Dexmedetomidine as adjunct in awake craniotomy – improvement or not?

Background
Over the last decade, awake craniotomy for tumor resection has become a standard to maximize tumor resection and minimize the risk of permanent neurological deficits. Different techniques and medication regimes have been tested for this procedure. Until today there is no consensus on the optimal approach. Therefore, we investigated the effect of dexmedetomidine as an adjunct in awake cerebral tumor surgery and evaluated our improved technique.

Methods
Data of patients who underwent awake craniotomy for tumor resection at our institution between 09/2006 and 05/2018 were retrospectively analyzed. All patients were kept awake after cortical mapping. After changing our standard anesthetic procedure from propofol/remifentanil alone to propofol/remifentanil and dexmedetomidine, we performed an evaluation of time to arousal, drug dosages, patients’ cooperation and the occurrence of periprocedural adverse events.

Results
Eighty-four patients received propofol/remifentanil alone (SG). A further 17 patients additionally received dexmedetomidine following craniotomy in order to induce rapid arousal (DG). In the dexmedetomidine group a significantly reduced infusion time for propofol (169.2 ± 47.4 vs. 212.9 ± 63.3 minutes; P = 0.008) and non-significantly shorter time to arousal (12.0 [10.0/16.5] vs. 15.0 [10.0/20.0] minutes; P = 0.271) could be identified. In general, the overall procedure was very well tolerated by all patients.

Conclusions
The asleep-awake technique is a well-accepted and safe procedure. It allows continuous surveillance of the patient’s neurological function during tumor resection and the postoperative phase, minimizing complications. In addition, our data show that the use of dexmedetomidine results in a shorter time to arousal.