U.S. patent application number 12/754437 was filed with the patent office on 2010-10-07 for method and arrangement for respiratory support for a patient airway prosthesis and catheter.
This patent application is currently assigned to Breathe Technologies, Inc.. Invention is credited to Lutz Freitag.
Application Number | 20100252043 12/754437 |
Document ID | / |
Family ID | 34129567 |
Filed Date | 2010-10-07 |
United States Patent
Application |
20100252043 |
Kind Code |
A1 |
Freitag; Lutz |
October 7, 2010 |
METHOD AND ARRANGEMENT FOR RESPIRATORY SUPPORT FOR A PATIENT AIRWAY
PROSTHESIS AND CATHETER
Abstract
The invention relates to a method and an arrangement for
respiratory support for a patient and an airway prosthesis. The
spontaneous breathing of a patient is recorded with sensors and an
additional amount of oxygen administered by means of a jet gas flow
at the end of a lung inhalation process. Oxygen uptake on
inhalation is thus improved. Where necessary the exhalation process
of the patient can be retarded by a counter-current to prevent a
collapse of the airways. The above manner of proceeding is achieved
by means of an arrangement, comprising an oxygen pump connected to
an oxygen source and an airway prosthesis, which may be connected
by means of a catheter. The spontaneous breathing of the patient is
recorded by means of sensors, connected to a controller, for
activating the oxygen pump. The airway prosthesis has a tubular
nozzle body with a connector for the catheter, whereby two of the
sensors are provided on the nozzle body. The airway prosthesis and
the integrated or introduced jet catheter are of such a size that
the patient may breathe and speak freely.
Inventors: |
Freitag; Lutz; (Hemer,
DE) |
Correspondence
Address: |
PATTON BOGGS LLP
8484 WESTPARK DRIVE, SUITE 900
MCLEAN
VA
22102
US
|
Assignee: |
Breathe Technologies, Inc.
San Ramon
CA
|
Family ID: |
34129567 |
Appl. No.: |
12/754437 |
Filed: |
April 5, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10567746 |
Sep 10, 2007 |
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PCT/DE04/01646 |
Jul 23, 2004 |
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12754437 |
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Current U.S.
Class: |
128/204.23 |
Current CPC
Class: |
A61M 16/12 20130101;
A61M 2025/0002 20130101; A61M 16/0677 20140204; A61M 2202/0208
20130101; A61M 16/0072 20130101; A61M 2205/106 20130101; A61M
2016/0036 20130101; A61M 16/127 20140204; A61M 2016/0021 20130101;
A61M 16/0465 20130101 |
Class at
Publication: |
128/204.23 |
International
Class: |
A61M 16/00 20060101
A61M016/00 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 11, 2003 |
DE |
103 37 138.9 |
Claims
1. A process for respiratory support for a patient, wherein the
patient's spontaneous respiration is recorded by sensors, and an
additional quantity of oxygen is administered to the lung at the
end of an inhalation process.
2. The process according to claim 1, wherein the oxygen quantity
has a volume of 25 ml to 150 ml.
3. The process according claim 1, wherein the patient's exhalation
process is slowed by a counter-flow.
4. An arrangement for respiratory support to a patient, including
an oxygen pump to be connected to an oxygen supply, as well as an
airway prosthesis, to be connected via a catheter, wherein sensors
are intended to record the patient's spontaneous respiration, same
sensors being connected with a control unit to activate the oxygen
pump, and the airway prosthesis possesses a tubular support body
with a connector for the catheter, wherein two of the sensors are
assigned to the support body.
5. The arrangement according to claim 4, in which a sensor is
placed against the interior wall of the support body.
6. The arrangement according to claim 4, wherein the end of the
catheter which is located within the support body is redirected so
as to be approximately parallel to its longitudinal axis, as well
as being provided with a jet nozzle at its end.
7. The arrangement according to claim 4 in which the oxygen pump
consists of a piston pump.
8. The arrangement according to claim in which the catheter is
provided with a double lumen.
9. The arrangement according to claim 4, wherein further
respiratory sensors are intended in addition to the sensors.
