Patent ID: 6672300
Filing Date: 2004-01-06
Classification: A61M

Abstract:
A respiration assistor for use in an anesthesia breathing system for providing in-phase respiratory assistance to a spontaneously breathing patient and which comprises:a) a first gas supply passage, b) a first connecting means for connecting the first gas supply passage in circuit with a patient side of the breathing system and, hence, to a first gas supply of anesthetic gas, c) a gas flow detector located in the first gas supply passage and arranged to detect flow of the anesthetic gas induced by spontaneous inspiratory breathing by the patient, d) an electrically activatable pressure booster connected in circuit with the first gas supply passage and arranged when actuated to deliver the anesthetic gas to the patient under a pressure sufficient to assist the spontaneous inspiratory breathing of the patient whereby the end-expired CO2 level of the patient is maintained at or near a normal physiological level, the pressure booster being blower that permits substantially free flow of the inspired anesthetic gas therethrough when the pressure booster is not activated whereby the spontaneously breathing patient draws the anesthetic gas through the pressure booster in the event that the respiration assistor malfunctions, e) a gas delivery conduit for delivering pressurized anesthetic gas to the patient from the pressure booster, f) an electrically actuatable expiratory valve, g) a gas exhaust conduit for carrying expired gas from the patient to the expiratory valve, h) a second connecting means for connecting a second gas supply in circuit with the first gas supply in circuit with the first gas supply passage, and i) an electrical control circuit arranged to: i. effect activation of the pressure booster and closure of the expiratory valve upon detection of inspired gas flow through the gas flow detector, and ii. effect deactivation of the pressure booster and opening of the expiratory valve in the absence of inspired gas flow through the gas flow detector.