The present disclosure relates to a cardiopulmonary resuscitation system.
As a cardiopulmonary resuscitation (also referred to as CPR) method, a method for combining sternum compression with hands and mouth-to-mouth artificial respiration is known. However, it is difficult to manually perform stable and high-quality cardiopulmonary resuscitation. Therefore, a cardiopulmonary resuscitator for automatically performing sternum compression and artificial respiration has been proposed. For example, the present applicant has proposed an automatic cardiopulmonary resuscitator for performing cardiac massage by repeatedly applying an impact at adjusted regular intervals and supplying respiratory gas for ventilation at adjusted timing and duration (see, for example, Patent Literature 1).
Patent Literature 1: JP 2000-84028 A
Guidelines 2015 (2015 AHA Guidelines for CPR and ECC) for AHA cardiopulmonary resuscitation and emergency cardiovascular treatment (hereinafter also referred to as Guidelines) specify that “After tracheal intubation, sternum compression and artificial respiration are asynchronous, and continuous sternum compression is performed. Sternum compression is performed at least 100 times per minute, and artificial respiration is performed about 10 times per minute to avoid hyperventilation. In a case where a supraglottic respiratory tract device (such as a laryngeal mask) is used, continuous sternum compression may be performed only in a case where adequate ventilation is possible.”, “It is a condition for success not only in basic life support (BLS) but also in advanced life support (ALS) that continuous and efficient sternum compression is performed. Be careful with a procedure of ALS and judgment to avoid degradation of CPR quality and interruption.”, and “Interruption of sternum compression should be avoided as much as possible also in ALS, and it is inevitable to interrupt sternum compression only in a case where artificial respiration is performed, in a case where electrocardiogram (ECG) or return of spontaneous circulation (ROSC) is evaluated, and in a case where an electric shock is applied”. In addition, Guidelines recommend that compression is performed at 100 times/minute or more and the compression depth for an adult is set to 5 cm or more for high-quality sternum compression.
CPR includes a synchronous mode in which sternum compression and artificial respiration are alternately performed at a predetermined ratio and an asynchronous mode in which sternum compression and artificial respiration are performed independently and continuously. In the asynchronous mode, sternum compression is continuously performed, and a phenomenon (also referred to as fighting) in which the timing of sternum compression and the timing of artificial respiration are coincident and exhalation of a patient and inhalation by an artificial respirator occur simultaneously occurs. When fighting occurs, a risk such as reduction in cardiac output or coronary perfusion pressure, damage to an alveolus due to a high respiratory tract internal pressure, occurrence of traumatic pneumothorax, or reduction in effective alveolar ventilation amount is expected. Guidelines assume CPR based on a method with hands, and even artificial respiration is performed with hands during sternum compression, the ventilation amount is not increased due to resistance of compression, and therefore a big problem hardly occurs. Meanwhile, in CPR with an apparatus, sternum compression and artificial respiration are surely performed, and therefore a risk due to fighting is increased.
Therefore, an object of the present disclosure is to provide a cardiopulmonary resuscitation system capable of avoiding fighting in an asynchronous mode in which sternum compression and artificial respiration are performed independently and continuously.
A cardiopulmonary resuscitation system according to the present disclosure includes: a sternum compression means that includes an impact hammer for compressing the chest of a patient and repeats a sternum compression cycle having, as one cycle, a compression period in which the impact hammer is pressed against the chest and a recoil period in which the impact hammer is separated from the chest; an artificial respiration means that repeats an artificial respiration cycle having, as one cycle, an inhalation period in which respiratory gas is supplied to the patient and an exhalation period in which supply of the respiratory gas is stopped; and a control means that controls the artificial respiration means and the sternum compression means, and is characterized in that the control means executes the artificial respiration cycle a predetermined number of times per unit time while executing the sternum compression cycle a predetermined number of times per unit time, and stops pressing the impact hammer against the chest during the compression period overlapping with the inhalation period.
In the cardiopulmonary resuscitation system according to the present disclosure, in a case where the inhalation period is started during the recoil period, the control means preferably extends the recoil period executed at the start time of the inhalation period at least until the inhalation period ends. Fighting can be avoided while the number of times of artificial respiration is secured.
In the cardiopulmonary resuscitation system according to the present disclosure, in a case where the inhalation period is started during the compression period and the start time of the inhalation period is in the first half period obtained by temporally dividing the compression period into two equal parts, the control means preferably hastens start of the inhalation period by the same time as the time from the start time of the compression period overlapping with the inhalation period to the start time of the inhalation period. Fighting can be avoided even in a case where the inhalation period is started during the compression period.
