JPH0317502B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to the configuration of a sensor for controlling the start timing of inspiration in an artificial respirator.

[Prior Art] Conventionally, artificial respiration equipment has been used to assist or artificially perform breathing when patients are unable to ventilate effectively due to respiratory muscle disease, lung breathing disease, etc. However, with the volume-controlled respirator, the amount of respiration can be clearly determined, and breathing may stop or occur.
It has come to be widely used because it is highly safe and allows for early detection of decreased ventilation, as well as the ability to easily adjust the amount of ventilation.

In this conventional volume-controlled breathing apparatus, as shown in FIG. It is connected to the tracheal tube 8, and a cuff 50 is provided in a circumferential manner near the mouth end 8a of the tracheal tube 8. This cuff 50 is inflated and deflated via a communicating tube 51.

When using the conventional device described above, please refer to the 19th
As shown in the figure, the tracheal tube 8 is inserted into the trachea 52 with the cuff deflated 50', and then the cuff 50 is inflated to close the trachea 52 so that the internal airway pressure matches that in the tracheal tube 8, It functions so that a set amount of oxygen, etc. (for example, 500 to 700 c.c./time) is delivered into the intake pipe 6 when the airway internal pressure falls below the set value.

In addition, in the case of children, if you use cuff 50,
After the tracheal tube 8 is removed, the cuff 50 cannot be used because the area becomes narrowed, which is dangerous, and it is difficult to measure the airway pressure. The method used is to constantly supply oxygen to the child so that the child can inhale freely, while closing the exhalation valve at a rate of between 5 and 40 times per minute, forcing the child to breathe only at this time.

[Problems to be Solved by the Present Invention] Regarding the use of the conventional volume-controlled artificial respirator described above, there are few problems during controlled breathing, but when the withdrawal phase is reached, intermittent forced breathing or continuous positive pressure breathing Once in this mode, children often have difficulty synchronizing well. The cause of this is that neonates and infants have weak muscle strength, and since a cuffed tracheal tube is used, leakage from the larynx is inevitable, and the relatively large capacity of the circuit makes it difficult for the infant to make inspiratory efforts. This is thought to be due to the fact that the airway internal pressure does not drop sufficiently, and as a result, the intake valve cannot be opened or the timing is delayed. In addition, in cases of open-heart surgery in newborns and infants with poor lung conditions, in addition to low lung compliance, the thoracic skeleton is underdeveloped, so even when the patient contracts the diaphragm, the thorax at the diaphragm attachment point collapses. However, there was a problem that effective breathing exercise was hindered.

On the other hand, with the above-mentioned constant flow type artificial respirator, monitoring of respiratory volume is inaccurate and the ventilation volume needs to be changed if the lung condition changes, so it may not be applicable to critically ill patients. There is a problem that there is.

The object of the present invention is to provide a sensor for controlling the timing of starting air supply in an artificial respirator that can be applied particularly to newborns and infants less than 6 months old, in order to solve the above-mentioned problems. is to provide.

[Means for Solving the Problems] In order to achieve the above-mentioned object, the present invention aims to
Based on the knowledge of the phenomenon of depressions and bulges on the body surface observed in the early stages of inspiration in newborns and infants under 1 month old, a sensor for controlling an artificial respiration device was constructed as follows.

That is, a device connected to input a signal to a control unit that controls sending oxygen, etc. from various gas cylinders to the tracheal tube in accordance with an input signal in an artificial respiration device is designed to detect depressions or depressions on the surface of the human body due to thoracic movement. a sensing portion having a function of sensing a pressure difference as a result of swelling and outputting this as a signal; a fixing member for fixing this sensing portion onto the recessed portion or the bulging portion; and controlling the output signal of the sensing portion as described above. and a conductive part that conducts electricity to the part.

Depressions on the human body surface due to thoracic movement occur in the intercostal and suprasternal fossa of newborns and infants under 6 months of age.
It is particularly noticeable in the intercostal areas where the diaphragm attaches, and the extent of the depression varies from 2 to 10 mm depending on the child's physique and severity. The cause of this phenomenon is that the diaphragm moves downward at the start of exhalation to expand the lungs, so the lungs do not fully expand, and as a result, the part where the diaphragm attaches is pulled inward. This is also thought to be because the chest is still flexible. Therefore, this depression phenomenon occurs almost at the same time as the start of inspiration. Further, the bulge occurs near the center of the abdomen with a slight delay compared to the depression due to the downward movement of the diaphragm accompanying the start of breathing, and the degree of bulge is approximately 2 to 10 mm.

