High-Flow Nasal Cannula versus Conventional Oxygen Therapy for Patients with Acute Respiratory Failure in the Emergency Department: A Randomized Controlled Trial.

Background: To compare the efficacy of a high-flow nasal cannula (HFNC) versus conventional oxygen therapy (COT) in the treatment of patients admitted to the emergency department (ED) for acute respiratory failure (ARF).

Materials and methods: In this prospective randomized clinical trial, 66 patients aged 18 years or older who presented with ARF to the ED were enrolled and assigned into two equal groups to receive either COT or HFNC for 60 minutes. The primary outcome was the intubation rates. The secondary outcomes were the effect of intervention on oxygenation, ICU admission rate, and effect on physiologic variables.

Results: 33 patients were treated in each group. The main causes of ARF were chronic obstructive pulmonary disease (COPD), pneumonia, and asthma. The need for intubation was higher in COT than in HFNC (42.5% vs 12.1%, P = 0.004). Patients with HFNC had a higher dyspnea improvement than those treated with COT (93.9% vs 63.7%, P = 0.002). They also showed greater improvement in oxygen saturation (increase in SpO₂ was 8.3% vs. -0.5, difference 8.8% (6.8 to 10.9)), and in respiratory rate (decrease 3.0 beats/min vs 0.2 beats/min, differences 2.8(0.8 to 4.6)). The ICU admission was higher in the COT group (51.5 vs 15.2, P=0.002).

Conclusion: HFNC reduced the need for intubation and ICU admission in the patients presenting to the ED with ARF compared with COT. In addition, HFNC was associated with a greater reduction in RR and improvement in SpO₂ compared with COT.