US 3079915 A
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Description (OCR text may contain errors)
March 5, 1963 P. L. STANTON RESUSCITATOR 2 Sheets-Sheet 1 Filed July 14, 1958 INVENTOR.
P/U/ L. $779570 5/ Ma A777OE/VE4 March 5, 1963 P. STANTON 3,079,915
RESUSCITATOR Filed July 14, 1958 2 Sheets-Sheet 2 INVENTOR.
FIG: 7. 4 (aw United States Patent 3,679,915 RESUSCETATGR Philip L. Stanton, 389 Flintridge Galas, Pasadena, Calif. Filed July 14, 1958, Ser. No. 748,422 2 Claims. (Ql. 123-29) This invention relates to resuscitators of the pulmometric type.
Heretofore attempts to administer artificial respiration with such resuscitators, to tiny premature infants and small animals having very small trachea or air passages to the lungs, in many instances have failed, due primarily to the fact that the volume of gas directed for delivery to the lungs of the patient is still too great to be accommodated by such small air passages even when the resuscitators are adjusted to operate at the slowest respiratory rate.
if these resuscitators are adjusted to provide a how rate that will be accommodated by such small trachea or air passages, this reduced flow will be ineffective to produce the cyclical operation ne essary for proper resuscitation. Accordingly, it is apparent that resuscitatcrs heretofore available have not been suitable for administering artificial respiration safety to infants and animals having very small trachea.
In the use of these resuscitators for treating such small patients, the resistance to the flow of gas caused by the small trachea results in a premature build up of pressure in the resuscitator that will cause reversal of the mechanism thereof and eifect the exhalation cycle before the gas has properly inflated the lungs. Likewise during an exhalation cycle, the small trachea will cause reversal of the resusciator mechanism to the inhalation cycle before the lungs of the patient have been evacuated. Failure of proper artificial respiration may also take place where the patients trachea is obstructed to the extent precluding accommodation of a gas flow suificient to produce efficient resuscitation.
it is an object of this invention to provide a novel resuscitator control unit which may be employed as an attachment for a pulmometrically controlled resuscitator or as an integral part thereof to render the resuscitator subject to efficient and reliable use in administering artificial respiration to small premature infanats and small animals, as well as to patients whose air passages are obstructed to the extent that would prevent resuscitation with resuscitators heretofore available.
it is another object of this invention to provide a control unit such as described which makes it possible to administer artificial respiration to small infants and animals having small trachea, in that the volume of flow of gas to these patients may be reduced below that afforded by the control usually provided on the resuscitators, without interfering with proper cyclical operation of the resuscitator to produce the desired inhalation and exhalation phases. In other words the control afforded by the present invention makes it possible to operate a re suscitator at a slower respiration rate than heretofore whereby artificial respiration may be administered with safety to patients of the type above noted.
it is another object of this invention to provide an improved pulmometrically controlled resuscitator which makes it possible to administer artificial respiration with complete safety and desired results not only to adults and children having trachea of normal size but to premature infants and small animals having very small trachea as well as to persons having seriously obstructed trachea.
Another object is to provide a resuscitator such as described which may be used in a reliable manner to resuscitate or effect controlled breathing of very small infants and animals during surgery.
?atented Mar. 5, 1953 An additional object of this invention is to provide a resuscitator control unit such as described wherein means including an expansible chamber and passage means affording communication of this chamber with the gas flow circuit between the resuscitator and the patient, makes possible the objects and advantages herein noted.
Another object of this invention is to provide a control unit such as described, of simple construction and arrangement which readily lends itself to embodiment in any suitable manner in various types of pulmometrically controlled resuscitators, provided it will afford communication of the expansible chamber thereof with the fiow circuit between patient and the resuscitator during the inhalation and exhalation phases of operation of the resuscitator.
It is another object to provide a resuscitator control unit such as described which readily may be adjusted to change the respiration rate of a resuscitator over a wider range than possible with controls hereto-fore provided.
A further object hereof is to provide a resuscitate: which makes possible efficient use of extremely small endo-tracheal tubes that may be required for intuba tion of tiny premature infants and newly born puppies, kittens and other small animals, it being possible to effect the desired artificial respiration through a tube having an internal diameter less than one millimeter.
it is an additional object to provide an improved resuscitator of the character described wherein a novel auxiliary expansion chamber is arranged to expand and contract in response to the inhalation and exhalation phases of the resuscitator in such a manner that cessation of the inhalation phase will not take place until the patients lungs and the auxiliary chamber are supplied with gas in the amount required for desired insufilation of the lungs, regardless of the small size of the trachea of the patent; and wherein during an exhalation phase, the cessation of this phase also will not take place until the auxiliary chamber and the patients lungs are evacuated as desired, thereby preventing the objectionable premature phase changing of the resuscitator which occurred in some uses of resuscitators as heretofore employed.