The above-mentioned sense part of the present invention is first of a solid type, which has an expandable and contractible outer shell and a flexible spacer inside to maintain the outer shell in a fixed shape, and one which directly converts the pressure difference into an electric current. In addition to being able to use solid-state sensors such as diodes and pressure-sensitive transistors that convert and capture signals, functional components such as variable resistors that should be installed on the belt that surrounds the body and that extend in the longitudinal direction of the belt can be used. It includes a device that captures changes in length along the belt and has a spacer at a predetermined position on the belt. This functional member detects changes in electrical quantities, and includes a variable resistor that detects changes in impedance, as well as a solenoid coil that detects changes in inductance. The other sense section is one that detects changes in internal pressure, but may also be a balloon sensor that freely changes its outer shape according to the internal pressure.

In addition, when the solid type sensor described above is applied, the present invention also includes a configuration in which an elastic member is interposed between the sensor and the fixing member. Examples of this elastic member include folded gauze, sponge, and the like.

Further, the fixing member may be a normal adhesive tape that fixes the sense portion onto the recess or bulge and adhesively fixes it around the area, or a hard plastic plate in the form of a tape strip, etc. An adhesive layer may be formed on both ends or the entire surface of one side. Furthermore, the above-mentioned plastic plate can be formed of an elastic material and deformed into a flat shape or a concave shape at the center. It may also be a belt that can be wrapped around the body.

In addition, in the present invention, the above-mentioned sense part and
The elastic member and the fixing member are not required to be integrally fixed in advance.

In addition, the conductive part is a conductive material such as an electric wire when the sense part consists of a functional member such as the above-mentioned fixed sensor or variable resistor. A connector connected to a terminal of the terminal can be provided. Further, when the sensing portion is the above-mentioned balloon sensor, the conduction portion is formed of a tracheal material such as a tube.
This tracheal material is connected in a state where it communicates with the inside of the balloon, which is the sense part. A connector portion that can be connected to a transducer on the main body of the artificial respirator can be provided at the extreme end of the tracheal material. In this case, it is necessary to incorporate a transducer for converting changes in atmospheric pressure into electrical signals on the side of the above-mentioned control section to which the connector section is connected.

[Function] Since the sensing portion in the control sensor of the artificial respiration device according to the present invention senses the phenomenon of depression or bulge appearing in a certain part on the surface of the human body, the occurrence of this depression or bulge is caused by the occurrence of the depression or bulge in the patient. Coupled with the fact that this almost coincides with the early stage of the start of inhalation, it is possible to supply just enough oxygen or the like according to the initial setting amount for the artificial respirator with respect to the patient's breathing movement.

In addition, since the sense part detects the phenomena of depressions or bulges that appear in certain small areas on the surface of the human body, fixing to the sense part may be done with adhesive that only extends around the periphery of the depression or bulge. An extremely simple fixing member such as tape is sufficient.

In addition, as mentioned above, if the configuration includes an elastic member between the sensor and the fixed member when it is loaded on the sense part, the elasticity of this elastic member will keep the sense part in a stable state when it is first fixed. This makes it possible to fix the depression or bulge, and serves to improve the detection accuracy of the depression or bulge.

Furthermore, the above-mentioned effect of the elastic member is different when a plastic plate in the form of an elastic tape piece is used as the fixing member (in this case, especially when the central part of the plastic plate is formed in a concave shape, the elastic effect is ), or if a balloon sensor is used as the sensing part, the elasticity generated in the balloon itself is also exerted.

Furthermore, when the balloon sensor described above is used, when the detection target is a recessed portion, the deformed portion extends to every corner of the recessed portion according to the freely deformable property of the balloon, so that more reliable detection can be achieved.

