Gurses 2013.

Methods	Parallel RCT Ethics committee: approved by the Ethics Committee of the Medical School, Pamukkale University Informed consents: written informed consent was received from each individual before entry into the study Site: School of Medicine, Pamukkale University, Denizli, Turkey Setting: university hospital Dates of data collection: between July 2010 and January 2011 Funding: funded solely by the institution of the authors Registration: unspecified
Participants	64 participants; mean age: 62.3; sex distribution: 18 females and 46 males Inclusion criteria ASA II or III Aged 40 to 79 years Scheduled for elective CABG Exclusion criteria Hypersensitivity towards any of the chemicals to be used Contraindication for epidural anaesthesia (dermal infection, nervous system disease, severe hypovolaemia, high intracranial pressure, severe aorta stenosis, severe mitral stenosis, etc.) History of vertebral surgery Cervical or thoracic vertebral arthritis Morbid obesity (BMI > 35), coagulopathy, < 40% ejection fraction, and preoperative inotropic agent usage
Interventions	Intervention Epidural analgesia (N = 32) Comparator Systemic analgesia (N = 32) Induction: thiopental and rocuronium Maintenance: sevoflurane and rocuronium Surgery: CABG with CPB
Outcomes	Relevant to this review Risk of neurological complications (epidural haematoma) Risk of atrial fibrillation or atrial flutter Tracheal extubation Haemodynamic variables Others Analgesic requirements Blood transfusion requirement ICU length of stay Hospital length of stay
Notes	Correspondence: email sent 16 March 2018; no reply Conflict of interest: no conflict of interest DOI: 10.12659/MSM.883861
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Randomly assigned to study groups by the closed envelope method
Allocation concealment (selection bias)	Low risk	Randomly assigned to study groups by the closed envelope method
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 provided
Other bias	Low risk	Study groups were similar in terms of demographic variables