Salazar 1979.

Methods	RCT, parallel design
Participants	Total number of randomized participants: 42 Inclusion criteria: scheduled for CABG surgery; all participants taking beta‐blocker therapy preoperatively Exclusion criteria: additional procedures such as valve replacement or aneurysmectomy, or people with complicated postoperative courses such as re‐exploration for bleeding or perioperative infarction Type of surgery: elective CABG Baseline characteristics not reported by group: study authors state "There were no statistically significant differences between the two group with respect to age, sex, extent of disease, number of grafts, dosage of propranolol preoperatively, or other pertinent variables" Country: USA Setting: single centre; hospital
Interventions	Intervention group (propranolol) Randomized, n = 20; losses = 0; analysed, n = 20 (use of ITT analysis was not reported) Details: usual dose of propranolol was discontinued 10 h before surgery; then 1 mg propranolol IV, every 4 h postoperatively; then 10 mg orally every 6 h when possible. Discontinuation time point was not specified Control group (standard care) Randomized, n = 22; losses = 0; analysed, n = 22 (use of ITT analysis was not reported) Details: no additional propranolol was given
Outcomes	Outcomes measured/reported by study authors: sinus tachycardia; paroxysmal atrial tachycardia, flutter‐fibrillation; multiple atrial/nodal premature contractions; hypotension (SBP < 100 mmHg) Outcomes relevant to the review: AF; hypotension
Notes	Funding/declarations of interest: not reported Study dates: not reported
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	High risk	Open‐label trial
Blinding of outcome assessors (detection bias) All outcomes	High risk	Open‐label trial
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	High risk	Study authors reported no difference in baseline characteristics, however, no table was presented in the study report to allow for comparison. In addition, we noted that participants in either group were given supplemental propranolol to control arrhythmias. This may have influenced outcome data.