BACKGROUND:Awake craniotomy (AC) are commonly performed for epilepsy and deep brain stimulation surgery and to help preserve eloquent areas during tumour resection. While they are increasingly used to reduce the length of hospital stay, ICU admissions and avoid the risks of general anaesthesia (GA), they pose a unique challenge to anaesthetists. The aim of our audit was to review the anaesthetic practice and outcomes for awake surgery in Addenbrooke’s neurosurgical unit.
METHODS:We retrospectively obtained a database of patients who had AC surgery from 1/1/15 to 15/5/17 from the hospital’s IT department. Using Excel for data entry and analysis, the required information was obtained from the e-records. 
RESULTS:510 patients underwent craniotomy over 2 ½ years and 48 cases were done as AC. Of these, 40 patients were ASA I/II and eight were ASA III. 21 cases were for resection of low grade glioma, 22 for high grade glioma and 3 for metastases. The tumour locations included the temporal (12), frontal (15), parietal (14) and insular (7). The airway assessment of most patients was without concern and one was predicted difficult. With regards to the awake techniques, 43 patients were asleep-wake, 5 patients were asleep-wake-asleep (AWA) and no patients had local anaesthesia alone with/without sedation. Three AWA patients were unplanned due to agitation/brain swelling or low GCS. All three patients had a LMA reinserted for GA conversion. The two planned AWA patients had their airway secured with an endotracheal tube (ETT) using an AirTraq device. The airway used for the asleep phase of AC was evenly divided into ETT (24) and LMA (24). Three patients who initially had LMA inserted were subsequently intubated due to ventilation problems while one patient with ETT had severe coughing on awakening. Two patients had seizures during the awake phase (the first resolved spontaneously, the second had recurrent seizures despite Keppra, phenytoin and cold saline irrigation). There were 4 cases (8%) where AC ultimately failed (one case of recurrent seizures and three cases of unplanned AWA). 
CONCLUSION:Our current anaesthetic practice for AC is associated with a high degree of success for the patients. Despite the slightly higher failed AC rate with our techniques compared to the reported 2% incidence in the literature, we attribute it to our low sample size. As our case numbers and experience with the procedure grow we expect the rate to fall and patient outcomes to improve.


10 / Service evaluation audit of awake craniotomy cases in a UK tertiary referral teaching hospital