METHODS: A total of 138 patients aged between 18 and 65 years old with the American Society of Anesthesiologists (ASA) I or II status, who required general anaesthesia and had no contraindication towards the use of P-LMA™, were recruited. They were randomly positioned into three anatomical landmarks, which were umbilicus, lowest rib margin, and xiphoid. P-LMA™ was inserted following muscle paralysis, and the first successful placement was evaluated using positional and performance tests. Duration, ease of P-LMA™ insertion, and airway complications were compared.
RESULTS: Demographic and airway features were comparable among all groups. The P-LMA™ placement success rate improved when the table height was positioned at the lowest rib margin (p=0.002). All three positions were comparable in terms of duration, ease of insertion, and airway morbidities.
CONCLUSION: The lowest rib margin anatomical landmark can be used as a guide in achieving the optimal operating table height for successful P-LMA™ placement.