ALFENTANIL MEDIATED ACTIVATION OF EPILEPTIFORM ACTIVITY IN THE ELECTROCORTICOGRAM DURING RESECTION OF EPILEPTOGENIC FOCI

Purpose: Alfentanil is a potent, short-acting opioid agent which has b een used during balanced anaesthesia in children undergoing the surgic al excision of epileptic foci, After the observation that this agent h ad the potential to induce epileptic seizures, we questioned the frequ ency of this occurrence in this group of patients. Method: Twelve pati ents (6 males, 6 females) undergoing surgical excision of an epileptic foci were prospectively followed, For each patient an electrocorticog ram was recorded for 30 minutes before and after receiving alfentanil 20 mu g/kg intravenously. The frequency of epileptiform abnormalities before and after drug administration was evaluated, When the electroco rticogram no longer showed the effects of alfentanil administration, m ethohexital 0.5 mu g/kg was given intravenously, Results: Alfentanil i nduced significant activation of epileptiform discharges among 83% of these patients. Twenty-five per cent had an electrographic seizure. In comparison, methohexital induced significant activation of epileptifo rm discharges in 50% of these patients, None experienced electrographi c seizures. Conclusions: As alfentanil can induce electrographic seizu res in patients known to have epilepsy, caution is advised in its use in this group of patients.