Onan 2011.

Methods	Parallel RCT Ethics committee: approved Informed consents: obtained Site: Kocaeli, Turkey Setting: university hospital Dates of data collection: not reported Funding: unspecified Registration: unspecified
Participants	30 participants; mean age: 59.0 years; sex distribution: 3 females and 27 males Inclusion criteria Patients with documented 3‐vessel coronary artery disease who were scheduled for elective coronary artery bypass graft surgery Exclusion criteria Decreased ventricular function (ejection fraction 40%) Emergency operation Previous cardiothoracic operation Unstable angina Resting bradycardia (< 60 beats/min) Critical left main coronary artery disease (50% stenosis) Contraindications to the epidural technique including pre‐existing coagulopathy Preoperative anticoagulation (full therapeutic doses of standard or low–molecular‐weight heparin, warfarin, thrombolytic drugs, or potent antiplatelet drugs) Systemic or local infection Previous cervical or upper thoracic operation Vertebral deformity Drug hypersensitivity
Interventions	Intervention Epidural analgesia (N = 15) Comparator Systemic analgesia (N = 15) Premedication: midazolam Induction: midazolam, fentanyl, and rocuronium Maintenance: nitrous oxide, propofol, fentanyl, and rocuronium Surgery: CABG with CPB
Outcomes	Relevant to this review Risk of mortality Risk of myocardial infarction Others Immunoreactivity Graft blood flow
Notes	Correspondence: email sent 16 March 2018; no reply Conflict of interest: not reported DOI: 10.1053/j.jvca.2011.06.004
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Randomization was performed immediately before surgery using sealed envelopes
Allocation concealment (selection bias)	Low risk	Randomization was performed immediately before surgery using sealed envelopes
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Not reported
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Not reported
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	No failed epidural reported Groups had similar demographic data