BR0101104B1 - PRESSURE ADJUSTMENT DEVICE AND BREATHING AID - Google Patents

Description

Report of the Invention Patent for "PRESSURE ADJUSTMENT DEVICE AND RESPIRATION AID".

FIELD OF THE INVENTION The present invention relates to the use of a pressure regulator in conjunction with a respirator, particularly not only to regulate the pressure of gases delivered to a patient from an Expiratory Pressure apparatus. Positive End Point (PEEP).

Background of the Invention The use of a medical device to facilitate breathing is well known in the art. The apparatus may be in the form of a simple oxygen mask or tent which supplies oxygen at a pressure slightly above atmospheric. Such devices merely help a person breathe and work with the person's lungs.

Fans operating at high frequency have been suggested in the past. There are two types of high frequency fans known in the art. One type, as exemplified by U.S. Pat. No. 2,918,917 (Emerson) employs an oscillating diaphragm to vibrate a gas column supplied to a subject. Vibration is in addition to subject breathing, natural or artificial, and at a much faster rate, for example from 100 to over 1500 vibrations per minute. Emerson's device is primarily designed to vibrate the patient's airway and associated organs, although Emerson also recognized that high-frequency vibration causes gas to diffuse faster into the airways. airways and therefore aids in the function of breathing. However, Emerson's device is unable to sustain the patient's total ventilation and should be used in conjunction with the patient's spontaneous breathing or with another device which produces inhalation and artificially induced exhalation. The second type of high frequency fan is the jet pulse fan as exemplified in Pat. No. 4,265,237 (Schwanbach et al.). The fan of Schwanbom et al. produces high-frequency, high-pressure air pulses that are able to fully ventilate a patient. The breath pulse enters a pressure from 0,2 bar to 2,7 bar.

This pressure is sufficient to expand the lungs during inspiration. Exhalation is caused by the natural contraction of the lungs after the air jet is stopped. Consequently, it can be seen that Schwanbom et al. You should rely on the contraction of the lungs to fully ventilate the patient.

If lung contraction is low, higher pressure should be used.

Schwanbom et al. It also provides a lower pressure gas source for spontaneous breathing by the patient. While jet pulse fans are useful for some applications, they are not generally applicable and their use is limited mainly to experimental work.

An improvement on these types is described in U.S. Pat. No. 4,821,709 (Jensen) which provides high frequency oscillations in the gases delivered to a patient using a flexible diaphragm. Jensen provides a more practical method for ventilating a patient without the patient's spontaneous breathing or the need for a separate ventilator. THE

Pat. No. 4,646,733 (Strot et al.) proposes an apparatus for producing high frequency oscillations in the gases delivered to a patient using a valve that controls the exhaled gases.

It would be desirable to have a simple system to provide high-frequency pressure oscillations for spontaneously breathing patients, particularly for non-invasive forms of support, where the average level of patient-supplied gases can be adjusted.

Description of the Invention It is an object of the present invention to provide a pressure regulator which in some way overcomes the above mentioned disadvantages, or which will at least provide the health care industry with a useful choice.

Accordingly, in a first aspect, the present invention consists of a pressure regulating device for use with a breathing aid apparatus which transports inhalant gases to and removes exhalation gases from a patient requiring assistance. comprising or including: a container which in use includes a body of liquid, a terminal conductive means including the nearest and most distal ends, said proximal end adapted for connection to a breathing aid apparatus and in use. accepting his exhalation gases, and said far end submerged in said body of liquid, such that in use the mean pressure of said inhaled gases supplied to a patient is adjusted by the level at which said far end is submerged in said body of liquid.

In a second aspect, the present invention is a breathing aid apparatus for supplying the gases to a patient to assist said patient breathing including: a gas supply means adapted to supply the gases to said patient, a means of a supply comprising a plurality of openings adapted to supply said gas flow to said patient, a means of conveying inhalant gases to transport said gas flow from said gas supply means to said delivery means, a means of conveying the exhaled gases for conveying said patient exhales of said supplying means, and a pressure regulating device disposed within or in fluid communication with said means of conveying the exhaled gases, said a pressure regulating device comprising or including: a container which in use includes a body of liquid, and a terminal conductive means including including the nearest and most distant ends, said near end in use connected to said exhalation gas transport means and accepting said patient exhales from it, and said far end submerged in said body of liquid, such that in use the mean pressure of said inhaled gases provided to said patient is adjusted by the level at which said far end is submerged in said body of liquid.

In a third aspect, the present invention is a pressure regulating device for use with a breathing aid which in use conveys the inhaled gases to and removes the exhaled gases from a patient who requires breathing aids. comprising or including: a container which in use includes a body of liquid, and a terminal conductor means including the nearest and most distal ends, said proximal end adapted for connection to a breathing aid apparatus and accepting the exhalation gases, and said distal end submerged in said body of liquid, such that in use the resulting bubbling occurring in said body of water produces relatively small controlled disturbances in the pressure of the inhaled gases delivered to a patient.

