Patent ID: 7591267

Claim:
A breathing circuit for a patient, the breathing circuit comprising: an inspiration limb providing breathing gases for supply to the patient; an expiration limb receiving breathing gases from the patient; means for circulating breathing gases in the breathing circuit to supply breathing gases to the patient and to receive breathing gases expired from the patient; a CO 2 absorber positioned in the breathing circuit between the expiration limb and the inspiration limb for removing CO 2 from the breathing gases expired by the patient; a heat exchanger positioned downstream from the CO 2 absorber for reducing the temperature of the breathing gases and removing moisture from the breathing gases after the breathing gases exit the CO 2 absorber and prior to delivery of the breathing gases to the inspiration limb; and a sump separate from the heat exchanger and mounted to the heat exchanger, the sump positioned below the heat exchanger to collect moisture removed from the breathing gases as the breathing gases pass through the heat exchanger, the sump including a drainage valve, wherein the heat exchanger comprises: a plurality of vertically oriented inflow tubes passing through an open interior of the heat exchanger, each inflow tube having a first end in fluid communication with the CO 2 absorber and a second end in fluid communication with the sump; a plurality of vertically oriented outflow tubes passing through the open interior of the heat exchanger, each outflow tube having a first end in fluid communication with the sump and a second end in fluid communication with the inspiration limb, wherein the temperature within the open interior of the heat exchanger is below the temperature of the breathing gases in both the inflow and outflow tubes to reduce the temperature of the breathing gases as the breathing gases pass through the inflow and outflow tubes.