Pause control of nitric oxide therapy

A system for the delivery of nitric oxide for therapy to a patient by providing a flow of nitric oxide (NO) to a patient, said system having a supply of a NO containing gas, a central processing unit (CPU), and a user input for establishing the desired therapy to the patient, said system further having a pause control system comprising a shut-off valve having an open position where the flow of NO is provided to the patient at a predetermined concentration and a closed position where the flow of NO is stopped, said shut-off valve being operable between said closed and said open positions by a signal from said CPU, means on said user input operable by a user to initiate a pause in the delivery of NO to the patient, said user input providing a signal to said CPU to change said shut-off valve to the closed position, said CPU further having a timing means effective to turn said shut-off valve back to the open position after the passage of a predetermined period of time whereby the predetermined concentration of NO is reestablished to the patient, said system further having a monitoring system to determine the concentration of certain gases flowing to the patient, and an alarm system to cause an alarm when the monitored concentrations exceed limits established by the user, and wherein said CPU further disables said alarm system during the time said shut-off valve is in said closed position and reestablishes said same alarm limits established by the user when said shut-off valve is turned back to said open position.