What is the appropriate response when measured NO is above the set concentration during inhaled nitric oxide therapy?

Inhaled nitric oxide (iNO) therapy is commonly used in neonatology to treat conditions such as persistent pulmonary hypertension. During this therapy, it is crucial to monitor the concentration of nitric oxide being delivered to the patient. If the measured nitric oxide level is above the intended concentration, it indicates that the system is delivering more NO than expected, which can pose risks associated with excessive nitric oxide exposure.

Placing a one-way valve between the injector module and the humidifier is the appropriate response in this scenario. The purpose of the one-way valve is to prevent backflow or incorrect flow dynamics that may cause the concentration of NO to exceed the set point. This helps ensure that the gas is delivered correctly and protects both the delivery system and the patient.

Other options, while theoretically relevant to different system adjustments, do not directly address the immediate concern of excessive nitric oxide delivery. Increasing the frequency or flow rates, or turning the power off and on, may not adequately resolve the issue of high measured NO levels and could potentially complicate the delivery of therapy further. The one-way valve effectively mitigates this risk by ensuring the system operates as designed, maintaining safe and therapeutic levels of nitric oxide for the patient.