10. An airway prosthesis possessing a tubular support body with a
connector for a jet catheter, wherein the support body includes at
least two sensors.
11. The airway prosthesis according to claim 10, wherein a sensor
is affixed to the internal wall of the support body.
12. The airway prosthesis according to claim 10, wherein the
catheter end within the support body is directed so as to be
parallel to its longitudinal axis.
13. A catheter as a tubular instrument to one of whose ends at
least one sensor is affixed.
14. The catheter according to claim 13 in which the end possesses a
jet nozzle.
15. The catheter according to claim 13, wherein the end is bent.
Description
[0001] The invention concerns a method and an arrangement for
respiratory support of the patient, as well as an airway prosthesis
and a catheter for use herein.
[0002] To allow the body to take up oxygen and release carbon
dioxide, both components of the respiratory bronchial system must
function. The lung as a gas exchanging organ and the respiratory
pump as a ventilation organ which transports air into the lung and
back out again. The correct function of the respiratory pump
requires the respiration centre in the brain, central and
peripheral nerves, the bony thorax and the respiratory musculature,
as well as clear, stable airways.
[0003] In certain illnesses, there is a long-term overuse or
exhaustion of the respiratory pump. A typical illness is lung
emphysema with flat diaphragm, and inability to contract. In lung
emphysema, the airways are usually extremely limp and collapsed.
Due to the flattened, overstretched diaphragm, the patient cannot
inhale deeply enough. Due to the collapsed airways, the patient is
also unable to exhale sufficiently. This leads to insufficient
respiration with oxygen undersupply and increased carbon dioxide
levels in the bloodstream, which is also known as ventilatory
insufficiency.
[0004] Treatment of inhalatory weakness is often done with a
respirator. The so-called home respiration is artificial
respiration to support or completely unburden the respiratory
pump.
[0005] Respiration can take place non-invasively via a tube and a
nose or mouth mask which the patient can put on and take off by
himself as required. However, this restricts free breathing and the
patient's ability to speak. Furthermore, a blocked tracheal cannula
can be inserted into the trachea. This also means that the patient
can no longer speak.
[0006] In invasive respiration, this is usually carried out via a
tracheostoma. This is a surgically created opening in the trachea.
Via the opening, a finger-thick catheter with a blocking balloon is
inserted into the trachea and connected to a respirator. This
enables sufficiently deep respiration, but hinders the patient in
speaking. Aside from respiration, there is transtracheal oxygen
administration via thinner catheters. Corresponding suggestions can
be found in U.S. Pat. No. 5,181,509 or U.S. Pat. No. 5,279,288. In
this manner, the patient receives high-dosed oxygen in a continuous
stream with a fixedly adjusted frequency. The oxygen is regulated
manually via a regulator. It is not possible to adapt to the
patient's natural respiration process. Respiration is not deepened.
The catheter end which is introduced into the airway may also lead
to irritation and local trauma to the surrounding tissues by
striking the trachea due to the movement of respiration, or the
surrounding tissues are dried out by the jet stream.
[0007] So-called "Montgomery-T tubes" which are placed within the
trachea are also known. Through these, the patient can receive
oxygen via the segment of the T which is directed to the outside.
Furthermore, the patient can suction off his secretions himself
when required. The patient can breathe freely and speak if the
front segment is closed. However, artificial respiration is not
possible through the "Montgomery-T tube", since the air which is
introduced escapes upwards into the mouth and/or pharynx.
[0008] Based on the state of the art, the invention therefore has
the task of providing a more efficient process for respiratory
support for a patient, and to create an arrangement for this
purpose which can also be carried by the patient and is safe to
use. Furthermore, the invention aims at an airway prosthesis and a
catheter which enables respiratory support that is synchronized
with the patient's spontaneous respiration without negatively
affecting the ability to speak.
[0009] The solution of the method section of the task consists of a
method which includes the measures in Patent claim 1.
