Girard 1986.

Methods	RCT, parallel design
Participants	Total number of randomized participants: 17 Inclusion criteria: scheduled for myocardial revascularization Exclusion criteria: severe congestive heart failure; valvular heart disease; MI within 1 month of surgery; not in sinus rhythm Type of surgery: elective myocardial revascularization Baseline characteristics Intervention group (esmolol) Age, mean (SD): 62 (± 9) years Gender, M/F: 8/1 History of MI, n: 4 History of hypertension, n: 2 Ejection fraction, mean (SD), %: 65 (± 14) Preoperative use of beta‐blockers, n: 4 Control group (placebo) Age, mean (SD): 59 (± 5) years Gender, M/F: 4/4 History of MI, n: 5 History of hypertension, n: 5 Ejection fraction, mean (SD), %: 61 (± 23) Preoperative use of beta‐blockers, n: 5 Country: USA Setting: single‐centre; hospital
Interventions	Intervention group (esmolol) Randomized, n = 9; losses = 0; analysed, n = 9 (use of ITT analysis was not reported) Details: esmolol hydrochloride 10 mL diluted in 5% dextrose to concentration of 10 µg/mL, infused after intubation, stepwise manner to achieve 100, 200, and 300 µg/kg/min, with loading dose for each of 500 µg/kg/min Control group (placebo) Randomized, n = 8; losses = 0; analysed, n = 8 (use of ITT analysis was not reported) Details: dextrose 5% given same as the intervention group
Outcomes	Outcomes measured/reported by study authors: haemodynamic parameters, discontinuation of study drug (due to bradycardia with HR < 50 bpm) Outcomes relevant to the review: bradycardia (see notes below)
Notes	Funding/declarations of interest: supported by a grant from American Critical Care Study dates: not reported Note: this study had two phases with separate participant groups and outcome data. This study is Phase I. We did not include Phase II in the review because this study reported no outcomes that were relevant to the review study authors stated "In three patients the infusion was stopped before the end of the infusion period because their CI [cardiac index] and HR fell below predetermined values of 2.1 min/m² and 50 bpm, respectively. Two of these patients were in the placebo group; the third patient was at the end of the 200 µg/kg/min esmolol infusion". We did not include these participants in analysis of bradycardia because we could not be certain to which participants the bradycardia data belonged.
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	Blinded solutions were provided by hospital pharmacy
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