Performing real time neuropsychological testing during awake craniotomy: are dexmedetomidine or propofol the same? A preliminary report

Purpose In awake surgery, the patient is sedated, but is also required to be sufficiently alert and collaborative during extensive neurocognitive testing. In the present preliminary report of a retrospective single-center study, a continuous series of 168 patients who underwent awake surgery for brain tumor located near eloquent areas, was investigated to observe the effect of dexmedetomidine (n = 58) compared with propofol (n = 110) on vigilance and collaboration required to perform extensive intra-operatory Real Time Neuropsychological Testing (RTNT). Methods We assigned a score to each patient, by using a scale that combines vigilance and collaboration in a 5 levels score (the higher score denoting higher level). Results The median interquartile range was significantly lower (range 3-5) for the dexmedetomidine group compared to the propofol one (range 4-5, p = .044). Patients with intra-operative seizures (p = .014) and/or electrocorticographic slow/epileptiform activity (p = .042), and patients in the propofol group who showed increased heart rate (p = .032) were those who obtained the lower scores (lower vigilance and collaboration level). Conclusion The study shows that the effect of dexmedetomidine or propofol -based conscious sedation on ability to perform Real Time Neuropsychological Testing during awake surgery for supratentorial tumor resection is different. Although both permit high mean levels of vigilance and collaboration, the patient who received dexmedetomidine was more likely to show lower vigilance and collaboration during RTNT.