What is the purpose of Exhaled Nitric Oxide (FEno) Testing?

Exhaled Nitric Oxide (FEno) Testing is specifically utilized to assess the level of inflammation in the airways, particularly in patients with asthma. It measures the concentration of nitric oxide in exhaled breath, which is a byproduct of inflammation. This testing is valuable in evaluating how well a patient is responding to anti-inflammatory treatments, such as corticosteroids. Increased levels of exhaled nitric oxide indicate ongoing inflammation, guiding clinicians in adjusting treatment plans to better control a patient's asthma or other related respiratory conditions.

The other options do not align with the primary function of FEno Testing. For example, measuring blood oxygen levels pertains to arterial blood gas testing or pulse oximetry, while monitoring hydration levels typically involves assessing urine concentration or changes in body weight. Assessing lung capacity, on the other hand, is achieved through pulmonary function tests like spirometry rather than through exhaled nitric oxide measurement. Thus, the purpose of FEno Testing firmly supports the response to anti-inflammatory treatment.