[Example] FIG. 1 is a wiring and piping diagram of a control sensor according to the present invention in an artificial respiration device. The artificial respiration apparatus main body 1 includes a control section 2 built therein. Further, a sense section 3 constituting a control sensor according to the present invention is connected to a transducer related to the control section 2 via a tube 4. Further, an inhalation pipe 6 and an exhalation pipe 7 are connected to the artificial respiration apparatus main body 1 by fitting a connector portion at one end into a socket portion thereof. The inspiratory pipe 6 and the expiratory pipe 7 are each converged at the other end by a branch pipe 5, and are connected to a tracheal tube 8 via this branch pipe 5. Branch pipe 5
A valve for selecting the communication state between the tracheal tube 8 and the inspiratory pipe 6 or the expiratory pipe 7 according to the direction of airflow is provided inside. In addition, an air compressor 9 is connected to the main body 1 of the artificial respiration device via a pressure reducing valve, a rotameter, a control valve 10, etc.
Further, an oxygen cylinder 11 and a nitrogen cylinder (or compressed air cylinder) 12 are connected via piping via a pressure reducing valve, a needle valve, a rotameter, etc.
Note that 13 is a recorder for recording consumed oxygen and the like.

The control unit 2 controls the control valve 10 to open according to the contents set in advance by a setting device included in the device main body 1, and to open the electromagnetic valve in response to a signal input from the sense unit 3. , operates to forcibly feed oxygen, air, nitrogen, or a mixture thereof from the cylinders 11 and/or 12 to the tracheal tube 8 via the intake pipe 6, depending on the settings.

Further, FIGS. 2 and 3 show specific positions on the body where depressions or bulges, which are the parts to be detected, occur. 16 is a rib, 17 is a sternum, 18 is a tibia, 19 is a spine, 20 is a lung, 21 is a pleura, 22 is a diaphragm, and 23 is a diaphragm attachment part. In newborn and infant patients, depressions are clearly observed in the intercostal space 24 and suprasternal fossa 25, and a bulge is clearly observed in the center of the abdomen 26.

FIG. 4 shows a sensor for controlling an artificial respiration device according to a first embodiment of the present invention. This sensor consists of a flat pressure sensing part 3, a folded multi-layered gauze 30 as an elastic member, and an adhesive tape 31 as a fixing member. As shown in FIG. 5, each of these components is assembled by applying pressure sensitive adhesive tape to the air pressure sensing part 3 through a gauze 30 loaded on top thereof, with the pressure sensitive surface aligned with the surface of the intercostal recess target part 24. They are integrated by being fixed by 31. In addition, more specifically, the third
It is shown by a chain double-dashed line in the figure. The air pressure sensing section 3 is composed of an inflatable outer shell and a flexible spacer 3a disposed inside the outer shell.
are connected in a communicating state, and the end of the tube 4 is connected to a transducer in the main body 1 of the apparatus.
The spacer 3a maintains the flat shape of the sense part 3 when the outer shell expands and contracts, and is slightly compressed and deformed especially when pressurized, so that changes in internal pressure due to the deformation are transmitted through the tube 4 and the transducer. and is input to the control section 2 as an electrical signal. Therefore, the atmospheric pressure sensing section 3 was initially mainly equipped with gauze 30.
However, as shown in Fig. 6, when the depression 24a occurs, the applied pressure attenuates or becomes unpressurized, and this change in state is captured as an electrical signal. and is input to the control section 2. At this time, the control function of the control unit 2 causes the intake pipe 6 to
A valve leading to the is opened and a predetermined amount of oxygen, etc.
80c.c.) will be delivered from the tracheal tube 8 into the patient's trachea.

Further, FIG. 7 shows a sensor for controlling an artificial respiration apparatus according to a second embodiment of the present invention. In this sensor, a fixing member is an elastic plastic plate 33 which is shaped like a piece of tape and has a concave central part.This plastic plate 33 has an air pressure sensing section on the convex side of the central part based on the concave shape. 3 and are fixed to each other via a sponge 32 as an elastic member. In addition, this plastic plate 33 has adhesive layers 34, 34 on both end surfaces on the convex side, respectively, and is arranged in alignment with the recess target area 24, and by adhering each adhesive layer 34 in the vicinity thereof, a sense is created. Part 3 etc. are fixed. At this time, the pressure-sensitive surface of the sense section 3 is under pressure due to the elasticity caused by the deformation of the sponge 32 and the plastic plate 33. Therefore, when the depression 24a is formed, as shown in FIG. 9, the pressure applied to the sensing portion 3 changes to reduced pressure or no pressure, and this is detected in the same manner as described above.

