US 3511228 A
Description (OCR text may contain errors)
May 12, 1970 c. E. G. LUNDGREN ETAL 3,511,228
BRONCHIAL DILATOR FOR PATIENTS SUFFERING FROM EMPHYSEMA AND ASTHMA OR THE LIKE Filed May 28, 1965 PG. I
61445: f G. lu/voeef/v INVENTORS BY v United States Patent 3,511,228 BRONCHIAL DILATOR FOR PATIENTS SUFFER- IN G FROM EMPHYSEMA AND ASTHMA OR THE LIKE Claes Erik Gunnar Lundgren, Stora Tvargatan 36, and Istvan Janos Antal Lichtneckert, Fjelie V. 23, both of Lund, Sweden Filed May 28, 1965, Ser. No. 459,700 Claims priority, application Sweden, June 4, 1964, 6,810/ 64 Int. Cl. A61h 1/00 US. Cl. 128-25 1 Claim ABSTRACT OF THE DISCLOSURE Apparatus for providing controlled assistance to ex halation for a person suffering from certain lung disorders, comprising a nonreturn inlet valve for air that imposes little resistance to inhalation, in combination with two outlet valves for exhaled air. One of the outlet valves is adjustably spring loaded, while the other outlet valve is of the set-screw type, so that rotation of the set screw adjusts the orifice of said other outlet valve.
It is known that pulmonary diseases such as asthma and emphysema cause difficulties in breathing, particularly due to resistance to expiration. It has been elucidated that the basic pathophysiological mechanisms are based partly on simple physical phenomena. Thus, a locking mechanism which makes expiration more difficult arises as the patient while expiring has to overcome the air flow resistance which is present due to pathological changes of the res piratory tract. However, it has been found that patients suffering from the above mentioned diseases may be considerably releived of the breathing difliculties if the patient by his mouth causes a suitable resistance to the flow of air in expiration by pressing his lips together.
The present invention relates to an apparatus which facilitates the technical accomplishment of resistance breathing in the diseases referred to above. It provides an accurately adjustable expiration resistance adapted to individual requirements without any risk for an unfavourable increase of the lung volume (the functional residual capacity) at passive expiration and does not tax the patient by an additional resistance to inhalation. The apparatus enables particularly favourable distribution in the lungs of medicines distributed by inhalation. The apparatus can easily be operated by the patient himself, it operates automatically as the patient breathes, it may be made so small that it can be carried conveniently in the patients pocket to be ready for use, e.g. at an attack of asthma or in case an emphysematic person needs an augmented ventilation of the lungs in connection with a prestation of muscles. Alternatively, the apparatus may be provided with a mouthpiece for breathing through the mouth or with a breathing mask for breathing through the mouth and nose simultaneously.
The invention comprises an apparatus for the purpose referred to, which is substantially characterized by a preferably tubular housing having an opening to be connected to the sick persons mouth, an inlet means for inhaled air, and outlet means for exhaled air, one of said outlet means comprising a preferably spring-loaded or elastic expiration valve and another of said outlet means including an expiration valve having a manually adjustable passage area for exhaled air. The spring-load or elasticity of said yieldable expiration valve may also be adjustable. Said expiration valves have resistance characteristics differing one from the other. The spring-loaded or elastic valve has a static resistance characteristic allow- 'ice ing escape of a large quantity of exhaled air and being capable of keeping the desired resistance to expiration constant as long as the pressure in the lungs is maintained and which in this connection acts indepedently of the magnitude of the gas flow. The adjustable expiration valve or leakage valve acts as a dynamic resistance and has a relatively low capacity of flow during the greater part of the expiration phase as compared with the static resistance valve. The combination of the two types of resistance enables contracted air pipes in the lungs to be opened, but provides that an increase of the functional residual capacity may be avoided. The latter effect results from by the fact that the last part of the expiration (as the gas flow is beginning to be reduced and the static resistance valve is closed) escapes by way of the dynamic resistance which decreases with a decreasing flow. (It is to be noted that a dynamic resistance alone would not be sufiicient since its magnitude would vary to a high degree as the gas flow varied which would result in that a dynamic resistance adapted to breathing at rest would place too much strain on the patient during heavy breathing.) Furthermore, it is to be noted that the inhalation valve is easily operable and has a great flow capacity.
The invention will be more particularly explained by description of embodiments thereof as illustrated in the accompanying drawing, in which FIG. I is a diagrammatic longitudinal section of a model illustrating the function of the resistance and the locking mechanism of the expiratory tracts, FIG. II shows a longitudinal section of the apparatus proper and FIG. -III is an elevation of a modification of the apparatus.
The function of the locking mechanism is illustrated in the diagrammatic FIG. I in which 1 is a bladder corresponding to lung parts containing air, 2 is an air pipe which has a restriction 3 in its end opening in the interior of the bladder said restriction corresponding to the pathological change. The other free end is carried out through the wall of the bladder and has its mouth outside the free end 4. The tube 2 consists of an elastic material having qualities corresponding to those of the respiratory tracts of the lungs.
As the bladder 1 is to be exhausted (expiration) this is effected by applying pressure by way of its walls to the gas therein (corresponding to the action of the expiratory constrictors or the elastic force of the bladder). It may then occur that the applied pressure compresses the tube 2 as indicated by the dotted lines 5 so that the exhaustion is difficult or impossible.
The locking action at 5 in FIG. I may be reduced if a resistance 6 of a suitable shape is arranged at the end 4 of tube 2. As a result, the resistance to the gas passage at 6 when it is sufficiently large as compared with the resistance at 3 generated by the sickness prevents further restriction of tube 2. However, a method which presumes that the patient himself shall positively generate the described eifect necessitates that he has been paricularly instructed and trained in the breathing technique, and this is difiicult to apply with the necessary accuracy if he suffers from orthopnaea.
