Patent ID: 8166802

Claim:
A chest drainage apparatus, comprising: an enclosure with a transparent window; a union for connection to an end of a tube designed to be connected, at another end, to the chest cavity of a patient in order to convey exuded liquids and air losses; a collection vessel arranged to receive the exuded liquids from the tube connected to the union; a duct ( 4 ) arranged to receive and convey the air losses from the tube connected to the union, the duct having an outlet which conveys the air losses; and a device for displaying and measuring air losses, the device in communication with the duct, comprising, the device located within the enclosure at the transparent window, the device comprising i) a chamber ( 5 ) arranged at the transparent window, the chamber holding a liquid ( 6 ), the chamber having a bottom ( 5 a ) and an outlet section ( 4 a ) at the bottom of the chamber, the outlet section connected to the outlet of the duct, the outlet section conveying the air losses to the chamber, the conveyed air losses passing through the liquid into a top portion of the chamber, ii) a bell ( 7 ) within the chamber, the bell in a position above the outlet section, the bell having a lower edge in contact with the bottom of the chamber, a lower area of the bell immersed in the liquid and containing a volume of the liquid, iii) a constantly open air outflow port ( 8 ) located in the lower area of the bell immersed in the liquid, the constantly open air outflow port spaced apart from the outlet section of the chamber, iv) an air outflow port ( 9 ) located above the outlet section of the chamber, v) a manually operable, opening and closure element ( 10 ) located in the air outflow port, the conveyed air losses passing through the air outflow port into the top portion of the chamber when the opening and closure element is in an open position, the conveyed air losses not passing through the air outflow port into the top portion of the chamber when the opening and closure element is in a closed position, and with the opening and closure element in the closed position the air outflow port is closed causing an action emptying the liquid from the bell through the constantly open air outflow port, a measurement of a flow-rate of the loss of air being determined by a time required to empty the volume of the liquid from the bell.