JP7795157B2 - IABP drive unit - Google Patents

Description

The present invention relates to an IABP drive device (abbreviation for IABP balloon drive device) that drives a balloon using the IABP (intra-aortic balloon pumping) method.

The balloon used in IABP (intra-aortic balloon pumping) is attached to a catheter, inserted into an artery in the patient's body, and placed in the aorta near the patient's heart. The IABP driver pumps by delivering a shuttle gas such as helium into the balloon via the catheter and repeatedly inflating and deflating the balloon in sync with the heartbeat. This increases blood flow in the coronary arteries of the heart in patients with heart disease such as myocardial infarction, heart failure, or cardiomyopathy, thereby increasing myocardial oxygen supply and reducing cardiac workload, thereby reducing oxygen consumption. Examples of such conventional IABP drivers are disclosed in Patent Documents 1 and 2 listed below.

The IABP drive devices described in Patent Documents 1 and 2 measure arterial blood pressure using a blood pressure sensor located outside the balloon and display the measured value. Helium gas is typically used as the shuttle gas for pumping the balloon. However, helium gas supplied to the balloon via a catheter can leak into the internal space of a blood pressure sensor, such as an optical sensor, located outside the balloon. Optical sensors have a diaphragm at the tip of a cylindrical section, the internal space of which is vacuum at the time of manufacture. Blood pressure is measured by measuring the amount of axial displacement of the diaphragm due to the pressure of blood in the artery. However, if helium gas leaks into the internal space of the optical sensor's cylindrical section, the diaphragm will be displaced away from the cylindrical section due to the helium gas pressure, resulting in a blood pressure that is lower than the actual blood pressure, resulting in inaccurate measurements. This phenomenon is called negative drift due to helium gas. Figure 7 shows how the pressure measured by the optical sensor becomes lower than the actual blood pressure over time and deviates from the actual blood pressure. Over time, negative drift (shown as "pressure drift" in Figure 7) causes the blood pressure measured by the optical sensor to be lower than the actual blood pressure. To prevent this problem, measures can be taken to prevent helium gas from flowing from the balloon into the optical sensor, but while this is effective to a certain extent, it is not possible to completely prevent the inflow of helium gas.

In the drive device for a balloon pump with an arterial pressure sensor described in Patent Document 1, the zero point of the blood pressure measurement by the arterial pressure sensor fixed to the tip of the balloon fluctuates over time, preventing accurate blood pressure measurement. To solve this problem, a pressure sensor is provided to measure the internal pressure of the balloon, and when a difference occurs between the blood pressure measured by the arterial pressure sensor and the blood pressure measured by the pressure sensor measuring the pressure inside the balloon, the zero point of the arterial pressure sensor is adjusted to eliminate this difference. Furthermore, in Patent Document 2 listed below, the shuttle gas delivered to the balloon is controlled to put the balloon in a semi-inflated state, the gas pressure inside the balloon is measured, and the measured pressure is used to calibrate the measurement by the blood pressure sensor connected to the balloon.

Patent No. 2902040 Patent No. 5361383

In the configurations disclosed in Patent Documents 1 and 2, blood pressure is measured using a pressure sensor that measures the pressure inside the balloon in order to calibrate the measurement value (zero adjustment/calibration) so that the operator can accurately grasp the blood pressure. Therefore, the balloon must be kept in a semi-inflated state. In this state, the IABP driver's original balloon pumping operation, which inflates and deflates the balloon in synchronization with the patient's heartbeat to reduce the patient's cardiac load, must be suspended (see Figure 2b of Patent Document 1, and paragraph 0019 and Figure 2 of Patent Document 2). In other words, according to Patent Documents 1 and 2, the IABP driver's original pumping operation is suspended during calibration. Therefore, during this suspension period, the patient's cardiac function cannot be supported, and there are concerns that this could adversely affect the patient's cardiac function, suppressing blood flow to the heart and increasing cardiac load. To address changes in the optical sensor over time, such calibration must be performed at regular intervals, in addition to when the IABP catheter is inserted, which necessitates the suspension of the pumping operation each time. Therefore, frequent calibration, which requires the balloon to be in a semi-inflated state, is undesirable, and should be performed at long intervals, such as every six hours. While this requires a long calibration interval, there is a problem in that the aforementioned negative drift occurs during this interval, i.e., while the IABP balloon is in operation, due to helium intrusion into the optical sensor. This negative drift can sometimes occur suddenly, causing a significant change midway between adjacent calibrations, i.e., during pumping operation, which is problematic.

In order to solve the problems of the prior art described above, the present invention calibrates the first pressure measured by a first pressure sensor disposed in a balloon by using a third pressure measured by a second pressure sensor that measures a second pressure, which is the pressure inside the balloon, and a third pressure measured by a third pressure sensor that is separate from the first pressure sensor. When it is determined that the first pressure calibrated using the second pressure is lower than the third pressure by more than a predetermined value, the first pressure is calibrated using the third pressure.

That is, according to the present invention, there is provided an IABP driving device for driving an IABP balloon having a first pressure sensor that measures a first pressure, the device comprising:
a second pressure sensor for measuring a second pressure, which is the internal pressure of the balloon;
a storage means capable of storing the first pressure, the second pressure, and the third pressure;
shuttle gas supply means for supplying a controlled amount of shuttle gas to the balloon to pump the balloon and for ceasing said pumping to place the balloon in a semi-inflated state;
a control means for controlling the shuttle gas supply means to perform the pumping and stop the pumping at predetermined time intervals to set the balloon in a semi-inflated state, and for controlling the storage means to store the first pressure and the second pressure when the balloon is in the semi-inflated state;
an adjustment means for comparing the first pressure stored in the storage means with the second pressure and adjusting the zero point of the first pressure sensor so that a first offset, which is the difference between the first pressure and the second pressure, is eliminated;
a first writing means for storing the first pressure immediately after the zero point of the first pressure sensor is adjusted by the adjusting means in the memory means;
means for receiving a blood pressure signal indicative of the third pressure measured by a third pressure sensor other than the first pressure sensor and the second pressure sensor during the pumping operation when the balloon is not in the semi-inflated state;
second writing means for storing the third pressure in the storage means;
a first determination means for comparing the first pressure and the third pressure stored in the storage means and determining whether the first pressure is smaller than the third pressure by more than a predetermined value;
a correcting means for calculating a second offset value which is the difference between the third pressure and the first pressure stored in the storage means when the first determining means determines that the first pressure is smaller than the third pressure by more than a predetermined value, and correcting the first pressure stored in the storage means using the calculated second offset value;
An IABP driver is provided having:

With this configuration, even if an undesirable negative drift suddenly occurs while the IABP balloon is being driven between adjacent calibrations, the correction means can use the third pressure to calibrate the first pressure, which had previously been calibrated using the second pressure and stored, to the correct pressure at that time. This eliminates the effects of the negative drift and enables the pressure value to be appropriately corrected without stopping pumping by the IABP drive device, thereby accurately supporting the function of the patient's heart and reducing the strain on the patient's heart.

According to the present invention, there is also provided an IABP driving device for driving an IABP balloon having a first pressure sensor that measures a first pressure, the device comprising:
a second pressure sensor for measuring a second pressure, which is the internal pressure of the balloon;
a storage means capable of storing the first pressure, the second pressure, and the third pressure;
shuttle gas supply means for supplying a controlled amount of shuttle gas to the balloon to pump the balloon and for ceasing said pumping to place the balloon in a semi-inflated state;
a control means for controlling the shuttle gas supply means to perform the pumping and stop the pumping at predetermined time intervals to set the balloon in a semi-inflated state, and for controlling the storage means to store the first pressure and the second pressure when the balloon is in the semi-inflated state;
an adjustment means for comparing the first pressure stored in the storage means with the second pressure and adjusting the zero point of the first pressure sensor so that a first offset, which is the difference between the first pressure and the second pressure, is eliminated;
a first writing means for storing the first pressure immediately after the zero point of the first pressure sensor is adjusted by the adjusting means in the memory means;
means for receiving a blood pressure signal indicative of the third pressure measured by a third pressure sensor other than the first pressure sensor and the second pressure sensor during the pumping operation when the balloon is not in the semi-inflated state;
second writing means for storing the third pressure in the storage means;
a first determination means for comparing the first pressure and the third pressure stored in the storage means and determining whether the first pressure is smaller than the third pressure by more than a predetermined value;
a second determination means for comparing the first pressure with the second pressure and determining whether the first pressure is lower than the second pressure by a second predetermined value or more;
a correcting means for calculating a second offset value which is the difference between the third pressure and the first pressure stored in the storage means, when the first determining means determines that the first pressure is lower than the third pressure by more than a predetermined value, and the second determining means determines that the first pressure is lower than the second pressure by more than the second predetermined value, and correcting the first pressure stored in the storage means using the calculated second offset value;
An IABP driver is provided having:

With this configuration, by adding conditions for the operation of the correction means, the correction means can be operated under desired conditions depending on the situation.

