Muth 1996.

Methods	Single‐centre study in Germany
Participants	50 patients of average age 65 years undergoing elective repair of abdominal aortic aneurysm Inclusion/exclusion criteria were not described
Interventions	No warmed intravenous fluids (n = 25): total volume fluid replacement 3449 ± 1380 mL, surgical duration 173 ± 8 minutes Intravenous fluids warmed via countercurrent‐like heat exchangers (hotline) (n = 25): total volume fluid replacement 3499 ± 1623 mL, surgical duration 171 ± 59 minutes
Outcomes	Oesophageal temperature at end of surgery
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	'Random allocation according to patients' day of surgery (odd or even numbers)'
Allocation concealment (selection bias)	Unclear risk	Not described
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Not described
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Not described
Incomplete outcome data (attrition bias) All outcomes	Low risk	No loss to follow‐up
Selective reporting (reporting bias)	Low risk	No evidence of this
Other bias	Low risk	None