Laryngeal mask airway insertion by anesthetists and nonanesthetists wearing unconventional protective gear - A prospective, randomized, crossover study in humans

Background: Mass casualty situations impose special difficulties in airway management, even for experienced caregivers. The laryngeal mask airway is part of the difficult airway algorithm. The authors evaluated the success rate and the time to secure airways by mask by anesthetists, surgeons, and novices when wearing either surgical attire or full antichemical protective gear that included butyl rubber gloves and a filtering anti-gas mask. Methods: Twenty anesthetists and 22 surgeons with 2-5 yr of residency inserted a laryngeal mask airway in 84 anesthetized patients, and 6 novices repetitively inserted masks in 57 patients under both conditions in a prospective, randomized, crossover manner. The duration of insertion was measured from the time the device was first grasped until a normal capnography recording was obtained. Results: Anesthetists needed 39 +/- 14 s to insert the masks when wearing surgical attire and 40 +/- 12 s with protective gear. In contrast, surgery residents needed 64 +/- 40 and 102 +/- 40 s (P = 0.0001), respectively. Anesthetists inserted masks in a single attempt, whereas the surgeons needed up to four attempts with no hypoxia or failure associated. The initial attire-wearing novices' insertions took as long as the surgeons; three of them then reached the mean performance time of the anesthetists after four (protective gear) and two (surgical attire) trials, with only one occurrence of hypoxia and a failure rate similar to that of the surgeons. Conclusions: Anesthesia residents insert laryngeal mask airways at a similar speed when wearing surgical attire or limiting antichemical protective gear and two to three times faster than surgical residents or novices wearing either outfit. Novices initially perform at the level of surgical residents, but their learning curve was quick under both conditions.