Mahmood 2007.

Methods	Randomised controlled trial. Randomisation by blocks of 6 using random number table. The study was not double blind but person analysing data was blind to study group. ITT analysis
Participants	62 patients undergoing elective infrarenal AAA surgery. Exclusion criteria: preoperative serum creatinine of more than 177 µmol/L and left ventricular ejection fraction < 40%. Also juxtarenal aneurysms and patients who had had a renal transplant
Interventions	1) HES 200/0.62 (n = 21) 2) HES 130/0.4 (n = 21) 3) Gelatin (n = 20)
Outcomes	Haemodynamic variables Deaths Red cells infused
Notes	Follow‐up 5 days, but all‐cause mortality reported for 30 days
Risk of bias
Bias	Authors' judgement	Support for judgement
Allocation concealment (selection bias)	Low risk	Adequate 'sealed envelops allocating the fluid type' were opened on the morning of surgery. Recruitment, randomisation, and concealment were carried out by the trial coordinator