According to the present invention, there is also provided an IABP driving device for driving an IABP balloon having a first pressure sensor that measures a first pressure, the device comprising:
a second pressure sensor for measuring a second pressure, which is the internal pressure of the balloon;
a storage means capable of storing the first pressure, the second pressure, and the third pressure;
shuttle gas supply means for supplying a controlled amount of shuttle gas to the balloon to pump the balloon and for ceasing said pumping to place the balloon in a semi-inflated state;
a control means for controlling the shuttle gas supply means to perform the pumping and stop the pumping at predetermined time intervals to set the balloon in a semi-inflated state, and for controlling the storage means to store the first pressure and the second pressure when the balloon is in the semi-inflated state;
an adjustment means for comparing the first pressure stored in the storage means with the second pressure and adjusting the zero point of the first pressure sensor so that a first offset, which is the difference between the first pressure and the second pressure, is eliminated;
a first writing means for storing the first pressure immediately after the zero point of the first pressure sensor is adjusted by the adjusting means in the memory means;
means for receiving a blood pressure signal indicative of the third pressure measured by a third pressure sensor other than the first pressure sensor and the second pressure sensor during the pumping operation when the balloon is not in the semi-inflated state;
a first determination means for comparing the first pressure and the third pressure stored in the storage means and determining whether a difference between the first pressure and the third pressure is equal to or greater than a first predetermined value;
a second determination means for comparing the first pressure with the second pressure and determining whether the first pressure is lower than the second pressure by a second predetermined value or more;
a first calculation means for calculating a first difference which is a difference between a maximum value and a minimum value of the first pressure;
a second calculation means for calculating a second difference between the maximum and minimum values of the third pressure;
a third determination means for determining whether a value obtained by subtracting the first difference from the second difference is smaller than a third predetermined value;
a correcting means for calculating a second offset value which is the difference between the third pressure and the first pressure stored in the storage means, and correcting the first pressure stored in the storage means using the calculated second offset value, when the first determining means determines that the difference between the first pressure and the third pressure is equal to or greater than the first predetermined value, the second determining means determines that the first pressure is lower than the second pressure by equal to or greater than the second predetermined value, and the third determining means determines that the value obtained by subtracting the first difference from the second difference is smaller than a third predetermined value;
An IABP driver is provided having:

With this configuration, by adding conditions for the operation of the correction means, the correction means can be operated under desired conditions depending on the situation.

According to the present invention, there is also provided an IABP driving device for driving an IABP balloon having a first pressure sensor that measures a first pressure, the device comprising:
a second pressure sensor for measuring a second pressure, which is the internal pressure of the balloon;
a storage means capable of storing the first pressure, the second pressure, and the third pressure;
shuttle gas supply means for supplying a controlled amount of shuttle gas to the balloon to pump the balloon and for ceasing said pumping to place the balloon in a semi-inflated state;
a control means for controlling the shuttle gas supply means to perform the pumping and stop the pumping at predetermined time intervals to set the balloon in a semi-inflated state, and for controlling the storage means to store the first pressure and the second pressure when the balloon is in the semi-inflated state;
an adjustment means for comparing the first pressure stored in the storage means with the second pressure and adjusting the zero point of the first pressure sensor so that a first offset, which is the difference between the first pressure and the second pressure, is eliminated;
a first writing means for storing the first pressure immediately after the zero point of the first pressure sensor is adjusted by the adjusting means in the memory means;
means for receiving a blood pressure signal indicative of the third pressure measured by a third pressure sensor other than the first pressure sensor and the second pressure sensor during the pumping operation when the balloon is not in the semi-inflated state;
second writing means for storing the third pressure in the storage means;
a first determination means for comparing the first pressure and the third pressure stored in the storage means and determining whether the first pressure is smaller than the third pressure by more than a predetermined value;
a display means for calculating a second offset value, which is the difference between the third pressure and the first pressure stored in the storage means, when the first determination means determines that the first pressure is lower than the third pressure by more than a predetermined value, and displaying the calculated second offset value or the third pressure;
An IABP driver is provided having:

This configuration allows the physician to manually control the IABP driver by displaying the second offset value, allowing for detailed manual control separate from control by the correction means. As a result, it is possible to reduce the frequency of calibrations that stop pumping and eliminate the effects of negative drift, thereby enabling accurate support for the patient's cardiac function and reducing the strain on the patient's heart.

According to the present invention, there is also provided an IABP driving device for driving an IABP balloon having a first pressure sensor that measures a first pressure, the device comprising:
a second pressure sensor for measuring a second pressure, which is the internal pressure of the balloon;
a storage means capable of storing the first pressure, the second pressure, and the third pressure;
shuttle gas supply means for supplying a controlled amount of shuttle gas to the balloon to pump the balloon and for ceasing said pumping to place the balloon in a semi-inflated state;
a control means for controlling the shuttle gas supply means to perform the pumping and stop the pumping at predetermined time intervals to set the balloon in a semi-inflated state, and for controlling the storage means to store the first pressure and the second pressure when the balloon is in the semi-inflated state;
an adjustment means for comparing the first pressure stored in the storage means with the second pressure and adjusting the zero point of the first pressure sensor so that a first offset, which is the difference between the first pressure and the second pressure, is eliminated;
a first writing means for storing the first pressure immediately after the zero point of the first pressure sensor is adjusted by the adjusting means in the memory means;
means for receiving a blood pressure signal indicative of the third pressure measured by a third pressure sensor other than the first pressure sensor and the second pressure sensor during the pumping operation when the balloon is not in the semi-inflated state;
second writing means for storing the third pressure in the storage means;
a first determination means for comparing the first pressure and the third pressure stored in the storage means and determining whether the first pressure is smaller than the third pressure by more than a predetermined value;
a second determination means for comparing the first pressure with the second pressure and determining whether the first pressure is lower than the second pressure by a second predetermined value or more;
a display means for calculating a second offset value which is the difference between the third pressure and the first pressure stored in the storage means when the first determination means determines that the first pressure is lower than the third pressure by more than a predetermined value and the second determination means determines that the first pressure is lower than the second pressure by more than the second predetermined value, and for displaying the calculated second offset value or the third pressure;
An IABP driver is provided having:

With this configuration, by adding conditions for the operation of the display means, the display means can be operated under desired conditions depending on the situation.

