COVID-19 Evidence Alerts
from McMaster PLUSTM

Current best evidence for clinical care (more info)

COVID-19 Evidence Alerts needs your support. If our service is of value to you, please consider donating to keep it going. Learn more Donate now

Treatment Grieco DL, Menga LS, Cesarano M, et al. Effect of Helmet Noninvasive Ventilation vs High-Flow Nasal Oxygen on Days Free of Respiratory Support in Patients With COVID-19 and Moderate to Severe Hypoxemic Respiratory Failure: The HENIVOT Randomized Clinical Trial. JAMA. 2021 Mar 25. pii: 2778088. doi: 10.1001/jama.2021.4682.

Importance: High-flow nasal oxygen is recommended as initial treatment for acute hypoxemic respiratory failure and is widely applied in patients with COVID-19.

Objective: To assess whether helmet noninvasive ventilation can increase the days free of respiratory support in patients with COVID-19 compared with high-flow nasal oxygen alone.

Design, Setting, and Participants: Multicenter randomized clinical trial in 4 intensive care units (ICUs) in Italy between October and December 2020, end of follow-up February 11, 2021, including 109 patients with COVID-19 and moderate to severe hypoxemic respiratory failure (ratio of partial pressure of arterial oxygen to fraction of inspired oxygen =200).

Interventions: Participants were randomly assigned to receive continuous treatment with helmet noninvasive ventilation (positive end-expiratory pressure, 10-12 cm H2O; pressure support, 10-12 cm H2O) for at least 48 hours eventually followed by high-flow nasal oxygen (n = 54) or high-flow oxygen alone (60 L/min) (n = 55).

Main Outcomes and Measures: The primary outcome was the number of days free of respiratory support within 28 days after enrollment. Secondary outcomes included the proportion of patients who required endotracheal intubation within 28 days from study enrollment, the number of days free of invasive mechanical ventilation at day 28, the number of days free of invasive mechanical ventilation at day 60, in-ICU mortality, in-hospital mortality, 28-day mortality, 60-day mortality, ICU length of stay, and hospital length of stay.

Results: Among 110 patients who were randomized, 109 (99%) completed the trial (median age, 65 years [interquartile range {IQR}, 55-70]; 21 women [19%]). The median days free of respiratory support within 28 days after randomization were 20 (IQR, 0-25) in the helmet group and 18 (IQR, 0-22) in the high-flow nasal oxygen group, a difference that was not statistically significant (mean difference, 2 days [95% CI, -2 to 6]; P = .26). Of 9 prespecified secondary outcomes reported, 7 showed no significant difference. The rate of endotracheal intubation was significantly lower in the helmet group than in the high-flow nasal oxygen group (30% vs 51%; difference, -21% [95% CI, -38% to -3%]; P = .03). The median number of days free of invasive mechanical ventilation within 28 days was significantly higher in the helmet group than in the high-flow nasal oxygen group (28 [IQR, 13-28] vs 25 [IQR 4-28]; mean difference, 3 days [95% CI, 0-7]; P = .04). The rate of in-hospital mortality was 24% in the helmet group and 25% in the high-flow nasal oxygen group (absolute difference, -1% [95% CI, -17% to 15%]; P > .99).

Conclusions and Relevance: Among patients with COVID-19 and moderate to severe hypoxemia, treatment with helmet noninvasive ventilation, compared with high-flow nasal oxygen, resulted in no significant difference in the number of days free of respiratory support within 28 days. Further research is warranted to determine effects on other outcomes, including the need for endotracheal intubation.

Trial Registration: Identifier: NCT04502576.

Discipline / Specialty Area Score
Intensivist/Critical Care
Hospital Doctor/Hospitalists
Internal Medicine
Infectious Disease
Coming soon...
Comments from MORE raters

Intensivist/Critical Care rater

The helmet interface has potential to change how we offer non-invasive oxygen support. Unfortunately, this is in essence a pilot trial; however, the results are promising and should lead to larger and more definitive studies.

Intensivist/Critical Care rater

This is a very helpful clinical trial that provides some of the best evidence to date on the best form of respiratory support for patients with COVID-19. As an intensivist, this article can help to inform decision-making regarding the use of helmet-NIV vs HFNC. While some centres may not have the helmet-NIV interface, it is still helpful (and reassuring) to note that HFNC is at least comparable to that form of respiratory support, even if the rate of intubation is slightly higher. More evidence is required for a definitive answer as to whether HFNC or NIV should be used in COVID, but this is the best and most useful evidence to date.

Respirology/Pulmonology rater

Helmet ventilation is another option to treat patients who cannot tolerate or use other modes of ventilation. This is a newer technology, so needs troubleshooting before its use.