RESUMO
OBJECTIVE: To compare tracheal intubation conditions in morbidly obese patients 60 seconds after administration of succinylcholine or rocuronium doses based on real weight or ideal weight. METHOD: We evaluated patients with a body mass index (BMI) of 40 kg x m(-2) or more but no other indications of difficult-intubation risk. Induction was performed under fentanyl and propofol at doses calculated based on real weight. Patients were assigned to 1 of 4 groups for tracheal intubation. Group 1 received 1 mg of succinylcholine per kilogram of ideal weight, group 2 received 1 mg of succinylcholine per kilogram of real weight, group 3 received 0.6 mg of rocuronium per kilogram of ideal weight, and group 4 received 0.6 mg of rocuronium per kilogram of real weight. Tracheal intubation was performed 60 seconds later and intubation conditions were recorded using a clinical scoring system. RESULTS: Eighty patients with a mean BMI of 47.5 kg x m(-2) were enrolled. The difficult intubation rate was 3.75%. All patients were intubated. Laryngoscopy conditions and position and movement of vocal cords were similar in all 4 groups. Reaction to cuff inflation revealed intergroup differences; group 3 presented slight limb movements, diaphragm movement, and sustained cough for more than 10 seconds. CONCLUSION: These results suggest that administration of succinylcholine calculated based on real weight or ideal weight and rocuronium based on real weight can provide clinically acceptable conditions for tracheal intubation in morbidly obese patients with no other difficult-intubation criteria.