According to the present invention, there is also provided an IABP driving device for driving an IABP balloon having a first pressure sensor that measures a first pressure, the device comprising:
a second pressure sensor for measuring a second pressure, which is the internal pressure of the balloon;
a storage means capable of storing the first pressure, the second pressure, and the third pressure;
shuttle gas supply means for supplying a controlled amount of shuttle gas to the balloon to pump the balloon and for ceasing said pumping to place the balloon in a semi-inflated state;
a control means for controlling the shuttle gas supply means to perform the pumping and stop the pumping at predetermined time intervals to set the balloon in a semi-inflated state, and for controlling the storage means to store the first pressure and the second pressure when the balloon is in the semi-inflated state;
an adjustment means for comparing the first pressure stored in the storage means with the second pressure and adjusting the zero point of the first pressure sensor so that a first offset, which is the difference between the first pressure and the second pressure, is eliminated;
a first writing means for storing the first pressure immediately after the zero point of the first pressure sensor is adjusted by the adjusting means in the memory means;
means for receiving a blood pressure signal indicative of the third pressure measured by a third pressure sensor other than the first pressure sensor and the second pressure sensor during the pumping operation when the balloon is not in the semi-inflated state;
second writing means for storing the third pressure in the storage means;
a first determination means for comparing the first pressure and the third pressure stored in the storage means and determining whether the first pressure is smaller than the third pressure by more than a predetermined value;
a second determination means for comparing the first pressure with the second pressure and determining whether the first pressure is lower than the second pressure by a second predetermined value or more;
a first calculation means for calculating a first difference which is a difference between a maximum value and a minimum value of the first pressure;
a second calculation means for calculating a second difference between the maximum and minimum values of the third pressure;
a third determination means for determining whether a value obtained by subtracting the first difference from the second difference is smaller than a third predetermined value;
a display means for calculating a second offset value which is the difference between the third pressure and the first pressure stored in the storage means, when the first determination means determines that the first pressure is lower than the third pressure by more than a predetermined value, the second determination means determines that the first pressure is lower than the second pressure by more than the second predetermined value, and the third determination means determines that a value obtained by subtracting the first difference from the second difference is lower than a third predetermined value; and
An IABP driver is provided having:

With this configuration, by adding conditions for the operation of the display means, the display means can be operated under desired conditions depending on the situation.

According to the present invention, there is also provided an IABP driving device for driving an IABP balloon having a first pressure sensor that measures a first pressure, the device comprising:
a second pressure sensor for measuring a second pressure, which is the internal pressure of the balloon;
a storage means capable of storing the first pressure, the second pressure, and the third pressure;
shuttle gas supply means for supplying a controlled amount of shuttle gas to the balloon to pump the balloon and for ceasing said pumping to place the balloon in a semi-inflated state;
a control means for controlling the shuttle gas supply means to perform the pumping and stop the pumping at predetermined time intervals to set the balloon in a semi-inflated state, and for controlling the storage means to store the first pressure and the second pressure when the balloon is in the semi-inflated state;
an adjustment means for comparing the first pressure stored in the storage means with the second pressure and adjusting the zero point of the first pressure sensor so that a first offset, which is the difference between the first pressure and the second pressure, is eliminated;
a first writing means for storing the first pressure immediately after the zero point of the first pressure sensor is adjusted by the adjusting means in the memory means;
means for receiving a blood pressure signal indicative of the third pressure measured by a third pressure sensor other than the first pressure sensor and the second pressure sensor during the pumping operation when the balloon is not in the semi-inflated state;
second writing means for storing the third pressure in the storage means;
a first determination means for comparing the first pressure and the third pressure stored in the storage means and determining whether the first pressure is smaller than the third pressure by more than a predetermined value;
a second storage means for calculating a second offset value, which is the difference between the third pressure and the first pressure stored in the storage means, when the first determination means determines that the first pressure is lower than the third pressure by more than a predetermined value, and for storing the calculated second offset value or the third pressure;
An IABP driver is provided having:

With this configuration, by storing the second offset, it is possible to grasp changes in the second offset during actual operation of the IABP drive device, allowing for more accurate operation of the IABP drive device thereafter. As a result, it is possible to reduce the frequency of calibrations that halt pumping, and it is also possible to eliminate the effects of negative drift that occurs during calibrations. This allows for accurate support of the patient's cardiac function and reduces the burden on the patient's heart.

According to the present invention, there is also provided an IABP driving device for driving an IABP balloon having a first pressure sensor that measures a first pressure, the device comprising:
a second pressure sensor for measuring a second pressure, which is the internal pressure of the balloon;
a storage means capable of storing the first pressure, the second pressure, and the third pressure;
shuttle gas supply means for supplying a controlled amount of shuttle gas to the balloon to pump the balloon and for ceasing said pumping to place the balloon in a semi-inflated state;
a control means for controlling the shuttle gas supply means to perform the pumping and stop the pumping at predetermined time intervals to set the balloon in a semi-inflated state, and for controlling the storage means to store the first pressure and the second pressure when the balloon is in the semi-inflated state;
an adjustment means for comparing the first pressure stored in the storage means with the second pressure and adjusting the zero point of the first pressure sensor so that a first offset, which is the difference between the first pressure and the second pressure, is eliminated;
a first writing means for storing the first pressure immediately after the zero point of the first pressure sensor is adjusted by the adjusting means in the memory means;
means for receiving a blood pressure signal indicative of the third pressure measured by a third pressure sensor other than the first pressure sensor and the second pressure sensor during the pumping operation when the balloon is not in the semi-inflated state;
second writing means for storing the third pressure in the storage means;
a first determination means for comparing the first pressure and the third pressure stored in the storage means and determining whether the first pressure is smaller than the third pressure by more than a predetermined value;
a second determination means for comparing the first pressure with the second pressure and determining whether the first pressure is lower than the second pressure by a second predetermined value or more;
a second storage means for calculating a second offset value which is the difference between the third pressure and the first pressure stored in the storage means when the first determination means determines that the first pressure is lower than the third pressure by more than a predetermined value and the second determination means determines that the first pressure is lower than the second pressure by more than the second predetermined value, and for storing the calculated second offset value or the third pressure;
An IABP driver is provided having:

With this configuration, by adding conditions for the operation of the storage means, the storage means can be operated under desired conditions.

According to the present invention, there is also provided an IABP driving device for driving an IABP balloon having a first pressure sensor that measures a first pressure, the device comprising:
a second pressure sensor for measuring a second pressure, which is the internal pressure of the balloon;
a storage means capable of storing the first pressure, the second pressure, and the third pressure;
shuttle gas supply means for supplying a controlled amount of shuttle gas to the balloon to pump the balloon and for ceasing said pumping to place the balloon in a semi-inflated state;
a control means for controlling the shuttle gas supply means to perform the pumping and stop the pumping at predetermined time intervals to set the balloon in a semi-inflated state, and for controlling the storage means to store the first pressure and the second pressure when the balloon is in the semi-inflated state;
an adjustment means for comparing the first pressure stored in the storage means with the second pressure and adjusting the zero point of the first pressure sensor so that a first offset, which is the difference between the first pressure and the second pressure, is eliminated;
a first writing means for storing the first pressure immediately after the zero point of the first pressure sensor is adjusted by the adjusting means in the memory means;
means for receiving a blood pressure signal indicative of the third pressure measured by a third pressure sensor other than the first pressure sensor and the second pressure sensor during the pumping operation when the balloon is not in the semi-inflated state;
second writing means for storing the third pressure in the storage means;
a first determination means for comparing the first pressure and the third pressure stored in the storage means and determining whether the first pressure is smaller than the third pressure by more than a predetermined value;
a second determination means for comparing the first pressure with the second pressure and determining whether the first pressure is lower than the second pressure by a second predetermined value or more;
a first calculation means for calculating a first difference which is a difference between a maximum value and a minimum value of the first pressure;
a second calculation means for calculating a second difference between the maximum and minimum values of the third pressure;
a third determination means for determining whether a value obtained by subtracting the first difference from the second difference is smaller than a third predetermined value ;
a second storage means for calculating a second offset value, which is the difference between the third pressure and the first pressure stored in the storage means, when the first determination means determines that the first pressure is lower than the third pressure by more than a predetermined value, the second determination means determines that the first pressure is lower than the second pressure by more than the second predetermined value, and the third determination means determines that a value obtained by subtracting the first difference from the second difference is lower than a third predetermined value; and
An IABP driver is provided having:

With this configuration, by adding conditions for the operation of the storage means, the storage means can be operated under desired conditions.

