Gursoy 2015.

Methods	RCT, parallel group, single‐centre
Participants	Total number of participants: 60 Inclusion criteria > 65 years of age, ASA I to III, scheduled for laparotomy Exclusion criteria Neurological or psychiatric illnesses Alcohol or substance misuse Significant fluid loss or electrolyte impairment. Participants were excluded during the study if they had respiratory or cardiac arrest, ischaemia, cerebral haemorrhage or long‐lasting episodes of hypotension Type of surgery: laparotomy Baseline characteristics TIVA group Age, mean (SD): 73.17 (± 6.35) years Gender, M/F: 15/15 ASA grade: not reported Inhalational maintenance group Age, mean (SD): 73.27 (± 6.15) years Gender, M/F: 13/17 ASA grade: not reported Country: Turkey Setting: hospital
Interventions	TIVA group Participants: n = 30; 0 reported losses (study authors report use of ITT analysis) Induction details: propofol 3 mg/kg to 6 mg/kg, remifentanil 1 µg/kg, vecuronium 0.1 mg/kg Maintenance details: propofol infusion of 12 mg/kg/hour, then 9 mg/kg/hour, then 6 mg/kg/hour over 10 minutes. Remifentainil 0.15 µg/kg/hour to 0.30 µg/kg/hour. 67% air and 33% O2 Inhalational maintenance group Participants: n = 30; 0 reported losses (study authors report use of ITT analysis) Induction details: thiopentone 3 mg/kg to 5 mg/kg, vecuronium 0.1 mg/kg IV Maintenance details: 2% sevoflurane, with 67% N2O/33% O2
Outcomes	Changes in MAP Cognitive dysfunction (measured at 1, 6, 12, 24 hours postoperatively with MMT)
Notes	Funding/declarations of interest: study authors report no conflict of interest Study dates: not reported Note: study report in Turkish. Review authors used Google translate to assist with translation of key paragraphs
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Participants were randomized to groups; no additional details.
Allocation concealment (selection bias)	Unclear risk	No details
Blinding of participants and personnel (performance bias) All outcomes	High risk	Not feasible to blind anaesthetists to intervention groups
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	No details
Incomplete outcome data (attrition bias) All outcomes	Low risk	No apparent loss of study participants
Selective reporting (reporting bias)	Unclear risk	Study authors do not report clinical trials registration. Not feasible to judge risk of selective outcome reporting
Other bias	Low risk	No other sources of bias identified