High Flow Nasal Cannula Oxygen vs. Conventional Oxygen Therapy and Noninvasive Ventilation in Emergency Department Patients: A Systematic Review and Meta-Analysis.

BACKGROUND:Acute respiratory failure (ARF) is a common cause of presentation to the Emergency Department (ED). High flow nasal cannula (HFNC) has been introduced as an alternative way to administer oxygen. OBJECTIVES:We performed a systematic review and meta-analysis of randomized controlled trials (RCTs) comparing HFNC with conventional oxygen therapy (COT) and noninvasive ventilation (NIV) exclusively in the ED setting. METHODS:Inclusion criteria were: RCTs on adults with ARF admitted to the ED, investigating HFNC vs. COT or other modes of ventilation. Trials that compared HFNC support outside the ED, were published as an abstract, or nonrandomized were excluded. RESULTS:Four RCTs comparing HFNC with COT and one HFNC to NIV met the criteria. Overall, 775 patients were included. The meta-analysis of the studies comparing HFNC and COT showed no differences in intubation requirement, treatment failure, hospitalization, or mortality. Intolerance was significantly higher with HFNC (risk ratio 6.81 95% confidence interval 1.18-39.19; p = 0.03). In the only available RCT comparing HFNC with NIV, no difference was found for intubation rate, treatment failure, tolerance, and dyspnea. CONCLUSIONS:We did not find any benefit of HFNC compared with COT and NIV in terms of intubation requirement, treatment failure, hospitalization, and mortality; COT was better tolerated.