A novel non-invasive index of oxygenation and prediction of outcomes for patients on high-flow nasal cannula: a pilot study.

Predicting success of a therapy in acute respiratory failure is clinically important. The FOx index (high-flow rate × FiO2 )/SpO2 was retrospectively applied to 70 patients who required high-flow nasal prongs for hypoxaemic and hypercapnic respiratory failure. The FOx index could predict between success and failure of high-flow nasal prongs at 6 hours, using non-invasive markers. This adds to the clinician's toolbox in managing respiratory failure and represents important proof of concept for a prospective study.