DD211221A3 - ELECTRONIC CONTROL FOR VENTILATION DEVICES - Google Patents

Abstract

The invention relates to an electronic control for ventilators, with integrated circuits for logic functions many types of ventilation and a timing system for the inspiratory and expiratory phase, the signals of an optical respiratory rate display are supplied. The aim of this control is to achieve maximum variability of the ventilation characteristic while at the same time realizing sensible limit value formation. It is intended to have several tap possibilities within a respiratory or ventilation period, from which peripheral modules for controlling the volume or pressure curve in the ventilation process can also be controlled, as well as control modules for limiting value formation. This is achieved according to the invention with an electronic control in which the timing system is constructed as a time sequencer and provided with serial 4-bit shift registers, which are connected by meaningful Signalverknutpfung with switches, flip-flops, other slide registers and solenoid valves with a digital respiratory rate computer.

Description

Electronic control for ventilators <

Field of application of the invention:

The invention relates to an electronic control for ventilators with integrated circuits for logic functions of many types of ventilation and a timing system for the inspiratory phase and expiratory phase, the signals of which are supplied to an optical respiration rate display.

Characteristic of the known technical solutions i

In new ventilators, the types of beat are controllable by unified therapy systems, such as intermittent positive pressure ventilation (IPPV), also optionally assisted and associated with end expiratory positive pressure (PEEP), continuous positive airway pressure functions during all phases of spontaneous breathing (GPAP), intermittent forced ventilation (IMV) , this also optionally assisted or rate-controlled. In addition, other states (HPIIP./ ZEEP / NEEP / Sigh Puncture / Plow Puncture, Accelerating, Decelerating, and Constant) are controllable in the summary of these punctures, allowing for variable limit selection and variable display of selected parameters.

Characteristic of the many known ventilators is that their working cycle has an inhalation phase and an exhalation phase. These are controlled either in the print cycle or in the time cycle * A module selection can be provided for this purpose *

Both phases are set in time control by separate time mechanisms, as a result of which a corresponding respiratory time ratio and a corresponding frequency develop. But it can also be the frequency and the Atemzeitverhältnis be given ^ so that then appropriate inspiration and expiration times abut (DE-OS 2,745 3o9) "The fixed division of the working cycle or the respiratory period in inspiratory phase and expiratory phase, however, narrows the optimal design of the ventilation characteristic in that within this division no Abgriffsmöglichkeiten for control signals for the actuation of actuators are available and intervention only within the phases are made possible by expensive additional mechanisms within the phases. The lack of intervention does not allow anything targeted and on all sides the volume or "pressure curve of the ventilation curve while maintaining the same mechanisms of action control technology without disadvantages to vary * So, for example, the design of a break between the conventional inspiratory and expiratory phase can be realized only by an additional delay circuit _s then either the effective inspiratory or expiratory time 'shortened and thus changed the starting or reference conditions for the choice of break by the doctors.

Also, the implementation of the IMV requires a separate time mechanism, but may be incorporated between the periods of respiration to provide a period of spontaneous breathing. The practice of frequency reduction is disadvantageous in that the transition from IPPV to IMV and vice versa is only relatively coarse Gradation is possible (DE-OS 2,746,924)

 On the other hand, an end-expiratory pressure (PEEP) is generated

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you take u · a. a mechaniach working device to complete, z. B. a PEEP valve that closes the exhalation within the selected expiratory phase after reaching the preselected pressure. The known devices, however, undesirably increase the aspiration resistance and are very prone to vibration and noise (Anaesthesia, 1977, Vol. 32 Ni, 2, pp. 138-147). ^ '

The unwanted disadvantages to avoid an automatic ventilator means of a control unit, which performs electronic controls and calculations as well as a pneumatic control and regulation for a number of the above types of ventilation (DB-OS 2,745,528). This ventilator also introduces a respiratory system that delivers pressurized breathing gas to a patient, with shifters responsive to control signals to control patient gas flow for inspiration and expiration. In this case, the electronic control task is to allow selection and adjustment of various parameters, such as pressure, respiratory rate, volume, etc. The pneumatic section of the control unit, however, performs various functions and of these in particular the pressure control of the inflowing gas and its control in the patient group.