[0010] According to this, the patient's spontaneous respiration is
recorded by sensors, and an additional amount of oxygen is
administered at the end of a respiratory process. This can take
place in the form of an oxygen burst via a jet catheter from an
oxygen reservoir. Herein, there is synchronization of respiratory
support with the patient's natural respiration. Respiratory depth
which is reduced due to overwork or exhaustion of the respiratory
pump is thus compensated. Due to the additional oxygen quantity,
respiration is kept at sufficient levels. Oxygen undersupply and
increased carbon dioxide in the blood are thereby avoided.
[0011] For practical purposes, the additional oxygen quantities
have a volume between 25 ml and 150 ml, as shown in Patent claim
2.
[0012] If desired, the patient's exhalation process can also be
slowed by a counter-flow as needed. This is always recommended when
the patient's airways are collapsible, that is, they collapse
during respiration, which can extremely hinder the exhalation
process. This is prevented by the measure of patent claim 3 in that
a counter-flow is applied during exhalation, keeping the airways
open and preventing their collapse.
[0013] A representational solution to the problem on which the
invention is founded is an arrangement in accordance with the
characteristics of patent claim 4. This intends an oxygen pump
which can be connected to an oxygen source, as well as an airway
prosthesis which, if applicable, can be connected via a catheter
with the further use of a supply tube. The outflow end of the
catheter forces the oxygen flow into a jet character. This may, for
instance, be accomplished by a reduction of the cross-section. In
principle, the end of the catheter may also be equipped with a jet
nozzle. Furthermore, the invention intends sensors to record the
patient's spontaneous respiration. These sensors are linked with a
control unit for activation of the oxygen pump. The airway
prosthesis possesses a tubular support body with a connector for
the catheter. The support body and the integrated catheter are
dimensioned so that the patient can breathe and speak freely,
without restriction. The main respiration takes place through the
larger inner lumen of the airway prosthesis. Spontaneous
respiration, coughing and speaking are not hindered. Furthermore,
the support body includes at least two sensors which are part of
the arrangement.
[0014] The airway prosthesis is implanted in the airway of the
patient. A small airway incision is made to provide access for the
catheter to the outside. The catheter can be led directly into the
support body with one end via the connector. It is also possible to
connect the catheter to the connector externally via a coupling
mechanism.
[0015] The sensors serve to record the patient's spontaneous
respiration. Various respiration sensors, such as respiration flow
sensors or pressure sensors, can be used. Thermistors are
particularly advantageous. These are semi-conductor components with
temperature-dependent resistance. The temperature dependency of the
resistance forces is used to record the inhalation and exhalation
processes, since the exhaled air in the lung is naturally warmer
within the airway than the inhaled air.
[0016] In accordance with the characteristics of patent claim 5, a
sensor is applied to the internal wall of the supporting body. The
other sensor is arranged on the external wall of the support body
or embedded within the support body itself.
[0017] A bridge circuit is provided for compensation of the
recorded measurement value differences between the internal and
external sensors. This double arrangement can be used to equalize
environmental influences, such as temperature variations etc.
[0018] In accordance with the characteristics of patent claim 6,
the catheter end which is located within the support body is
largely positioned parallel to its longitudinal axis and provided
with a jet nozzle at its end. This may be a separate nozzle.
However, the jet nozzle may also be designed in the form of a
reduction in cross-section at the end of the catheter. In this
manner, the air or oxygen flow which is introduced via the catheter
can be aimed in the direction of the lungs, and this can be
accomplished with a laminar flow. The oxygen is prevented from
escaping into the mouth or pharyngeal space. The support body which
receives the catheter end or end piece prevents dehydration of the
surrounding tissues. Trauma to the airway and/or surrounding
tissues, e.g. through movements of the catheter end, is furthermore
avoided.
[0019] The oxygen pump is functionally structured as a piston pump.
The use of a cylinder with a double-action piston or a movable
membrane is particularly preferable. Such an oxygen pump excels due
to its compact construction. Furthermore, reliable adjustment of
the supplied oxygen quantity is possible in supporting both the
exhalation process and the inhalation process. Since the maximum
quantity of air per jet lift is limited by the cylinder size,
overinflation of the lung with consequential baro trauma is also
prevented.
