JPS63275352A - Control apparatus of artificial respiratory machine - Google Patents

Abstract

PURPOSE:To eliminate an abnormal state by making the respiration of a patient and artificial respiration synchronous, by estimating the next inhalation start time of the patient on the basis of the output data of a respiration detector detecting respiration operation to control the operating time of an artificial respiratory machine. CONSTITUTION:In the respiration wave form detected by a respiration detector 21, points A, C show inhalation start points and points B, D show exhalation start points. The cycle and timing of inhalation and exhalation are analyzed on the basis of said respiration wave form by a control apparatus 22 and an artificial respiratory machine 23 is controlled to perform the artificial respiration synchronous to the respiration wave form. By this method, artificial respiration made synchronous so as to help unassisted respiration can be performed even with respect to a newborn high in a respiration rate.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a control device for a ventilator used when performing artificial respiration on a patient, particularly a newborn baby.

[Conventional technology]

Conventionally, when a newborn baby has a disorder such as idiopathic respiratory distress syndrome, artificial respiration is performed using a ventilator by applying pressure regardless of spontaneous breathing.

[Problem that the invention seeks to solve]

Such conventional artificial respiration methods pose no problem when the patient is not spontaneously breathing, but they are inconvenient when artificial respiration must be performed even though the patient is spontaneously breathing. That is, in adults, the respiratory rate is 16 per minute.
~20, which is not a large number, so it is possible to synchronize the respiration of the ventilator and the patient. However, sick newborns have an extremely high respiratory rate of 60 to 100 breaths per minute, and conventional medical techniques have not been able to synchronize their breathing with each breath. As a result, an abnormal situation, medically called "fighting," often occurs in which breathing and pressurization by a ventilator collide.

The present invention has been made in view of these conventional problems, and aims to eliminate abnormal conditions by synchronizing human respiration and artificial respiration.

[Means for solving problems]

In order to achieve this objective, the ventilator control device of the present invention is provided with a respiration detector that detects the patient's breathing motion, and calculates the number of breaths, inspiratory time, expiratory time, etc. obtained from the output data of this respiration detector. The present invention is characterized by comprising means for estimating the patient's next inspiration start time based on the data and controlling the operation timing of the ventilator.

[Effect]

According to the present invention, the ventilator is controlled in synchronization with the patient's self-induced breathing motion. As shown in Figure 1,
The present invention includes a breathing detector 21 that detects the breathing pattern of a patient (opinion) P, and a control device 22 that controls a respirator 23. A respiratory waveform detected by the respiratory detector 21 is shown in FIG. In this respiratory waveform, point A and point 0 represent the start point of inhalation, and points B and D represent the start point of exhalation. The period between points A and B and between points C and D is the inhalation time, and the period between points B and C is the expiration time. This breathing detector 2
Based on the respiratory waveform detected by the control device 22
The period and timing of inhalation and exhalation are analyzed, and the artificial respirator 23 is controlled to perform artificial respiration in synchronization with the respiratory waveform.

This makes it possible to perform synchronized artificial respiration to help newborns with a high breathing rate to help their own breathing.

〔Example〕

Hereinafter, features of the present invention will be specifically explained based on embodiments shown in the drawings.

FIG. 3 is a block diagram showing an embodiment of the ventilator control device shown in FIG. 1. 1 is a carrier signal generator that generates a high frequency signal for respiration detection. This carrier signal is passed through the patient's chest through a constant current circuit 2 for keeping the current flowing between electrodes a and b attached to the chest of opinion P constant, as shown in FIG. When a carrier signal is applied to two chest electrodes and the resistance between the two electrodes is measured, the resistance changes due to respiratory movement. This signal is separated from the AC signal by an isolation transformer 3, extracted, and amplified by an amplifier 4. This amplified signal is converted into direct current by a rectifier circuit 5, and further amplified by an amplifier 6 to obtain a respiratory waveform detection cuff as shown in FIG. In order to process the analog data of this respiratory waveform by computer, A/D
A converter 8 is used to convert it into a digital signal. The computer 9 analyzes the respiratory waveform. That is, digital data of the respiratory waveform is captured every 5 to 10 m5, and the maximum and minimum values of the waveform are recognized. As a result, as shown in FIG. 2, the time point at which inspiration begins.

Calculate the exhalation start point, inspiration time, and expiration time.

The pressurization switch of the ventilator is turned on at a certain point in the expiratory phase shown in Figure 2, for example, point A, and the pressure switch is turned on from point B to point A so that the pressurization of the ventilator is performed in accordance with the inspiratory phase. Determine the time between. Next, recognize the exhalation start point B, and
The on-off switch 10 is set to turn on after the time between the two points.

