Background The effect of awake prone positioning on intubation rates is not established. The aim of this trial was to investigate if a protocol for awake prone positioning reduces the rate of endotracheal intubation compared with standard care among patients with moderate to severe hypoxemic respiratory failure due to COVID-19. Methods We conducted a multicenter randomized clinical trial. Adult patients with confirmed COVID-19, high-flow nasal oxygen or noninvasive ventilation for respiratory support and a PaO2/FiO2 ratio ≤ 20 kPa were randomly assigned to a protocol targeting 16 h prone positioning per day or standard care. The primary endpoint was intubation within 30 days. Secondary endpoints included duration of awake prone positioning, 30-day mortality, ventilator-free days, hospital and intensive care unit length of stay, use of noninvasive ventilation, organ support and adverse events. The trial was terminated early due to futility. Results Of 141 patients assessed for eligibility, 75 were randomized of whom 39 were allocated to the control group and 36 to the prone group. Within 30 days after enrollment, 13 patients (33%) were intubated in the control group versus 12 patients (33%) in the prone group (HR 1.01 (95% CI 0.46–2.21), P = 0.99). Median prone duration was 3.4 h [IQR 1.8–8.4] in the control group compared with 9.0 h per day [IQR 4.4–10.6] in the prone group (P = 0.014). Nine patients (23%) in the control group had pressure sores compared with two patients (6%) in the prone group (difference − 18% (95% CI − 2 to − 33%); P = 0.032). There were no other differences in secondary outcomes between groups. Conclusions The implemented protocol for awake prone positioning increased duration of prone positioning, but did not reduce the rate of intubation in patients with hypoxemic respiratory failure due to COVID-19 compared to standard care. Trial registration ISRCTN54917435. Registered 15 June 2020 (https://doi.org/10.1186/ISRCTN54917435).

Background Preoxygenation efficacy with high‐flow nasal cannula (HFNC) in obese patients is not clearly established. The primary aim of this study was to compare heated, humidified, high‐flow nasal cannula with face mask for preoxygenation in this population. Methods We conducted a single‐centre, randomised, controlled trial. Forty subjects with BMI ≥ 35 kg m−2 were randomly assigned to receive 5.0 min of preoxygenation with face mask and 7 cm H2O of PEEP (PEEP group) or HFNC at 70 L min−1 (HF group). Following induction, bag‐mask ventilation continued until laryngoscopy, whereas HFNC was maintained before and during intubation. The primary outcomes were end‐tidal fraction of oxygen (EtO2) at 2.5 and 5.0 min duration of preoxygenation. Secondary outcomes included PaO2 and PaCO2 at 2.5 and 5.0 min of preoxygenation and at intubation. Results Mean (±SD) EtO2 was 0.89 (±0.04) versus 0.90 (±0.05) after 2.5 min (95% CI for mean difference −0.02, 0.04) and 0.93 (±0.02) versus 0.91 (±0.02) after 5.0 min of preoxygenation (95% CI for mean difference −0.03, −0.002) in the PEEP (n = 18) and HF group (n = 20), respectively. All subjects reached an EtO2 ≥ 0.85 at 5.0 min. There were no differences in mean PaO2 or PaCO2 during preoxygenation. Subjects in the HF group had a mean (±SD) apnoea time of 199 (±38) s, but no desaturation (SpO2 < 100%) occurred. Conclusions Face mask with PEEP was superior to HFNC for preoxygenation in obese subjects. HFNC provided adequate preoxygenation quality in all subjects and may be considered as an alternative to face mask in selected patients. Trial registration #ISRCTN37375068 (http://www.isrctn.com).

Background: The effect of awake prone positioning on intubation rates is not established. The aim of this trial was to investigate if a protocol for awake prone positioning reduces the rate of endotracheal intubation compared with standard care among patients with moderate to severe hypoxemic respiratory failure due to COVID-19. Methods: We conducted a multicenter randomized controlled trial. Adult patients with confirmed COVID-19, high-flow nasal oxygen or noninvasive ventilation for respiratory support and a PaO2/FiO2 ratio ≤ 20 kPa were randomly assigned to a protocol targeting 16 hours prone positioning per day or standard care. The primary endpoint was intubation within 30 days. Secondary endpoints included duration of awake prone positioning, 30-day mortality, ventilator free days, hospital and intensive care unit length of stay, use of noninvasive ventilation, organ support and adverse events. The trial was terminated early due to futility. Results: Of 141 patients assessed for eligibility, 75 were randomized of whom 39 were allocated to the control group and 36 to the prone group. Within 30 days after enrollment, 13 patients (33%) were intubated in the control group versus 12 patients (33%) in the prone group (HR 1.01 (95% CI 0.46-2.21), P=0.99). Median prone duration was 3.4 hours [IQR 1.8-8.4] in the control group compared with 9.0 hours per day [IQR 4.4-10.6] in the prone group (P=0.014). Nine patients (23%) in the control group had pressure sores compared with two patients (6%) in the prone group (difference -18% (95% CI -2% to -33%); P=0.032). There were no other differences in secondary outcomes between groups.Conclusions: A protocol for awake prone positioning increased duration of prone positioning, but did not reduce the rate of intubation in patients with hypoxemic respiratory failure due to COVID-19 compared to standard care.Trial registration: ISRCTN54918435. Registered 15 June 2020 (https://doi.org/10.1186/ISRCTN54917435)