Controlling such vital respiratory parameters as deep breathing, respiratory pause, positive and expiratory pressure (PEEP), continuous positive airway pressure (CPAP), and auxiliary actions requires, in addition to a variety of electronic and pneumatic building blocks and interconnections, complex electronic units that are a logical consequence of closing and breathing Opening solenoid slides cause. Finally, the processes for automatically controlled inhalation are carried out via so-called comparators whose return to a certain switching state on the one hand causes the numerical representation of calculated breaths per minute, on the other hand initiates the respective new conversion period and a new conversion cycle. Bs is certainly to be assumed that 'the relatively complex, but technically controllable system solution the

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Also, with a program control and a timing valve circuit, ventilation of any kind is suitable only for the purpose of controlling the many types of ventilation and other feasible conditions in a satisfactory quality, but their circuitry, and in particular the sequential circuits constructed by means of multiple solenoid shifters, is complicated for comparison and timing Use of disadvantageous additional mechanisms feasible (DE-OS 29 Io o94).

Object of the invention:

The aim of the invention is the elimination of the indicated disadvantages and the avoidance of a complex circuit structure. Its purpose is in particular to achieve the highest possible variability of the respiration characteristic without complex additional mechanisms while at the same time realizing useful limit value formations for life-threatening parameter combinations and optical display of selected parameters.

Explanation of the essence of the invention!

The invention has as its object to develop a constructed from integrated circuits BeatmungsgerätesteueruMg, the ventilation period has within the respiratory or _e Abgriffsmöglichkeiten several of which -bzw of peripheral modules for controlling the volume. Pressure curve in the ventilation process can be controlled as well as control modules for limiting value formation and visual display. According to the invention the object is achieved by an electronic control in which the time control system is constructed as a time sequence control and provided with four serial 4-bit shift registers, once via two 4-pole switches and two similar 3-bit shift registers with three flip-flops and these subordinate solenoid valves and the other with a third similar 3-bit shift register are signal-linked, via a flip-flop, a temporal sequence of computer inputs controlling 4-bit Schieberegisier, another flip-flop and two to determine the Atemperiodendauer certain 4-bit shift register is connected to a digital respiratory rate calculator.

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The advantageous embodiment of the invention is that the four serial 4-bit shift registers each consist of a 4-lbit up / down counter and a binary / 1 of 16 decoder ", each with a 16-pin switch and a second -poligen switch are connected, of which two shift registers are additionally guided via a frequency divider and / or a 3-pole switch, that two of the 16-pole switch with the one 4-pole switch and two of these 16-pole switch with the other 4-pole switch in connection and that the one 4-pole switch signal-linked 3-bit shift register on the one hand directly and on the other hand connected via an 8-pin switch to the second 3-bit shift register.

Bine expedient embodiment is still in that responsible for the last respiratory phase period l6-pole switch ·. output s it ig linked to the signal line of an assistant and this can be switched directly by means of an OR gate.

With this ventilator control the set goal is achieved and solved the task according to the invention. By providing the signals and the preselection of Steueraai'ianten a variety of multi-phase conditions and volume or Druckbeatmungsarten can be produced, so that the patient is better ventilated. Further advantages of the invention, as well as further details and features, will become apparent from the description of the following embodiment.

Embodiment:

An embodiment of the invention will be described below with reference to the figures of the accompanying drawings.

Show it

Pig. 1: a detail view of a ventilator front panel, Pig. 2: a graphical representation of the multiple phase relationships of some beat options,

Pig. FIG. 3 shows a logical combination of integrated microcircuits of an electronic controller of a ventilator as the first part of the overall system, FIG.

'Flg.'s4 j a second part of the electronic control subsequent to the first part of Fig. 3 in also logically linked representation,

Pig «5? a first part of one with the electronic control to Pig. 3 and 4 logically linked digital aterafacial computer and:

Pig. FIG. 6r shows a second part of the respiratory-frequency computer which adjoins the first part according to FIG. 5 in likewise logically linked representation.

The ventilator according to the invention is provided with an electronic controller 1 and a digital respiratory frequency calculator 2, both of which are constructed from integrated microcircuits and appropriately linked together. The controller 1 and the respiratory frequency computer 2 form a compact unit which is provided with externally operable switching and adjusting means to allow the selection of the types of ventilation and other conditions. Logically connected to the micro-circuits controls are at the in Pig. I front panel 3 shown arranged, which also has a digital frequency display 4 and a certain for the airway pressure gauge 5.