Further, FIG. 10 shows a sensor for controlling an artificial respiration apparatus according to a third embodiment of the present invention. In this sensor, adhesive layers 36 and 36 are provided on the bottom surface of both ends, respectively.
A hard plastic plate 35 in the form of a tape strip having
and a balloon sensor 37 whose upper portion is fixed to the center of the lower surface of the plastic plate 35. 37a indicates the fixed portion. A tube 38 is connected to the balloon sensor 37 through a connector portion 38a, and the end of the tube 38 is connected to a transducer of the main body 1 of the device. Initially, the balloon sensor 37 is in a compressed deformed state between it and the recess target portion 24, as shown in FIG. Therefore, when the depression 24a occurs, the balloon sensor 37 is activated as shown in FIG.
becomes expanded and its internal pressure decreases. This decrease in atmospheric pressure is captured as an electrical signal and controlled in the same manner as described above. At this time, the balloon sensor 37 itself exhibits an elastic action similar to that of the elastic member described above, and the freely deformable nature of the balloon sensor 37 makes it possible to reliably detect the depression, so that the extent of the depression is small. The sensor function can be fully utilized even in the case of

Further, FIG. 13 shows a configuration applied to a portion to be bulged. This illustration shows the case where the sensor for controlling the artificial respiration apparatus in the first embodiment described above is applied, and the sense part 3 is attached to the swelling target part in the center of the abdomen 26.
The pressure-sensitive surfaces of the two are placed together and fixed with adhesive tape 31 via gauze 30. In this case, the sense part 3 is initially fixed in a pre-inflated state, and the first
As shown in FIG. 4, when the bulge 26a occurs, the sense portion 3 is compressed and deformed. Changes in the internal pressure of the sense section 3 due to this compression are detected as a signal in the same manner as described above.

Further, FIG. 15 shows a sensor 40 for controlling an artificial respiration apparatus according to a fourth embodiment of the present invention.
In this sensor 40, a belt portion 41 has an elastic portion 42 that elastically expands and contracts along the longitudinal direction.
Both ends are joined like a joining part 43 to form an annular shape. Further, an electric resistor 44 is fixedly provided on the belt 41, spanning the elastic portion 42 and relating to the combination of the concave portion 45 and the convex portion 46 in contact with each other. The impedance of the electrical resistor 44 can be changed by changing its length as the expandable portion 42 expands and contracts. Further, on the inner surface of the belt 41, as shown in FIG. 16, spacers 48, 48 are provided corresponding to the recess target portions 24. Initially, the belt 41 is wrapped around the body under some tension, but when the recess 24a occurs, the spacers 48, 48 fall into this, and the circumference of the belt 41 is reduced by the elasticity of the elastic part 42. This causes the impedance value of the electrical resistor 44 to decrease. By monitoring changes in this impedance value, the control unit 2
is operated.

Further, the above-mentioned sensor 40 is similarly applied to the bulging target portion. In this case, a change in impedance that increases due to the elongation of the circumferential length of the belt portion 41 due to the swelling is detected.

Application Example 1 Next, an application example of the control sensor in the first embodiment will be shown. The sensing portion 3 of this control sensor has a disk shape with a diameter of 23 mm and a thickness of 3 mm, and has a minimum detection pressure of 1 mmHg, and is connected in advance to the transducer of the apparatus main body 1 via a tube 4. This control sensor is fixed between the ribs of an infant (weight: 6 kg) who has undergone thoracotomy in the manner shown by the two-dot chain line in Fig. 3, and the tracheal tube 8 is inserted into the patient's trachea 41 without a cuff. Inserted.

When this control sensor was applied, the pressure change detected by the sense unit 3 was monitored and the results recorded by a printer are shown as characteristic a in FIG. 17. At the same time, a 16-gauge angiogram was punctured and fixed, and the change in airway pressure was shown as characteristic b, and the electrocardiogram characteristic c was recorded using a printer. As a result, the property a
It is confirmed that the pressure detected by thoracic movement exhibits a trough-shaped waveform of -3 to 5 mmHg at the beginning of inspiration. Also, in comparing characteristic a and characteristic b,
When comparing the peak position of the trough of characteristic a with the peak position of the peak of characteristic b, it is recognized that intermittent forced breathing is often involved regardless of breathing from the change in airway pressure, and the thoracic It is confirmed that exercise, that is, respiratory effort, is hardly reflected in the airway pressure. In addition, in comparison with characteristic c, the peak in characteristic c is thought to be mainly associated with body movement,
It is confirmed that the electrocardiogram waveform is also unrelated to respiratory motion. From these facts, it can be seen that the control sensor of the present invention can sufficiently deal with the problem of artifacts accompanying body movements such as movements of limbs. Therefore, it has also been confirmed that by starting air supply in accordance with the peak of the trough of characteristic a, the patient adapts to assisted breathing without pain.

