RESUMO
BACKGROUND: We sought to assess whether increasing a single dose of 1.5% lidocaine during thoracic epidural anesthesia (TEA) could suppress hemodynamic responses after laryngoscopy and tracheal intubation. METHODS: A total of 81 patients (ASA physical status I and II, aged 45-75) who scheduled for major abdominal surgery were enrolled. Patients were randomly assigned to three groups, for epidural injection of different amounts of 1.5% lidocaine: 0.1 ml/kg (L0.1, n = 27), 0.2 ml/kg (L0.2, n = 27), and 0.3 ml/kg (L0.3, n = 27). After 15 min, general anesthesia was induced with intravenous thiopental sodium (5 mg/kg) and rocuronium (0.9 mg/kg), followed by tracheal intubation. Changes in blood pressure and heart rate were recorded for 3 min after intubation. Maximum percentage increases in systolic blood pressure (SBP) during the 3 min after tracheal intubation from baseline and the induction value were compared. RESULTS: The maximum increases in SBP from baseline values were significantly higher in L0.1 than in L0.2 and L0.3 (22.6%; 95% CI, 12.2-33.0%; -0.5%; 95% CI, -11.1-10.0%; and -6.9%; 95% CI, -13.9-0.0%, respectively), whereas the maximum increases from induction values did not differ significantly. CONCLUSIONS: Preoperative TEA using a single dose of 1.5% lidocaine at 0.2 ml/kg attenuated hemodynamic responses during tracheal intubation but did not completely suppress blood pressure reactions to laryngoscopy and tracheal intubation.