According to the present invention, there is also provided a method for calibrating, displaying, and storing measured blood pressure in an IABP drive device having shuttle gas supply means for supplying shuttle gas to an IABP balloon to pump the balloon and then stopping the pumping to keep the balloon in a semi-inflated state, the method comprising:
controlling the shuttle gas supply means to stop the pumping and place the balloon in a semi-inflated state;
When the balloon is in a semi-inflated state, reading and storing a first pressure measured by a first pressure sensor disposed outside the balloon and a second pressure measured by a second pressure sensor that measures the internal pressure of the balloon;
an adjustment step of comparing the stored first pressure with the stored second pressure, adjusting the zero point of the first pressure sensor so that a first offset, which is a difference between the first pressure and the second pressure, is eliminated, and immediately thereafter rewriting the already stored first pressure with the second pressure;
controlling the shuttle gas supply means to terminate the semi-inflated state of the balloon and resume pumping;
a time determination step of determining whether a predetermined time has elapsed since the previous zero point adjustment;
If the predetermined time has not elapsed, reading a third pressure indicating a blood pressure measured by a third pressure sensor other than the first pressure sensor and the second pressure sensor;
If the predetermined time has elapsed, returning to the step of semi-inflating the balloon;
and
a first determination step of comparing the first pressure with the third pressure and determining that the first pressure is lower than the third pressure by more than a predetermined value;
a second determination step of comparing the first pressure with the second pressure and determining that the first pressure is lower than the second pressure by more than a second predetermined value;
a third determination step of detecting a first difference, which is the difference between the maximum and minimum values of the first pressure; detecting a second difference, which is the difference between the maximum and minimum values of the third pressure; and determining whether the value obtained by subtracting the first difference from the second difference is smaller than a third predetermined value; calculating a second offset value, which is the difference between the third pressure and the first pressure, depending on the determination result of the first determination step, or depending on the determination results of the first and second determination steps , or depending on the determination results of the first to third determination steps; correcting the first pressure, which has already been rewritten and stored with the second pressure, using the calculated second offset value or the third pressure; displaying the second offset value or the third pressure; and storing the second offset value or the third pressure.

This configuration makes it possible to perform one or more of control, display, and storage depending on one or more of the three conditions in the three judgment steps, and to obtain one or more effects similar to those of the correction means, display means, and storage means in the IABP drive device described above.

The IABP drive device of the present invention described in any one of claims 1 to 3 has the above-mentioned configuration, so that the pressure value can be appropriately corrected by the correction means without stopping pumping by the IABP drive device, thereby achieving a corrected pressure value while accurately supporting the function of the patient's heart.

The IABP drive device of the present invention described in any one of claims 4 to 6 has the above-mentioned configuration, and by displaying the second offset value on the display means, a physician can manually control the IABP drive device, allowing for detailed manual response separate from corrections made by the correction means. As a result, it is possible to reduce the frequency of internal calibration, which stops pumping, and thereby obtain corrected pressure values while accurately supporting the function of the patient's heart.

The IABP driver of the present invention described in any one of claims 7 to 9 has the above-mentioned configuration, and by storing the second offset in the memory means, it is possible to grasp changes in the second offset during actual operation of the IABP driver, making subsequent operation of the IABP driver more accurate. As a result, it is possible to reduce the frequency of internal calibration, which stops pumping, and thereby obtain corrected pressure values while accurately supporting the function of the patient's heart.

The method for calibrating/displaying/storing measured blood pressure in an IABP drive device of the present invention described in claim 10 has the above-mentioned configuration, making it possible to perform one or more of control, display, and storage in accordance with one or more of the three conditions, thereby achieving one or more of the same effects as those achieved by the correction means, display means, and storage means in the IABP drive device described above.

4 is a flowchart showing a first operation of the IABP driving device according to the embodiment of the present invention. 2 is a flowchart showing the details of one step in the flowchart of FIG. 1; 10 is a flowchart showing a second operation in the embodiment of the IABP driving device of the present invention. 10 is a flowchart showing a third operation of the IABP driving device according to the embodiment of the present invention. 1 is a perspective view showing a main body of an embodiment of an IABP drive device of the present invention; FIG. 1 is a block diagram of an embodiment of an IABP drive device of the present invention. FIG. 1 is a diagram showing changes in blood pressure measurements over time, illustrating the operation of a conventional IABP drive device.

Preferred embodiments of the present invention will now be described with reference to the drawings.
5 is a perspective view showing the main body of an embodiment of the IABP drive device of the present invention. The IABP drive device 10 is placed near a patient and is configured so that a doctor can operate the operation unit 12 and visually check the blood pressure values and electrocardiogram displayed on the display unit 14. The appearance of the IABP drive device 10 is similar to that of conventional devices.

Figure 6 is a block diagram of an embodiment of the IABP drive device of the present invention. The IABP drive device 10 includes an operation unit 12, a display unit 14, a shuttle gas supply source 16, a control unit 18, an interface 20, and a memory unit 22. The shuttle gas supply source 16, which constitutes the shuttle gas supply means, supplies shuttle gas to the interior of the IABP balloon 28 via a catheter 24. The shuttle gas supply source 16 includes a positive pressure source, a negative pressure source, and a gas source such as helium gas (not shown). In response to a control signal from the control unit 18, the shuttle gas supply source 16 controls the flow rate of the shuttle gas supplied to the interior of the balloon 28, thereby repeatedly inflating and deflating the balloon 28. Specifically, the shuttle gas supply source 16 can pump the balloon 28 or temporarily halt pumping to place the balloon in a semi-inflated state; these operations are controlled by the control unit 18. The control signal generated by the control unit 18 is generated using a predetermined register that functions as at least the first memory means within the control unit 18. An optical sensor 30 is disposed on the exterior of the balloon 28.

The optical sensor 30 measures the first pressure P1, which is the blood pressure in an artery (not shown), and constitutes a first pressure sensor. One end of the optical fiber 26 is connected to the optical sensor 30, and the other end of the optical fiber 26 is connected to the interface 20. In this example, the optical sensor 30 measures the first pressure P1, which is the blood pressure near the balloon 28, but the sensor for measuring the first pressure P1 is not limited to an optical sensor. The catheter 24, balloon 28, and optical sensor 30 shown in FIG. 6 are not components of the IABP drive device 10 itself; rather, the catheter 24 is connected to the IABP drive device 10, shuttle gas is supplied inside the balloon 28, and the optical sensor 30 measures the blood pressure in the artery in which the balloon 28 is located.

A pressure sensor 32 is connected to the catheter 24. The pressure sensor 32 measures a second pressure P2, which is the internal pressure of the balloon 28, and the output signal is supplied to the interface 20, which constitutes the receiving means. The pressure sensor 32 constitutes the second pressure sensor 32. In this example, the second pressure sensor 32 is provided inside the IABP drive device 10, but it may also be provided externally. In the IABP drive device, a sensor (not shown) is attached to the patient to obtain the patient's electrocardiogram, and the output signal of this sensor is input to the IABP drive device, and the electrocardiogram is displayed on the display unit 14 as necessary.

Pressure sensor 34, separate from first pressure sensor 30 and second pressure sensor 32, measures third pressure P3, which is the blood pressure at a predetermined location on the patient's body. This pressure sensor 34 constitutes the third pressure sensor 34. For example, a pressure transducer for measuring blood pressure, used for connecting to a bedside monitor, can be used as the third pressure sensor 34. That is, third pressure sensor 34 is used to minimize the frequency of calibrations in which balloon 28 is placed in a semi-inflated state and used as a blood pressure sensor, and to reduce the effects of negative drift that may occur during operation of the IABP balloon between adjacent calibrations. It is desirable for this pressure sensor, separate from first pressure sensor 30 and second pressure sensor 32, to be able to measure actual blood pressure as accurately as possible. Like first pressure sensor 30, third pressure sensor 34 is not a component of the IABP drive device 10 itself.

In accordance with instructions from the operator input via the operation unit 12, the control unit 18 controls the shuttle gas supply source 16 to appropriately regulate the flow rate of shuttle gas supplied to the balloon 28 via the catheter 24, so that the balloon pumps (repeatedly expands and contracts) in synchronization with the patient's heartbeat. To perform this control, the control unit 18 includes a CPU (central processing unit) (not shown), a RAM (temporary storage memory), and a ROM (read-only memory) that stores programs for the CPU's operation. In addition to controlling the inflation and deflation of the balloon, the control unit 18 also controls the display of necessary information on the display unit 14 and the storage of specified information in the memory unit 22. In other words, the control unit 18 constitutes control means, but also constitutes storage means, adjustment means, correction means, first to third determination means, first and second calculation means, and first and second writing means.