Other objects and advanta es of the invention will be hereinafter described or will become apparent to those skilled in the art, and the novel features thereof will be defined in the appended claims.
The invention will be more readily understood upon reference to the accompanying drawing, wherein:
PEG. 1 is a side elevation of a resuscitator embodying the present invention, with portions broken away for clarity of illustration;
FIG. 2 is an enlarged sectional view taken on the line 2-2 of FIG. 1;
PEG. 3 is a sectional view taken on the line 3-3 of FIG. 2;
F16. 4 is a fragmentary sectional view taken on the line 4-4 of FIG. 2;
FIG. 5 is a sectional View corresponding to PEG. 3 showing parts of the resuscitator in a different position than in PEG. 3;
FIG. 6 is a fragmentary sectional view taken on the line 6--6 of FIG. 2;
FIG. 7 is a sectional view taken on the line 7--7 of KG. 2;
FIG. 8 is an enlarged fragmentary longtiudinal sectional view of the auxiliary expansion chamber unit; and
PEG. 9 is a side elevation of a modified form of this invention.
In the accompanying drawing, there is shown a resuscitator of the type in which the present invention may be embodied, it being understood that the invention may be embodied in various types of pulmometrically controlled resuscitators.
Before describing in detail the construction of the resuscitator here shown, it should be noted that it embodiesin accordance with this invention a control unit 1 which includes an expansi'ble chamber 2 and conduit or passage means 3 whereby the chamber may be communicated with the resuscitator or parts thereofso as to be in the gas flow circuit'between the resuscitator and the means for communicating the resuscitator with the lungs of a patient. Connected in this manner the chamber 2 will expand and contract during the inhalation and exhalation phases of the resuscitator and becomes in efiect, an enlargement of the lungs of the patient. Accordingly, on the inhalation cycle the chamber 2 expands and this cycle continues until the chamber and the lungs are supplied with gas necessary to eflect desired inflation of the lungs. When the pressure in the lungs and chamber 2 reaches the predetermined value at which the resuscitator is set for reversing to the exhalation cycle, the resuscitator mechanism then effects the exhalation cycle.
During the exhalation cycle the chamber 2 must be evacuated as well as the patents lungs before the resuscitator reverses to the inhalation cycle.
The control unit 1 includes a cylindrical housing 4 made of a light metal or other suitable light material for enclosing an elongated elastic bag 5 which forms the expansion chamber 2. The bag 5 is closed at one end and open at the other end, the open end being closed by a plug 6 which also closes one end of the housing and is secured thereto by means of fastenings 7. Suitable sealing meansd is provided between the plug 6 and the bag 5. The other end of the housing 4 is closed by a plug 9 held in place by fastenings 10. A vent hole 9 is provided in the plug 9 to permit air'to escape from the interior of the housing.
The passage or conduit means 3 includes a nipple 11 on the plug 6, a port 12 leading from the nipple through the plug into the bag 5 and a hose line 14 for communicating the bag 5 with the flow circuit between the resuscitator and the lungs of a patient.
It should be noted that the bag 5 is formed of rubber or other elastic material and of a thickness and nature making the bag form-retaining whereby upon evacuation of gas therefrom the walls will not completely collapse so as to interfere with inflation of the bag. The bag is di-t mensioned with respect to the housing 4 so that it has sufficient clearance to expand freely laterally and axially.
An adjusting means may be provided to vary the effective capacity of the bag 5 inasmuch as this adjustment makes it possible to vary the respiratory rate of the resuscitator.
As here shown the adjusting means for the bag 5 comprises a disk 16 bearing against the closed end of the bag and movable axially in the housing in response to an adjusting screw 17 mounted in the plug 9. The position of the disk 16 with respect to the plug 9 determines the action of the bag and determines the effective capacity of the expansible chamber 2 formed by the bag.
One convenient way in which the control unit 1 may be embodied in a resuscitator is shown in FIG. 1 and consists in supporting the unit from the gas supply line 18 leading from the source of supply ofgas not shown, to the resuscitator. For this purpose, suitable clamps 19 may be employed. to releasably mount the unit '1 on the line 18, with the hose line 14 extending to the resuscitator.
The resuscitator is illustrated in detail in FIGS. 2 through 7 inclusive in order that it may be understood how the control unit 1 provides for control and modification of the operation of the resuscitator. In this connection it should be noted that 'valve means may be pro-.
