Medicated Activation of Epileptiform Activity in the Electrocorticogram
During Resection of Epileptogenic Foci
Daniel L Keene, David Roberts, William M Splinter, Michael Higgins
and Enrique Ventureyra
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.
J. Neurol. Sci. 1997; 24: 37-39