For those skilled in the art to which the invention relates, many changes in construction and widely different embodiments and applications of the invention will suggest without departing from the scope of the invention as defined in the appended claims. The presentations and descriptions herein are purely illustrative and are not intended to be limiting in any way.

BRIEF DESCRIPTION OF DRAWINGS

Figure 1 is a block diagram showing a typical configuration for providing a breathing aid to a patient; Figure 2 is a plan view of the pressure regulator with the cap according to the preferred embodiment of the present invention; Figure 3 is a side view of the pressure regulator according to the preferred embodiment of the present invention, Figure 4 is a cross section of the pressure regulator according to the preferred embodiment of the present invention, Figure 5 is an alternative side view of the pressure regulator According to the preferred embodiment of the present invention, Figure 6 is a perspective view of the short conductor extending into the water chamber according to the preferred embodiment of the present invention. Figure 7 is a cross section of the regulator. pressure gauge according to the preferred embodiment of the present invention, and Figure 8 is a cross-sectional view of an additional embodiment of the present invention. dog.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention provides a means for producing variations or oscillations in gas pressure delivered to a patient connected to a positive pressure venting device. By submerging the end of the exhalation conductor in a column of water, the resulting bubbles generate a variation or a ripple in the mean pressure of the gases delivered to the patient. In so doing, it also provides a simple method for varying the mean pressure of the gases delivered to the patient by varying the level at which the exhaled conductor end is submerged within the water column. In order to keep the mean pressure of the gases supplied to the patient constant, the level of submergence of the exhaled conductor end must be kept constant and an apparatus to ensure this occurs is also described.

Referring now to Figure 1 in which a typical application is presented. A humidified Positive End Expiratory Pressure (PE-EP) system is shown in which a patient 119 is receiving humidified gases 114 and pressurized through a nasal mask 128 connected to an inhaled conductor 121. It should be understood that the present invention However, it is not limited to the supply of PEEP gases but is also practicable for other gas supply systems and may not necessarily involve humidification. Inhaled conductor 121 is connected to outlet 112 of a humidification chamber 110 which contains a volume of water 115. Inspiratory conductor 121 may contain heating means or heating wires 120 which heat the conductor walls to ensure a constant moisture profile throughout the conductor and thus reduce condensation of humidified gases within the conductor. As the volume of water 115 within the humidification chamber 110 is heated 113 the water vapor begins to fill the chamber volume above the water surface and is passed out of the output 112 of the humidification chamber 110 with the flow of water. gases (e.g., air) supplied from a gas supply means or fan 118 which enters chamber 110 through inlet 116.

Humidified gases pass through the inhaled lead 121 to the mask 128 attached around the patient's mouth 119. Excess gases then flow through the exhaled lead 130 to a pressure regulator 134.

PRESSURE REGULATOR

In the preferred embodiment of the present invention pressure regulator 134 takes the form of discharging the flow of exhaled gases into a chamber 204 containing a column of water 138. Gases flowing through the exhaled conductor 130 are discharged into the body of water 138 from a short conductor 136 which extends from the expiratory conductor into chamber 204. This results in a bubbling effect whereby gases eventually exit chamber 204 via outlet port 152, which It may also be used to initially fill the chamber 204 with water. Outlet opening 152 includes a shield to prevent liquid aerosols created by the vigorous bubbling over the surface of the water from being expelled. It will be appreciated that the short conductor 136 could also be integrated into the end of the expiratory conductor 130.

Referring now to Figures 2 to 7, pressure regulator 134 and associated components are seen in greater detail. The exhalation conductor (130, Figure 1) fits into the end of the short conductor 136 which in turn is attached to the water chamber cover 144 via connector 146. Connector 146 includes a number of resilient or straight ribs. plastics 148 which lock into the annular channels 150 in the short conductor 136 to keep it locked in a desired position during use. Chamber 204 is filled with a body of water 138 to a predetermined level 140. It will be appreciated that any suitable liquid could be used instead of water.

It will be appreciated that for control over the mean pressure of the delivered gases it is necessary to vary the level at which the short conductor 136 is submerged in the body of water 138. Staggered variations in patient delivered gas pressure of Vi cm H20 each, are suitable for most applications and are achieved by spacing each of the annular channels 150 of Vt. cm. A contoured handle portion 147 is provided at the end of the short conductor 136 which engages with the exhalation conductor 130 to allow for easy adjustment. In one embodiment, the pressure is adjustable over a 4-8 cm range of H2 O but it will be appreciated that this can be modified as required. The pressure regulator according to the preferred embodiment of the present invention is shown in Figure 7, adjusted to its highest pressure position. Positions may be indicated by a number above each channel 150 over short conductor 136, which would be visible above connector 146.

