JPH0321259A - Driving device for blood pump - Google Patents

Abstract

PURPOSE:To inform abnormality only when abnormality of the pressure pulse of a driving device is surely caused by providing a pressure check timing time extending means for extending the time of pressure check timing when a pressure diagnosis means detects a pressure abnormality. CONSTITUTION:A blood pump driving device 10 comprises pressure pulse generating devices 11, 12 for right heat and left heart, an electronic control unit(ECU) 13 for controlling the pressure pulse generating devices 11, 12, a power supply 14, an operating switch 21 for setting a preset value for control of the blood pump driving device 10, a buzzer 19 for informing abnormality, a buzzer driving circuit 20, a pressure detector 15 for detecting the pressure output by the pressure pulse generating device 11 and a pressure detector 16 for detecting the pressure output by a pressure pulse generating device 12. Only when the pressure is surely abnormal, abnormality is informed, so that malfunction is reduced, reliability is increased, pressure abnormality can be surely informed so as to improve patient's and doctor's confidence in the device. Accordingly, they can do medical treatment with a sense of security.

Description

[Detailed description of the invention]

[Object of the invention] (Field of industrial application) The present invention is directed to a pressure-driven complete artificial heart, an auxiliary artificial heart,
The present invention relates to a drive device for a blood pump such as a balloon pump that is driven by pressure pulses. (Prior Art) Blood pumps assist and support the function of the heart of patients with weakened circulatory systems. Therefore, if the blood pump drive device stops functioning, it will have an adverse effect on the patient. In a complete artificial heart, the heart has no function at all, and in an auxiliary artificial heart or a balloon pump, the patient's weakened heart is suddenly put under stress. Therefore, blood pumps and drives must reduce the frequency of failure. For this reason, in case the external power supply is cut off in case of a failure of the drive device, a device with a built-in battery and a pressure tank (Japanese Patent Application Laid-open No. 136352/1983), and multiple pressure sensors to monitor the pressure waveform are installed. The device (Japanese Patent Application Laid-Open No. 60-207668) is equipped with two pressure generating devices, and when one pressure generating device fails, the other pressure generating device is activated.
A device that can be switched to a single pressure generator (Unexamined Japanese Patent Publication No. 5
8-169463, Japanese Patent Application Laid-Open No. 62-249655), etc. have been proposed. Conventionally, the method for detecting a failure in the drive device is to detect the pressure output according to the set pressure check timing, compare the detected pressure with the set pressure, and check whether the detected pressure is higher than the set pressure. An abnormal deviation is considered a failure. For example, in Japanese Unexamined Patent Publication No. 62-249655, the cycle of pressure pulses and the pressure level are checked. (Problems to be Solved by the Invention) It is necessary to make the period and duty ratio of the pressure pulse variable due to the relationship with the living body. Therefore, when diagnosing pressure pulse abnormalities, it is necessary to determine the pressure detection check timing in consideration of the settable minimum cycle and minimum and maximum duty ratios. The pressure pulses output by the drive device alternately output positive pressure and negative pressure, so the rise of pressure may be slow after switching from negative pressure to control pressure, or the rise of pressure may be slow after switching from positive pressure to negative pressure. A slowdown in the decline occurs. Because of this process, it takes time for the pressure to reach the set pressure after changing the pressure. This time varies depending on the pressure value before pressure switching. For example, when switching from negative pressure to positive pressure, if the negative pressure value before switching is large, it will take a long time for the pressure to stabilize to the positive pressure set value after switching, and if the negative pressure value before switching is small, After switching, the pressure immediately rises to the positive pressure setpoint. For this reason, the pressure may not be stable at the time of pressure detection check due to the bluntness of the pressure waveform, and the detected pressure may deviate from the set pressure. In some cases, even if the drive device is normal, it may be determined to be abnormal. This may lead to distrust on the part of the doctor and patient towards the device, and may result in the doctor not operating the device properly.