With the help of the microcircuits according to the invention, the compact unit has several Abgriffmöglichkeiten within the respiratory or respiratory period, from which now peripheral modules for controlling the volume or pressure curve in the ventilation process can be controlled as well as control modules for limiting value for life-threatening parameter combinations and visual display. The ventilator thus realizes types of ventilation with optimal design options for the ventilation characteristic and a subdivision of the respiratory or "ventilation period" into periods with variable ratios. The signals provided via the circuits can

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In accordance with the selected control variant and in connection with flow and directional valves different multi-phase ratios produce, some of which in Pig. 2 are shown abstracted.

The feasibility is achieved with the electronic control according to FIGS. 3 and 4, which is a time sequence control consisting of 4-bit shift registers 6, 7, 8 and 9. These four independently adjustable shift registers each consist of a 4-bit up / down counter and a binary / 1 of 16 decoder. • In addition, they are each connected to a 16-pin switch designated by the reference numbers lo, 11, 12 and 13 characterized once by two 4-pole switches 14, 15 and two similar 3-bit shift registers 16, 17 with three flip-flops * 18, 19,2o and these downstream solenoid valves 21, 22, 23 and the other with a third similar 3-bit shift register 24 are signal-linked. Furthermore, the first two 3-bit shift registers 16, 17 on the one hand directly and on the other hand via an 8-pole switch 25 together and the 4-bit shift registers 6 to 9 via a 2-pole switch 26 connected to a square wave generator 27, from. which the shift registers 8, 9 are additionally guided via a frequency divider 28 with a ratio of 1: 8 and / or a 3-pole switch 29.

The square-wave generator 27 is connected to the clock inputs C of the 4-bit shift registers 6 to 9, which are signal-linked via the outputs of the 16-pole switches Io to 13 with the 3-bit shift register 24, the output side a connection to the time signal of the breathing phase times t ^ to t, to the activation se ingangs 1 of the 4-bit shift registers 6 to 9 has, which the solenoid valves 21 bie 23 turn on the rhythm of the signalized clock frequency fm via the switches 14, 15 and the flip-flops 18 to 2o ,

The one for the Atemphasenzei't t, responsible l6-pole switch 13 is output side linked to the signal line of an assistant 3o, which is directly connectable by means of an OR gate 31. And finally, the solenoid valves connected to the first flip-flop 18 and the second flip-flop 19 are

on the gas side via adjustable flow throttles 32, 33 connected in parallel.

The one in the Pig. 5 and 6 " illustrated digital Atemfrequenz ~ computer 2 consists of a Kechnerbaustein 34 with display unit 35, one of the temporal sequence of computer inputs controlling 4-bit shift register 36 and two other., For determining the Atemperiodendauer particular 4-bit shift registers 37, 38th , two used to trigger the control and counting operations flip-flops 39, 40 and ten for the logical input of digits and characters in the Hechnererbaustein 34 specific AND gates 41 to 5o.

As can be seen from the representation of the respiratory frequency computer, the flip-flop 39 which is signal-linked to the electronic control is connected to the clock input of the 4-bit shift register 36 which is connected to the computing frequency f _R. The outputs of this 4-bit shift register 36, except for an output associated with the R input of the flip-flop 39 and the enable input of the 4-bit view register 36, connect to and through the MD gates 41 to 5o Computer module 34, wherein from the outputs of this 4-bit shift register 36, a still additionally the S input of the second flip-flop 4o and another additionally the R input of the same flip-flop 4o and the activation inputs of the two the Atemperiodendauer detecting 4-bit shift register 37, 38 connected. Finally, there is the one at the clock input with pulses.

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put 4 ~ bit shift register 38 with its one output led on the one hand to its activation input, on the other hand connected to the clock input of the other 4-bit shift register 37, währe'nd the other terminals of the outputs of these two 4-bit shift registers 37, 38 via the AND gates 44 to 49 and are directly signal-linked to the computer module 34, which is still in communication with a signal generator and with the display unit 35.

