Should we monitor with bispectral index in all patients at high risk for seizures in the operating room?

Elgueta, M F; Vega, P; Lema, G; Clede, L

We report the case of a patient with a cerebral aneurysm, located in the left middle cerebral artery. During the clipping of this aneurysm, the bispectral index (BIS) increased for no apparent reason. This was then interpreted as intraoperative non-convulsive status epilepticus. This clinical condition may have negative impact in the prognosis of the patient, so it is very important to be able to detect this conditions as early as possible. Measuring the BIS while the patient is anaesthetised could be useful in this situation, considering that an increase in values greater than 60, associated with acidosis and without any other peri-anaesthetic explanation, may provide evidence of a convulsive equivalent state, allowing appropriate action to be taken.