Volta 2007.

Methods	Randomised controlled study. List of random numbers generated by computer. Patients were managed postoperatively by anaesthetists who were masked to the aims of the study
Participants	36 patients undergoing major abdominal surgery for colon cancer. Exclusion criteria: aged < 18, cardiac insufficiency, kidney dysfunction, altered liver function, preoperative anaemia, preoperative coagulation abnormalities, and long‐term use of corticosteroids or NSAIDs
Interventions	1) 3.4% Poligeline (n = 12) 2) HES 130/0.4 (n = 12) A third group received RL (n = 12)
Outcomes	Haemodynamic variables
Notes	Follow‐up 72 hours
Risk of bias
Bias	Authors' judgement	Support for judgement
Allocation concealment (selection bias)	Unclear risk	Unclear. Data on allocation not provided