Starting from the compact unit presented here and its logical wiring, the respiratory phase times t- ,, t _? , do not. an Atemperiode T of Fig. 2 by means of the l6-pole switches Io to 13 set and the types of ventilation via the switch

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14 »15» 25 »26, 29 and the frequency divider 28 and the square-wave generator 27 realized. When the ventilator is started up and the operating voltage applied, the clock pulses fm are applied to the clock inputs of the 4-bit shift registers. At the same time, the 3-mi shift register automatically supplies Η-level at output 1, enabling 4-bit shift register 6 to be enabled. The first following clock sets its output A i to H and sets via the switch 14 the flip-flop 18. Thus, the solenoid valve 21 is turned on and the inspiratory time t-, begins »

In the rhythm of the clock frequency fm is now switched to the next output. If the output signal reaches the output occupied by the switch Io, both the flip-flop 18 is reset and the 4-bit shift register 7 is activated via the 3-bit shift register 24. This has the consequence that the solenoid valve 21 is turned off and the flip-flop 19, the solenoid valve 22 is turned on, whereby the inspiratory time t, is completed and the inspiratory time t _? starts to run. The further sequence in the 4-bit shift registers 7 to 9 takes place analogously to the 4-bit shift register 6.

With the activation of the 4-bit shift register 8, the flip-flop 2o is set via the 4-pole switch 15 and the solenoid valve 23 is turned on. From this time, the expiration t begins to run until the solenoid valve 23 is closed again at the end of its term. It now follows the Exspirationsze.it t ,, during which the solenoid valves 21 to 23 are closed. At the end of the expiration time t..., The 4-bit shift register 6 is started again via the 3-bit shift register 24.

Earlier it has already been stated that the solenoid valves 21 and 22 are connected in parallel with the gas through the adjustable flow restrictors 32, 33, so that depending on the throttle position between accelerating and decelerating flow during the inhalation'-varied: can be. If, on the other hand, the flow restrictor 33 is completely closed, a pressure course with an endinspiration plateau (PEIP) occurs during the inspiratory time, tp.

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When the 4-pole switch 1/4 is switched over, the flip-flop 18 is set by the 4-bit shift register 6 and is reset by the 4-bit shift register 7 only at the end of the inspiration time t ". As a result, the flip-flop 19 is not used, and only the solenoid valve 21 is turned on during the entire inspiratory time t-, and tp '. As a result, a constant flow of breathing gas sets in «

In a further position of the 4-pole switch 14, the flip-flops 18, 19 are set at the same time by the 4-bit shift register 6 at the beginning of the inspiratory time t and only at the end of the inspiratory time t _? reset by the 4-bit shift register 7 again. That is, the two solenoid valves 21, 22 are opened during the entire inspiration time t ^ and t ~. Recessed breaths are achieved by the gas-side parallel connection, the ratio of which is set to normal breaths at the 8-pole switch 25 and implemented in conjunction with the 3-bit shift registers 16, 17.

The respiratory gas flow can also be influenced in the expiration times t.sup.-1 and t.sup. +. If, for example, the expiration time t, compared to the expiration time t, is chosen to be small, an endexspiratorisch.es plateau (PEEP).

To realize an intermittent forced ventilation (IMV), the switches 15 and 29 are switched so that at the beginning of the expiration time t ~ through the 4-bit shift register 8, the flip-flops 18, 19 via their static inputs S together with the flip-flop 2o, so at the same time, be set. The three flip-flops 18 to 2o are reset only at the end of the expiration time t, by the 4-bit shift register 9 ", namely when the switch position set at the switch 13 has been reached. During the entire expiration t ^ and t. the solenoid valves 21 to 23 are in the open position, allowing a spontaneous Abatmen from the large amount of gas offered. To extend the expiration times t "and t. is switched with the switch 29 of the frequency divider, which reduces the clock frequency f ^ for the 4-bit shift registers 8, 9.

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It thus becomes a time extension of the total expiratory times t_ and t. reached eightfold.

In a further switching stage of the switch 15, an operating condition can be created which makes it possible to switch to inspiration immediately upon inhalation attempt and to realize assisted ventilation. The operating condition of the electronic control 1 is provided by the switch 15 turning on the assistor 3o, the OR gate 31 providing the 4-bit shift register 6 at any time during the entire expiration time t ~ and t. starts.

