JPH0414993B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a pulsatile artificial heart pump.

(Prior Art) Conventional pulsatile artificial heart pumps are air-driven pumps that circulate blood by repeatedly expanding and contracting a blood chamber made of an elastic sac housed in a housing. There is also a mechanically driven type that circulates blood by mechanically repeating expansion and contraction of a blood chamber made of an elastic sac.

(Problem to be Solved by the Invention) However, in the air-driven pulsatile artificial heart pump described above, the wall thickness of the blood chamber is made as thin as possible to increase response to venous pressure on the inflow side. As a result, pinholes and cracks are likely to occur in the blood chamber, and during pumping, both during pressurization and negative pressure, air gets mixed into the blood and immediately destroys the living body. Accidents that lead to the death of people occur. Since the time between the occurrence of this pinhole and the fatal air embolism is less than one second in just one pump cycle, the occurrence immediately leads to death. However, at present, there is no idea at all to extend this allowable time of less than 1 second, detect pinholes or cracks during pumping, and replace the pump to save lives. The emphasis is on preventing the occurrence of For this reason, instead of air, pressurization is performed using carbon dioxide or helium gas, which does not cause death even if a small amount gets mixed into the blood, but this requires an expensive and complicated closed type device, which increases the cost. Not only that, but even carbon dioxide gas could be fatal if it got into the blood in large quantities. In addition, with the mechanical drive method, if a pinhole or crack occurs, blood will flow out when pressurized, so it is easy to detect the occurrence of a pinhole or crack, but before detection, when the blood chamber is elastically restored and expanded, blood flows out. Due to the negative pressure generated within the chamber, blood gets mixed in and at the same time air is also sucked in from the outside, causing the problem that air gets mixed into the blood and can kill living organisms, so it is as dangerous as the air-driven method. It was hot.

(Means for Solving the Problems) The present invention relates to a pulsating artificial heart pump that solves the conventional problems as described above.
In a pulsating artificial heart pump that circulates blood by repeated contractions, a physiological saline chamber made of an elastic sac that encloses a blood chamber made of an elastic sac is provided in the housing, and a physiological saline chamber is provided in the housing. This chamber is characterized by being provided with an air supply/discharge hole for pressurizing or depressurizing the physiological saline inside the chamber, and also provided with a detection mechanism for detecting that blood or air has entered the saline chamber.

(Function) Such a pulsating artificial heart pump applies pressure through an air supply/discharge hole by connecting a blood inflow pipe and a blood discharge pipe connected to a blood chamber of an elastic sac to blood vessels of the living body. When air is supplied into the housing, the saline in the saline chamber made of an elastic sac inside the housing is pressurized, so that the blood chamber covered by the saline chamber is filled with saline. The blood in the blood chamber is then discharged into the body's circulatory system through the blood discharge tube.
Next, the pressurization to the saline chamber is stopped, the air in the housing is exhausted from the air supply/exhaust hole, and the saline chamber is expanded by applying negative pressure inside the housing or by the restoring force of the saline chamber itself. Then, the blood chamber expands and blood from inside the body flows back into the blood chamber and fills it, and the same action is repeated and pumping is performed, but if there is a pinhole or crack in the blood chamber. If this occurs, blood in the blood chamber flows out into the saline chamber, or air enters from the outside, this is detected because the saline chamber is equipped with a detection mechanism that detects that blood or air has entered the chamber. The mechanism can detect blood or air, and
Since the blood chamber is surrounded by a saline chamber, air cannot enter the blood chamber, so if the detection mechanism detects an abnormality, it will stop pumping and switch to a backup artificial heart pump. There is enough time to do this, and it will not cause the death of the living organism.

(Example) Next, the present invention will be described in detail based on a first example shown in FIG.

Reference numeral 1 denotes a housing, and the housing 1 has an insertion hole 1 for drawing out a blood inflow pipe 2a and a blood discharge pipe 2b of a blood chamber 2, which will be described later.
A, an insertion hole 1b, and an air supply/discharge hole 1c are transparent. Reference numeral 2 denotes a blood chamber made of an elastic sac housed within the housing 1, and check valves 2c and 2d are attached to a blood inflow pipe 2a and a blood discharge pipe 2b connected to the blood chamber 2. Reference numeral 3 denotes a physiological saline chamber made of an elastic bag housed within the housing 1 and surrounding the blood chamber 2, and a portion of the physiological saline chamber 3 is fixed to the inner surface of the housing.
4 is a detection mechanism that detects blood and air bubbles mixed into the saline chamber 3;
In this embodiment, a transparent detection chamber 4a is connected to the saline chamber 3, and blood that is mixed into the saline when a pinhole or crack occurs in the blood chamber 2 or the saline chamber 3 is detected. The occurrence of pinholes and cracks can be immediately detected by detecting air bubbles and air bubbles with an optical sensor installed in the detection chamber 4a, but if a chemical sensor is used instead of the optical sensor, the detection chamber It is not necessary to make the detection chamber 4a transparent, and if the transparent detection chamber 4a is installed at the highest position of the saline chamber 3, pinholes or cracks in the saline chamber 3 can prevent water from entering the saline. Pinholes can be detected more quickly because mixed air can easily collect. Reference numeral 5 denotes a three-way stopcock provided in the detection mechanism 4, which allows saline to be injected into the saline chamber 3 while removing air.

