DE1227199B - Ventilator - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. CL:

A 61h

German: 30 k -13/01

Number:
File number:
Registration date:
Display day:

S 62699IX d / 30 k
April 22, 1959
October 20, 1966

The invention relates to a ventilator with a pulsator for supplying a breathing gas a patient. The task to be solved is to ensure a mode of operation in which the supply of Breathing gas remains constant for a certain period of time, regardless of any fluctuations in the flow resistance of the patient's respiratory tract or the lines belonging to the device, see above that the ventilation of the patient in this way maintains a constant, adjustable value.

In the known devices for ventilation, the breathing frequency, d. H. the number of inputs and Exhalations per minute as well as the amount of gas that is delivered by the device for each breath are set will. However, no consideration was given to the resistance in the patient's airways or taken in the lines leading to it, although this resistance may be variable can. If z. B. the resistance in the respiratory tract increases, this results in a higher compression of the gas in the device and in the line leading to the patient. In the event that the lung volume of the patient is relatively small, e.g. B. in a child, these ratios can increase insufficient gas supply to the patient's lungs. So it was done with the volume-controlled Ventilators switch from inhalation to exhalation when given a certain previously set amount of gas has been delivered by the device, regardless of the variable Pressure in the supply line. If these devices become blocked in the airways, will Although the previously set amount of oxygen is supplied by the device, it is not completely supplied to the lungs, because a larger proportion of the amount of gas supplied by the device remains in the supply lines.

In the ventilator according to the invention, the device automatically adapts as a function from flow resistance. The ventilator according to the invention is characterized in that that in the line leading from the pulsator to the patient a valve is provided which is of a pressure-sensitive member connected to this line is controllable in the direction that an in this line increased pressure an enlargement of the opening of this valve and thereby one This corresponds to an increase in the amount of air supplied to this line with each individual inhalation. It therefore, the amount of gas supplied to the patient per minute remains constant, and the ventilation of the Patient maintains a steady value, unab-ventilator

Applicant:

AGA Aktiebolag, Lindingö (Sweden)

Representative:

Dipl.-Ing. W. Mouths, patent attorney,

Frankfurt / M., Krögerstr. 5

Named as inventor:

Dag Johannisson,

Hakan Linderhohn, Lidingö (Sweden)

Claimed priority:

Sweden of April 28, 1958 (4109)

depending on possible pressure fluctuations in the line leading to it.
The object of the invention is in the drawing

«5 is shown for example. It shows

F i g. 1 shows an overview of a ventilator according to the invention,

F i g. 2 a modification of part of the device according to Fig. 1.

A patient 1 is to 3 breathing gas, z. B. Air or oxygen, also with the addition of an anesthetic gas, e.g. B. nitrous oxide, are supplied. The exhaled Gas is conveyed through a line 4, in which a slight negative pressure can be maintained, so that suction is exerted on the patient during exhalation. In lines 2 and 4 there is a diaphragm valve 5 with which one of the lines is blocked when the other is open.

For this purpose, the valve has a membrane 6, which either against a valve seat? or against a valve seat 8 can be applied. The membrane is also under the action of a spring 9 which causes a slight contact against the valve seat 7.

When the pressure in the line 2 behind the valve 5 is sufficiently large, the membrane 6 is from Seat 7 is lifted, and breathing gas is supplied to the patient 1, while the line 4 is at the same time remains locked. When the pressure in the named part of the line drops, the Diaphragm 6 is returned to the valve seat 7, and the patient can exhale through the line 4.

609 707/22

3 4

The rhythmic supply of breathing gas to the additional chamber with adjustable volume

Patient takes place in the case of FIG. 1 to be connected.

cführungform by means of a pulsator 10. This in order to- between the line 16 and the to the patient holds a membrane 11, through the two mechanically leading line 2 is a pre-coupled valve arrangement Valves 12 and 13 e.g. B. seen by means of a 5, by the action of which the amount of the dem Lever device 14 can be controlled so that patient supplied breathing gas in a one valve is closed while the other value remains set, even if the resistance is in is open. The valve 13 sits in a line 15, the respiratory tract or in the supply lines which is used to supply compressed gas to the device. should be changeable.

