Priestley 2002.

Methods	Parallel RCT Ethics committee: approved by the local hospital Research and Ethics Committee Informed consents: all participants gave written informed consent Site: Westmead Hospital, Westmead, Australia Setting: university hospital Dates of data collection: unspecified Funding: this study was supported by the Australian and New Zealand College of Anaesthetists Registration: unspecified
Participants	100 participants; mean age: 59 years; sex distribution: 14 females and 86 males Inclusion criteria Patients scheduled for elective CABG Exclusion criteria Contraindications to the epidural technique (e.g. preexisting coagulopathy, anticoagulation (i.e. full therapeutic doses of standard or low‐molecular‐weight heparin, warfarin, thrombolytic drugs, or potent antiplatelet drugs), systemic or local infection) Arthritis of the thoracic or cervical spine with a history of associated neurological deficit Coexisting surgery (e.g. valvular, carotid, aortic surgery) Contraindications to any of the intended drugs in the treatment protocol Significant alcohol or other substance abuse Cognitive impairment Other reason for inability to comply with treatment as assessed by investigators
Interventions	Intervention Epidural analgesia (N = 50) Comparator Systemic analgesia (N = 50) Premedication: lorazepam, morphine, and midazolam Induction: fentanyl, propofol, and pancuronium Maintenance: fentanyl, propofol, and pancuronium Surgery: CABG with CPB
Outcomes	Relevant to this review Risk of mortality Risk of myocardial infarction Risk of neurological complications Tracheal extubation Pain scores Others Pain scores Lung function Length of hospital stay Mobilization goals
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)	Low risk	Block randomization via sealed envelopes was used; participants at high risk were randomized separately
Allocation concealment (selection bias)	Low risk	Sealed envelopes
Blinding of participants and personnel (performance bias) All outcomes	High risk	Quote: "blinding of participants or investigators was not considered feasible"
Blinding of outcome assessment (detection bias) All outcomes	High risk	Quote: "blinding of participants or investigators was not considered feasible"
Incomplete outcome data (attrition bias) All outcomes	Low risk	Fifty participants were enrolled into each group, and data were analysed on an intention‐to‐treat basis. A per‐protocol analysis was also performed, and 12 participants were excluded from such analysis: 4 failed epidural blocks, 3 surgical complications required reoperation (2 systemic analgesia, 1 epidural analgesia), 1 underwent reintubation (epidural) for respiratory failure, and 4 had protocol violations (3 systemic analgesia and 1 epidural analgesia)
Selective reporting (reporting bias)	Low risk	All results reported
Other bias	Low risk	Groups had similar demographic data