[There is also a risk of inducing stress.] Therefore, it is an object of the present invention to provide an abnormality notification only when an abnormality in the pressure pulse of the drive device definitely occurs. [Structure of the invention]

(Means for Solving the Problems) The technical means used in the present invention to solve the above problems are a pressure pulse generator that generates pressure pulses, and a pressure detection means that detects the pressure generated by the pressure pulse generator. , a pressure diagnosis means for diagnosing whether the output value of the pressure detection means is normal according to pressure check timing, and a pressure for extending the time of the pressure check timing when the pressure diagnosis means detects a pressure abnormality. The blood pump drive device is equipped with a change timing extension means. (Operation) According to the above technical means, when the pressure generated by the pressure pulse generator is diagnosed as abnormal in pressure check tying, the pressure check tying time is extended. Therefore, the next time pressure is diagnosed,
This is different from the previous pressure check tying. For example, the rise of a pressure pulse. Even if it is diagnosed that the pressure is abnormal during the first pressure diagnosis due to the fall, the abnormality diagnosis will be performed again when the pressure is stabilized due to the extended tie ring. Therefore, an abnormality is diagnosed only when the pressure is definitely abnormal. Furthermore, if a pulse time extension means is provided for extending the period or ON time of the pressure pulse of the pressure pulse generator when the pressure diagnosis means detects a pressure abnormality, the pressure can be surely stabilized. You can wait and re-diagnose. This is effective in the case where the extended pressure check tie extends beyond the positive pressure time or negative pressure time in the method described above. (Example) Hereinafter, an example of the present invention will be described with reference to the drawings. Referring to FIG. 1, the blood pump driving device 10 includes an electronic control unit (ECU) that controls the pressure pulse generator 11 for the right heart, the pressure pulse generator 12 for the left heart, and the pressure pulse generators W11 and 12. 1 3, power supply 14 for ECUI 3, operation SW 21 for setting control settings for blood pump drive unit W10, buzzer 1 for notifying an abnormality
9. Buzzer drive circuit 20, pressure detector 15 that detects the pressure output from pressure pulse generator Wj1, and pressure detector 16 that detects the pressure output from pressure caballus generator 2.
Equipped with The two pressure pulse generators each have a positive pressure source 11a. which is a combiner that generates positive pressure. 1.2a
, a 1lb negative pressure source that is a vacuum pump that generates negative pressure.
, 12b and a solenoid valve 11C for alternately switching between positive pressure and negative pressure. having 1ld, 12C and 12d, -
Although not shown, the ECU 13 controls the positive pressure sources, negative pressure sources, and solenoid valves in the two pressure pulse generators 11 and 12 according to information such as the blood pressure and electrocardiogram of the living body to which the blood pump is attached. It synchronizes the timing of the pulsations and pressure pulses, and adjusts the pressure depending on the living body. The output of the pressure pulse generator 11 for the right heart is sent to the blood pump through the piping 17 for the right heart. The output of the left heart pressure pulse generator W12 is sent to the blood pump through the left heart line 18. The structure of this blood pump drive device is almost the same as the artificial heart drive device disclosed in Japanese Patent Application Laid-Open No. 169480/1982, so please refer to that publication for information on the generation and method of pressure pulses, etc. The pipe 17 is connected to an artificial heart pump 22 which is a blood pump. An artificial heart pump 22 is cannulated into the right atrium and pulmonary artery. When the pressure in line 17 increases, the artificial heart pump pumps blood into the pulmonary artery, and when the pressure in line 17 decreases, the artificial heart pump draws blood from the right atrium. Similarly, the pipe 18 is connected to an artificial heart pump 23 which is a blood pump. An artificial heart pump 23 is connected to the left atrium and the aorta through a cannula. When the pressure inside the pipe 18 increases, the artificial heart pump pushes blood into the aorta,
Furthermore, when the pressure within the pipe 18 becomes low, the artificial heart pump sucks blood from the left atrium. ECU13 is a one-chip microcomputer,
It operates according to the flowcharts shown in FIGS. 2 to 6. FIG. 2 shows the main routine of the microcomputer. When the microcomputer starts, the internal memory and human output terminals are first initialized (Stesub 30). Next, the signal input routine (step 31),
