Efficacy and safety of high-flow nasal cannula oxygen therapy in patients with acute heart failure

Objectives. To evaluate the efficacy and safety of high-flow nasal cannula (HFNC) oxygen therapy in patients in acute respiratory failure due to acute heart failure (AHF) refractory to conventional oxygen therapy or noninvasive ventilation. Methods. Prospective observational study of patients with AHF and respiratory failure attended in an emergency department whose condition worsened after they were admitted to a short-stay unit, leading to use of HFNCs. Efficacy was assessed using a modified Borg dyspnea scale and oxygenation variables on discharge from the emergency department. Data were recorded after 24 hours on conventional oxygen therapy and after 60 and 120 minutes and 24 hours of HFNC therapy. Safety outcomes were the degree of patient comfort and the frequency of adverse events. Results. Forty-four patients with a mean (SD) age of 84 (7) years (75% women) were enrolled. Significant improvements were observed after HFNC oxygen therapy (baseline vs 60 and 120 minutes and baseline vs 24 hours) on clinical outcomes and oxygenation as well as decrease in respiratory frequency (P