Neuromuscular blockade and oxygenation changes during prone positioning in COVID-19

Neuromuscular blockers (NMBs) are often used during prone positioning to facilitate mechanical ventilation in COVID-19 related ARDS. However, their impact on oxygenation is uncertain.

Multi-centre observational study of invasively ventilated COVID-19 ARDS adults treated with prone positioning. We collected data on baseline characteristics, prone positioning, NMB use and patient outcome. We assessed arterial blood gas data during supine and prone positioning and after return to the supine position.

We studied 548 prone episodes in 220 patients (mean age 54 years, 61% male) of whom 164 (75%) received NMBs. Mean PaO₂:FiO₂ (P/F ratio) during the first prone episode with NMBs reached 208 ± 63 mmHg compared with 161 ± 66 mmHg without NMBs (Δ_mean = 47 ± 5 mmHg) for an absolute increase from baseline of 76 ± 56 mmHg versus 55 ± 56 mmHg (p_adj < 0.001). The mean P/F ratio on return to the supine position was 190 ± 63 mmHg in the NMB group versus 141 ± 64 mmHg in the non-NMB group for an absolute increase from baseline of 59 ± 58 mmHg versus 34 ± 56 mmHg (p_adj < 0.001).

During prone positioning, NMB is associated with increased oxygenation compared to non-NMB therapy, with a sustained effect on return to the supine position. These findings may help guide the use of NMB during prone positioning in COVID-19 ARDS.