Ceker 2015.

Methods	RCT, parallel design
Participants	Total number of randomized participants: 60 Inclusion criteria: people with hypertension controlled by ACE inhibitors; 20‐65 years of age; undergoing elective surgery Exclusion criteria: unstable angina; conduction disorder or severe arrhythmia; COPD; heart failure; valvular heart disease; use of drugs that prolong QT‐interval; electrolyte disturbances or coagulation disorders; known hypersensitivity to trial drugs; pregnant women; difficult airways Type of surgery: elective surgery (type not specified ‐ we assumed non‐cardiac) Baseline characteristics Intervention group (esmolol) Age, mean (SD): 57 (± 6.9) years Gender, M/F: 23/7 ASA status I/II: 16/14 Control group (placebo) Age, mean (SD): 57.9 (± 6.8) years Gender, M/F: 21/9 ASA status I/II: 21/9 Country: Turkey Setting: single centre; hospital
Interventions	Intervention group (esmolol) Randomized, n = 30; losses = 0; analysed, n = 30 (use of ITT analysis not reported) Details: esmolol loading dose of 500 µg/kg, followed by 100 µg/kg/min infusion, continued until 4th min after intubation Control group (placebo) Randomized, n = 30; losses = 0; analysed, n = 30 Details: normal saline, given same as the intervention group
Outcomes	Outcomes measured/reported by study authors: corrected‐QT interval; haemodynamic variables; bradycardia (HR < 50 bpm); hypotension (MAP < 55 mmHg); arrhythmias; ventricular extrasystoles Outcomes relevant to the review: hypotension; bradycardia
Notes	Funding/declarations of interest: study authors declare no conflicts Study dates: not reported
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Computer‐generated randomization
Allocation concealment (selection bias)	Low risk	See above
Blinding of participants and personnel (performance bias) All outcomes	Low risk	To ensure blinding, drugs were prepared by an anaesthetist not involved in the care of participants
Blinding of outcome assessors (detection bias) All outcomes	Low risk	ECG readings were evaluated by a cardiologist who was blind to group allocation
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