[Decrease in allogenic transfusions due to the spread of use of postoperative retransfusion systems in knee...

Surgical teams have several tools in order to reduce the need for postoperative allogenic transfusion. Postoperative autotransfusion of unwashed shed blood has become common practice for total knee replacement surgery since 2006 in our hospital. This study was designed to evaluate if this practice has reduced allogenic blood transfusions.

A retrospective study comparing two cohorts, group 2004 with patients operated on for total knee replacement during the year 2004, before the use of the retransfusion system, and group 2008, patients operated on in the year 2008, with regular use of the retransfusion system. Gender, preoperative and postoperative haemoglobin levels, total amount of calculated erythrocytes lost, reinfusion of shed blood and allogenic blood transfusion during hospital stay were recorded.

Both groups were similar as regards gender, preoperative and postoperative hemoglobin levels, and total amount of erythrocytes lost. The proportion of transfused patients was significantly lower in group 2008 versus group 2004 (20.18% versus 42.19%), with a relative risk of being transfused of 0.47 and a NNT of 4.54. P=.0017.

In our hospital the use of postoperative retransfusion systems has reduced the proportion of transfused patients during hospitalization for total knee replacement surgery, although this result cannot be generalized due to the lack of a fixed transfusion trigger.