Luchetti 1996.

Methods	RCT Approved by the institution and informed consent obtained Setting: Italy Funding: unspecified
Participants	40 ASA 2 or 3 patients scheduled for laparoscopic cholecystectomy
Interventions	Treatment group: TEA (T12‐L1; cranially directed for about 5 cm) with bupivacaine 0.5% (initial bolus) plus 0.25% and morphine for surgery (n = 20) Control group: fentanyl IV during surgery and ketorolac for the first 4 hours after surgery (n = 20) Propofol‐based general anaesthesia for all participants
Outcomes	Vomiting
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	"randomly allocated", no details
Allocation concealment (selection bias)	Unclear risk	Not mentioned
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Not mentioned
Blinding of outcome assessment (detection bias) All outcomes	Low risk	"All data were collected in a blinded manner by a physician who was unaware as to the anaesthesia technique used"
Incomplete outcome data (attrition bias) All outcomes	Low risk	No loss to follow‐up
Selective reporting (reporting bias)	Low risk	All results reported
Other bias	Low risk	Groups well balanced