Does Curarisation before Hand Improve Ventilation by Face Mask? A Prospective Randomised Study

Prior verification of the efficiency of face mask ventilation before curarisation is most often dogmatic. It is often considered a safety factor. The main aim of our study was to investigate the effect of prior curarisation on face mask ventilation conditions. Materials and methods: A prospective, randomised, double-blind study was carried out in the operating theatre of the Mohammed V military training hospital in Rabat. The inclusion criteria were: patients aged over 18 years, with an American Society of Anesthesiologists (ASA) I and II score, scheduled for surgery under general anaesthesia and requiring tracheal intubation. Exclusion criteria were: the presence of gastro-oesophageal reflux, the need for rapid sequence induction, the presence of criteria for face mask ventilation or difficult intubation and the need for vigorous intubation. The patients included were randomised into two groups : the rocuronium group, in whom curarisation with rocuronium prior to verification of the efficacy of VMF was performed, and the control group, in whom an equal volume of 0.9% saline was administered.  Improvement in face mask ventilation was our primary endpoint. It was assessed using the HAN face mask ventilation difficulty score and tele-expiratory volume (TEV) during mask ventilation manoeuvres. Results : A significant improvement in the Han score was noted at 2 min after administration of rocuronium (1.40 ± 0.50 vs 2 min : 1.17 ± 0.38, p=0.017). There was also a significant improvement in TEV at 1 min (117.9 ± 41.41 vs 289.33 ± 78.63, p=0.004) and at 2 min after early curarisation (167.57 ± 59.7 vs 388.67 ± 38.85, p=0.008). Conclusion : Prior curarisation improves face mask ventilation in patients with an easy planned airway. Several studies with different methodologies found similar results.