[0020] Within the framework of the arrangement as per the
invention, it is possible to use two catheters, wherein one jet
catheter is used to support the inhalation process, and the other
catheter is used for precisely slowing the exhalation process. A
catheter can also be constructed with a double lumen, as intended
in patent claim 8. The double-lumen catheter provides separate
channels for the administration of oxygen in the inhalation process
and in the exhalation process.
[0021] The security of the arrangement is increased through the
provision of additional respiration sensors. These, too, are
sensors which record the patient's spontaneous respiration. These
may, for instance, be affixed to the patient's chest so that
spontaneous respiration can be monitored through a thorax impedance
measurement. Sound or flow measurement at the patient's mouth or
nose is also a possibility. Inhalation or exhalation support is
provided by equalizing the recorded signals from the airway and the
further respiration sensors in a control unit and sending
corresponding signals to the oxygen pump. The additional
respiration sensors guarantee redundant construction and contribute
to the security of the arrangement.
[0022] In accordance with patent claim 10, self-reliant protection
is desired for the airway prosthesis as per the invention. This
possesses a tubular support body with a connector for a catheter,
with at least two sensors which are arranged on the support body.
The airway prosthesis excels in its ability to allow measurement of
the patient's respiration. This permits synchronization of external
respiratory support with the patient's own respiration.
[0023] A sensor is advantageously mounted on the internal wall of
the support body (patent claim 11). Thermistors are regarded as
particularly suitable within the framework of the invention. By
linking the thermistors via a bridge circuit, it is possible to
compensate for temperature differences between the internal and
external thermistors. This double arrangement of the sensors in the
bridge circuit compensates for environmental influences, such as
temperature variations, or also differences which may be caused by
secretions coming into contact with the internal sensor, thereby
producing localized cooling or warming.
[0024] It is furthermore advantageous in accordance with patent
claim 12 if the catheter end is placed within the support body so
that it is parallel to the longitudinal axis of the support body.
This results in directional provision of the oxygen flows in the
direction of the bronchial tract, with laminar flow conditions.
[0025] Furthermore, independent protection is desired for a
catheter as per patent claim 13, whose outflowing end includes at
least one sensor. It is functional to provide at least two sensors
in this location in order to be able to carry out the compensation
of measurement values within a bridge circuit.
[0026] Such a catheter can be introduced into a support body from
the outside. such a support body may, for instance, consist of the
well-known "Montgomery-T-Stent". The catheter is introduced from
the externally accessible segment of the T segment so that
respiration can be supported via the catheter.
[0027] According to the characteristics of patent claim 14, the end
of the catheter possesses a jet nozzle. As already described above,
this can, for instance, be provided by a reduction in the
cross-section of the end. However, it may also consist of a
separate jet nozzle.
[0028] The end of the catheter is preferably bent as intended in
patent claim 15. In this manner, the end which is introduced into
the airway or support body is naturally oriented into the direction
of the bronchial tract, parallel to the longitudinal axis of the
support body.
[0029] The invention is described in further detail by the attached
drawings. The following are shown:
[0030] FIG. 1 The upper body of a patient who is wearing a
respiratory support arrangement as per the invention.
[0031] FIG. 2 A diagram showing the respiratory flow of an
emphysema patient, with and without respiratory support.
[0032] FIG. 3 A technically simplified representation of an airway
prosthesis as per the invention.
[0033] FIG. 4 A further embodiment of an airway prosthesis.
[0034] FIG. 5 Also, in the schema, an oxygen pump belonging into
the arrangement as per the invention, depicting control of the air
flow, as well as a control unit.
[0035] FIG. 6 The end section of a catheter as per the invention,
and
[0036] FIG. 7 the catheter placed into a support body as in FIG.
6.
[0037] FIG. 1 uses P to indicate a patient suffering from lung
emphysema, with overwork and exhaustion of the respiratory pump.
This renders the patient unable to inhale deeply enough. The
exhalation process is furthermore obstructed by limp and collapsing
airways.
[0038] Such a respiration process with inhalation (inspiratorial
flow) and exhalation (expiratorial flow) is shown in FIG. 2 in the
left half of the image. The inhalation curve is identified as E1,
while the exhalation curve is identified with A1.
