Awake Craniotomy (AC) is the “gold standard” technique for intractable epilepsy or resection of anatomically challenging tumours. Monitored anaesthesia care (MAC) and asleep-awake-asleep (SAS) are the two most adopted protocols. We aim to synthesise the most recent evidence and try to establish which anaesthetic technique for AC is safer and more effective. We used random-effects modelled meta-analysis and followed the Cochrane methodology for Meta-Analysis and Systematic Reviews. Medline and Embase databases were searched for studies published between January 2014 up to September 2018. We included both randomised controlled trials and observational studies that analysed the incidence of AC failure and other complications as the duration of surgery and the length of stay in hospital in adults patients (age ≥ 18) undergoing AC.

We included eighteen studies. AC failure rates in the two subgroups MAC and SAS\cite{Qu2020} were 1% and 5% respectively. The proportion of intraoperative seizures was 10% and 4%.  The incidence of intraoperative nausea and vomiting was 4% and 8%. The pooled mean of the duration of surgery was 224.44 mins and 327.94 mins, and of the length of stay in the hospital was 3.96 days for MAC and 6.75 days for SAS. Comparing MAC directly to SAS, we found a statistically significant lower risk of AC failure during MAC (OR, 0.28; 95% CI, 0.11–0.71; p=0.007) as a shorter procedure time (MD, -48.76 mins; 95% CI, -61.55 to -35.97; p<0.00001). SAS was associated with less risk of intraoperative seizures (OR, 2.38; 95% CI, 1.05–5.39; p=0.04). Awake surgery for brain lesions or refractory epilepsy is safe, well tolerated and complications are uncommon. Large randomised controlled trials are still needed.