Feasibility of non-invasive nitric oxide inhalation in acute hypoxic respiratory failure: potential role during the COVID-19 pandemic

Acute hypoxemic respiratory failure (ARF) is characterized by both lower arterial oxygen and carbon dioxide tensions in the blood. First line treatment for ARF includes oxygen therapy - intially admininstered non invasively using nasal prongs, high flow nasal cannulae or masks. Invasive mechancial ventilation (IMV) is usually reserved for patients who are unable to maintain their airway, those with worsening hypoxemia, or those who develop respiratory muscle fatigue and consequent hypercapnia. Inhaled nitric oxide (iNO) gas is known to improve oxygenation in patients with ARF by manipulating ventilation-perfusion matching. Addition of iNO may potentially alleviate the need for IMV in selected patients. This article demonstrates the feasibility of this technique based on our experience of patients with hypoxemic ARF. This technique may also be considered for patients with hypoxic ARF in setting of COVID-19.