[0039] To support and unburden the respiratory pump, the patient's
spontaneous respiration is recorded by sensors, and an additional
quantity of oxygen is administered to the lungs at the end of an
inhalation process. This respiration flow is further clarified in
FIG. 2 in the right half of the image. The additional quantity of
oxygen increases the respiration volume during inhalation as shown
in curve E2 by the differential volume which is darkened in on the
upper curve, and identified as E3. The additional oxygen quantity
may possess a volume between 25 ml and 150 ml.
[0040] The patient's exhalation process is furthermore slowed by a
counter-flow. This causes the respiratory flow during exhalation to
shift as shown in the curve which is identified as A2. This
resistance, which specifically counteracts the exhalation flow,
prevents airway collapse during exhalation. This process enlarges
the exhalation volume by the volume which is also darkened in, and
identified as A3.
[0041] This process consequently prevents insufficient respiration
with oxygen undersupply and increased carbon dioxide levels in the
bloodstream. The patient P is significantly more stressable and
mobile, as well as feeling less or no respiratory distress.
[0042] The arrangement which is intended to provide respiratory
support to the patient P includes an oxygen pump 1 which can be
connected to an oxygen source (see FIG. 5) and an airway prosthesis
2, 3 (see FIGS. 3 and 4). In accordance with FIG. 1, the oxygen
pump 1 is part of a compact mobile respiration unit 4. The oxygen
pump 1 and the airway prostheses 2 and 3 are connected via a
catheter 5.
[0043] As FIGS. 3 and 4 show, each airway prosthesis 2 and 3,
respectively, possesses a tubular support body 6 with a connector 7
for the catheter 5. Two sensors 8, 9 are assigned to the support
body 6 in the form of thermistors for the purpose of recording the
patient's spontaneous respiration. Herein, a sensor 8 is fastened
to the internal wall 10 of the support body 6, while the other
sensor 9 is located at the outside wall 11 of the support body 6.
The sensors 8, 9 are connected with a control unit 12 for
activating the oxygen pump 2. The control unit 12 is schematically
shown in FIG. 5 with its entries and exits. As already mentioned,
the sensors 8, 9 are thermistors, that is, temperature dependent
resistors. These are linked in a bridge circuit within the
arrangement, so that the compensation of measurement values between
the inner sensor 8 and the outer sensor 9 takes place in response
to environmental influences.
[0044] It is furthermore shown in FIG. 1 that further respiration
sensors 13, 14 are intended. These are likewise sensors for
recording the spontaneous respiration of the patient P.
Equalization of the measurement values recorded by the sensors 8
and 9, as well as 13 and 14, provide a precise depiction of the
respiratory process of the patient P. Security against erroneous
measurements or failure of one of the sensors 8, 9 as well as 13,
14 is furthermore improved.
[0045] In the airway prosthesis 2 as per FIG. 3, the jet catheter 5
can be introduced into the support body 6 via the connector 7. The
end of the jet catheter 15 which is located within the support body
6 is guided/redirected parallel to the longitudinal axis L of the
support body. The data conduits of the sensors 8, 9 for the control
unit 12 are identified as 16 and 17. These run within the catheter
5. At the outflow end 15, the jet catheter 5 is designed as a jet
nozzle 25. This can be accomplished by a reduction of the catheter
cross-section. This increases the speed of the oxygen flow at the
exit of the catheter 5, directing it into the direction of the
bronchial tract. The diameter of the support body 6 is dimensioned
with a lumen which is sufficiently large so that the patient P can
breathe and speak freely even with the integrated catheter 5.
[0046] In the airway prosthesis 3 as per FIG. 4, a separate
coupling 18 is provided at the connector 7 to connect the catheter
5 to the airway prosthesis 3. In this case, within the support body
6 and parallel to the longitudinal axis L, a fixed length segment
19 is intended as a catheter end, wherein the oxygen flow is
directed into the direction of the bronchial tract via a jet nozzle
26.
[0047] The oxygen pump 1 is schematically shown in FIG. 5. It
involves a cylinder pump with a double-action piston 20 which is
arranged within a cylinder 27. The arrangement possesses a total of
four valves V1 to V4. Oxygen is supplied out of an external oxygen
reservoir via the connector 21. The switching conditions of the
valves V1 to V4, as well as the incoming and outgoing supply lines,
are identified by the letters a to g.
