Home > Lung Disease > Breakthroughs in Monitoring Asthma Get the Flash Player to see this player. Rate: (Click the stars to rate) Published on Nov 13, 2010 by Cleveland Clinic, Views: 3805 To use the nitrous oxide (NO) monitoring device, a patient breathes through a disposable filter attached to the equipment, then breathes out without taking the filter from the mouth. Following the exhalation, the device's advanced sensor technology automatically indicates how much NO is present in the patient's exhaled bre