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.

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.

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.

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.