With reference to FIGS; 2 and 3, it willbe seen that the resuscitator comprises a sectional body in which the a plate like sections 21 and 22 are held in assembled relation by fastenings 23. A domed cover 24 encompasses these sections and provides a compartment 25 above the upper section 21, there being an atmosphere vent hole 25' in the cover.
The gas supply line 18 is coupled to an intake fitting 26 on the body section 21 as shown in FIGS. 2 and 7.
Gas under pressure passes through the fitting 26 into an intake passage 27 which extends across the body section 21 to a needle valve 23 operated by a knurled handle 29 on the exterior of the resuscitator to control the how of gas thru the resuscitator.
From the passage 27 the gas passes through a port 36 (FIGS. 2 and 7) into a valve chamber 31 formed (-see: FIGS. 3 and 7) complementally in-the sections 21 and 22'.- A valve unit comprising valve members 32 and33 on a:- common stem 34 is mounted in the chamber 3h; The stem 34 is slidable through section 2-1 and extends into the compartment 25 where his connected with a springloaded toggle unit 35. move the stem 34- with a snap action to seat and unseat the valve members 32 and 33, by means of fluid pressure responsive means here shown as a small piston 36 reciprocable in a bore 37 in the section 21.
From the valve chamber 31 gas under pressure may flow through a port 38 (FIG. 3) into a main chamber 397 in the section 22 or flow through a port 38 (FIGS. 3 and 4) to gas operated jet pump means which latter, as here shown, includes a venturi passage 40 extending across the section 21 and vented to the atmosphere through a port 41.
The lower body section 22 is provided with a port 42 which opens into the main chamber 39 and provides forcommunication of this main chamber with the patient through a mask, not shown, or through any other suitable gas administering means such as the endo-tracheal tube 43.
'As here shown, the main chamber 39, has a control. port 44 to which is connected a nipple 45 in il n connected thru the hose line 14 with the control unit 1.. This connection places the expansion chamber 2 of the; control unit 1 in the flow circuit between the resuscitaf-fi and the patient whereby the chamber 2 constitutes in effect an enlargement of the main chamber and the lungs of the patient.
It should be noted that the ends of the piston 36 in the bore 37 are exposed to the compartment 25 and main chamber 39 respectively, so as to effect reciprocal movement of the piston and consequent operation of the toggle unit to actuate the valves 32 and 33, in response to differential pressures in the compartment and main chamber respectively. The valve 32 controls the main chamber port 38, whereas the valve 33 controls the venturi passage port 38'. V
The venturi passage 40 of the jet pump means here shown is provided with a jet nozzle 47 which directs a jet of gas past a combined suction and discharge port 48 (See FIGS. .6 and 2) into the venturi throat 40' of the passage 40. When this venturi 'jet nozzle 47 is in opera-- tion a negative or subatmospheric pressure is created in the port 48 and main chamber 39 to effect the exhalation phase of operation of the resuscitator. During this exhalation phase the gas evacuated from the patients lungs upon entering the chamber 39 will pass through the port 48 and venturi passage 40 to the atmosphere.
Means are provided whereby this resuscitator may be operated solely to produce a continuous inhalation or msufilat'ron operation and as here shown includes a platelike baflle member 50 fixed to the under side of the body section 21 so asto restrict flow of gas through the port 48 to the atmosphere. The amount .of this restriction to be 'efiected is determined at the time of assembling and testing the resuscitator by the manufacturer, and themember 37 is fixed in a predetermined position, partlycovering the port 48. i i
This-toggle unit is operated When the control valve 28 is opened sufiiciently to permit the flow of gas required to cyclically operate the resuscitator for producing the inhalation and exhalation phases, the amount of gas escaping to the atmosphere through the restricted port 48 from the main chamber 39 does not efiect continuation of this cyclical operation. However, if the valve 28 is adjusted to appreciably reduce the gas flow into the resuscitator, this reduction and the rate of escape of gas through port 4-8 makes the pressure in the chamber 39 inefiective to cause the piston 36 and associated means to shift to the position for producing the exhalation cycle, thereby causing a continuous flow of gas to the patient. During this use of the resuscitator the valve 29 on the hose line 14 is closed to render the control unit 1 inoperable inasmuch as this control unit is not required except when the resuscitator is operated cyclically to administer artificial respiration to small infants and animals having trachea of the small size hereinbefore referred to.