With this configuration, first, the blood inflow pipe 2a and the blood discharge pipe 2b are connected to the blood vessels of the living body, and then pressurized air is sent into the housing 1 from the air supply/discharge hole 1c using a drive device (not shown). For example, since the physiological saline chamber 3 is pressurized and contracts, the blood chamber 2 enclosed within the physiological saline chamber 3 is pressurized by the physiological saline and contracts, causing the blood chamber 2 within the blood chamber 2 to contract. The blood will be discharged to the living body side through the blood discharge tube 2b, and if a slight negative pressure is applied to the housing 1 after discharge is completed, the saline will be depressurized as the saline chamber 3 expands, and the blood will be discharged from the blood chamber. 2 is also expanded, and blood flows back into the blood chamber 2 from the living body through the blood inflow tube 2a.After that, the same operation as described above is repeated to perform pumping, but for a long period of time. If a pinhole or crack occurs in blood chamber 2 due to pumping or a manufacturing defect in blood chamber 2, blood will leak into the saline during diastole of blood chamber 2 and enter saline chamber 3. Since the physiological saline in the transparent detection chamber 4a of the connected detection mechanism 4 is also dyed red, the optical sensor provided in the detection chamber 4a detects damage to the blood chamber 2 and stops pumping, as shown in the figure. The system uses a switching device to switch to a backup artificial heart pump. During this period, during the contraction phase of the blood chamber 2, physiological saline enters the blood through pinholes or cracks, but this poses no problem since physiological saline is harmless to living organisms. Additionally, if a pinhole or crack occurs in the saline chamber 3, air will be sucked into the saline during diastole and air bubbles will be generated. When detected, the same operation as above is performed.

Next, in the second embodiment shown in FIG.
By contracting the bellows-shaped portion 3a with air pressure, the blood chamber 2 also contracts, and blood is discharged into the living body through the blood discharge tube 2b.After blood discharge is completed, the housing 1
When the pressure inside is released, the physiological saline chamber 3 is expanded by the restoring force of the bellows-like portion 3a itself, and the blood chamber 2 is also expanded, so that blood from the living body enters the blood chamber 2 through the blood inflow tube 2a. The blood will be refluxed, and the same operation as described above will be repeated to perform pumping. In addition, in this embodiment, the saline chamber 3 is fixed to the housing 1 except for the bellows-like part 3a, so the amount of movement of contraction and expansion of the blood chamber 2 can be understood as the movement of the bellows-like part 3a.
If a distance sensor is provided on the distal end surface of the bellows-shaped portion 3a and the outer wall surface of the box body 1 as necessary, the inflow or discharge amount of blood can be accurately detected. In this embodiment, 6 is a drive device, and the drive device 6 includes a three-way solenoid valve 8 that switches the air supplied from the compressor 7, and a pressure controller 9 provided between the compressor 7 and the three-way solenoid valve 8. and a controller 10 that controls the switching timing of the three-way solenoid valve 8. Also, parts having the same configuration and operation as those of the first embodiment are given the same numbers and explanations are omitted. do.

In addition, the third embodiment shown in FIGS. 3 and 4 is
forming a cavity 3b in the saline chamber 3;
The blood chamber 2 is expanded and contracted by pressurizing or depressurizing the cavity 3b through the air supply/discharge hole 3c, and 13 is a distance sensor provided oppositely between the box 1 and the cavity 3b. The distance sensor 13 can detect the amount of expansion and contraction of the cavity 3b, and these points are different from the previous embodiments.

Furthermore, the fourth embodiment shown in FIG. 5 has the same basic configuration as the fifth embodiment, but differs from the third embodiment in that the hollow portion 3b is bellows-shaped. The advantage of making the cavity 3b bellows-shaped is that if it is a bag-shaped cavity, the absolute value of the distance will vary depending on the mounting position of the sensor, making adjustment extremely difficult. However, this disadvantage can be overcome, and the stroke volume can be accurately controlled.

(Effects of the Invention) As is clear from the above description, the present invention provides the following effects by encasing a blood chamber made of an elastic sac into a saline chamber made of an elastic sac filled with physiological saline. Even if a pinhole or crack occurs in the blood chamber, physiological saline may get into the blood chamber, but air will never get in, so there is no danger to life.
In addition, by supplying and exhausting air into the housing through the air supply and exhaust holes to pressurize or depressurize the saline in the saline chamber, a mechanical drive device is no longer required, making the device more compact. In addition, by providing a detection mechanism that detects air or blood intrusion into the physiological saline chamber, the detection mechanism can immediately detect the occurrence of pinholes or cracks in the blood chamber. Immediately stop pumping and switch to a backup artificial heart pump automatically or manually, and if there is a pinhole or crack in the saline chamber, remove any air bubbles that may have entered the saline. The sensing mechanism immediately detects a large leakage of saline and stops pumping before the saline chamber loses its ability to pressurize or depressurize the blood chamber.
Since it is only necessary to switch to a backup artificial heart pump, accidents that could lead to the death of living organisms can be accurately prevented.

Therefore, the present invention is of great benefit to the industry as it solves the problems of conventional artificial heart pumps.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a first embodiment of the present invention;
FIG. 2 is a cross-sectional view showing a second embodiment of the present invention, FIGS. 3 and 4 are longitudinal and cross-sectional views showing a third embodiment of the present invention, and FIG. 5 is a cross-sectional view showing a third embodiment of the present invention. FIG. 7 is a cross-sectional view showing a fourth example. 1...Housing, 1c, 3c...Air supply/discharge hole, 2...Blood chamber, 3...Physiological saline chamber, 4...Detection mechanism.

Claims (1)

[Claims] 1 In a pulsating artificial heart pump that circulates blood by repeatedly expanding and contracting a blood chamber 2 housed in a housing 1, a blood chamber 2 made of an elastic sac is disposed within the housing 1.
A physiological saline chamber 3 made of an elastic bladder enveloping the saline chamber 3 is provided.
It is characterized by being provided with air supply/discharge holes 1c and 3c for pressurizing or depressurizing the physiological saline inside the saline chamber 3, and also provided with a detection mechanism 4 for detecting that blood or air has entered the saline chamber 3. Artificial heart pump.