White 2003.

Methods	RCT, parallel design
Participants	Total number of randomized participants: 30 Inclusion criteria: ASA status I or II; scheduled to undergo gynaecological procedures under GA Exclusion criteria: women with clinically significant cardiovascular, pulmonary, renal, hepatic, and neurologic diseases; body weight > 100% above the ideal; history of alcohol or drug abuse Type of surgery: gynaecological procedures Baseline characteristics Intervention group (esmolol) Age, mean (SD): 41 (± 11) years Control group (placebo) Age, mean (SD): 37 (± 6) years Country: USA Setting: single centre; hospital
Interventions	Intervention group (esmolol) Randomized, n = 15; losses = 0; analysed, n = 15 Details: after induction of anaesthesia, 50 mg esmolol and 1 mL normal saline, IV Control group (placebo) Randomized, n = 15; losses = 0; analysed, n = 15 Details: 5 mL normal saline, then 1 mL normal saline, given same as the intervention group
Outcomes	Outcomes measured/reported by study authors: haemodynamic variables; premature ventricular contractions (short run); transient nodal rhythm; adverse cardiovascular events (not defined); BIS; recovery times; length of hospital stay (min); postoperative analgesics and antiemetic medication; intraoperative recall Outcomes relevant to the review: length of hospital stay (see notes below)
Notes	Funding/declarations of interest: supported by department funding and endowment funds (Margaret Milam McDermott Distinguished Chair in Anesthesiology) Study dates: not reported Note: study includes an additional group (esmolol + nicardipine), which we did not include in the review we did not combine in analysis data for length of hospital stay, which were reported in minutes, rather than days ‐ esmolol group, mean (SD): 218 (± 88) min; control group, mean (SD): 269 (± 100) min
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Not specified
Allocation concealment (selection bias)	Unclear risk	Not specified
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Described as placebo‐controlled, double‐blinded study; we therefore assumed that anaesthetists were blinded to study drugs
Blinding of outcome assessors (detection bias) All outcomes	Unclear risk	Not specified
Incomplete outcome data (attrition bias) All outcomes	Low risk	No apparent losses
Selective reporting (reporting bias)	Unclear risk	Study authors did not report prospective clinical trial registration or publication of a protocol. It was not feasible to effectively assess risk of reporting bias
Other bias	Low risk	Not detected