The PREVENNT randomised, double-blind, controlled trial of preoperative intravenous iron to treat anaemia before major abdominal surgery: an independent discussion.

Anaemia is a common finding in patients presenting for major elective surgery and is associated with poor outcomes including death and complications. Iron deficiency is the leading cause of perioperative anaemia. Intravenous (i.v.) iron is considered to be an effective and safe treatment for iron deficiency anaemia and is recommended by expert opinion for treatment of preoperative anaemia, although evidence from clinical trials is lacking. The PREVENTT trial was a large multicentre trial investigating the effects of i.v. iron on red cell transfusion, death, complications and quality of life in 487 patients undergoing major abdominal surgery. The principal finding of this multicentre randomised placebo controlled trial was that there was no difference in the co-primary outcomes of blood transfusion or death, or the number of transfusion episodes, within 30 days after surgery, in patients that received preoperative i.v. iron therapy compared to placebo. The major inferential differences in this independent discussion relate to the limitations of the PREVENTT trial and its implications for future practice. Although PREVENTT represents the best evidence available to guide perioperative use of i.v. iron, it is likely that the study was underpowered. In the context of already widespread adoption of preoperative i.v. iron therapy, many clinicians may have felt they lacked equipoise. In light of the PREVENTT study routine use of i.v. iron in patients undergoing elective abdominal surgery cannot be recommended. Further research should define the optimum red cell transfusion strategy for patients undergoing surgery and idenify other surgical groups who may benefit from this intervention.