregoing description. All changes, which come within the meaning
and range of equivalency of the claims, are to be embraced within
their scope.
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