Comparison of laryngeal mask airway and endotracheal tube in preterm neonates receiving general anesthesia for inguinal hernia surgery: a retrospective study

BACKGROUND: Preterm neonates are at higher risk of developing inguinal hernia, and have an increased risk of perioperative adverse events. Laryngeal mask airway (LMA) is claimed to be associated to decreasing perioperative respiratory complications compared to endotracheal tube (ETT) in infants under one year of age receiving minor surgery; thus, we conducted a retrospective survey in former preterm neonates below 5000 g to compare the respiratory complications between LMA and ETT in general anesthesia for inguinal hernia surgeries. METHODS: The inclusion criteria were: gestational age at birth under 37 weeks, body weight at surgery below 5000 g, and receiving scheduled inguinal hernia repair under general anesthesia with LMA or ETT. Infants who were dependent on mechanical ventilation preoperatively were excluded. The postoperative respiratory complications including delayed extubation, re-intubation, and apnea within postoperative 24 h were compared between groups. RESULTS: From July 2014 to December 2017, 72 neonates were enrolled into final analysis. There were 57 neonates managed with LMA, and only 15 neonates intubated with ETT during the study period. The gestational age at birth and post-menstrual age at surgery showed no significant difference between groups, although in the ETT group, the body weight at birth and at surgery were lower, and more infants had history of severe respiratory distress syndrome and had received oxygen therapy within two weeks prior to surgery. Surprisingly, none one of the infants developed delayed extubation, re-intubation, or postoperative apnea in the LMA group. In the ETT group, 40 percent of the neonates could not be successfully extubated in the operation theater. CONCLUSION: In preterm neonates, even in those younger than 52 weeks post-menstrual age who undergoing inguinal hernia repair in their early infancy, LMA appears feasible and safe as the airway device during general anesthesia in specific patient group. However, anesthesiologist might prefer ETT rather than LMA in some complex situation. In neonates with lower body weight at birth and at surgery, and with a history of severe RDS and oxygen-dependence, further prospective study is required.