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Respiratory Support in the Emergency Department: An Updated Systematic Review and Meta-Analysis

O'Donnell J, Fenn R

Worldviews on evidence-based nursing, 2026

2,158 participants

Abstract

Background: An estimated 20% of emergency department (ED) patients require respiratory support (RS). Evidence suggests that nasal high flow (NHF) reduces RS need.

Aims: This is an update of a published review comparing NHF to non-invasive ventilation (NIV) or to conventional oxygen therapy (COT) in adult ED patients.

Method: This updated systematic review (SR) and meta-analysis (MA) methods reflect the Cochrane Collaboration's methodology. The search of six databases was first completed in July 2023 and then repeated in November 2025. Databases were searched for randomized controlled trials (RCTs) comparing NHF to COT or NIV in the ED. Three summary estimates were reported: (1) need to escalate care, (2) mortality, and (3) adverse events (AEs).

Results: The updated search identified three new studies, bringing the total to 21 eligible RCTs (n = 2158). One of the six MA conclusions was statistically significant. Compared with COT, NHF showed no SS difference in the risk of escalation (RR 0.65; 95% CI [0.41, 1.04]; p = 0.07), mortality (RR 1.05; 95% CI [0.74, 1.51]; p = 0.77), and AE (RR was 0.98; 95% CI [0.6, 1.6]; p = 0.94) outcomes were found. Compared with NIV, NHF increased the risk of escalation by 86% (RR 1.86; 95% CI [1.26, 2.75]; p = 0.001), but mortality risk was not SS (RR 1.33; 95% CI [0.86, 2.06]; p = 0.20).

Linking evidence to action: Evidence suggests NHF therapy may be an alternative to COT in managing RS in EDs. While NHF may not be as effective as NIV at…

How strong is the evidence?

Evidence Hub reads this as a meta-analysis, done in people. Its evidence level is 1 of 5 (Highest · pooled evidence). Pooled evidence from several studies sits at the top of the evidence pyramid. Reported size: 2,158 participants or records.

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