Long-term outcome of COVID-19 patients treated with helmet noninvasive ventilation vs. high-flow nasal oxygen: a randomized trial

Abstract

Background: Long-term outcomes of patients treated with helmet noninvasive ventilation (NIV) are unknown: safety concerns regarding the risk of patient self-inflicted lung injury and delayed intubation exist when NIV is applied in hypoxemic patients. We assessed the 6-month outcome of patients who received helmet NIV or high-flow nasal oxygen for COVID-19 hypoxemic respiratory failure.

Methods: In this prespecified analysis of a randomized trial of helmet NIV versus high-flow nasal oxygen (HENIVOT), clinical status, physical performance (6-min-walking-test and 30-s chair stand test), respiratory function and quality of life (EuroQoL five dimensions five levels questionnaire, EuroQoL VAS, SF36 and Post-Traumatic Stress Disorder Checklist for the DSM) were evaluated 6 months after the enrollment.

Results: Among 80 patients who were alive, 71 (89%) completed the follow-up: 35 had received helmet NIV, 36 high-flow oxygen. There was no inter-group difference in any item concerning vital signs (N = 4), physical performance (N = 18), respiratory function (N = 27), quality of life (N = 21) and laboratory tests (N = 15). Arthralgia was significantly lower in the helmet group (16% vs. 55%, p = 0.002). Fifty-two percent of patients in helmet group vs. 63% of patients in high-flow group had diffusing capacity of the lungs for carbon monoxide < 80% of predicted (p = 0.44); 13% vs. 22% had forced vital capacity < 80% of predicted (p = 0.51). Both groups reported similar degree of pain (p = 0.81) and anxiety (p = 0.81) at the EQ-5D-5L test; the EQ-VAS score was similar in the two groups (p = 0.27). Compared to patients who successfully avoided invasive mechanical ventilation (54/71, 76%), intubated patients (17/71, 24%) had significantly worse pulmonary function (median diffusing capacity of the lungs for carbon monoxide 66% [Interquartile range: 47-77] of predicted vs. 80% [71-88], p = 0.005) and decreased quality of life (EQ-VAS: 70 [53-70] vs. 80 [70-83], p = 0.01).

Conclusions: In patients with COVID-19 hypoxemic respiratory failure, treatment with helmet NIV or high-flow oxygen yielded similar quality of life and functional outcome at 6 months. The need for invasive mechanical ventilation was associated with worse outcomes. These data indicate that helmet NIV, as applied in the HENIVOT trial, can be safely used in hypoxemic patients. Trial registration Registered on clinicaltrials.gov NCT04502576 on August 6, 2020.

Keywords: Acute respiratory failure; COVID-19; Helmet; High-flow nasal oxygen; Noninvasive ventilation; Patient self-inflicted lung injury (P-SILI).

Fig. 1

Study flow-chart

Fig. 2

Radar chart showing pulmonary function tests at 6 months in our cohort. Both patients treated with Helmet NIV and high-flow had reduced performance at 6 months, but there was no difference between the two groups (upper panel). Patients that did not require endotracheal intubation had pulmonary function tests at 6 months more similar to physiological values, compared to patients that required endotracheal intubation (lower panel)

Fig. 3

Radar chart showing health-related quality-of-life assessment in our cohort. For the SF-36 test the higher score represents a better subjective health experience. The top left panel shows no difference in subjective health experience at 6 months between the high-flow group and the helmet group; however, patients that required endotracheal intubation reported worse subjective health experience compared to those who avoided endotracheal intubation (top right panel). The lower panel shows the EuroQoL five dimension five levels (EQ-5D-5L). The radar chart shows the percentage of patients reporting problems in each of the five dimensions. There was no difference between the high-flow and the helmet group (bottom left panel); however, a higher percentage of patients that needed endotracheal intubation reported impairment in each of the five dimensions, compared to the patients that avoided endotracheal intubation (bottom right panel)