Application Example 2 Next, the control sensor in the first embodiment was applied to a 23-day-old newborn (weight: 2.2 kg) in the same manner as in Application Example 1, and the pressure change at the sensing part 3 was measured. was monitored and recorded by a printer, and the results are shown in FIG. 18 as characteristic d. 2 mm according to the spike e ₁ to e ₈ position at each peak of the valley of this characteristic d
When the pressure is reduced to Hg or more, the control unit 2 operates and the intake pipe 6
The valve was set so that the air supply valve was opened.
As a result, the patient adapted to assisted breathing without any pain.

[Effects of the Invention] Since the present invention is configured as described above, it has the following effects.

First, since it is possible to quickly and accurately detect when the patient starts breathing and open the intake valve as soon as possible, the patient can breathe easily by adapting to the patient's movements.

In addition, the control sensor of the present invention detects changes in small parts of the body and can be fixed in an extremely simple configuration, making it suitable for use on children who are weak and move a lot. It has few harmful effects, is safe and advantageous.

In addition, since the detection is reliable, it is possible to reliably supply air even in an emergency such as when a patient hates the tracheal tube and becomes violent.

[Brief explanation of the drawing]

Fig. 1... Wiring and piping diagram of the control sensor of the artificial respiration device of the present invention, Fig. 2... Partial cross-sectional front view of the human chest, Fig. 3... Longitudinal cross-sectional view of the human body, Fig. 4... Artificial respiration of the present invention A perspective view of a control sensor of the device, FIG. 5...an explanatory longitudinal sectional view, FIG. 6...an explanatory longitudinal sectional view, FIG. 7...a front view, FIG. 8...an explanatory longitudinal sectional view, FIG. 9...An explanatory longitudinal sectional view, FIG. 10...A perspective view, FIG. 11...An explanatory longitudinal sectional view, FIG. 12...
13...Explanatory longitudinal sectional view, Fig. 14...Explanatory longitudinal sectional view, Fig. 15...Perspective view, Fig. 16...Explanatory longitudinal sectional view, 17th FIG. 18 is a characteristic diagram, FIG. 19 is a partial vertical sectional view of a conventional device. Explanation of drawing symbols, 1... Artificial respirator body, 2
...Control section, 3...Sense section, 24a...Recess,
26a...bulge, 32...elastic member, 31, 32
...fixing member, 35...fixing plate, 37...balloon sensor, 40...belt type sensor, 44...
electrical resistor.

Claims (1)

[Scope of Claims] 1. A device connected to input signals to a control unit that controls sending oxygen, etc. from various gas cylinders to the tracheal tube in accordance with input signals in an artificial respirator, a sensing portion having a function of sensing a pressure difference as a result of the depression or bulge on the top and outputting this as a signal; a fixing member for fixing the sensing portion onto the depression or bulge; A sensor for controlling an artificial respiration apparatus, comprising a conductive part that transmits an output signal to the control part. 2. The artificial respiration according to claim 1, wherein the sense section is of a solid type, and the solid type sense section is fixed to the fixing member with an elastic member interposed between them. Sensors for controlling equipment. 3. The sense section is constituted by a balloon partially fixed on the surface of the fixing member, and the conduction section is constituted by a tube that transmits a change in shape in the balloon to the control section as a change in air pressure. A sensor for controlling an artificial respiration device according to claim 1, characterized by: 4. Claim 1, wherein the fixing member is made of an elastic plate having an adhesive layer on both end surfaces for fixing the sense part in the shape of a tape piece.
A sensor for controlling an artificial respiration device according to item 2 or 3. 5. The sensor for controlling an artificial respiration apparatus according to claim 4, wherein the central portion of the elastic plate is formed in a concave shape in the direction in which the recess is generated. 6. The fixing member comprises a belt that can be wrapped around the body including the area where the depression or bulge occurs, and the sense part is fixed to a part of the belt facing the depression or bulge. The artificial respiration apparatus according to claim 1, comprising a spacer and a functional member capable of outputting a change in length along the longitudinal direction of the belt as a change in various electrical quantities. Control sensor.