CONSTANT WATER LEVEL

In the preferred embodiment, the present invention is used in conjunction with a humidified PEEP respirator. As such, the exhaled gases will have very high humidity levels, some of which will inevitably condense in the body of water 138 within the pressure regulator 134. Thus, over time the volume of water inside the water chamber 204 will rise and if not checked will result in increased gas pressure delivered to the patient with the resulting adverse side effects. To ensure that the water level is kept constant the water chamber 204 is equipped with an overflow equipment 218 also seen in Figures 2 to 7.

Due to the vigorous bubbling that occurs at the top of the body of water a simple lip over which excess liquid can flow would be inefficient and therefore some form of filtering or damping is required. In order to mitigate the effect of vigorous bubbling near the top of chamber 200, a main outlet opening 202 of main chamber 204 is provided at a substantially lower level than where bubbles would normally be expected to occur. However, the bubbling also causes pressure waves through the body of the liquid. These pressure waves would normally be reflected through the main outlet port 202 into the leveling chamber 206 and thus would result in more water escaping than is desirable. To alleviate the effects of pressure waves a wave guard 208 is located in an intermediate position between the upper water level 210 and the main outlet opening 202. This masks the outlet opening 202 of most of the waveforms. pressure due to surface bubbling.

This effectively means that the water level within the leveling chamber 206 is relatively calm and substantially representative of the average (as opposed to instantaneous) water level within the main chamber 204. The water level within the intermediate overflow chamber R 206 is in turn regulated by an overflow aperture 212 situated on an adjacent elevated platform 214. The overflow aperture 212 is surrounded by a slightly raised cylindrical partition 216 to overcome the effect of any small waves. remnants within the intermediate overflow chamber 206. Water then flows into the detachable overflow container 218 which when filled can be detached in use and emptied. Both the main chamber 204 and the intermediate overflow chamber 206 are integrally injection molded using a clear plastic. The separate overflow container 218 is also injection molded using a clear plastic as is the separate short conductor 136.

ADDITIONAL MODES

It will also be appreciated that the apparatus used to vary the average water level within the main chamber may take a number of forms. While in the preferred embodiment a sliding conductor is used, other forms such as a concertina damper or a rotary conductor, for example, would also apply. It will also be appreciated that additional forms of the overflow facility will be possible.

For example the additional embodiment shown in Figure 8 utilizes a thin slit 162 to pass water into a second chamber 160, whereby dampers 164 smooth out any variations before the overflow aperture 166 into the overflow chamber 168.

ADVANTAGES - Allows easy adjustment of the mean pressure level. - Allows high frequency pressure oscillations for spontaneously breathing patients. - Maintains a constant average pressure with little or no maintenance. - Disposable or economical compared to prior art fans.

Claims (9)

1. Pressure regulating device (134) for use with a breathing aid apparatus which carries inhalation gas to and removes exhalation gas from a patient requiring breathing aid comprising: a container (204) which, in use, includes a body of liquid (138), wherein the container is configured to have a constant level in use, a terminal conductor means (136) including the nearest and farthest ends, the proximal end adapted to connected to a breathing apparatus and, in use, admitting the exhalation gases thereof, and the distal end submerged in the body of liquid (138), so that, in use, the mean pressure of the delivered gas to a patient is adjusted by the level (140) at which the farthest end is submerged in the body of liquid, and wherein the pressure regulating device is provided in line with and downstream of the patient's exhalation gases; characterized in that it further comprises an overflow means (218) which maintains the constant level of the liquid body (138) in the container (204) when in use. Pressure regulating device according to Claim 1, characterized in that it further comprises a connection means (146) attached to the container (204) and coupling the terminal conductor means (136) by means of that in use the terminal conductor means (136) may be adjusted axially in predetermined increments relative to the connection means (146). Pressure regulating device according to claim 2, characterized in that the terminal conductor means (136) further includes at least one partial channel (150) and the connection means (146) includes at least least one corresponding partial resilient rib or fin (148). Pressure regulating device according to Claim 2 or 3, characterized in that the predetermined increments are one centimeter each. Pressure regulating device according to Claim 1, characterized in that the overflow means also includes a damping means (216). Pressure regulating device according to Claim 5, characterized in that the damping means (216) includes a submerged outlet (202) from the container (204) which is located in the housing. a position which in use is below level (140) of the liquid body (138), and a means for reducing the output pressure waves produced in use within the liquid body by the patient's exhales flowing through it located in a position which in use is between the level (140) of the liquid body and the submerged outlet (202). Pressure regulating device according to any one of claims 1, 5 or 6, characterized in that it further comprises a removable container, whereby the overflow from the liquid body (138) is in use. ) flows through the overflow outlet into the removable container. Pressure regulating device according to any one of Claims 1 to 7, characterized in that the body of liquid (138) is composed of water. Pressure regulating device according to any one of Claims 1 to 8, characterized in that the device (134) is made of transparent plastic material.