When the valve 13 is open, the pressurized gas is fed into a valve assembly 24 which includes a valve 25 Line 16 passed on and flows from here via a variable throttling effect. The valve 25 a check valve 17 and on an adjustable one has a pin 26 which is connected to a diaphragm 27 with a throttle screw 18 is bound by in a pressure chamber 19, through which the pin in different Abdie is located on one side of the membrane 11. stand can be adjusted from a valve seat. When the gas with one of the extent of the restriction 15 one side of the membrane borders a chamber 28 dependent speed through the non-return valve, which through a line 29 in the immediate Verventil flows past the throttle screw 18, the bond with the line 2 leading to the patient increases the pressure in the chamber 19, whereby the mem- is standing. The pressure within the chamber 28 is relevant here to close the valve 13 is always influenced by the pressure in the patient line will. At the same time, the valve 12, 20 opens the same. The membrane 27 is also under the and the line 16 is in contact with the environment in the action of a spring 30, which by an adjustment binding set. The pressure inside the chamber screw 31 to rest against the diaphragm 27

This gradually sinks 19, since that can be brought into this. On the other side of the chamber :. Gas through a line with a membrane is a second chamber 32, which on the one hand a second throttle screw 20 and a check 25 through a check valve 33, on the other hand through a check valve 21 in the line 16 is conveyed back a channel 34 of variable cross-section. If the pressure in the chamber 19 is related to one of the surroundings,
For setting the minimum amount of air, which under membrane 11 is brought back to its original position by a spring in normal circumstances through valve 25, the valve 25 flows through valve 13 again. If this is opened with an arrangement, the valve 12 is closed and the process described is repeated to limit its movement to the valve seat. It turns out to be a mistake. It can e.g. B., as in FIG. 1 shown, the periodic supply of pressurized gas to the line 16. Pin 26 may be formed with a flange 60, the

It is advantageous if the relationship between the movement of the pin towards the valve seat

Inhalation and exhalation times come to rest against an adjusting screw 61 independently of 35,

any fluctuations in the respiratory rate thereby limiting the movement of the valve pin

remains constant. Which is expressed in liters per minute.

Ventilation remains even with a variable At- The gas supplied through line 15 can be used as

ming frequency constant. The device can e.g. B. so the only breathing gas used for the patient set so that the exhalation time will be the Dop-40. It is also possible to save gas

pelte of the inhalation time. When breathing through to achieve that between valve 25 and

frequency then on twenty breaths per minute of the line 2 a jet nozzle 35 is provided through

is set, it follows that the air can be sucked in from the environment on every inhalation,

1 second and 2 seconds for each exhalation, so that a certain amount of money is saved through the leifallen. By keeping the ratio constant 45 device 15 gas supplied is brought about. In the

An air filter 36 and a valve are located between the inhalation and exhalation time

is enough that in the course of a longer period of time, 37 with adjustable passage opening. By means of this

e.g. one minute, always a constant part of valve 37 can provide the patient with

this period of time for the supply of breathing gas to the environment supplied air amount to a desired Patient is being exploited. In the example mentioned, a value of 50 can be set.

this resulted in such a way that the patient can use the adjusting screw 31 to

every minute for 20 seconds of breathing gas the spring 30 is adjusted to the diaphragm

was conducted. be that with every inhalation under ordinary

In the embodiment of the ratios shown in Fig. 1, a certain amount of air through the Invention, this constant ratio is thereby 55 valve 25 passes through it. If afterwards brought about that the two adjustment knobs 22 and one occasion the resistance z. B. in respiratory 23 to adjust the throttling screws 18 and because of or in the line 2 increases, the increases

20 provided with corresponding calibrations pressure in the line 2 and thus also in the Leisind, so that the desired constant ratio so tion 29 and in space 28. This pressure acts on is maintained long as the two buttons 60 the membrane 27, so that the valve pin 26 of are set to the same scale value. That he is removed from its seat and increased gas demand constant ratio between inhalation flow from the line 16 results. This and exhalation time can also be achieved as a result, increased can be just enough, because of the that the two throttling screws 18 and increased resistance brought about a reduction 20 are fixed. In this case, about 65% of the amount of breathing gas supplied to the patient can be used compensate for the desired variation in the respiratory rate.

can be achieved that the chamber 19 a changeable The device can also by changing the contact

has the same volume. You can z. B. with a pressure of the spring 30 against the membrane 27 by means of

the adjustment screw 31 can be adjusted so that either an incomplete compensation or a oversized compensation is achieved. In the latter case, there is an increased supply of breathing gas to the Patients with increased resistance.