Waveform display routine (step 32), abnormality diagnosis routine (step 33). The five routines of the left heart and right heart beat control routines (steps 34.a, 34b) are repeated. The signal input routine is for inputting pressure signals from the pressure detectors 15, 16, etc. Further, the pressure setting value and pressure check timing are also set here using the operation SW21. The output value of pressure pulse generator [Nano pressure detector] 5 on the left heart auxiliary side is LP
, the output value of the pressure detector 16 of the pressure pulse generator on the right heart auxiliary side is RP. In addition, the left heart positive pressure setting value is LPP
S. Right heart positive pressure setting value is RPPS, left heart negative pressure setting value is LN.
PS, the right heart negative pressure set value is RNPS. The left heart negative pressure pressure check timing is TLSET (time from negative pressure application), and the right heart negative pressure pressure check timing is TRSET.
, The pressure check timing for left heart positive pressure is TLONSET <s
(time after pressure application), and the time to check the right heart positive pressure is TRONSET. In the waveform display routine, processing is performed to display the waveform and each data on a display (not shown) based on each measured value. The abnormality diagnosis routine diagnoses an abnormality in the pressure pulse generator based on the measured blood flow value and pressure value, and performs processing to prevent the buzzer from sounding if an abnormality is detected. In the left heart and right heart beat control routines, a solenoid valve in the pressure pulse generator is driven based on the measured pressure value and the like to switch the pressure. The microcomputer of this embodiment has a timer interrupt, and the timer interrupt routine shown in FIG. 3 is executed every predetermined time. When the timer interrupt routine is executed, the timer TL indicating the pressure check timing is
NC, TRNC. TLPC. TRPC, period timer TL, TR, on-time timer TLO
N. TRON is each decremented by one. In addition, in the pulsation control routine to be described later, timers TLNC and T indicating the pressure check timing during negative pressure are used.
RNC is set at the start of negative pressure application, and each other timer TLPC. TRPC, TL, TR.
TLON and TRON are set at the start of positive pressure application. The contents of each flag used from FIG. 3 onwards are shown in FIG. 9, so please refer to this at the same time. The details of the abnormality diagnosis routine will now be explained with reference to FIG. 4.5. When the abnormality diagnosis routine is executed, first, the pressure value supplied to the blood pump is diagnosed (step 38). Here, left heart negative pressure diagnosis, right heart negative pressure diagnosis, left heart positive pressure diagnosis, and right heart positive pressure diagnosis are executed in this order. Left heart negative pressure diagnosis is performed when timer TLNG reaches O. When timer T LNC reaches O, left heart negative pressure setting value LN
The difference between PS and the pressure value LAPO on the left side of the heart at that time is 20+n+
If it is within ++IIg, it is normal. 2 Q+y+mll
If it exceeds g, it is judged as abnormal. Note that this value of 20 mdg is set in consideration of fluctuations in the apparatus. After this,
If the pressure is normal, the left heart negative pressure continuous abnormality counter ABL
NC is set to "5", and if abnormal, the corresponding counter ABLNC
Decrement. Therefore, if the left heart shadow overwhelm becomes abnormal five times in a row, the continuous abnormality counter ABLNC will be “O”.
''. Right heart negative pressure diagnosis, left heart positive pressure diagnosis, and right heart positive pressure diagnosis are also performed in the same way. Right heart negative pressure diagnosis is performed using timer T.
Performed when RNC becomes 0, right heart negative pressure set value RNPS
The difference in pressure value RAPO on the right side of the heart at that time is 20 mn+ll
If it is within g, it is normal. If it exceeds 20+usllg, it is judged as abnormal. Then, if the pressure is normal, the continuous abnormality counter ABRNC for right heart negative pressure is set to "51", and if it is abnormal, the counter ABRNC is decremented. Left heart positive pressure diagnosis is performed when the timer T LPG reaches 0. , If the difference between the left heart positive pressure setting value LPPS and the pressure value LAPO on the right heart side at that time is within 20mmllg, it is considered normal;
If it exceeds llg, it is judged as abnormal. If the pressure is normal, the left heart positive pressure continuous abnormality counter ABLPC is set to “5”.
”, and if abnormal, the counter ABLPC is decremented. Right heart positive pressure diagnosis is performed when the timer TRPC reaches O, and the difference between the right heart positive pressure set value RPPS and the right heart side pressure value RAP at that time is determined. If the pressure is within 2Qmmllg, it is determined to be normal, and if it exceeds 20mmllg, it is determined to be abnormal.If the pressure is normal, the right heart positive pressure continuous abnormality counter ABRPC is set to "5", and if it is abnormal, the counter AB
Decrement RPC. At each check time, each memory T LNCSET,
TRNCSET, TLPCSET, TRPCSET
