Intraoperative electroencephalography burst suppression during endoscopic third ventriculostomy: Case report and implications for neuromonitoring

Background: Endoscopic third ventriculostomy (ETV) is a common treatment for obstructive hydrocephalus. Intraoperative hemodynamic disturbances are well recognized. Their concurrent association with cortical suppression on electroencephalography (EEG), particularly burst suppression, has rarely been reported, and intraoperative EEG is seldom used during ETV. Case Description: A 28-year-old woman underwent ETV for obstructive hydrocephalus secondary to a tectal glioma. Shortly after endoscope insertion and ventricular irrigation, she developed two successive episodes of severe tachycardia and an acute hypertensive crisis, each coinciding with an abrupt bilateral fall in fronto-temporal electrocortical activity with burst suppression on two-channel processed EEG. Irrigation was stopped and the endoscope was withdrawn. Systemic hemodynamics normalized within 15 min, whereas the EEG required 55 min to recover. The patient recovered to near-baseline within 4 h. Conclusion: This report represents only the second published case coupling an acute intraoperative hemodynamic surge with bilateral EEG burst suppression during ETV. Processed intraoperative EEG may be an additional early sign of an acute disturbance of cerebral function. Its added value remains unproven, since a hemodynamic emergency already mandates cessation of irrigation and endoscope withdrawal. Prospective evaluation with finer temporal sampling and raw-EEG recording is warranted.