Helmet and face mask for non-invasive respiratory support in patients with acute hypoxemic respiratory failure: A retrospective study

Purpose: Non-invasive respiratory support could reduce the incidence of intubation in patients with Acute Hypoxemic Respiratory Failure (AHRF). The optimal interface or modality of non-invasive respiratory support is debated. We sought to evaluate the differences between patients who succeeded or failed non-invasive respiratory support, with a specific focus on the type of non-invasive respiratory support (i.e. helmet CPAP versus face mask NIV). Materials and methods: In a single-center observational retrospective study, we investigated baseline, clinical characteristics and AHRF management by non-invasive respiratory support between January 2015 to December 2016. Data on gas exchange and respiratory mechanics, non-invasive respiratory support duration, ICU length of stay and mortality were collected. Results: 110 patients with AHRF were included of which 41 patients (37%) were intubated. The use of helmet CPAP (p = 0.016) and a lower fluid balance (p = 0.038) were independently associated with a decreased rate of intubation after adjustment for confounders. Face mask NIV patients trended to a higher respiratory frequency at 1 h after treatment [28 (22–36) versus 24 (18–29) hours, p = 0.067], and showed a longer ICU stay (p = 0.009) compared to patients treated with helmet CPAP. Conclusions: Helmet CPAP and a lower fluid balance were independent predictors of a lower intubation rate in AHRF patients in ICU. Prospective studies aimed at identifying the optimal interface and modality of non-invasive respiratory support in AHRF patients are needed.