Blood purification device

Abstract

To provide a blood purification device that can accurately determine whether a venipuncture has been performed correctly in a patient. [Solution] The blood purification device 1 comprises a blood purifier 3 capable of purifying blood, a blood circuit 2 having an arterial blood circuit 21 and a venous blood circuit 22, an impedance measuring unit 5 having an oscillator 53 that applies an AC voltage between an arterial electrode 51 provided on the arterial blood circuit 21 and a venous electrode 52 provided on the venous blood circuit 22, and capable of measuring the frequency characteristics of the impedance between the arterial electrode 51 and the venous electrode 52, and a puncture determination unit 72 that determines whether the patient has been punctured normally based on the measured impedance frequency characteristics, and further comprises a voltage control unit 70 that controls the amplitude of the AC voltage applied by the oscillator 53 so that the amplitude of the AC current that flows when the AC voltage is applied from the oscillator 53 is greater than or equal to a preset lower threshold.

Claims

1. A blood purifier capable of purifying blood, A blood circuit for extracorporeal circulation of the patient's blood has an arterial blood circuit with an arterial puncture needle attached to its tip and its base connected to the blood purifier, and a venous blood circuit with a venous puncture needle attached to its tip and its base connected to the blood purifier, An impedance measuring unit having an oscillator that applies an AC voltage between the arterial electrode provided in the arterial blood circuit and the venous electrode provided in the venous blood circuit, and capable of measuring the frequency characteristics of the impedance between the arterial electrode and the venous electrode, The system includes a puncture determination unit that determines whether the patient has been properly punctured based on the frequency characteristics of the impedance measured by the impedance measurement unit, Furthermore, the system includes a voltage control unit that controls the amplitude of the AC voltage applied by the oscillator so that the amplitude of the AC current flowing when an AC voltage is applied from the oscillator is equal to or greater than a preset lower threshold. Blood purification device.

2. The voltage control unit stops the application of the AC voltage by the oscillator when the amplitude of the AC voltage applied by the oscillator exceeds a preset upper voltage threshold. The blood purification device according to claim 1.

3. The voltage control unit controls the amplitude of the AC voltage applied by the oscillator so that the amplitude of the AC current is less than or equal to a preset upper limit. The blood purification device according to claim 1.

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