Do Blood Transfusions During Colorectal Cancer Surgery Increase Mortality?

Albert B. Lowenfels, MD


November 07, 2012

Effects of Allogeneic Red Blood Cell Transfusions on Clinical Outcomes in Patients Undergoing Colorectal Cancer Surgery: A Systematic Review and Meta-analysis

Acheson AG, Brookes MJ, Spahn DR
Ann Surg. 2012;256:235-244


The investigators reviewed 55 published studies (20,795 patients) to determine the effects of blood transfusion on patient outcome after colorectal surgery. They found that blood transfusion increased overall mortality by about 70% (P < .001) as well as cancer-associated mortality (P < .001). A significant increase in other measures was found, such as length of stay and postoperative wound infection and reoperation.


This large and ambitious review and meta-analysis investigated reports going as far back as the 1990s. Although the investigators concluded that blood transfusion is the driving force leading to adverse outcomes after colorectal surgery, an alternative viewpoint is that factors associated with preoperative anemia or increased operative bleeding lead to increased mortality rates. It is difficult to accurately adjust for factors such as surgical ability or tumor size -- factors that are likely to be associated with increased overall and tumor-related mortality. There are ethical problems in constructing a randomized trial, but it seems reasonable that factors leading to increased blood loss, rather than giving the patient blood, is the reason for adverse results after transfusions. Nevertheless, surgeons will agree that avoiding blood loss during colorectal surgery should be given high priority.