Background: High-flow nasal oxygenation (HFNO) for pre-oxygenation in rapid sequence induction (RSI) has only been assessed in volunteer parturients without intubation.
Objectives: To evaluate the efficacy of HFNO in comparison with the conventional facemask for oxygenation during RSI for caesarean section under general anaesthesia.
Setting: Operating room in a tertiary hospital.
Design: Prospective randomised, controlled study.
Participants: Thirty-four healthy parturients undergoing general anaesthesia for caesarean section.
Interventions: Parturients were randomly assigned to HFNO or standard facemask (SFM) group.
Main outcome measures: The primary outcome measure was the PaO2 immediately after intubation. Secondary outcomes included lowest saturation throughout the intubation procedure, end-tidal oxygen concentration (EtO2) on commencing ventilation, blood gas analysis (pH, PaCO2), fetal outcomes and intubation-related adverse events.
Results: PaO2 in the HFNO group was significantly higher than that in SFM group (441.41 ± 46.73 mmHg versus 328.71 ± 72.80 mmHg, P < 0.0001). The EtO2 concentration in the HFNO group was higher than that in the SFM group (86.71 ± 4.12% versus 76.94 ± 7.74%, P < 0.0001). Compared to baseline, PaCO2 immediately after intubation also increased significantly in both groups (HFNO group: 30.87 ± 2.50 mmHg versus 38.28 ± 3.18 mmHg; SFM group: 29.82 ± 2.57 mmHg versus 38.05 ± 5.76 mmHg, P < 0.0001), but there was no difference in PaCO2 between the two groups. There was no difference in lowest saturation, intubation times, duration of apnoea, pH value or fetal outcomes.
Conclusions: Compared with SFM, HFNO provided a higher PaO2 and EtO2 immediately after intubation in parturients. HFNO is safe as a method of oxygenation during RSI in parturients undergoing general anaesthesia for caesarean section.
Trial registration: Clinical trial ChiCTR1900023121.
Copyright © 2020 European Society of Anaesthesiology and Intensive Care. Unauthorized reproduction of this article is prohibited.