Patent ID: 7810497
Filing Date: 2010-10-12
Classification: A61M,Y10S

Abstract:
1. A system for delivering a flow of breathing gas to an airway of a patient, the system comprising: a pressurizing flow module that generates a pressurized flow of breathing gas; a patient circuit coupled to the pressurizing flow module configured to communicate the flow of breathing gas to an airway of a patient; a sensor adapted to monitor a characteristic of a breathing pattern of the patient; and a controller that communicates with the sensor and is configured to identify a state of respiration of the patient based on information received from the sensor, and to effectuate patient treatment based on the state of respiration of the patient, wherein the controller is further configured such that (i) the state of respiration is identified as a high respiratory drive state responsive to the monitored characteristic exceeding an upper threshold value, (ii) the state of respiration is identified as a normal ventilation state responsive to the monitored characteristic being between the upper threshold value and a lower threshold value, and (iii) the state of respiration is identified as a low respiratory drive state responsive to the monitored characteristic being below the lower threshold value, wherein the controller is further configured such that effectuating patient treatment based on the state of respiration of the patient treatment includes increasing a fraction of inspired carbon dioxide responsive to the state of respiration being the high respiratory drive state and providing servo-ventilation responsive to the state of respiration being the low respiratory drive state, and wherein the controller is further configured such that the upper threshold value is decreased responsive to a change in a mean value of the monitored characteristic exceeding a predetermined limit, such that the upper threshold value is increased responsive to a frequency of carbon dioxide supported breaths supplied to the patient exceeding a predetermined frequency, and such that the lower threshold value is changed based on the monitored characteristic.