In the cardiopulmonary resuscitation system according to the present disclosure, in a case where the inhalation period is started during the compression period and the start time of the inhalation period is in the second half period obtained by temporally dividing the compression period into two equal parts, the control means preferably delays start of the inhalation period by the same time as the time from the start time of the inhalation period to the end time of the compression period overlapping with the inhalation period. Fighting can be avoided even in a case where the inhalation period is started during the compression period.
In the cardiopulmonary resuscitation system according to the present disclosure, it is preferable that the control means restarts the sternum compression cycle a predetermined time after the end of the inhalation period, and the sternum compression cycle restarted is started from the compression period. By securing the exhalation time after the end of the inhalation period, it is possible to prevent an intrathoracic pressure from becoming too high.
In the cardiopulmonary resuscitation system according to the present disclosure, the artificial respiration means and the sternum compression means are preferably configured as an integral device. Portability is improved, and cardiopulmonary resuscitation can be quickly started in an early stage of critical care.
In the cardiopulmonary resuscitation system according to the present disclosure, the artificial respiration means and the sternum compression means are preferably configured as individual devices. Cardiopulmonary resuscitation can be performed with higher accuracy.
In the cardiopulmonary resuscitation system according to the present disclosure, the control means is preferably mounted on a device constituting the artificial respiration means. The sternum compression means can be small and lightweight, and sternum compression can be quickly started in an early stage of critical care.
In the cardiopulmonary resuscitation system according to the present disclosure, it is preferable that the sternum compression means includes an elevating means for vertically reciprocating the impact hammer, and a driving system of the elevating means is a gas driving system, an electric driving system, or a mixed driving system of the gas driving system and the electric driving system. By adopting the gas driving system, the setting width of the sternum compression depth can be wide, and sternum compression by a method with hands can be reproduced. By adopting the electric driving system, a device can be simpler.
The present disclosure can provide a cardiopulmonary resuscitation system capable of avoiding fighting in an asynchronous mode in which sternum compression and artificial respiration are performed independently and continuously.
Next, the present disclosure will be described in detail by describing embodiments, but the present disclosure is not construed as being limited to description thereof. As long as an effect of the present disclosure is exhibited, the embodiments may be modified variously.
In the cardiopulmonary resuscitation system 100, as illustrated in
The artificial respiration means 110 is an artificial respiration unit of the cardiopulmonary resuscitator 100. As illustrated in
The sternum compression means 120 is a sternum compression unit of the cardiopulmonary resuscitator 100. As illustrated in
The arch portion 10 has a top surface portion 11 and left and right side surface portions 12 and is disposed so as to extend over the chest of a patient. The arch portion 10 includes the impact hammer 121 projecting downward from the top surface portion 11 and movably supported in the vertical direction by the top surface portion 11 and an elevating means (elevating mechanism) 122 for vertically reciprocating the impact hammer 121. The impact hammer 121 includes an impact hammer rod 121a connected to the elevating means 122 and an impact head pad 121b attached to a lower end of the impact hammer rod 121a and pressed against the chest of a patient. In a case where the driving system of the elevating means 122 is a gas driving system, the elevating means 122 includes a cylinder 123. The cylinder 123 has a container shape and has a gas supply port (not illustrated) and a gas discharge port (not illustrated). A piston (not illustrated) and a spring (not illustrated) for pushing back the piston at the time of discharge are disposed in an internal space of the cylinder 123.
The driving system (not illustrated) of the elevating means 122 includes a driving gas supply source such as a gas cylinder or an air tank and piping connecting the driving gas supply source to the cylinder 123. In the middle of the piping, for example, a compression depth adjuster for adjusting the stroke width of the vertical reciprocating motion of the elevating means 122 and a compression solenoid valve for supplying driving gas into the cylinder 123 and discharging driving gas from the cylinder 123 are disposed. The driving gas supply source preferably serves also as a gas supply source of the artificial respiration unit 110. The compression solenoid valve is, for example, a three-way solenoid valve.
A part of the arch portion 10 is preferably the housing 101. The housing 101 houses the gas supply system of the first artificial respiration unit 110, the driving system for driving the elevating means 122, the control means of the cardiopulmonary resuscitator 100, and the like.
A pair of vertical rods 20 is disposed on the left and right sides and is fixed to fixing portions 13 disposed at lower ends of the left and right side surface portions 12 of the arch portion, respectively. For example, the vertical rod 20 is engaged with a ratchet of the fixing portion 13 to support the arch portion 10 so as to be movable in the vertical direction. As illustrated in
The back plate 30 is a plate for supporting a lower surface of the chest of a patient. For example, by engaging an engagement portion (not illustrated) such as a groove or a hole formed in the back plate 30 with a projection (not illustrated) formed at a lower end of the vertical rod 20, the back plate 30 is fixed to the arch portion 10 detachably.
The control means (hereinafter also referred to as a first control unit) is, for example, a printed circuit board. The first control unit controls the gas supply system of the first artificial respiration unit 110 and the driving system of the elevating means 122.
