Patent ID: 8408040
Filing Date: 2013-04-02
Classification: A61M,G01L

Abstract:
1. A method of calibrating a pressure measurement unit in an extracorporeal circuit system, the pressure measurement unit including a container having an air chamber provided with an air inlet-and-outlet port, a liquid chamber provided with a liquid inlet port and a liquid outlet port, and a flexible diaphragm that provides a partition between the air chamber and the liquid chamber and that deforms in accordance with a pressure difference between a pressure inside the air chamber and a pressure inside the liquid chamber; a first pressure measurer that is connected to the air inlet-and-outlet port of the container via a detachable connection; an upstream part and a downstream part of an extracorporeal circuit that are connected respectively to the liquid inlet port and the liquid outlet port of the liquid chamber; a closer that closes the upstream part and the downstream part of the extracorporeal circuit, respectively; second pressure measurer that measures pressure in an extracorporeal circuit part by the closer; a pressure adjusting pump provided in the extracorporeal circuit part closed by the closer or in a branch pipe branching from the extracorporeal circuit part; and a liquid sending pump provided in the extracorporeal circuit, the method being performed when a connection between the first pressure measurer and the air inlet-and-outlet port is disengaged after starting a pressure measurement for the extracorporeal circuit, the extracorporeal circuit system further including a detector and a controller, the method comprising: detecting, by the detector, the disengagement of the connection between the first pressure measurer and the air inlet-and-outlet port and transmitting information of the disengagement to the controller; stopping, by the controller, the liquid sending pump and closing the upstream part and the downstream part of the extracorporeal circuit using the closer; measuring, by the second pressure measurer, a pressure P driving, by the controller, the pressure adjusting pump and setting the pressure P after the setting, connecting, the first pressure measurer and the air inlet-and-outlet port to each other again.