FIG. 1 is a flowchart showing the first operation of an embodiment of the IABP drive device of the present invention. That is, it shows the operation of the CPU in the control unit 18 in FIG. 6. The flow in FIG. 1 starts when the power switch of the IABP drive device 10 is turned on and an instruction to start pumping is given. First, in step S1, it is determined whether a calibration instruction has been received from the physician operating the IABP drive device 10. The physician can use the operation unit 12 of the IABP drive device 10 to input an instruction to perform calibration when calibration is deemed necessary. If an instruction to perform calibration has been received, the control unit 18 indicates that an instruction to perform calibration has been received, for example, by setting a corresponding flag. If an instruction to perform calibration has not been received, the determination in step S1 is NO, and step S1 is repeated. If an instruction to calibrate has been received, the determination in step S1 is YES, and the process proceeds to step S2, where the pumping of the balloon 28 that had been performed up until that point is temporarily stopped and the balloon 28 is placed in a semi-inflated state.

That is, the control unit 18 controls the shuttle gas supply source 16 to control the flow rate of shuttle gas supplied to the balloon 28 via the catheter 24, thereby placing the balloon 28 in a semi-inflated state. Since the internal pressure of the semi-inflated balloon 28 is considered to be equal to the ambient pressure (i.e., the arterial blood pressure), the internal pressure of the semi-inflated balloon 28, i.e., the measured pressure P2 of the second pressure sensor 32, can be considered to indicate blood pressure. While step S1 determines whether a calibration command has been issued, this is not limiting; step S1 can also be determined to be YES every time a predetermined time has elapsed on a predetermined timer. Furthermore, step S1 can also determine both whether a calibration command has been issued and whether a predetermined time has elapsed. In this case, if step S1 returns YES in response to a calibration command, the physician can manually initiate calibration when deemed necessary. If step S1 returns YES after a predetermined time has elapsed, calibration can be automatically initiated after the predetermined time has elapsed, regardless of the physician's judgment.

In the next step S3, the first and second pressures P1 and P2 are read as measured pressures. These pressures P1 and P2 are stored in a predetermined register, which functions as the first storage means within the control unit 18. In addition to the predetermined register, they can also be stored in the storage unit 22. Because these measured pressures P1, P2, and the third measured pressure P3 (described later) repeatedly rise and fall over time, the time averages of the measured pressures P1, P2, and P3 input from the interface 20 are calculated. These time averages are used in the following steps, except for the cases where maximum and minimum values are to be obtained. Instead of time averages, medians or other statistically processed values, which are values obtained by statistically processing values that change over time, can also be used for these pressures P1, P2, and P3. In other words, the pressures P1, P2, and P3 used in the following steps are average values, such as statistically processed values, rather than instantaneous values, except for the cases where maximum and minimum values are to be obtained. Although not shown in the figure, pumping continues to be suspended in step S2 until the measured pressures P1 and P2 are stored in step S3, and the balloon 28 remains in a semi-inflated state.

In the next step S4, a first offset value OF1, which is the difference between the second pressure P2 and the first pressure P1, is calculated. In the next step S5, the first offset value OF1 is used to perform zero-point adjustment of the first pressure sensor 30. In other words, the first pressure P1 measured by the first pressure sensor 30 is calibrated and replaced with the second pressure P2 measured by the second pressure sensor 32, and this is stored in a predetermined register functioning as a first storage means within the control unit 18. Note that this can also be stored in the storage unit 22, in addition to the predetermined register. From a hardware perspective, the zero-point adjustment of the first pressure sensor 30 in step S5 constitutes an adjustment means. When the zero-point adjustment in step S5 is completed, the first pressure P1 immediately after the zero-point adjustment is stored. In other words, the first pressure P1 read and stored in step S3 while the balloon 28 is in a semi-inflated state is overwritten and rewritten with the first pressure P1 immediately after the zero-point adjustment. From a hardware perspective, this rewriting constitutes the first writing means. After the rewriting, the balloon 28, which was set to a semi-inflated state in step S2, returns to normal pumping operation from the semi-inflated state. Next, in step S6, it is determined whether a predetermined time has passed since the previous zero point adjustment. The predetermined time can be several hours, for example, about six hours. This elapsed time can be determined using a software timer with a set time, or by comparing the time of the first zero point adjustment with the current time. If the predetermined time has not passed, the determination result in step S6 will be NO, and the program will proceed to step S7.

On the other hand, once the predetermined time has elapsed, the determination in step S6 becomes YES, and the process returns to step S2, where zero point adjustment is performed again in step S5 via steps S2 to S4. That is, if the predetermined time in step S6 is, for example, six hours, calibration through zero point adjustment is repeated every six hours. Note that while six hours is given as an example of the predetermined time in step S6, the balloon could be semi-inflated once 30 minutes after the start of operation in the early stages after the IABP drive device 10 begins operation, once every hour thereafter until six hours have elapsed, and once every six hours after six hours have elapsed. That is, the predetermined time in step S6 is not fixed, but could be variable depending on the time elapsed since the IABP drive device 10 began operation.

If the predetermined time has not elapsed, i.e., if the determination result in step S6 is NO, the measured pressure (third pressure) P3 is read in step S7 and stored in a predetermined register that functions as the first storage means within the control unit 18. Note that instead of storing it in the predetermined register, it can also be stored in the storage unit 22. From a hardware perspective, storing the third pressure P3 in step S7 constitutes a second writing means. Next, in step S8, the first pressure P1 is subtracted from the third pressure P3, and it is determined whether the difference is greater than a first predetermined value T1. In other words, it is determined whether the first pressure P1 is less than the third pressure P3 by a predetermined value. The first predetermined value T1 can be, for example, 5 mmHg. As an example, if the first pressure P1 is 45 mmHg and the third pressure P3 is 55 mmHg, then P3 - P1 = 10 mmHg. If T1 is 5 mmHg, then 10 mmHg > 5 mmHg, meaning that the first pressure P1 is smaller than the third pressure P3 by more than the predetermined value. Note that, regardless of the above example, the first predetermined value T1 can be set larger or smaller as needed. If it is set to 0, and P3 > P1, step S8 will return YES.

If the determination result in step S8 is NO, the process returns to step S7. If the determination result is YES, the process proceeds to step S9, where the first pressure P1 is subtracted from the third pressure P3 to obtain the second offset value OF2 as the calculation result. Next, in step S10, the first pressure P1 is corrected using the second offset value OF2. That is, the first pressure P1 is corrected to a value obtained by adding the second offset value OF2 to the first pressure P1 after it was changed and stored through calibration in step S5. Specifically, this is the same as using the third pressure P3 obtained by the third pressure sensor 34 in place of the first pressure P1 (in other words, rewriting the first pressure with the third pressure). Therefore, the first pressure P1 stored in the predetermined register functioning as the first storage means within the control unit 18 or in the storage unit 22 is overwritten with the third pressure P3.

Here, the first pressure P1 before being overwritten by the third pressure P3 is not the value read in step S3, but the value zero-adjusted and replaced with the second pressure P2 in step S5. In other words, the first pressure P1 after being changed and stored through calibration in step S5 is discarded and replaced with the third pressure P3. The correction to the value obtained by adding the second offset value OF2 in step S5, or the rewriting of the first pressure with the third pressure P3, constitutes a correction means in hardware terms. In the next step S11, a determination is made as to whether or not a termination command has been received from the physician. Similar to the calibration command described above, a termination command is an instruction input by the physician using the operation unit 12 of the IABP drive device 10 to terminate the operation of the IABP drive device 10. If a termination command is received, the control unit 18 indicates that a termination command has been received, for example, by setting a corresponding flag. If a termination command is not received, the determination in step S11 is NO, and the process returns to step S6. If it is determined that an instruction to end has been given, step S11 becomes YES, and the flow in Figure 1 ends. In step S11, it is determined whether or not an instruction to end has been given from the doctor, but this is not limiting, and the result of the determination in step S11 can also be YES every time a predetermined time has elapsed on a predetermined timer.

