The effect of high-flow nasal cannula in reducing the mortality and the rate of endotracheal intubation when used before mechanical ventilation compared with conventional oxygen therapy and noninvasive positive pressure ventilation. A systematic review and meta-analysis

Am J Emerg Med. 2018 Feb;36(2):226-233. doi: 10.1016/j.ajem.2017.07.083. Epub 2017 Jul 28.


Background: The effects of high flow nasal cannula (HFNC) on adult patients when used before mechanical ventilation (MV) are unclear. We aimed to determine the effectiveness of HFNC when used before MV by comparison to conventional oxygen therapy (COT) and noninvasive positive pressure ventilation (NIPPV).

Methods: The Pubmed, Embase, Medline, Cochrane Central Register of Controlled Trials (CENTRAL) as well as the Information Sciences Institute (ISI) Web of Science were searched for all the controlled studies that compared HFNC with NIPPV and COT when used before MV in adult patients. The primary outcome was the rate of endotracheal intubation and the secondary outcomes were intensive care unit (ICU) mortality and length of ICU stay (ICU LOS).

Results: Eight trials with a total of 1084 patients were pooled in our final studies. No significant heterogeneity was found in outcome measures. Compared both with COT and NIPPV, HFNC could reduce both of the rate of endotracheal intubation (OR 0.62, 95% CI 0.38-0.99, P=0.05; OR 0.48, 95% CI 0.31-0.73, P=0.0006) and ICU mortality (OR 0.47, 95% CI 0.24-0.93, P=0.03; OR 0.36, 95% CI 0.20-0.63, P=0.0004). As for the ICU LOS, we did not find any advantage of HFNC over COT or NIPPV.

Conclusions: When used before MV, HFNC can improve the prognosis of patients compared both with the COT and NIPPV.

Keywords: Endotracheal intubation; High flow nasal cannula; Meta-analysis; Mortality.

Publication types

  • Comparative Study
  • Meta-Analysis
  • Review
  • Systematic Review

MeSH terms

  • Cannula
  • Clinical Trials as Topic
  • Critical Care / statistics & numerical data
  • Humans
  • Intubation, Intratracheal / mortality
  • Intubation, Intratracheal / statistics & numerical data*
  • Oxygen Inhalation Therapy / methods
  • Oxygen Inhalation Therapy / mortality
  • Positive-Pressure Respiration / methods
  • Positive-Pressure Respiration / mortality
  • Respiration, Artificial / methods*
  • Respiration, Artificial / mortality