Xiang 2014.

Methods	RCT
Participants	66 adult, ASA 1 or 2 patients undergoing elective abdominal surgery
Interventions	Intervention: lumbar epidural lidocaine (n = 16) Intervention: thoracic epidural lidocaine group (n = 16) Control: epidural saline (n = 16) General anaesthesia and patient‐controlled epidural analgesia after surgery for all participants
Outcomes	Time taken for the bispectral index to decrease to 60
Notes	Study also includes an IV lidocaine group (n = 18). This study will likely be excluded, as all participants received epidural analgesia