[0048] In respiratory support, the function of the oxygen pump 1
within the arrangement is as follows:
[0049] When the valve V1 from c to a are open (b to c closed) and
the valve V2 from b to e is open (e to d closed), the piston 20 at
the image level moves to the left, and oxygen flows through the
outlet 22 and the jet catheter 5 to the patient P. The additional
quantity of oxygen E3 is administered during the inhalation process
of the patient P.
[0050] When the valve V1 from b to c (c to a closed) is open, and
the valve V2 from e to d is open (b to e closed), the piston 20 at
the image level moves to the right, and oxygen flows out in the
direction of the valve V3. The valve V3 is connected to the outside
air via an outlet 23. If the valve V3 from d to g is open, the
oxygen flows without an expiration resistor: This means that the
exhalation process is not slowed by a counter-flow.
[0051] If the valve V3 from d to g is closed, and is open from d to
f, the oxygen flows in the direction via the supply line 24 to the
outlet 22 and the catheter 5 to be administered to the patient P
during the exhalation process, as well as slowing the respiratory
flow. The counter-flow prevents airway collapse and keeps the
airways open. This enables deeper exhalation.
[0052] In the supply line 24 of the arrangement, the valve V4 is
also switched, allowing variable adjustment of the flow-through (f
to a). This may preferably consist of a proportional valve with
pulse width modulation.
[0053] FIG. 6 shows a catheter 28 with a long, flexible tube 29 and
an outflow end 31 which is angled through the use of a bent segment
30. The end includes two sensors 32, 33 to record the spontaneous
respiration of a patient P. The sensors 32, 33 preferably consist
of thermistors. The representation of data cables has been omitted
for the sake of simplicity. These run through the catheter 28 or
the catheter wall. 34 identifies a stop.
[0054] It is furthermore recognizably shown that the end 31 of the
catheter 28 is provided with a jet nozzle 35. Within the jet nozzle
35, the flow cross-section is reduced relative to the cross-section
of the catheter, so that the exit speed of the supplied oxygen is
increased.
[0055] The catheter 28 may be introduced into a support body 36, as
shown in FIG. 7. The support body 35 is located within the airway
of a patient P. The connection to the outside is provided via a
connector 37.
[0056] The support body 36 may consist of a customary
"Montgomery-T-Stent".
LIST OF REFERENCE SYMBOLS
[0057] 1--Oxygen pump [0058] 2--Airway prosthesis [0059] 3--Airway
prosthesis [0060] 4--Respirator [0061] 5--Catheter [0062]
6--Support body [0063] 7--Connector [0064] 8--Sensor [0065]
9--Sensor [0066] 10 Internal wall, front 6 [0067] 11 External wall,
front 6 [0068] 12 Control unit [0069] 13--Respiration sensor [0070]
14--Respiration sensor [0071] 15--End, front 5 [0072] 16--Data
cable [0073] 17--Data cable [0074] 18--Coupling [0075] 19--Length
segment [0076] 20--Piston [0077] 21--Connector [0078] 22--Outlet
[0079] 23--Outlet [0080] 24--supply line [0081] 25--Jet nozzle
[0082] 26--Jet nozzle [0083] 27--Cylinder [0084] 28--Catheter
[0085] 29--Tube [0086] 30--Bend [0087] 31--End, front 28 [0088]
32--Sensor [0089] 33--Sensor [0090] 34--Stop [0091] 35--Jet nozzle
[0092] 36--Support body [0093] 37--Connector [0094] P--Patient
[0095] E1--Inhalation curve [0096] E2--Inhalation curve [0097]
E3--Volume [0098] A1--Exhalation curve [0099] A2--Exhalation curve
[0100] A3--Volume [0101] V1--Valve [0102] V2--Valve [0103]
V3--Valve [0104] V4--Valve [0105] L--Longitudinal axis, front 5
[0106] a--line [0107] b--line [0108] c--line [0109] d--line [0110]
e--line [0111] f--line [0112] g--line
* * * * *