Abstract: A pressure monitoring apparatus (1) for monitoring pressure of a liquid (4) in a vessel (2) comprises a housing (3) within which an airtight gas chamber (6) is formed. A pressure sensor (8) is located in the housing (3) monitors the pressure of a gas in the gas chamber (6). A conduit (12) having a communicating bore (16) of total length Lt communicates the gas chamber (6) with the vessel (2). As the pressure of the liquid in the vessel (2) increases, a liquid/gas interface meniscus (20) travels along a working length Lw of the communicating bore (16) from the second end (15) thus increasing the pressure in the gas chamber (6) to the pressure of the liquid, which is monitored by the pressure sensor (8). The total length Lt of the conduit (12) is greater than the working length Lw of the conduit (12) to avoid the liquid/gas interface meniscus (20) reaching the first end (14) of the communicating bore (16).

Abstract: A pressure monitoring apparatus (1) for monitoring pressure of a liquid (4) in a vessel (2) comprises a housing (3) within which an airtight gas chamber (6) is formed. A pressure sensor (8) is located in the housing (3) monitors the pressure of a gas in the gas chamber (6). A conduit (12) having a communicating bore (16) of total length Lt communicates the gas chamber (6) with the vessel (2). As the pressure of the liquid in the vessel (2) increases, a liquid/gas interface meniscus (20) travels along a working length Lw of the communicating bore (16) from the second end (15) thus increasing the pressure in the gas chamber (6) to the pressure of the liquid, which is monitored by the pressure sensor (8). The total length Lt of the conduit (12) is greater than the working length Lw of the conduit (12) to avoid the liquid/gas interface meniscus (20) reaching the first end (14) of the communicating bore (16).

Abstract: A system for insufflating a vessel in a human or animal body, such as the rectum (2) comprises a compressed air vessel (12) from which air inflating medium is passed through a pressure regulator (13), a flow control valve (16) and an inflating conduit (14) which extends into the rectum (2) through a bore (9) in an endoscope (8). A first pressure sensor (15) located in a leading end (17) of the endoscope (8) monitors the air pressure directly in the rectum (2). A second pressure sensor (23) on a carrier element (25) extends through the bore (9) of the endoscope (8) into the colon (4) for monitoring pressure in the colon (4). A third pressure sensor (30) adjacent a point (37) of a needle (32) introduced into the abdominal cavity (3), through which air which may leak into the abdominal cavity (3) is exhausted, monitors pressure in the abdominal cavity (3).