Patent ID: 8187466

Claim:
An air-release device for allowing air to be released from a liquid in extracorporeal circuitry, the air-release device comprising: an elongate chamber having a bottom region and a top region and a fluid entry port and fluid exit port at or near the bottom region; a vent structure at or near the top region of the elongate chamber, the vent structure comprising a first porous layer; and a second porous layer comprising a porous material capable of swelling when moistened such that the vent structure can inhibit liquid from escaping the air-release device during use; and a microporous membrane adjacent the vent structure at or near the top region of the elongate chamber such that liquid can be passed through the elongate chamber from the entry port to the exit port so as to at least partially fill the elongate chamber with the liquid while air exits the chamber via the microporous membrane and the vent structure, wherein the first porous layer is disposed between the micro-porous membrane and the second porous layer.