the effect of intravenous lidocaine on qtc changes during spinal anesthesia in elderly patients

background: prolonged qt interval may lead to serious arrhythmias and ventricular fibrillation, hence prevention of the qt-interval prolongation is crucial for physicians. the aim of this study was to assess the influence of intravenous lidocaine on the qtc interval resulting from spinal anesthesia with bupivacaine. methods: in a randomized double blind trial, fifty male patients with mean age of 70.38 and asa physical status ιι, who underwent spinal anesthesia for elective orthopedic lower limb surgical procedures, were assessed. our subjects were divided into two groups, patients randomly received intravenously either 1.5 mg/kg lidocaine 2% as test group (n=25), or 0.05 ml/kg isotonic sodium chloride as control group (n=25), just before inducing of spinal anesthesia. spinal anesthesia was performed in the sitting position with 3 ml of 0.5% hyperbaric bupivacaine. values of the qtc interval, heart rate, and arterial blood pressure were measured before spinal anesthesia as well as 1, 5, 15, and 30 minutes after spinal anesthesia. results: with respect to the within-group values, statistically significant prolongation of the qtc interval as well as hemodynamic variability were detected in the measured times after blockade. there was no statistical difference between two groups according to hemodynamic parameters and the duration of the qtc interval before spinal anesthesia and times after spinal block with bupivacaine. conclusion: administration of intravenous lidocaine may not prevent the prolongation of the qtc interval and hemodynamic changes resulting from spinal anesthesia with hyperbaric bupivacaine, in elderly subjects.