In the operation of the resuscitator for administering artificial respiration to small infants and animals, with the control unit coupled in the gas flow circuit between to resuscitator and the patient, as here shown, the control valve 28 is adjusted to provide the desired respiration rate insofar as this is controllable through the setting of this valve. Gas under pressure now entering the intake passage 27 flows through the port 3% into the valve chamber 31. Assuming that the piston 36 is in the down position shown in FIG. 3, so that the valve member 32 is unseated and opens the main chamber port 38 whereas the valve member 33 is seated and closes the venturi passage port 38', gas under pressure will now flow through the passage 38 into the main chamber 39, thence through the port 42 and endo-tracheal tube 43 into the lungs of the patient. At this time gas from the main chamber also flows through the control port 44 and the hose line 14 into the expansible chamber 2 of the control unit ii. The adjusting screw 17 may be operated to move the disk 16 so as to move the closed end of the elastic bag 5 inwardly or outwardly to vary the capacity of the chamber 2 formed by the body and thereby vary the respiratory rate of the resuscitator.
As the expansible chamber 2 formed by the bag 5 in efiect increases the capacity of the patients lungs as well as the capacity of the main chamber 39 in the resuscitator, it is apparent that the inhalation cycle will continue until the chamber 2, lungs of the patient and the main chamber 39 develop a pressure such that the resultant pressure in the main chamber 39 becomes effective for moving the piston 36 upwardly. This causes the toggle mechanism 35 to move the valve stem 34 so that the valve member 32 closes the main chamber port 38 and valve member 33 opens the venturi passage port 38'. Gas now enters the venturi passage 49 and passes through the jet nozzle 47 so as to create a subatmospheric pressure in the port 48 and main chamber 39, thereby etfectin-g the exhalation cycle. During this cycle the gas must be evacuated from the expansion chamber 2 and the lungs before a negative pressure is developed in the main chamber 39 sufiicient to permit atmospheric pressure in the compartment 25 to move the piston 36 downwardly and thereby cause the resuscitator to again operate on the inhalation phase.
The time required to fill the expansible chamber 2 with gas and to evacuate it makes it possible for the resuscitator to be operated at a slow respiratory rate such that the tiny trachea of the patient will pass the gas to and from the lungs in a manner assuring the administering of efiective artificial respiration.
As is customary, the resuscitator is provided with a conventional positive pressure relief valve 51 and a conventional negative pressure relief valve 52, communicated with the main chamber 39 and set to open and close respectively at pressures deemed safe for the patients.
It will now be apparent that a resuscitator, for example, such as here shown, embodying an expansible chamber control unit in accordance with this invention, may be operated safely and eficiently for administering artificial respiration to small infants and animals, and when desired may be operated in the usual manner without depending upon the control afforded by the expansible chamber unit.
As shown in FIG. 9, a somewhat modified form of this invention provides for connection of the control unit 1 with the resuscitator in a different manner than shown in FIG. 1. In this modified form the hose line 14 is connected to a T-fitting 53 to which may be connected a mask not shown, or the endotracheal tube 43. The fitting 53 is provided with a valve 54 whereby the unit 1 may be connected in the flow circuit between the patient and the resuscitator or disconnected therefrom. In all respects this form is operable in the same manner as the form shown in FIGS. 1-8.
1. A resuscitator comprising a body having a gas chamber, a first passageway communicating with said gas chamber for admitting gas thereto and a second passageway extending from said chamber for establishing a gas flow circuit between said chamber and the lungs of a patient; gas operated means for controlling the flow of gas through said chamber, said gas operated means including a cylinder communicating with said chamber at one end and with atmosphere at the other end, and a piston reciprocable in said cylinder incident to above atmospheric and subatmospheric gas pressures in said chamber, and a valve member operably connected to said piston and mounted in said first passageway to provide alternate communication from the gas supply and the chamber, a discharge port providing communication between the gas chamber and the atmosphere, and a gas receiving bellows in said circuit in parallel to the lungs of said patient.
2. A resuscitator comprising a body having a gas chamber, 21 first passageway communicating with said gas chamber for admitting gas thereto and a second passageway extending from said chamber for establishing a gas fiow circuit between said chamber and the lungs of a patient; gas operated means for controlling the flow of gas through said chamber, said gas operated means including a cylinder communicating with said chamber at one end and with atmosphere at the other end, and a piston reciprocable in said cylinder incident to above atmospheric and subatmospheric gas pressures in said chamber, and a valve member operably connected to said piston and mounted in said first passageway to provide alternate communication from the gas supply and the chamber, a discharge port providing communication between the gas chamber and the atmosphere, and a secondary expandable chamber opening into said circuit in parallel to the lungs of said patient.
References Cited in the file of this patent UNITED STATES PATENTS