High-flow nasal cannula therapy in do-not-intubate patients with hypoxemic respiratory distress

Patients with do-not-intubate (DNI) status and respiratory failure are commonly treated with noninvasive ventilation (NIV). High-flow nasal cannula (HFNC) therapy supplies a high flow of heated and humidified oxygen that may provide an effective alternative to NIV. We assessed the efficacy of HFNC in DNI patients with hypoxemic respiratory distress.

We identified 50 DNI patients with hypoxemic respiratory distress who were admitted to a medical ICU and who received HFNC. We excluded patients with PaCO2 > 65 mm Hg and pH < 7.28. The primary end point was the need for escalation to NIV, as determined by the primary service. Mean changes in oxygen saturation and breathing frequency before and after HFNC were compared.

The subjects included 25 men and 25 women, mean age 73 years (range 27-96 y). Diagnoses (allowing multiple conditions) included pulmonary fibrosis (15), pneumonia (15), COPD (12), cancer (7), hematologic malignancy (7), and congestive heart failure (3). Hospital mortality was 60% (30/50). HFNC was initiated at a mean FIO2 of 0.67 (range 0.30-1.0) and flow of 42.6 L/min (range 30-60 L/min). Mean O2 saturations went from 89.1% to 94.7% (P < .001), and breathing frequency went from 30.6 breaths/min to 24.7 breaths/min (P < .001). Nine of the 50 subjects (18%) escalated to NIV, while 82% were maintained on HFNC. The median duration of HFNC was 30 hours (range 2-144 h).

HFNC can provide adequate oxygenation for many patients with hypoxemic respiratory failure and may be an alternative to NIV for DNI patients.