To investigate the effect of low-dose lidocaine on motor evoked potentials (MEP) in patients undergoing intracranial tumor resection with propofol anesthesia.
Forty patients undergoing intracranial tumor resection and required MEP monitoring were selected.They were randomly divided into the lidocaine group (Group L, n=20) and control group (Group C, n=20) by computer generated randomization. All patients were given propofol anesthesia under the guidance of bispectral index (BIS).In Group L, lidocaine 1 mg/kg was injected intravenously during anesthesia induction. Then, lidocaine was continuously pumped at the speed of 1 mg/kg·h until the operation start. Group C was given the equal volume of normal saline. Heart rate (HR), mean artery pressure (MAP), and BIS were recorded before anesthesia induction (T0), 2 min after tracheal intubation (T1), 35 min (T2) and 50 min (T3) after anesthesia induction. The amplitude and latency of MEP at T2 and T3, the total dosage of propofol, and adverse events before T3 were recorded.
Compared with Group C, HR and MAP were significantly decreased at T1 in Group L. No significant difference was observed in HR and MAP at T0, T2 and T3 between Group L and Group C. The total dosage of propofol and the incidence of adverse events were significantly lower in Group L than in Group C before T3. There was no significant difference in the amplitude and latency of MEP between the two groups at each time point.
Low-dose lidocaine has no effect on MEP in patients undergoing intracranial tumor resection. In addition, it increased hemodynamic stability, reduced propofol use, and decreased the incidence of adverse events.