When returning from step S11 to step S6, if the predetermined time has not elapsed in step S6, steps S7 to S11 are executed. If step S8d returns YES, the first pressure P1 stored up to that point is discarded and replaced with the third pressure P3 in steps S9 and S10. Also, if step S6 determines that the predetermined time has elapsed, the process returns to step S2, and steps S2 to S5 are executed. Therefore, the value rewritten with the third pressure P3 in step S11 will be used until another negative drift occurs before the next calibration using a semi-inflated balloon, causing the first pressure P1 to be discarded again and replaced with the third pressure P3, or until the next calibration using a semi-inflated balloon.

Figure 2 is a flowchart showing step S10 in Figure 1 in detail. In step S10a, the above-mentioned correction is performed using the second offset value OF2. In the next step S10b, the second offset value OF2 is displayed on the display unit 14. The physician operating the IABP driver 10 can use the second offset value OF2 displayed on the display unit 14 to operate the operation unit 12 to issue calibration instructions or perform other controls as needed. In step S10c, the second offset value OF2 is stored in the memory unit 22. The memory unit 22, which constitutes the storage means, can be a semiconductor RAM or a hard disk. Storing the second offset value OF2 allows the change in the second offset value OF2 during actual operation of the IABP driver 10 to be understood, allowing subsequent operation of the IABP driver 10 to be more accurate, thereby reducing the frequency of calibrations that require pumping to be stopped. Note that the above correction, display, and storage are not limited to being based on the second offset value OF2, but may also be based on the third pressure P3, and display and storage can target both the second offset value OF2 and the third pressure P3.

In the flowchart of FIG. 2, the three processing steps S10a, S10b, and S10c are shown to be executed sequentially. However, these three steps do not necessarily have to be executed in the order of the flowchart of FIG. 2. All three steps can be executed in any order, or only one of these three steps, or two of these steps can be executed in any order. In other words, the "Modify/Display/Store" in step S10 in FIG. 1 means to execute one or more of these three operations. If two or more are executed, any two or three of them can be executed in any order. Furthermore, if the execution of step S10 determines that the IABP drive unit 10 is correctly calibrating the pressure P1, the frequency of zero-point adjustments with pumping temporarily stopped, i.e., the execution of steps S2 to S5, can be reduced. To achieve this, the predetermined time in step S6 can be set to a longer time.

Figure 3 is a flowchart showing a second operation of an embodiment of the IABP drive device 10 of the present invention. In Figure 3, steps that are the same as those in Figure 1 are designated by the same step numbers, and their explanations are omitted. The flowchart in Figure 3 differs from the flowchart in Figure 1 only in the following respect: a new step S8a has been added between steps S8 and S9 in Figure 1. In step S8a, the first pressure P1 and the second pressure P2 are compared to determine whether the difference between the two is greater than a second predetermined value T2. The second predetermined value T2 can be set to, for example, 20 mmHg. If the determination result in step S8a is NO, the process returns to step S7. If the determination result in step S8a is YES, the process proceeds to step S9, where the same processing as in Figure 1 is performed.

FIG. 4 is a flowchart illustrating a third operation of an embodiment of the IABP drive device 10 of the present invention. In FIG. 4, steps identical to those in FIG. 3 are designated by the same step numbers and will not be described further. The flowchart in FIG. 4 differs from the flowchart in FIG. 3 only in the following respect: new steps S8b, S8c, and S8d have been added between steps S8a and S9 in FIG. 3. In step S8b, a first difference P1diff between the maximum value P1max and minimum value P1min of the first pressure P1 is calculated. In step S8c, a second difference P3diff between the maximum value P3max and minimum value P3min of the third pressure P3 is calculated. In the next step S8d, the first difference P1diff is subtracted from the second difference P3diff, and it is determined whether the difference is less than a third predetermined value T3. The third predetermined value T3 may be, for example, 10 mmHg. If the determination result in step S8d is NO, the process returns to step S7. If the result of the determination in step 8d is YES, the process proceeds to step S9, where the same processing as in Figures 1 and 3 is carried out.

As shown in the flowcharts of Figures 1, 3, and 4 described above, if the answer is NO in step S11, the process returns to step S1, and is repeated until the answer in step S11 becomes YES. In other words, after the instruction to calibrate is issued, steps S2 to S10 are executed until the instruction to end is issued, and in step S10, control is performed using the second offset value OF2, the second offset value OF2 is displayed on the display unit 14, and the second offset value OF2 is stored in the memory unit 22, thereby achieving the effects described above.

In the above-described embodiments, the present invention has been described as an IABP drive device or a method for controlling an IABP drive device, but it can also be understood as a program for instructing the operation of the CPU, which is the main part of the control unit 18 of the IABP drive device 10. In other words, the present invention can be understood as a program for causing a computer to execute the method for calibrating/displaying/storing measured blood pressure in an IABP drive device as set forth in claim 10.

The IABP drive device of the present invention has the above-described configuration, making it possible to minimize the time that the balloon inflation and deflation operation, which is the IABP drive device's primary operation, is suspended. This allows for accurate support of the patient's cardiac function and reduces the burden on the patient's heart. Therefore, the device can be used in a variety of industries, including the medical device industry, which develops and manufactures IABP drive devices, and the medical industry, which uses IABP drive devices.

10 IABP driving device 12 Operation unit 14 Display unit (display means)
16 Shuttle gas supply source (shuttle gas supply means)
18 Control unit (storage means, control means, adjustment means, correction means, first to third judgment means, first and second calculation means, first and second writing means)
20 Interface (receiving means)
22 Storage unit (storage means)
24 Catheter 26 Optical fiber 28 IABP balloon 30 Optical sensor (first pressure sensor)
32 Second pressure sensor 34 Third pressure sensor

Claims (10)

