Background: Pre-hospital endotracheal intubation is challenging and repeated endotracheal intubation is associated with increased morbidity and mortality. We investigated whether the introduction of the McGrath MAC video laryngoscope as the primary device for pre-hospital endotracheal intubation could improve first-pass success rate in our anaesthesiologist-staffed pre-hospital critical care services. We also investigated the incidence of failed pre-hospital endotracheal intubation, the use of airway adjuncts and back-up devices and problems encountered using the McGrath MAC video laryngoscope.
Methods: Prospective quality improvement study collecting data from all adult pre-hospital endotracheal intubation performed by four anaesthesiologist-staffed pre-hospital critical care teams between December 15(th) 2013 and December 15(th) 2014.
Results: We registered data from 273 consecutive patients. When using the McGrath MAC video laryngoscope the overall pre-hospital endotracheal intubation first-pass success rate was 80.8 %. Following rapid sequence intubation (RSI) it was 88.9 %. This was not significantly different from previously reported first-pass success rates in our system (p = 0.27 and p = 0.41). During the last nine months of the study period the overall first-pass success rate was 80.1 (p = 0.47) but the post-RSI first-pass success rate improved to 94.4 % (0.048). The overall pre-hospital endotracheal intubation success rate with the McGrath MAC video laryngoscope was 98.9 % (p = 0.17). Gastric content, blood or secretion in the airway resulted in reduced vision when using the McGrath MAC video laryngoscope.
Conclusion: In this study of video laryngoscope implementation in a Scandinavian anaesthesiologist-staffed pre-hospital critical care service, overall pre-hospital endotracheal first pass success rate did not change. The post-RSI first-pass success rate was significantly higher during the last nine months of our 12-month study compared with our results from before introducing McGrath MAC video laryngoscope. The implementation of the Standard Operating Procedure and check list for pre-hospital anaesthesia during the study period may have influenced the first-pass success rate and constitutes a potential confounder. The potential limitations of the McGrath MAC video laryngoscope when there are gastric content, blood and secretions in the airways need to be further investigated before the McGrath MAC video laryngoscope can be recommended as the primary device in all pre-hospital endotracheal intubations.
Keywords: Difficult endotracheal intubation; Emergency medical services; First-pass success rate; McGrath MAC; Out-of-hospital; Pre-hospital; Prehospital; Rapid sequence intubation; video laryngoscope.