A prospective, randomized comparison of cobra perilaryngeal airway and laryngeal mask airway unique in pediatric patients

BACKGROUND: The Cobra Perilaryngeal Airway (PLA) provides better sealing pressure than the Laryngeal Mask Airway Unique (LMAU) during positive-pressure ventilation in adults. We compared the performance of the CobraPLA and LMAU in infants and children. METHODS: Two-hundred pediatric patients were randomly assigned to a CobraPLA or an Laryngeal Mask Airway (LMA). We measured airway sealing at cuff inflation pressures of 40 and 60 cm H2O; ease and time of insertion; device stability; efficacy of ventilation; number of insertion attempts; incidence of postoperative sore throat, dysphonia, laryngospasm, bronchospasm, and gastric gas insufflation. Steady-state end-tidalCO2 was measured at the head of the CobraPLA and at the "Y-piece" piece of the anesthetic circuit. For the major outcomes, the airway groups were subdivided post hoc into small and large CobraPLA and small and large LMA subgroups. Results are presented as means ± sds; P < 0.05 was considered statistically significant. RESULTS: Airway sealing pressure with the cuff inflated to 60 cm H2O in the large CobraPLA subgroup (22 ± 7 cm H2O) was significantly more than that of the small CobraPLA subgroup (18 ± 5 cm H2O) and large LMA subgroup (16 ± 5 cm H2O; P < 0.001). The CobraPLA was more stable than the LMA (same anatomic fit score before and after surgery) and produced less gastric insufflation. Head CobraPLA end-tidalCO2 values were 6.4 ± 6 mm Hg more than those of the Y piece of the circle circuit. CONCLUSIONS: The CobraPLA airway performed as well as the LMAU during anesthesia in pediatric patients for a large range of outcomes and was superior for some.