When the diaphragm 27 responds in the manner discussed to the increase in pressure in the chamber 28, is Air is pressed from the chamber 32 into the environment through the check valve 33, after which the valve closes. When the pressure in line 29 is subsequently reduced, air will enter the chamber 32 sucked in at a speed determined by the throttling in the channel 34. This results in a delay in the return process, so that the valve 25 does not oscillate in time with the breaths will. A similar delay can also be achieved by switching on a check valve in the line 29 can be obtained through which the gas is quickly forced into the chamber 28 can. The check valve should have a bypass provided with a constriction, which is a gradual Lowering of the pressure in the chamber 28 allowed.

In the case of the FIG. 2, it is assumed, as above, that the line 2 serves to supply breathing gas to the patient. The breathing gas is sucked in through an opening 38 and flows through a valve 39 with adjustable flow opening and a check valve 40 to finally to be stored in a rubber bag 41, from where it is pressed into the line 2 can. The bag 41 can be compressed because it is surrounded by a chamber 42 through which a line 43 in communication with a source of pulsating pressure not shown in the drawing stands. The pressure can e.g. B. be generated in a known manner by pistons. That through the opening 38 supplied breathing gas can, as already mentioned, air or oxygen with the addition of anesthetic gas be. A second inlet opening 44, which acts as a valve, is also provided for the breathing gas is designed with an adjustable flow cross-section. This valve causes in the respiratory tract an increased supply of breathing gas to the bag 41 and thus to the line 2. To die-Sem For this purpose, the valve 44 is influenced by a membrane 45 which forms the wall of a chamber 46 forms. This is via a check valve 47 and a connection 48 with variable throttling j} i with the line 2 in connection. The valve 44 is at a standstill also under the influence of a spring 49, the pressure applied against the valve 44 by means of an adjusting screw 50 is adjustable.

The embodiment according to FIG. 2 works as follows: It is first assumed that the breathing resistance in the patient's respiratory tract, etc. is normal and inhalation stops is. The exhalation results from a pressure reduction in the chamber 42 and thereby effected expansion of the bag 41. The breathing gas is thereby through the check valve 40 as well sucked through the valve 39 at a speed dictated by the setting of the latter. The bag 41 is compressed by the subsequent increase in pressure in the chamber 42, see above that the breathing gas passes into the line 2 and on to the patient. One for some reason any increase in breathing resistance could lead to a greater proportion of the breathing gas is compressed in the line 2 and not supplied to the patient, whereby his ventilation becomes insufficient. This reduction in ventilation is used in the embodiment according to FIG. 2 thereby

ίο compensated that the resulting pressure increase the check valve 47 is raised in the line 2, so that a certain amount of gas enters the chamber 46. This leads to the lifting of the valve 44 by the membrane 45, so that with a subsequent decrease of the pressure in the chamber 42 and an expansion of the bag 41 caused thereby even larger amounts of gas can be sucked in by this, because breathing gas is not only through the opening 38, but also fed through valve 44

ao will. By means of the spring 49 and the adjusting screw 50, this additional amount of gas can be brought about an exact compensation, an undercompensation or an overcompensation with respect to the on Reduced ventilation due to the respiratory tract resistance. As with the arrangement according to FIG. 1, the check valve 47 and the connection 48 are used for delay of the return process in the desired manner.

In the case of the in FIG. The embodiment shown in FIG. 2 does not require the bag 41 in FIG Way to arrange. It would be B. also possible to connect the bag 41 to the line 43.

Claims (3)

Patent claims: 1. Ventilator with a pulsator for delivery of breathing gas, characterized in that in the from the pulsator (10) to the patient (1) leading line (16, 2) a valve (25, 44) with variable throttling effect is provided, that of a pressure-sensitive member (27, 45) connected to this line in the direction it is controllable that an increased pressure in this line results in an enlargement of the opening this valve and thereby an increase in the amount of air supplied to this line corresponds to each individual inhalation. 2. Ventilator according to claim 1, characterized in that the pressure-sensitive Organ comprises a membrane (27, 45), on one side (28, 46) of which there is the same pressure as on the line. 3. Ventilator according to claim 2, characterized in that the other side of the membrane (27) delimits a chamber (32) which is in communication with the environment via a check valve (33) and a channel (34) with adjustable flow resistance. Considered publications: U.S. Patent No. 2,774,352,2,737,178;
Medizinal Markt, 1956, No. 8, pp. 284 to 289;
Advertising leaflet P 564, 5th edition, February 1958, from the Drägerwerk Lübeck company. 1 sheet of drawings 609 707/22 10.66 © Bundesdruckerei Berlin