Rapid anesthesia emergence system using closed-loop PCO.sub.2 control
AssigneeThe Brigham and Women's Hospital, Inc.
InventorDan Raemer
Life of this patent
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Abstract
A system is disclosed for rapidly restoring ventilatory drive to an anesthetized patient after surgery. The end-expired carbon dioxide partial pressure is used as feedback to determine the amount of CO.sub.2 to be added to the inspired breathing mixture of the patient's breathing circuit. The CO.sub.2 added to the patient's breathing circuit increases CO.sub.2 within the blood stream to a level sufficient to stimulate the central ventilatory center in the brain, thereby rapidly restoring ventilatory drive to the patient.
Claims21
A method for restoring ventilatory drive to an anesthesized patient, the method comprising:
- (a) measuring the end-tidal value of the respiratory PCO.sub.2 of the patient;
- (b) comparing said measurement of the end-tidal value of the respiratory PCO.sub.2 with a reference value as feedback to determine the amount of CO.sub.2 to be added to a patient's breathing circuit;
- and
- (c) adding said amount of CO.sub.2 to the inspired mixture of the patient's breathing circuit.
A device for restoring ventilatory drive to an anesthetized subject comprising:
- (a) means for determining the partial pressure of CO.sub.2 in the blood stream of a subject;
- (b) feedback means utilizing said determination of the partial pressure of CO.sub.2 in the blood stream of a subject;
- and
- (c) means for adding CO.sub.2 into the breathing circuit as determined by the feedback means;
- (d) wherein said feedback means differentiates between the expired peak value of CO.sub.2 from the inspired peak value of CO.sub.2 which may be produced by the addition of CO.sub.2 to the breathing mixture.
A device for restoring ventilatory drive to an anesthetized subject comprising:
- (a) means for determining the partial pressure of CO.sub.2 in the blood stream of a subject;
- (b) feedback means utilizing said determination of the partial pressure of CO.sub.2 in the blood stream of a subject;
- and
- (c) means for adding CO.sub.2 into the breathing circuit as determined by the feedback means;
- (d) means for measuring the inspired PCO.sub.2 of a subject and second feedback means for comparing said measured inspired PCO.sub.2 with a reference value for determining the amount of CO.sub.2 to be added into the breathing circuit.
A device for restoring ventilatory drive to an anesthetized subject comprising:
- (a) means for determining the partial pressure of CO.sub.2 in the blood stream of a subject;
- (b) feedback means utilizing said determination of the partial pressure of CO.sub.2 in the blood stream of a subject;
- and
- (c) means for adding CO.sub.2 into the breathing circuit as determined by the feedback means;
- (d) means for comparing said added CO.sub.2 with a reference value for determining the amount of CO.sub.2 to be added into the breathing circuit.
Dependencies are inferred from the claim text.