Daniel L Keene, David Roberts, William M Splinter, Michael Higgins and Enrique Ventureyra

Abstract:   Purpose: Alfentanil is a potent, short-acting opioid agent which has been used during balanced anaesthesia in children undergoing the surgical excision of epileptic foci. After the observation that this agent had the potential to induce epileptic seizures, we questioned the frequency of this occurrence in this group of patients. Method: Twelve patients (6 males, 6 females) undergoing surgical excision of an epileptic foci were prospectively followed. For each patient an electrocorticogram was recorded for 30 minutes before and after receiving alfentanil 20 µg/kg intravenously. The frequency of epileptiform abnormalities before and after drug administration was evaluated. When the electrocorticogram no longer showed the effects of alfentanil administration, methohexital 0.5 µg/kg was given intravenously. Results: Alfentanil induced 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 epileptiform discharges in 50% of these patients. None experienced electrographic seizures. Conclusions: As alfentanil can induce electrographic seizures in patients known to have epilepsy, caution is advised in its use in this group of patients.

Can. J. Neurol. Sci. 1997; 24: 37-39