McFarlane 1994.

Methods	Design: randomized controlled trial Withdrawals: none Setting: single centre (UK) Sample size: 30
Participants	Age (mean): 57/54 years Gender (M/F): not described ASA grade: I or II Surgery type: major elective hepatobiliary or pancreatic surgery Surgery duration (mean): 3.3/3.7 hours Anaesthesia type: general
Interventions	Intervention n = 15 Buffered arm ‐ Plasmalyte 148 infusion 15 mL/kg/h Control n = 30 Non‐buffered arm ‐ normal saline infusion 15 mL/kg/h Rate adjusted in response to clinical state, but not according to a clinical protocol Co‐interventions: all fluids warmed
Outcomes	Blood loss (mL/kg) mean and SD, chloride, bicarbonate, base excess, PaCO2, lactate up to 24 hours postoperatively
Notes	Funding source: not disclosed Declarations of interest: none disclosed
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Randomization method not clear
Allocation concealment (selection bias)	High risk	No evidence of allocation concealment
Blinding of participants and personnel (performance bias) All outcomes	High risk	No evidence of blinding
Blinding of outcome assessment (detection bias) All outcomes	High risk	No evidence of blinding
Incomplete outcome data (attrition bias) All outcomes	Low risk	All outcome data complete
Selective reporting (reporting bias)	Low risk	No evidence of selection bias. All proposed outcome measures adequately reported
Other bias	Low risk	No other information forthcoming