1. An IABP drive device for driving an IABP balloon having a first pressure sensor that measures a first pressure,
a second pressure sensor for measuring a second pressure, which is the internal pressure of the balloon;
a storage means capable of storing the first pressure, the second pressure, and the third pressure;
shuttle gas supply means for supplying a controlled amount of shuttle gas to the balloon to pump the balloon and for ceasing said pumping to place the balloon in a semi-inflated state;
a control means for controlling the shuttle gas supply means to perform the pumping and stop the pumping at predetermined time intervals to set the balloon in a semi-inflated state, and for controlling the storage means to store the first pressure and the second pressure when the balloon is in the semi-inflated state;
an adjustment means for comparing the first pressure stored in the storage means with the second pressure and adjusting the zero point of the first pressure sensor so that a first offset, which is the difference between the first pressure and the second pressure, is eliminated;
a first writing means for storing the first pressure immediately after the zero point of the first pressure sensor is adjusted by the adjusting means in the memory means;
means for receiving a blood pressure signal indicative of the third pressure measured by a third pressure sensor other than the first pressure sensor and the second pressure sensor during the pumping operation when the balloon is not in the semi-inflated state;
second writing means for storing the third pressure in the storage means;
a first determination means for comparing the first pressure and the third pressure stored in the storage means and determining whether the first pressure is smaller than the third pressure by more than a predetermined value;
a correcting means for calculating a second offset value which is the difference between the third pressure and the first pressure stored in the storage means when the first determining means determines that the first pressure is smaller than the third pressure by more than a predetermined value, and correcting the first pressure stored in the storage means using the calculated second offset value;
An IABP drive device having: 1. An IABP drive device for driving an IABP balloon having a first pressure sensor that measures a first pressure,
a second pressure sensor for measuring a second pressure, which is the internal pressure of the balloon;
a storage means capable of storing the first pressure, the second pressure, and the third pressure;
shuttle gas supply means for supplying a controlled amount of shuttle gas to the balloon to pump the balloon and for ceasing said pumping to place the balloon in a semi-inflated state;
a control means for controlling the shuttle gas supply means to perform the pumping and stop the pumping at predetermined time intervals to set the balloon in a semi-inflated state, and for controlling the storage means to store the first pressure and the second pressure when the balloon is in the semi-inflated state;
an adjustment means for comparing the first pressure stored in the storage means with the second pressure and adjusting the zero point of the first pressure sensor so that a first offset, which is the difference between the first pressure and the second pressure, is eliminated;
a first writing means for storing the first pressure immediately after the zero point of the first pressure sensor is adjusted by the adjusting means in the memory means;
means for receiving a blood pressure signal indicative of the third pressure measured by a third pressure sensor other than the first pressure sensor and the second pressure sensor during the pumping operation when the balloon is not in the semi-inflated state;
second writing means for storing the third pressure in the storage means;
a first determination means for comparing the first pressure and the third pressure stored in the storage means and determining whether the first pressure is smaller than the third pressure by more than a predetermined value;
a second determination means for comparing the first pressure with the second pressure and determining whether the first pressure is lower than the second pressure by a second predetermined value or more;
a correcting means for calculating a second offset value which is the difference between the third pressure and the first pressure stored in the storage means, when the first determining means determines that the first pressure is lower than the third pressure by more than a predetermined value, and the second determining means determines that the first pressure is lower than the second pressure by more than the second predetermined value, and correcting the first pressure stored in the storage means using the calculated second offset value;
An IABP drive device having: 1. An IABP drive device for driving an IABP balloon having a first pressure sensor that measures a first pressure,
a second pressure sensor for measuring a second pressure, which is the internal pressure of the balloon;
a storage means capable of storing the first pressure, the second pressure, and the third pressure;
shuttle gas supply means for supplying a controlled amount of shuttle gas to the balloon to pump the balloon and for ceasing said pumping to place the balloon in a semi-inflated state;
a control means for controlling the shuttle gas supply means to perform the pumping and stop the pumping at predetermined time intervals to set the balloon in a semi-inflated state, and for controlling the storage means to store the first pressure and the second pressure when the balloon is in the semi-inflated state;
an adjustment means for comparing the first pressure stored in the storage means with the second pressure and adjusting the zero point of the first pressure sensor so that a first offset, which is the difference between the first pressure and the second pressure, is eliminated;
a first writing means for storing the first pressure immediately after the zero point of the first pressure sensor is adjusted by the adjusting means in the memory means;
means for receiving a blood pressure signal indicative of the third pressure measured by a third pressure sensor other than the first pressure sensor and the second pressure sensor during the pumping operation when the balloon is not in the semi-inflated state;
second writing means for storing the third pressure in the storage means;
a first determination means for comparing the first pressure and the third pressure stored in the storage means and determining whether the first pressure is smaller than the third pressure by more than a predetermined value;
a second determination means for comparing the first pressure with the second pressure and determining whether the first pressure is lower than the second pressure by a second predetermined value or more;
a first calculation means for calculating a first difference which is a difference between a maximum value and a minimum value of the first pressure;
a second calculation means for calculating a second difference between the maximum and minimum values of the third pressure;
a third determination means for determining whether a value obtained by subtracting the first difference from the second difference is smaller than a third predetermined value;
a correcting means for calculating a second offset value which is the difference between the third pressure and the first pressure stored in the storage means, when the first determining means determines that the first pressure is lower than the third pressure by more than a predetermined value, the second determining means determines that the first pressure is lower than the second pressure by more than the second predetermined value, and the third determining means determines that a value obtained by subtracting the first difference from the second difference is lower than a third predetermined value; and
An IABP drive device having: 1. An IABP drive device for driving an IABP balloon having a first pressure sensor that measures a first pressure,
a second pressure sensor for measuring a second pressure, which is the internal pressure of the balloon;
a storage means capable of storing the first pressure, the second pressure, and the third pressure;
shuttle gas supply means for supplying a controlled amount of shuttle gas to the balloon to pump the balloon and for ceasing said pumping to place the balloon in a semi-inflated state;
a control means for controlling the shuttle gas supply means to perform the pumping and stop the pumping at predetermined time intervals to set the balloon in a semi-inflated state, and for controlling the storage means to store the first pressure and the second pressure when the balloon is in the semi-inflated state;
an adjustment means for comparing the first pressure stored in the storage means with the second pressure and adjusting the zero point of the first pressure sensor so that a first offset, which is the difference between the first pressure and the second pressure, is eliminated;
a first writing means for storing the first pressure immediately after the zero point of the first pressure sensor is adjusted by the adjusting means in the memory means;
means for receiving a blood pressure signal indicative of the third pressure measured by a third pressure sensor other than the first pressure sensor and the second pressure sensor during the pumping operation when the balloon is not in the semi-inflated state;
second writing means for storing the third pressure in the storage means;
a first determination means for comparing the first pressure and the third pressure stored in the storage means and determining whether the first pressure is smaller than the third pressure by more than a predetermined value;
a display means for calculating a second offset value, which is the difference between the third pressure and the first pressure stored in the storage means, when the first determination means determines that the first pressure is lower than the third pressure by more than a predetermined value, and displaying the calculated second offset value or the third pressure;
An IABP drive device having: 1. An IABP drive device for driving an IABP balloon having a first pressure sensor that measures a first pressure,
a second pressure sensor for measuring a second pressure, which is the internal pressure of the balloon;
a storage means capable of storing the first pressure, the second pressure, and the third pressure;
shuttle gas supply means for supplying a controlled amount of shuttle gas to the balloon to pump the balloon and for ceasing said pumping to place the balloon in a semi-inflated state;
a control means for controlling the shuttle gas supply means to perform the pumping and stop the pumping at predetermined time intervals to set the balloon in a semi-inflated state, and for controlling the storage means to store the first pressure and the second pressure when the balloon is in the semi-inflated state;
an adjustment means for comparing the first pressure stored in the storage means with the second pressure and adjusting the zero point of the first pressure sensor so that a first offset, which is the difference between the first pressure and the second pressure, is eliminated;
a first writing means for storing the first pressure immediately after the zero point of the first pressure sensor is adjusted by the adjusting means in the memory means;
means for receiving a blood pressure signal indicative of the third pressure measured by a third pressure sensor other than the first pressure sensor and the second pressure sensor during the pumping operation when the balloon is not in the semi-inflated state;
second writing means for storing the third pressure in the storage means;
a first determination means for comparing the first pressure and the third pressure stored in the storage means and determining whether the first pressure is smaller than the third pressure by more than a predetermined value;
a second determination means for comparing the first pressure with the second pressure and determining whether the first pressure is lower than the second pressure by a second predetermined value or more;
a display means for calculating a second offset value which is the difference between the third pressure and the first pressure stored in the storage means when the first determination means determines that the first pressure is lower than the third pressure by more than a predetermined value and the second determination means determines that the first pressure is lower than the second pressure by more than the second predetermined value, and for displaying the calculated second offset value or the third pressure;
An IABP drive device having: 1. An IABP drive device for driving an IABP balloon having a first pressure sensor that measures a first pressure,
