| abstract |
A respiratory therapy apparatus is disclosed that delivers a pulsed volume of NO containing therapeutic gas to a patient upon each inhalation of the patient. The NO delivery system includes certain functions to provide protection against the inadvertent formation of NO 2 through the reaction of NO and O 2 within the device itself. Since the formation of NO 2 is a time based reaction, the delivery system includes a timer that monitors the elapsed time the passes between pulses of a NO containing therapy gas to the patient. In the event that time exceeds a predetermined period, thereby raising the possibility that sufficient time has passed to potentially have toxic concentrations of NO 2 formed, the delivery device automatically itself delivers the pulse of NO containing gas to the patient and which clears the conduits, passageways and the like within the device to rid the device of any NO 2 that may have formed. As a further feature, the device also counts the number of successive times that the system activates itself and when that count exceeds a predetermined number, a fault condition is recognized and an appropriate alert is signaled to the user. |