JPS6355337B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for monitoring apnea in premature infants and the like.

Devices used to monitor the breathing of premature infants, etc., have been known for detecting breathing using the thoracic impedance method, measuring the number of breaths per minute and the apnea time, and generating an alarm to notify of a dangerous situation. It is being Monitoring for apnea is especially important in premature infants.

There are many diseases that can cause apnea.
For example, sudden apnea, hypoxemia, pulmonary disease, anemia, reflex, central, patent ductus arteriosus, etc. To monitor the progress of these diseases, the above-mentioned respiratory rate,
Monitoring apnea time alone was extremely insufficient.

In view of this problem, it is an object of the present invention to make it possible to know the progress of a disease accompanied by the occurrence of apnea, and to enable a doctor to make a diagnosis more accurately and easily.

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of the detection section of the apnea monitoring device according to the present invention. Moreover, FIG. 2 is a waveform diagram of each part of FIG. 1 showing the operation.

A pair of electrodes 2a and 2b are attached to the chest of the premature infant 1, and a small constant current (100 μA) of approximately 50 Hz is applied to these electrodes from an oscillator 3 via a constant current circuit 4 as shown in FIG. 2A. Given. The thoracic impedance between the electrodes 2a and 2b changes as shown in Figure 2B with breathing (especially movement of the diaphragm).
Due to this impedance change, the electrodes 2a, 2b
The voltage across the (amplitude of the applied high frequency) is modulated as shown in FIG. This modulated signal is sent to the rectifier circuit 7 via the amplifier 6, where it is detected and
It is sent to the detection circuit 8 as a respiration detection signal shown in FIG. 2D.

In the detection circuit 8, for example, a constant reference voltage and a second
The apnea state is detected by comparing the level of the respiration detection signal in Figure D. The apnea detection signal S is sent to the count display section shown in FIG.

FIG. 3 is a block diagram of the count display section of the apnea monitoring device of the present invention, and FIG. 4 is a time chart for explaining its operation.

The apnea detection signal S (E in FIG. 4) detected by the detection section in FIG. 1 is given to the counter 11 from the terminal 10. The counter 11 is reset at intervals of, for example, 8 hours determined by the time interval signal d of FIG. 4D generated from the timer 12.
The number of apneas within an 8 hour interval is counted as shown in Figure 4F.

The timer 12 also generates a time elapsed signal c, for example every hour, as shown in FIG. 4C, and supplies it to the counter 13. The count output b (Fig. 4B) of the counter 13 is given to the LED 15 through the LED drive circuit 14, and is displayed as time elapsed for each hour as 1, 2, 3...0 as shown in Fig. 4A. Ru. Note that the counter 13 is reset at every time interval signal d every 8 hours.

The apnea count data f counted by the counter 11 is given to the selection terminal 16a of the selector 16 and also given to the memory 17. The time interval signal d is input to the memory 17 for storing the command.
is given, and the apnea frequency data measured every 8 hours is stored here as shown in FIG. 4G.

The output g of the memory 17 is
is applied to the selection terminal 16b of the adder 18.
given to. The output f of the counter 11 is given to the other addition input of the adder 18, and the memory 17
The apnea frequency data in the previous 8-hour interval, which is the output of the counter 11, and the apnea frequency data, which is the output of the counter 11 currently counting, are added (f+g) as shown in FIG. 4G. The addition output h is given to the selection terminal 16c of the selector 16.

The selector 16 is operated by a switch SW, and the input data of the selection terminals 16a to 16c is changed to the fourth one every time the operation pulse i (FIG. 4 I) is generated.
They are sequentially selected by control signals such as those shown in Figures K, L, and M. The selected data (any one of the output f of the counter 11, the output g of the memory 17, and the output h of the adder 18) is sent via the drive circuit 19.
LED I 20 is provided to selectively display the current apnea count, the stored apnea count within the previous 8 hour interval, or the sum thereof.

In addition, when the selector 16 is switched, the indicator light 2
1 and 22, a lighting indication "M" or "Σ" is performed to indicate whether the display of the LED 20 is a display of memory data or a display of sum data. Note that when these indicator lights 21 and 22 are not lit, the count value of the counter 11 is displayed.
At this time, the drive circuit 14 for the LED 15 described above is turned on and the elapsed time is displayed.

To illustrate an example of the operation of the count display section in FIG. 3, first, when the switching control signal shown in FIG. 4 K is generated, the count output of the counter 11 is selected by the selector 16 as shown in FIG. 4 J; As shown in Figure 4 N
The number of apneas is displayed on the LED 20 as 1, 2, 3, etc. (“3” at time t ₁ ).

When the switching control signal shown in FIG. 4L is generated, the output of the memory 17 is selected by the selector 16. At time t ₂ , the display on LED 20 is N in Figure 4.
However, at time _t2 when the 8-hour interval ends, the memory content "10" is displayed.

Further, when the switching signal shown in FIG. 4M is generated, the output of the adder 18 is selected by the selector ₁₆ as shown in FIG. (Memory data “10” + count data “4”) is displayed.

As described above, the apnea monitoring device of the present invention includes a detection unit 8 that detects apnea in a patient, a counter unit 11 that counts detected apnea signals, and a memory unit 17 that stores the counted number of apneas. , the output of this memory section 17 and the counter section 11
an adding section 18 that adds the outputs of the counter section 11, the memory section 17, and the adding section 18, a display section 20 that switches and displays the outputs of the counter section 11, the memory section 17, and the adding section 18, respectively, and a time elapsed signal c and a time interval signal d for each set time width. a timer unit 12 that generates each of
2, and a display section 15 for displaying elapsed time data based on the elapsed time signal c outputted from No. 2.

Every time the timer section 12 outputs the time interval signal d, the number of apneas counted by the counter section 11 is stored in the memory section 17, and the counter section 11 is reset to count the number of apneas. This is a configuration that starts.

Therefore, according to the present invention, by switching the display, it is possible to know the number of apneas up to the present within the set time range from the output of the counter section 11, and also to know the number of apneas within the previous set time range, that is, the past number of apneas. The history of the patient can be known from the output of the memory section 17, and furthermore, the total number of apneas up to the present including the past history can be known from the output of the addition section 18. This makes it possible to grasp the progress of the disease accompanied by the occurrence of apnea using the data on the three apnea counts as well as the display of the elapsed time on the display unit 15, making it easier for the doctor to make a diagnosis. Be accurate and easy.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of the detection section of the apnea monitor according to the present invention, FIG. 2 is a waveform diagram of each section showing the operation of FIG. 1, and FIG. 3 is a diagram of the count display section of the apnea monitor according to the present invention. The block diagram, FIG. 4, is a time chart for explaining the operation of FIG. 3. In addition, in the symbols used in the drawings, 8...detection circuit, 11...counter, 12...timer, 1
3...Counter, 15...LED, 16...
Selector, 17...Memory, 18...Adder, 20...LED.

Claims (1)

[Claims] 1. A detection unit that detects apnea in a patient, a counter unit that counts detected apnea signals, a memory unit that stores the counted number of apneas, and an output of this memory unit. an addition section that adds the outputs of the counter section, a display section that switches and displays the outputs of the counter section, memory section, and addition section, respectively, and generates a time elapsed signal and a time interval signal for each set time width, respectively. A timer section and a display section for displaying elapsed time data based on a time elapsed signal output from the timer section, and each time the timer section outputs the time interval signal, the time interval signal is counted by the counter section. An apnea monitoring device characterized in that the number of apneas that have been detected is stored in the memory section, and the counter section is reset to start counting the number of apneas.