KetaDex: A Saviour for Intraoperative Multimodal Neurophysiological Monitoring in Complex Neurosurgeries

The anaesthetic mandate for a combination of electrocorticography (ECoG) and subcortical motor evoked potential mapping (SCMEPM) substantially differs from that required for each of these monitors in isolation. There is no current consensus defining the anaesthetic management for intraoperative multimodal monitoring combining these two modalities.

We report our experience of anaesthetising a drug resistant epileptic patient for craniotomy and resection of his frontal gliotic lesion. We propose a novel anaesthetic technique to cater to the multiple goals of this surgery like optimal neuromonitoring under adequate depth of anaesthesia. We used balanced anaesthesia technique. Continuous intravenous (IV) infusions of Inj. Dexmedetomidine of 1.5 mcg/kg/hour and Inj. Ketamine at 0.5mg/kg/hour were used to supplement inhalational anaesthetic titrated to a MAC up to 0.5. Neuromuscular blockade was avoided after the initial tracheal intubation dose.

To the best of our knowledge, this is the first case reporting the safety and efficacy of balanced anaesthetic technique for concurrent ECoG and SCMEPM. Successful intraoperative ECoG and SCMEPM monitoring with absent intraoperative awareness confirmed the safety of our anaesthetic technique. Through this, a composite of patient safety, surgeon satisfaction and adequate intraoperative monitoring could be achieved.