From reasons to be developed more in detail hereinafter, the resistance at 6 in FIG. I should be of a constant character (static). However, this type of resistance has an unfavourable effect in one respect. The respiratory members can be compared with an elastic bag which is expanded during inhalation through forces (from the inhalation muscles) actuating its walls outwardly. If during expiration no muscular members are made active the ex piration takes place by the fact that the activity of the inhalation muscles ceases and the bag contracts due to its elasticity. If there is a resistance of a character independent of the flow (static resistance) against the respira- 3 tion, the latter is interrupted as the volume of the bag has been reduced to such an extent that a balance has arisen between the elastic force therein and the resistance. Thus, in case of exterior static resistance against breathing there is an acting mechanism which in itself prevents complete emptying of the lung. The functional residual capacity of the lung thus increases which is unfavourable to the efliciency of ventilation.
In certain pathological conditions of lungs it is customary to supply medicines in a spray form or as vapor carried by inhaled air. Thus, for instance, in case of bronchial asthma bronchodilating means such as adrenaline is supplied. The intention by such treatment is to actuate the contractedair pipes by the substance directly and locally. In this connection there is a diificulty connected with the condition indicated hereinbefore, viz., that the lung parts which are supplied by way of the contracted air pipes become more difficult to exhaust due to the locking mechanism so that these lung parts also to a less extent receive inhaled air and the active substances which are distributed and which they need.
FIG. II illustrates an embodiment of the invention in which a housing or tube 1 has one end thereof provided with a mouthpiece 2 and its other end with an inhalation valve comprising a flap valve 3 consisting of a diaphragm of rubber centrally secured to a spider member 4' and arranged so that the flow of air may pass thereinto from the end 5 toward the mouthpiece. Further, the tube 1 has an expiration valve 13 at a lateral orifice 6' with a valve seat 7 surrounded by a valve housing 8 at both sides provided with gas ports 9. Resting on the valve seat is a rigid valve disc 10 which is actuated from above by a pressure spring 11 having its upper end actuated by a set screw 12 which is rotatably inserted in the top of the valve housing 8 and on rotation is displaced along its axis of rotation. The pressure of opening of the expiration valve 13 is adjustable from 0 to about 40 cm. (15.7") of water.
. There is a dynamic resistance valve in the wall of tube 1' at an orifice 14, the rim of which serves as a valve seat for a set screw 15 having screw engagement with a screwthread in the tube 16 and thus enabling variation of passage area of the valve orifice. Air passage of varying rate through the lateral hole 17 on the tube 16 may thus be obtained.
Alternatively, the mouthpiece 2 may be replaced by a breathing mask of conventional type (18 in FIG. III) which has a close fit around mouth and nose.
In operation of the apparatus the patient seizes the mouthpiece 2' by his lips (alternatively he applies the mask 18), whereupon the dynamic resistance or leakage valve 14 is closed and he breathes in and out through the apparatus and experimentally adjusts the spring pressure on the valve disc 10 upwards or downwards by the set screw 12 until the maximum of relief is obtained during expiration. After this the valve 14 is opened as much as possible with a continuing feeling of relief during breath ing. Inhalation occurs by way of the inhalation valve 3' without any particular resistance.
FIG. III illustrates an embodiment of the invention in which the previously described pneumatic bronchodilator is provided with a connection member 19 beyond the inhalation valve and/or a similar connection member 20 inside the inhalation valve adapted to be connected to the inhalation tube of a spray device or the like which is employed to supply medical substances to the lungs in inhaled air.
In operating the apparatus one breathes in the bronchial dilator before or during supply of efiective means and thus ensures that the lung parts which are expanded by the locking mechanism in the manner previously described are exhausted by the expirations and receive a greater part of the active substance than would otherwise be the case. If the spray device or the like, due to its construction, is provided with its own expiration resistance (non-return valve action or the like) it should be suitabl connected according to the alternative 20 or otherwise according to 19.
If in the alternative 20 the bronchial dilator is used without the spray apparatus or the like, the connection 20 should be closed by a plug of rubber or the like.
What we claim is:
1. Apparatus for providing controlled resistance to exhalation for persons sufiering from lung disorders, comprising a main housing having an opening to be connected to a persons mouth, nonreturn inlet valve means for admitting inhaled air, and outlet valve means for expelling exhaled air, said outlet valve means imposing substantially more resistance to exhalation than said inlet valve means opposes to inhalation, said outlet valve means comprising a pair of valves, a valve housing on the side of said main housing, one of said valves being disposed in said valve housing, a coil compression spring that urges said one valve closed to separate said valve housing from said main housing, said one valve opening under pressure of exhaled air against the action of said coil compression spring, said valve housing having outlet ports through the walls thereof, a screw that passes through a screw-threaded opening through one wall of said valve housing and that bears adjustably on said coil compression spring to adjust the magnitude of force with which said one valve opposes exhalation, the other of said valves comprising a tube that opens into said main housing through a passage disposed axially of the tube, said tube having a lateral outlet for expelled air, a set screw screw-threadedly disposed axially in said tube, said set screw having an inner end that is movable axially in said tube to vary the size of the passageway between the main housing and said lateral outlet.
References Cited UNITED STATES PATENTS 635,232 10/1899 Carroll 27257 864,908 9/ 1907 Nebelthau 1282.08 940,735 11/1909 Schoeffer et al 272-57 WILLIAM G. KAMM, Primary Examiner