NEW YORK (Reuters Health) – Trauma patients transfused with ABO-compatible plasma have a higher rate of complications such as sepsis and renal failure than patients given ABO-identical plasma, a new study shows.

Writing in the September issue of the Archives of Surgery, Dr. Kenji Inaba at the University of Southern California, Los Angeles, and colleagues say that, ideally, “a patient with blood group A would receive A donor plasma, a group B patient would receive B donor plasma, group O patients would receive O plasma, and, although relatively rare, group AB patients would receive AB plasma.”

In reality, however, transfusion of compatible but not ABO-identical plasma is often used. That is, group O patients could receive group A, B, or AB plasma, while group A and B patients could receive AB donor plasma.

To investigate the effect of this practice on outcomes, the researchers conducted a retrospective study of all patients requiring plasma over an 8-year period at a level 1 trauma center.

After factoring in propensity scores, the team matched 284 patients given ABO-compatible nonidentical plasma to the same number of patients who received only ABO-identical plasma. The main outcomes were mortality and complications, covering acute respiratory distress syndrome (ARDS), sepsis, renal failure, and liver failure.

Mortality rates were not significantly different at 35.2% in the ABO-compatible nonidentical group vs 33.5% in the ABO-identical group, (p=0.66), but the differences in overall complications rates was significant: 53.5% vs 40.5% in the two groups, respectively (p=0.002).

“There was a stepwise increase in complications with increasing transfusion, with a complication rate of 70.0% for patients receiving in excess of 6 U,” Dr. Inaba and colleagues found.

Lengths of stay in the ICU trended high in the ABO-compatible nonidentical group (15.6 days) compared with the ABO-identical group (12.7 days), with a similar difference in overall hospital LOS.

“Clearly, for most patients receiving plasma, this product is lifesaving and has allowed for decreased allogeneic transfusion requirements,” the authors conclude. “However, if outcomes can be improved by the transfusion of identical rather than compatible nonidentical plasma, technically this should drive a change in practice.”

Transfusion of identical plasma should be possible in most cases, they state..

Dr. Martin Schreiber at Oregon Health & Science University is not entirely persuaded that a change in practice is warranted.

In a commentary, he points out that propensity matching excluded 90% of the patient cohort, potentially leading to bias, for example, and that ARDS could have actually been transfusion-related lung injury in some cases.

Nonetheless, Dr. Schreiber agrees that the study “raises critical questions concerning the safety of hemostatic resuscitation.”

Arch Surg 2010;145:899-906.