The first control unit closes the ventilation solenoid valve in a case where a pressure detected by the respiratory tract internal pressure sensor is equal to or higher than a predetermined pressure. It is thereby possible to prevent injection of high pressure gas into a patient.
The first control unit adjusts the frequency (number of times of ventilation) of the artificial respiration cycle by the first artificial respiration unit 110. Here, the number of times of ventilation is the number of times for performing the artificial respiration cycle in one minute, for example, 6 to 20 times/minute. The flow rate of respiratory gas by the first artificial respiration unit 110 is fixed to, for example, 24 liters/minute. The ventilation amount of respiratory gas is, for example, 200 to 600 ml/time. The length of the inhalation period is, for example, 0.5 to 1.5 seconds. The lengths of the inhalation period and the exhalation period vary depending on the flow rate of respiratory gas, the number of times of ventilation, and the ventilation amount. For example, in a case where the flow rate of respiratory gas is 24 liters/minute, the number of times of ventilation is set to 10 times/minute, and the ventilation amount is set to 200 ml/time, the inhalation period is 0.5 seconds, and the exhalation period is 5.5 seconds.
The first control unit controls the compression solenoid valve to supply driving gas into the cylinder 123 or discharge the driving gas from the inside of the cylinder 123. When the driving gas is supplied into the cylinder 123, a piston is pushed down against a repulsive force of a spring, and the impact hammer 121 moves downward. When the driving gas is discharged from the inside of the cylinder 123, the spring expands, the piston is pushed up, and the impact hammer 121 moves upward. By repeating these, the impact hammer 121 reciprocates vertically.
In addition, the first control unit adjusts the frequency of the sternum compression cycle (the number of times of compression) and the stroke width of the vertical reciprocating motion of the elevating means 122. The stroke width is switched, for example, by turning of an adjustment knob 14 by an operator. Here, the number of times of compression is the number of times for performing the sternum compression cycle in one minute, and Guidelines recommend that the number of times of compression is 100 times/minute or more. A compression period and a recoil period preferably have the same length as each other. For example, in a case where the number of times of compression is 100 times/minute, the time per sternum compression cycle is 0.6 seconds, and the compression period and the recoil period are each 0.3 seconds. The stroke width of the vertical reciprocating motion is appropriately adjusted according to a patient, but Guidelines recommend that the stroke width is 5 cm or more in an adult.
The cardiopulmonary resuscitator 100 preferably includes a mode switching unit 15. The mode switching unit 15 is a switch for switching an operation timing mode of each of the first artificial respiration unit 110 and the sternum compression unit 120. The mode switching unit 15 is, for example, a panel as illustrated in
The operation timing mode of each of the first artificial respiration unit 110 and the sternum compression unit 120 is roughly divided into a synchronous mode and an asynchronous mode.
In
The avoidance type asynchronous mode is roughly divided into three patterns depending on whether the start time of the inhalation period is during the recoil period (first example), during the first half period of the compression period (second example), or during the second half period of the compression period (third example). Next, a specific example of avoiding fighting will be described with reference to
The length of the inhalation period I4′ which has been started earlier is the same as the length of the inhalation period I4 which has been scheduled to be executed before the start time is made earlier. That is, the inhalation period I4′ is temporally shifted forward by the time t1 with respect to the inhalation period I4. In the second example, the number of times of compression is smaller than a set value by the amount overlapping with the inhalation period, and the number of times of ventilation fluctuates with respect to a set value by the amount of shift. The variation in the number of times of ventilation is preferably within ±5% of a set value.
The length of the inhalation period I5′ the start of which has been delayed is the same as the length of the inhalation period I5 which has been scheduled to be executed before the start is delayed. That is, the inhalation period I5′ is temporally shifted backward by the time t2 with respect to the inhalation period I5. In the third example, the number of times of compression is smaller than a set value by the amount overlapping with the inhalation period, and the number of times of ventilation fluctuates with respect to a set value by the amount of shift. The variation in the number of times of ventilation is preferably within ±5% of a set value.
As illustrated in
In the first to third examples, as illustrated in
In
The second artificial respiration unit 210 includes an inhalation hose (not illustrated) for injecting respiratory gas into a patient and a gas supply system (not illustrated) for supplying the respiratory gas. One end of the inhalation hose is connected to a hose insertion port (not illustrated) disposed in the housing 201 of the artificial respirator 200. The other end of the inhalation hose is connected to a mask (not illustrated) attached to a patient or a tracheal intubation tube (not illustrated). The gas supply system of the second artificial respiration unit 210 has the same basic configuration as the gas supply system of the first artificial respiration unit 110. A major difference is that a ventilation solenoid valve is disposed in the middle of the piping in the first artificial respiration unit 110, whereas a flow-controllable valve such as a flow regulating valve is disposed in the middle of the piping in the second artificial respiration unit 210.
