The asleep–awake technique using propofol–remifentanil anaesthesia for awake craniotomy for cerebral tumours

Abstract

We retrospectively reviewed the first 25 planned cases of awake craniotomies using the 'asleep-awake' technique, an alternative to the often-used 'asleep-awake-asleep' technique. The patients were anaesthetized using propofol/remifentanil anaesthesia, a laryngeal mask and controlled ventilation according to a protocol defined before the start of this series of patients. The patients were awakened before the brain mapping and were kept awake throughout the rest of the procedure allowing for additional mapping and modification of the resection of the tumour if symptoms should develop. A small dose of remifentanil was infused during this period if necessary. Twenty-three patients were mapped as planned. One patient was not awakened due to protrusion of the brain during the awakening phase. Another patient was intubated preoperatively as it was impossible to obtain a tight laryngeal mask. All of the 23 patients were awake as from when the mapping session began and throughout the rest of the operation. In five cases the resection of the tumour was modified as symptoms emerged. These symptoms all subsided in due course. No case of hypoxia was recorded. In no case the respiratory rate was below 10 breaths min-1 in the awake period. Complications were comparable to other studies. The patients in the present study were all satisfied with the method. Different methods of anaesthesia have been described, but no method has been shown to be superior. The presented method seems to be a rational and useful technique allowing for modification of tumour resection, if symptoms should develop. The method was well tolerated by the patients.