Laryngeal mask insertion in children: a rational approach

BACKGROUND: Various techniques of laryngeal mask airway (LMATM) insertion have been described in adults but only limited clinical trials have been conducted in children despite a varying range in success rate by the recommended method. METHOD: The study was conducted in 62 ASA 1 and 2 children who were randomly allocated for the evaluation of LMA insertion by the midline approach with the cuff completely deflated (group MD, control group, n = 31) or laterally with the cuff partially inflated (group LP, study group, n = 31). Propofol was used as the sole induction agent in all children. Ease of insertion, position of the LMA with fibreoptic laryngoscope and incidence of stomach insufflation were assessed. RESULTS: Fewer attempts and a significant reduction in the time for insertion was noted in group LP (14.4 +/- 4.2 s) compared with group MD (23.1 +/- 2.1 s), P < 0.05. Despite a good seal around the cuff and satisfactory ventilation a significantly higher incidence of malposition of the LMA was recorded by intraluminal fibreoptic endoscopy in group MD (13% to nil), P < 0.05. Similarly gastric insufflation was significantly greater in group MD (42% compared with 10%). In children with grade 3 fibreoptic view significantly higher endtidal carbon dioxide values were recorded throughout the study period after LMA insertion until its removal. LMA was stained with blood in 13% children in group MD compared with 3% in group LP at the time of removal. CONCLUSION: A partially inflated cuff inserted by the lateral route is a better method of insertion in children and grade 3 fibreoptic views can be associated with a significant build up of carbon dioxide in children breathing spontaneously.