High flow nasal therapy in immunocompromised patients with acute respiratory failure: A systematic review and meta-analysis

Purpose: The role of high-flow nasal therapy (HFNT) as compared to conventional oxygen therapy (COT) in immunocompromised patients admitted to intensive care unit (ICU) with acute respiratory failure (ARF) remains unclear. We conducted a systematic review and meta-analysis in order to address this issue. Methods: We searched PubMed, Medline and Embase until November 7th, 2018. Randomized controlled trials (RCTs), non-randomized prospective and retrospective evidence were selected. Observational studies were considered for sensitivity analysis. Primary outcome was mortality rate; intubation rate was a secondary outcome. Results: We included four studies in the primary analysis: one RCT, two RCT's post-hoc analyses and one retrospective study. We found no significant difference in short-term mortality comparing HFNT vs. COT: 1) ICU: n = 872 patients, odds ratio (OR) = 0.80 [0.44,1.45], p = 0.46, I 2 = 30%, p = 0.24; 2) 28-day: n = 996 patients, OR = 0.79 [0.45,1.38], p = 0.40, I 2 = 52%, p = 0.12). Conversely, we found a reduction of intubation rate in the HFNT group (n = 1052 patients, OR = 0.74 [0.55,0.98], p = 0.03, I 2 = 7%, p = 0.36). The inclusion of one observational study for sensitivity analysis did not grossly change results. Conclusions: We found no benefit of HFNT over COT on mortality in immunocompromised patients with ARF. However, HFNT was associated with a lower intubation rate warranting further research.