The second control unit 230 is, for example, a printed circuit board. The second control unit 230 controls the gas supply system of the second artificial respiration unit 210. The second control unit 230 generates an external signal.
The second control unit 230 adjusts the frequency (number of times of ventilation) of the artificial respiration cycle by the second artificial respiration unit 210. Here, the number of times of ventilation is, for example, 2 to 40 times/minute. The second control unit 230 adjusts the ventilation amount of respiratory gas and the length of an inhalation period. The first artificial respiration unit 110 includes a ventilation solenoid valve, whereas the second artificial respiration unit 210 includes a flow-controllable valve such as a flow regulating valve. Therefore, the ventilation amount of respiratory gas by the second artificial respiration unit 210 can be adjusted in a wider range than the range of the ventilation amount of respiratory gas by the first artificial respiration unit 110, and is, for example, 50 to 3000 ml/time. The inhalation period of respiratory gas by the first artificial respiration unit 110 is automatically switched according to the flow rate of respiratory gas, the number of times of ventilation, and the ventilation amount, whereas the inhalation period of respiratory gas by the second artificial respiration unit 210 can be continuously switched alone, for example within a range of 0.3 to 3.0 seconds. Therefore, the second artificial respiration unit 210 can adjust the flow rate more finely than the first artificial respiration unit 110.
The external signal output unit 240 is, for example, a connection terminal of a cable (not illustrated) or a transmission unit of a wireless signal or the like, and outputs an external signal sent from the second control unit 230.
The respiratory tract internal pressure sensor 250 can detect from a negative pressure to a positive pressure, detects a respiratory tract internal pressure of a patient, and outputs a pressure signal to the second control unit 230.
In
In the cardiopulmonary resuscitation system 1, the artificial respirator 200 performs artificial respiration, and the cardiopulmonary resuscitator 100 performs only sternum compression. That is, the sternum compression unit 120 and the second artificial respiration unit 210 are in an operable state, and the first artificial respiration unit 110 is in a stopped state. At this time, the signal transmission means 300 makes it possible to transmit an external signal from the artificial respirator 200 to the cardiopulmonary resuscitator 100.
In the cardiopulmonary resuscitation system 1, a control means for controlling the artificial respiration means (artificial respirator) 200 and the sternum compression means (sternum compression unit) 120 are preferably mounted on the artificial respirator 200. By control of the sternum compression unit 120 in addition to the second artificial respiration unit 210 by the second control unit 230, the cardiopulmonary resuscitator 100 can be small and lightweight, and sternum compression can be quickly started in an early stage of critical care. The second control unit 230 generates, for example, an external signal including a remote control signal instructing the sternum compression unit 120 to perform sternum compression. The external signal including the remote control signal is output from the external signal output unit 240 and input to the external signal input unit 140 by the signal transmission means 300. The external signal including the remote control signal input by the external signal input unit 140 is sent to the first control unit 130. Upon input of the remote control signal, the first control unit 130 drives the sternum compression unit 120. In this way, the second control unit 230 remotely controls the sternum compression unit 120. In a case where the pressure detected by the respiratory tract internal pressure sensor 250 is a negative pressure, the second control unit 230 outputs a signal for opening a flow regulating valve (not illustrated) to the flow regulating valve (not illustrated) and supplies respiratory gas from the second artificial respiration unit 210.
Avoidance of fighting by the second control unit 230 is performed in a similar manner to those in
Up to this point, the form in which the elevating means 122 of the sternum compression means 120 is a gas driving system has been described, but the present disclosure is not limited to the driving system of the elevating means 122. The driving system of the elevating means 122 may be, for example, an electric driving system or a mixed driving system of a gas driving system and an electric driving system. In a case where the driving system of the elevating means 122 is a gas driving system, according to the classification of the medical apparatus law or the like, the sternum compression means 120 may also be referred to as a “mechanical cardiopulmonary artificial resuscitator”. By adopting the gas driving system, the setting width of the sternum compression depth can be wide, and sternum compression by a method with hands can be reproduced. In a case where the driving system of the elevating means 122 is an electric driving system, according to the classification of the medical apparatus law or the like, the sternum compression means 120 may also be referred to as an “electric cardiopulmonary artificial resuscitator”. By adopting the electric driving system, a device can be simpler. The electric driving system is, for example, an internal battery, an external battery, an external power source such as an AC 100 V power source, or a combination thereof. In a case where the electric driving system is adopted as the driving system of the elevating means 122, the impact hammer 121 reciprocates vertically by motor driving, for example.
Number | Date | Country | Kind |
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2016-044363 | Mar 2016 | JP | national |
Filing Document | Filing Date | Country | Kind |
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PCT/JP2017/008420 | 3/3/2017 | WO | 00 |