A substantial number of patients with COVID-19 develops severe respiratory failure. Some patients present with a rapid decline in blood oxygen saturation, preceded only by mild symptoms. The immediate management of these patients include rapid sequence intubation (RSI) and mechanical ventilation. RSI in this situation however carries the risk of aggravated hypoxemia, with increased risk of cerebral or cardiac ischemia and death.

One main feature of COVID-19 is a mismatch between ventilated pulmonary alveoli and flow in adjacent pulmonary arterioles, also known as VQ-mismatch. Nitric Oxide (NO) physiologically relaxes arterial smooth muscles. Inhaled NO (INO) specifically relaxes arterioles in well ventilated areas of the lung, and thereby reduces VQ-mismatch. INO has in a number of studies been shown to increase oxygen saturation when administered through an endotracheal tube in mechanical ventilated patients.

In this trial we aim to study the effect of applying iNO and oxygen on a sealed face mask prior to RSI in patients with COVID-19 and hypoxia. The study is a randomized double-blinded parallel group design trial. Patients will be included pre-hospital by physicians in the Air Ambulance Department at Oslo University Hospital. Patients will be allocated to receive iNO/Oxygen or only Oxygen during treatment preceding RSI. The study protocol opens for inclusion also in emergency departments. Primary endpoint is change in oxygen saturation pre and post intervention. Secondary endpoints are hypoxemic episodes during RSI, change in blood pressure and mortality.

More information available at: www.ous-research.no/corona