Kirno 1994.

Methods	Parallel RCT Ethics committee: approved Informed consents: obtained Site: Goteberg, Sweden Setting: university hospitals Dates of data collection: unspecified Funding: this work was supported by grants from the Swedish Medical Research Council (No. 08682,09047, and 09720), the Medical Faculty at the University of Goteborg, the Medical Society of Goteborg, and the Swedish Heart‐Lung Foundation Registration: unspecified
Participants	20 participants: mean age: not reported; sex distribution: not reported Inclusion criteria Patients undergoing coronary artery bypass grafting All patients had a history of stable ischaemic heart disease with 2‐ or 3‐vessel coronary artery disease Ejection fraction > 50% Exclusion criteria Patients with coexisting valvular anomaly, arrhythmias, or diabetes mellitus
Interventions	Intervention Epidural analgesia (N = 10) Comparator Systemic analgesia (N = 10) Induction: thiopental, pancuronium, and fentanyl Maintenace: nitrous oxide in oxygen and fentanyl Surgery: CABG with CPB
Outcomes	Relevant to this review Risk of mortality Haemodynamic variables Others Regional myocardial oxygen consumption Myocardial ischaemia Noradrenaline spillover (sympathetic nervous system activation)
Notes	Correspondence: letter sent 16 March 2018; no reply Conflict of interest: none reported DOI: n/a
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Participants were randomized to 2 groups; no details provided
Allocation concealment (selection bias)	Unclear risk	Not reported
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 prespecified outcomes reported
Other bias	Unclear risk	No failed epidural reported No details on preoperative groups' demographic data