This can be changed by changing the value set in . The check timing is determined based on the minimum settable cycle of pressure pulses. For example, if the settable positive pressure application time is 100 ms, the check period is 10 ms after switching from negative pressure to positive pressure.
It is preferable to set it to an arbitrary time within 0 ms. In this embodiment, as shown in FIG. 9, the positive pressure check timing is 100ms from the start of positive pressure application. The negative pressure check timing is 100 ms after the start of negative pressure application. Therefore, here, the memories T LNCSET, TRNCSE
T, TLPCSET, TRPCSET all 100
Set to ms. After each pressure diagnosis is completed, an abnormality diagnosis of the device is performed. If the abnormal flag ABF is 0, the first abnormality diagnosis is performed, and if the abnormal flag ABF is 1, the second abnormality diagnosis is performed.
Diagnose abnormalities. Note that the abnormal flag ABF is set to 0 at the time of initialization. Therefore, if the device has been normal until now, the abnormal flag A
BF is 0. In the first abnormality diagnosis, each continuous abnormality counter ABLNC, ABRNC, ABLPC. ABR
Abnormal flag A when one of the PCs becomes 0 or less
Set BF to 1. Each continuous abnormality counter ABLNC.
If ABRNC, ABLPC, and ABRPC are all less than 0, perform an operation to silence the buzzer. When the abnormality flag ABF is set to 1 in the first abnormality diagnosis, a second abnormality diagnosis is performed in the next abnormality diagnosis routine. In the second abnormality diagnosis, each continuous abnormality counter ABLNC, AB
When one of RNC, ABLPC, and ABRPC becomes -1 or less, a process is performed to sound a buzzer. If the continuous abnormality counters ABLNC, ABRNC, ABLPC, and ABRPC are all 0 or more, the abnormality flag ABF is set to O. As described above, if any one of the left heart negative pressure, right heart negative pressure, left heart positive pressure, and right heart positive pressure becomes abnormal six times in a row, the buzzer sounds. If it returns to normal on the sixth check, the abnormal flag ABF returns to O. Next, the pulsation control routine will be explained with reference to FIGS. 6 and 7. FIG. 6 is a left heart beat control routine. This embodiment has two pulsation control methods. One is a method used in an auxiliary artificial heart, and is a synchronous drive method in which the auxiliary artificial heart is driven in synchronization with the beats of a living heart. In this method, a synchronization signal with the living heart is determined based on an electrocardiogram or blood pressure waveform, and positive pressure is ejected for a certain period of time in accordance with the synchronization signal. Another method is an asynchronous drive method in which the motor is driven at a predetermined cycle and duty ratio regardless of the heartbeat of the living body. If the device is normal and the synchronous drive method is selected, steps 63 and subsequent steps are executed. If a synchronization signal is received while negative pressure is being applied, the solenoid valve is driven and the pressure is switched to positive pressure. Further, the set value T LONSET set by the operation SW is substituted into the timer TLON that determines the positive pressure application time. The set value TLSET set by the operation SW is substituted into the timer TL that determines the cycle. Furthermore, the set value T LPCSET set by the operation SW is substituted into the timer TLPC that determines the pressure check timing when positive pressure is applied. As a result, the timer T LPC becomes 0 after the time T LPCSET, and a positive pressure diagnosis is performed. Switches to positive pressure, and timer T LON becomes O (time T
(LONSET progress), the solenoid valve is activated and the pressure is switched to negative pressure. In addition, there is also a timer T that determines the pressure check timing when negative pressure is applied.
Substitute LNCSET. By this, the time T L
After NCSET, timer T LNC becomes O and negative pressure diagnosis is performed. After that, negative pressure is continued to be applied until a synchronization signal is received again. If the device is normal and the asynchronous drive method is selected, steps 70 and below are executed. When the period timer TL ends while negative pressure is being applied, the solenoid valve is driven to switch the pressure to positive pressure. Further, the set value T LONSET set by the operation switch is substituted into the timer T LON that determines the positive pressure application time. The setting value T LS [ set by the operation SW to the timer TL that determines the cycle
! Substitute T. Furthermore, the set value TI. set by the operation SW to the timer T LPC which determines the pressure check timing when positive pressure is applied is set. Substitute PCSET. This allows the time TLPCSET? ．． The timer TLPC goes to &, and positive pressure diagnosis is performed. Switches to positive pressure, and timer TLON becomes O (time TLONSET
progress), the solenoid valve is activated and the pressure is switched to negative pressure. In addition, there is also a timer T that determines the pressure check timing when negative pressure is applied.
Substitute LPNSET. This gives the time T LN