The respirator 11 starts pressurizing after a certain period of time (point A-C) has elapsed after being turned on. Further, the computer 9 controls the ventilator based on data other than the respiratory waveform. When performing artificial respiration, generally
Blood oxygen partial pressure can be increased by increasing the pressurization pressure, lengthening the pressurization time, that is, the inhalation time, or increasing the positive pressure during inhalation.
It can also promote carbon dioxide excretion. The oxygen partial pressure and carbon dioxide partial pressure in the blood are continuously monitored during artificial respiration, and based on these data, the gas logic circuit of the ventilator 37-2.37-3.37-4.37- 5 (see Figure 4) to control the blood oxygen partial pressure.

Controls the partial pressure of carbon dioxide. For example, when the partial pressure of oxygen is low, the intake time is increased, and when the partial pressure of carbon dioxide is high, the pressure to be pressurized is increased.

FIG. 4 shows the configuration of a respirator used in the present invention. Compressed air and compressed oxygen are supplied from external cylinders,
The oxygen/air mixer 31 mixes them at a predetermined ratio. This mixed gas is adjusted to a predetermined flow rate by a flow rate regulator 32, and is delivered to the patient's airway by an inhalation vibrator 34 connected to a patient connection port 33.

The exhalation vibrator 35 is connected to an exhalation valve connection port 36 and exhausted through a gas logic circuit 37. The gas logic circuit 37 includes an intake start setting circuit 37-1 that starts pressurization after a certain period of time from when the on-off switch IO is turned on, and an intake time setting circuit 3.
7-2, an exhalation time setting circuit 37-3, a pressurization pressure setting circuit 37-4, and a connection positive pressure setting circuit 37-5. When synchronizing the patient's respiration and the ventilator based on the data obtained as a result of the above-mentioned respiratory waveform analysis, a signal from the computer is input manually to the inspiration start setting circuit 37-1. In addition, artificial respiration is controlled based on data from the transcutaneous 027C02 monitor, etc. For example, when the blood oxygen partial pressure is low, the exhalation time setting circuit 37-3 lengthens the inhalation time (pressurization time). Further, the pressurizing pressure setting circuit 37-4 is changed to increase the pressurizing pressure.

In addition to the respiratory waveform detector (impedance ventilation monitor) shown in Figure 3, the partial pressure of oxygen in exhaled air.

An expiratory gas monitor that instantaneously measures the partial pressure of carbon dioxide and detects the time phase of exhalation and inspiration; a pneumotachometer that is attached to an intubation tube or mask to measure expiration and inspiration volume, and ventilation volume; and a mercury-containing A mercury strain gauge can be used to measure the respiratory waveform by wrapping a vinyl tube around the chest and measuring the resistance at both ends of the tube, taking advantage of the fact that the resistance changes with breathing. Furthermore, it is also possible to use a transdermal 02/COz monitor that measures the partial pressure of oxygen 9 and carbon dioxide gas penetrating from the blood by attaching a special electrode to the skin and heating it.

In this way, more detailed control of the ventilator can be performed using information on the respiratory status obtained from another monitor.

〔Effect of the invention〕

As described above, in the present invention, the patient's breathing movement is detected and control is performed so that the timing of the inspiratory phase and the expiratory phase on the ventilator are synchronized. Therefore, even for newborns with a high breathing rate, the conflict between the self-breathing and the artificial respirator's breathing operations, that is, fighting, is eliminated, and abnormal conditions can be prevented from occurring. Since the self-scissor aids breathing, it is possible to reduce damage caused by pressurization of the lungs, and it is also possible to reduce the administered oxygen concentration, which has great medical effects.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing a schematic configuration of the present invention, FIG. 2 is an explanatory diagram of changes in respiratory waveforms and respiratory organs, FIG. 3 is a block diagram showing the configuration of an embodiment of the present invention, and FIG. FIG. 1 is a block diagram of a configuration example of a respirator applied in the invention. 1: Carrier signal generator 2: Constant current circuit 3; Isolation transformer 4-amplifier 5: Rectifier circuit 6; Amplifier 7: Respiratory waveform detection output 3: A/
D converter 9: computer 10; on-off switch 11: ventilator 21; respiration detector 22: control device 23; ventilator 31; oxygen/air mixer 32; flow regulator 33: patient connection port 34: suction Pipe 35: Exhalation vibe
36: Exhalation valve connection port 37; Gas logic circuit patent applicant Kazuhiko Muramatsu Masato Kobori (and 2 others)
Figure 4 37-25/-Q

Claims (1)

[Claims] 1. A respiration detector is provided to detect the patient's breathing movement, and the patient's next inspiration start time is estimated based on data such as the number of breaths, inspiration time, and expiration time obtained from the output data of this respiration detector. A ventilator control device characterized by comprising means for controlling the operation timing of a ventilator.