As set out above, this electronic control, which is constructed as a time sequence control, is connected to the respiratory frequency computer 2, which as already explained essentially consists of the computer module 34 with display unit 35, the 4-bit shift register 36 which controls the chronological sequence of the computer inputs. Bit shift registers 37, 38 for determining the Atemperiodendauer, the flip-flops 39, 4o to trigger the control or counting operations and the AND gates 41 to 5o for the logical input of digits and characters. Their links then also provide a connection of the digital outputs D 1 to D via the AND gates 41 to 5o with the number and operation signal inputs of the computer module 34, the respiratory rate f «by the division of 6o seconds with the sum of the breathing phase times t - until t. determined.

At the beginning of the tnspirationszeit t, the flip-flop 39 is set by a start pulse of the controller 1, which in turn turns on the 4-bit shift register. At the clock frequency f ;, the outputs AO to A 15 are now set to Η level , This process has the consequence that at Η level on output A 1 'via the AND gate 41, the second input to the output D 6 of the computer module 34 is a "six" is entered into the computer module 34. At Η level on output A 3 of the 4-bit shift register 36 via the AND gate 42, the input of the first "zero" and also a second "zero" at Η level on output A 5. In continuation of Clock of the, computing frequency f _K is then the operation signal with A 7 signal

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"Divide" input, then followed by A 9 and A 11 signal, the two-digit measured value of the respiratory phase times t to t . This measured value is determined by operating as a counter 4-bit shift registers 37, 38 by the applied to the clock input G of the 4-bit shift register 38 pulses t " to stop the 4-bit shift register 38 by O signal of Flip-flops 4o are counted. The flip-flop 4o is set at Η-level at the output A 9 of the 4-bit shift register 36, since at this time with the reading of the measured value of the 4-bit shift register 38 (tens) is started. The output A 11 of the shift register .36 triggers the input of the values from the 4-bit shift register 37 (one).

After completion of the value input and now applied H level at the output A 13 of the 4-Mt shift register 36, the two 4-bit shift registers 37, 38 and the flip-flop 4o are reset, whereby a new Zählrhythmus begins. In addition, with the reset, the operation flag "is equal to" via the AND gate 5o entered into the computer module 34. After this input and the calculated respiratory rate f. the display is made on the display unit 35

Finally, if the Η level at the output A 14 of the 4-bit shift register 36 is present, this and the flip-flop 39 via the! Input or R input of their circuits are reset. Thus, the respiratory rate calculator 2 is ready to record again for the next of the electronic control 1 fed start pulse.

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Claims (2)

ürfindungsanspruch: 1. Jlektronip.che control for Beatrnüngsgeräte, with integrated circuits for logic punctures of many types of ventilation and a timing system for the inspiratory and expiratory phase, the signals of an optical respiration rate display are fed, characterized in that the timing system constructed as a time sequence control and four serial 4-bit shift registers (6 to 9), which once via two 4-pole switches (14, 15) and two similar 3-bit shift registers (16, 17) with three flip-flops (18 to 2o) and These downstream solenoid valves (21 to 23) and on the other hand with a third similar 3-bit shift register (24) are signal-linked, via a flip-flop (39), a time sequence of the Hechner inputs controlling 4-bit shift register (36 ), Another two flip-flops (Ao) and two 4-bit shift registers (37 »38) intended for determining the duration of the duration of the respiratory period with a digital respiration rate computer (2) is. ' 2. Electronic control for ventilators according to item 1, characterized in that the 4-bit shift registers (6 to 9), each consisting of a 4-bit up / down counter and a bi-level . ' :.: ' när / 1 consist of 16 decoders, each with a l6-pole switch (Io to 13) and a 2-pole switch (26) are connected, of which the shift registers (8, 9) in addition to a Frequency divider (28) and / or a 3-pole switch (29) are guided, that the two switches (lo, 11) with the one 4-pole switch (14) and the other two switches (12, 13) with the other 4-pole switch (15) are in communication and that the switch (14) signal-connected 3-bit shift register (16) on the one hand directly and on the other hand via an 8-pin switch (25) to the, 3-bit shift register ( 17) is connected. , . Electronic control for ventilator according to item 2, characterized in that the 16-pole switch (13) on the output side connected to the signal line of an assiator (3o) and this can be switched directly by means of an OR gate (31). For this-i-Seitenileidinungen .- ι -i; ^; '.y;-' .. ..;.; -,; '.-. .ι,: