Chan 1996.

Methods	RCT, parallel design, single‐centre
Participants	Total number of randomized participants: 60 Inclusion criteria ASA I, II, and III, 65 to 85 years of age, scheduled for total hip replacement surgery Exclusion criteria Significant cardiovascular, respiratory, hepatic, or renal disease Type of surgery: total hip replacement Baseline characteristics TIVA group Age, mean (SD): 68.6 (± 8) years; 15 participants were > 70 years of age Gender, M/F: 9/20 ASA grade: ASA I: 1; ASA II: 22; ASA III: 6 Inhalational maintenance group Age, mean (SD): 70.2 (± 8) years; 15 participants were > 70 years of age Gender, M/F: 8/23 ASA grade: ASA I: 1; ASA II: 23; ASA III: 7 Country: Canada Setting: hospital
Interventions	TIVA group Participants: n = 29; 0 losses Induction details: propofol at 0.75 mg/kg/min via electronic pump. Succinylcholine 1.0 mg/kg to 1.5 mg/kg to facilitate tracheal intubation Maintenance details: 60% N2O in O2. Propofol increased/decreased by 50% in response to 25% change in baseline BP or HR. Fentanyl 1 µg/kg (to a maximum of 4 µg/kg) with increase of propofol. Intraoperative muscle relaxation maintained with vecuronium. Propofol discontinued 5 minutes before end of surgery, N2O and O2 continued until end of surgery. Postoperative pain management with IV morphine as required. Use of clinical parameters (HR and BP) to monitor depth of anaesthesia Other information: evening before surgery, participants were given triazolam 0.125 mg to 0.25 mg, if required. Participants usual medication was withheld on morning of surgery. Then as premedication given 10 mL/kg IV crystalloid, then vecuronium 1 mg, and fentanyl 0.75 µg/kg Inhalational maintenance groups Participants: n = 31; 0 losses Induction details : bolus of 2 mg/kg thiopental, titrated to 4 mg/kg within 60 seconds as necessary. Succinylcholine 1.0 mg/kg to 1.5 mg/kg to facilitate tracheal intubation Maintenance details: 60% N2O in O2. 0.5% to 1.5% isoflurane end‐tidal concentration increased/decreased by 50% in response to 25% change in baseline BP or HR. Fentanyl 1 µg/kg (to a maximum of 4 µg/kg) with increase of propofol. Intraoperative muscle relaxation maintained with vecuronium. Isoflurane discontinued 5 minutes before end of surgery, N2O and O2 continued until end of surgery. Postoperative pain management with IV morphine as required Other information: premedication etc. same as TIVA group
Outcomes	Dose requirement Duration of anaesthesia Haemodynamics (to include hypotension) Myocardial ischemias Recovery (to include time in PACU) Mental alertness Adverse effects (PONV)
Notes	Funding/declarations of interest: not reported Study dates: not reported
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Use of a computer‐generated random number list
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	Low risk	Discharge from the PACU was assessed by a blinded independent investigator. Study authors do not report whether assessment of hypotension was done by a blinded investigator
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	N2O in O2 used in both groups in addition to other agents. However, unlikely to affect results.