After CSET, timer T LNC becomes 0 and negative pressure diagnosis is performed. After this, negative pressure continues to be applied until the timer TL ends. When the abnormal flag ABF becomes 1, control using the asynchronous drive method is executed regardless of which of the synchronous drive method and the asynchronous drive method is selected. At this time, the set value T LSET, which was previously set in the main routine, is the sum of the time T LPCSAT required for the positive pressure to become sufficiently stable and the time T LNGSAT required for the negative pressure to become sufficiently stable. The set value T LONSET is set to the time T LPCSAT required for the positive pressure to become sufficiently stable. In addition, the set value T LPCSET, which was previously set in the main routine, is set to the time T LPCSAT required for the positive pressure to become sufficiently stable, and the set value T L
NCSHT is the time T required for negative pressure to become sufficiently stable.
Updated to LNCSAT. Therefore, the period of asynchronous driving is T LPCSAT + T LNCSAT, and the on time is T LPCSAT. In addition, the check time for positive pressure is time T LPCSAT after the start of positive pressure application, and the time to check negative pressure is time T LNCS after the start of negative pressure application.
It will be after AT. Note that the TLSUT and TLONS bit settings are TLPCSAT+TLNCSAT, respectively.
The time may be slightly longer than TLPCSAT. With the above control, for example, when the positive pressure of the pressure pulse generator on the left side of the heart decreases during synchronous driving, the operation is performed as shown in FIG. 9. Normal pressure diagnosis is 100% from pressure switching.
This is done after ms. Here, if the positive pressure becomes abnormal five times in a row, the next positive pressure application time is extended to 5.00 ms and the cycle is extended to 1000 ms. Furthermore, the timing of pressure diagnosis is extended until the pressure is switched. If there is an abnormality for the sixth time, the buzzer is turned on and the abnormality can be notified to the outside. Since the timing of the pressure diagnosis is extended until the pressure is switched, an abnormality will not be reported even if the rise or fall of the pressure pulse is slow as long as a normal pressure value is output. In this embodiment, a buzzer is sounded to notify of an abnormality, but other notification means such as lighting a lamp or sending a signal may be used. Alternatively, a spare pressure pulse generator may be prepared in place of the buzzer, and the apparatus may be switched to the spare pressure pulse generator in the event of an abnormality. In this case, if the setting conditions of the main pressure pulse generator and the backup pressure pulse generator differ, the driving conditions will change.
Pressure pulse changes suddenly. Therefore, the present invention is particularly effective when switching the pressure pulse generator at abnormal times. [Effects of the Invention] As described above, in the present invention, an abnormality is reported only when the pressure is definitely abnormal, so malfunctions are reduced and a highly reliable device can be provided. By reliably notifying pressure abnormalities, patients and doctors can improve their confidence in the device, allowing them to perform treatment with peace of mind.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of an embodiment using the present invention. FIG. 2 is a flowchart of the main routine of the ECU 13. FIG. 3 is a flowchart of a timer interrupt of the ECU 13. FIG. 4.5 is a flowchart showing the abnormality diagnosis routine of FIG. Figures 6 and 7 are
3 is a flowchart showing the pulsation control routine of FIG. 2; FIG. 8 is an explanatory diagram of flags used in the flowcharts from FIG. 2 onwards. FIG. 9 is an explanatory diagram for explaining the operation of the present invention. 10... Blood pump drive device, 11.12... Pressure pulse generator, . 11c,li
d. 12c, 12. d・-・Solenoid valve, 13...Electronic control unit ECU, 14...Power source, 15.16...Pressure detector, 17.18...Piping, l9...Buzzer 20...Pudgey Drive circuit, 21
...Operation SW, 35.36...Artificial heart pump.

Claims (3)

[Claims] (1) Pressure pulse generator that generates pressure pulses; Pressure detection means that detects the pressure generated by the pressure pulse generator; Pressure diagnosis that diagnoses whether the output value of the pressure detection means is normal according to pressure check timing. A drive device for a blood pump, comprising: means; pressure check timing extension means for extending the pressure check timing when the pressure diagnosis means detects a pressure abnormality; (2) The blood pump according to claim (1), further comprising pulse time extension means for extending the period or ON time of the pressure pulse of the pressure pulse generator when the pressure diagnosis means detects a pressure abnormality. drive unit. (3) Claim further comprising an abnormality notification means for notifying an abnormality when the pressure diagnosis means detects a pressure abnormality again when the pressure check timing is extended by the pressure check timing extension means ( 1) The drive device for the blood pump described above.