Use High-Flow Nasal Cannula for Acute Respiratory Failure Patients in the Emergency Department: A Meta-Analysis Study.

Objective. To evaluate the efficacy of high-flow nasal cannula (HFNC) therapy compared with conventional oxygen therapy (COT) or noninvasive ventilation (NIV) for the treatment of acute respiratory failure (ARF) in emergency departments (EDs). Method. We comprehensively searched 3 databases (PubMed, EMBASE, and the Cochrane Library) for articles published from database inception to 12 July 2019. This study included only randomized controlled trials (RCTs) that were conducted in EDs and compared HFNC therapy with COT or NIV. The primary outcome was the intubation rate. The secondary outcomes were the mortality rate, intensive care unit (ICU) admission rate, ED discharge rate, need for escalation, length of ED stay, length of hospital stay, and patient dyspnea and comfort scores. Result. Five RCTs (n = 775) were included. There was a decreasing trend regarding the application of HFNC therapy and the intubation rate, but the difference was not statistically significant (RR, 0.53; 95% CI, 0.26-1.09; p=0.08; I-2 = 0%). We found that compared with patients who underwent COT, those who underwent HFNC therapy had a reduced need for escalation (RR, 0.41; 95% CI, 0.22-0.78; p=0.006; I-2 = 0%), reduced dyspnea scores (MD -0.82, 95% CI -1.45 to -0.18), and improved comfort (SMD -0.76 SD, 95% CI -1.01 to -0.51). Compared with the COT group, the HFNC therapy group had a similar mortality rate (RR, 1.25; 95% CI, 0.79-1.99; p=0.34; I-2 = 0%), ICU admission rate (RR, 1.11; 95% CI, 0.58-2.12; p=0.76; I-2 = 0%), ED discharge rate (RR, 1.04; 95% CI, 0.63-1.72; p=0.87; I-2 = 0%), length of ED stay (MD 1.66, 95% CI -0.95 to 4.27), and hospital stay (MD 0.9, 95% CI -2.06 to 3.87). Conclusion. Administering HFNC therapy in ARF patients in EDs might decrease the intubation rate compared with COT. In addition, it can decrease the need for escalation, decrease the patient's dyspnea level, and increase the patient's comfort level compared with COT.