a second pressure sensor for measuring a second pressure, which is the internal pressure of the balloon;
a storage means capable of storing the first pressure, the second pressure, and the third pressure;
shuttle gas supply means for supplying a controlled amount of shuttle gas to the balloon to pump the balloon and for ceasing said pumping to place the balloon in a semi-inflated state;
a control means for controlling the shuttle gas supply means to perform the pumping and stop the pumping at predetermined time intervals to set the balloon in a semi-inflated state, and for controlling the storage means to store the first pressure and the second pressure when the balloon is in the semi-inflated state;
an adjustment means for comparing the first pressure stored in the storage means with the second pressure and adjusting the zero point of the first pressure sensor so that a first offset, which is the difference between the first pressure and the second pressure, is eliminated;
a first writing means for storing the first pressure immediately after the zero point of the first pressure sensor is adjusted by the adjusting means in the memory means;
means for receiving a blood pressure signal indicative of the third pressure measured by a third pressure sensor other than the first pressure sensor and the second pressure sensor during the pumping operation when the balloon is not in the semi-inflated state;
second writing means for storing the third pressure in the storage means;
a first determination means for comparing the first pressure and the third pressure stored in the storage means and determining whether the first pressure is smaller than the third pressure by more than a predetermined value;
a second determination means for comparing the first pressure with the second pressure and determining whether the first pressure is lower than the second pressure by a second predetermined value or more;
a first calculation means for calculating a first difference which is a difference between a maximum value and a minimum value of the first pressure;
a second calculation means for calculating a second difference between the maximum and minimum values of the third pressure;
a third determination means for determining whether a value obtained by subtracting the first difference from the second difference is smaller than a third predetermined value;
a display means for calculating a second offset value which is the difference between the third pressure and the first pressure stored in the storage means, when the first determination means determines that the first pressure is lower than the third pressure by more than a predetermined value, the second determination means determines that the first pressure is lower than the second pressure by more than the second predetermined value, and the third determination means determines that a value obtained by subtracting the first difference from the second difference is lower than a third predetermined value; and
An IABP drive device having: 1. An IABP drive device for driving an IABP balloon having a first pressure sensor that measures a first pressure,
a second pressure sensor for measuring a second pressure, which is the internal pressure of the balloon;
a storage means capable of storing the first pressure, the second pressure, and the third pressure;
shuttle gas supply means for supplying a controlled amount of shuttle gas to the balloon to pump the balloon and for ceasing said pumping to place the balloon in a semi-inflated state;
a control means for controlling the shuttle gas supply means to perform the pumping and stop the pumping at predetermined time intervals to set the balloon in a semi-inflated state, and for controlling the storage means to store the first pressure and the second pressure when the balloon is in the semi-inflated state;
an adjustment means for comparing the first pressure stored in the storage means with the second pressure and adjusting the zero point of the first pressure sensor so that a first offset, which is the difference between the first pressure and the second pressure, is eliminated;
a first writing means for storing the first pressure immediately after the zero point of the first pressure sensor is adjusted by the adjusting means in the memory means;
means for receiving a blood pressure signal indicative of the third pressure measured by a third pressure sensor other than the first pressure sensor and the second pressure sensor during the pumping operation when the balloon is not in the semi-inflated state;
second writing means for storing the third pressure in the storage means;
a first determination means for comparing the first pressure and the third pressure stored in the storage means and determining whether the first pressure is smaller than the third pressure by more than a predetermined value;
a second storage means for calculating a second offset value, which is the difference between the third pressure and the first pressure stored in the storage means, when the first determination means determines that the first pressure is lower than the third pressure by more than a predetermined value, and for storing the calculated second offset value or the third pressure;
An IABP drive device having: 1. An IABP drive device for driving an IABP balloon having a first pressure sensor that measures a first pressure,
a second pressure sensor for measuring a second pressure, which is the internal pressure of the balloon;
a storage means capable of storing the first pressure, the second pressure, and the third pressure;
a shuttle gas supply means for supplying an appropriate amount of shuttle gas to the balloon to pump the balloon;
a control means for controlling the shuttle gas supply means;
an adjusting means for controlling the shuttle gas supply means so that the balloon is in a semi-inflated state at predetermined time intervals, comparing the first pressure with the second pressure when the balloon is in the semi-inflated state, and adjusting the zero point of the first pressure sensor so that a first offset, which is the difference between the first and second pressures, is eliminated;
a first writing means for storing the first pressure immediately after the zero point of the first pressure sensor is adjusted by the adjusting means in the memory means;
means for receiving a blood pressure signal indicative of the third pressure measured by a third pressure sensor other than the first pressure sensor and the second pressure sensor during a pumping operation when the balloon is not in the semi-inflated state;
second writing means for storing the third pressure in the storage means;
a first determination means for comparing the first pressure and the third pressure stored in the storage means and determining whether the first pressure is smaller than the third pressure by more than a predetermined value;
a second determination means for comparing the first pressure with the second pressure and determining whether the first pressure is lower than the second pressure by a second predetermined value or more;
a second storage means for calculating a second offset value which is the difference between the third pressure and the first pressure stored in the storage means when the first determination means determines that the first pressure is lower than the third pressure by more than a predetermined value and the second determination means determines that the first pressure is lower than the second pressure by more than the second predetermined value, and for storing the calculated second offset value or the third pressure;
An IABP drive device having: 1. An IABP drive device for driving an IABP balloon having a first pressure sensor that measures a first pressure,
a second pressure sensor for measuring a second pressure, which is the internal pressure of the balloon;
a storage means capable of storing the first pressure, the second pressure, and the third pressure;
shuttle gas supply means for supplying a controlled amount of shuttle gas to the balloon to pump the balloon and for ceasing said pumping to place the balloon in a semi-inflated state;
a control means for controlling the shuttle gas supply means to perform the pumping and stop the pumping at predetermined time intervals to set the balloon in a semi-inflated state, and for controlling the storage means to store the first pressure and the second pressure when the balloon is in the semi-inflated state;
an adjustment means for comparing the first pressure stored in the storage means with the second pressure and adjusting the zero point of the first pressure sensor so that a first offset, which is the difference between the first pressure and the second pressure, is eliminated;
a first writing means for storing the first pressure immediately after the zero point of the first pressure sensor is adjusted by the adjusting means in the memory means;
means for receiving a blood pressure signal indicative of the third pressure measured by a third pressure sensor other than the first pressure sensor and the second pressure sensor during the pumping operation when the balloon is not in the semi-inflated state;
second writing means for storing the third pressure in the storage means;
a first determination means for comparing the first pressure and the third pressure stored in the storage means and determining whether the first pressure is smaller than the third pressure by more than a predetermined value;
a second determination means for comparing the first pressure with the second pressure and determining whether the first pressure is lower than the second pressure by a second predetermined value or more;
a first calculation means for calculating a first difference which is a difference between a maximum value and a minimum value of the first pressure;
a second calculation means for calculating a second difference between the maximum and minimum values of the third pressure;
a third determination means for determining whether a value obtained by subtracting the first difference from the second difference is smaller than a third predetermined value ;
a second storage means for calculating a second offset value, which is the difference between the third pressure and the first pressure stored in the storage means, when the first determination means determines that the first pressure is lower than the third pressure by more than a predetermined value, the second determination means determines that the first pressure is lower than the second pressure by more than the second predetermined value, and the third determination means determines that a value obtained by subtracting the first difference from the second difference is lower than a third predetermined value; and
An IABP drive device having: 1. A method for calibrating, displaying, and storing measured blood pressure in an IABP drive device having shuttle gas supply means for supplying shuttle gas to an IABP balloon to pump the balloon, and then stopping the pumping to keep the balloon in a semi-inflated state, comprising:
controlling the shuttle gas supply means to stop the pumping and place the balloon in a semi-inflated state;
When the balloon is in a semi-inflated state, reading and storing a first pressure measured by a first pressure sensor disposed outside the balloon and a second pressure measured by a second pressure sensor that measures the internal pressure of the balloon;
an adjustment step of comparing the stored first pressure with the stored second pressure, adjusting the zero point of the first pressure sensor so that a first offset, which is a difference between the first pressure and the second pressure, is eliminated, and immediately thereafter rewriting the already stored first pressure with the second pressure;
controlling the shuttle gas supply means to terminate the semi-inflated state of the balloon and resume pumping;
a time determination step of determining whether a predetermined time has elapsed since the previous zero point adjustment;
If the predetermined time has not elapsed, reading a third pressure indicating a blood pressure measured by a third pressure sensor other than the first pressure sensor and the second pressure sensor;
If the predetermined time has elapsed, returning to the step of semi-inflating the balloon;
and
a first determination step of comparing the first pressure with the third pressure and determining that the first pressure is lower than the third pressure by more than a predetermined value;
a second determination step of comparing the first pressure with the second pressure and determining that the first pressure is lower than the second pressure by more than a second predetermined value;
a third determination step for determining whether a value obtained by subtracting the first difference from the third difference is smaller than a third predetermined value ; a second offset value for calculating ...