The Use of Aprotinin to Reduce Transfusion Requirements in Children Undergoing Cardiac Surgery: A Meta-Analysis.

Background. Aprotinin, an antifibrinolytic medication, reduces the requirement for allogeneic red blood cell (RBC) transfusion following elective cardiac surgery in adults. The effect of aprotinin for this indication in children is unclear.

Objective. To determine if intravenous aprotinin, administered perioperatively to patients <18 years of age undergoing cardiac surgery with cardiopulmonary bypass (CPB), reduces post-operative allogeneic blood transfusion requirements (RBCs or whole blood transfusions), compared to children who do not receive aprotinin.

Methods. Systematic review of all relevant randomized controlled trials. We searched MEDLINE, EMBASE, the Cochrane Library and published abstracts. In duplicate, 2 investigators independently selected studies based on explicit inclusion and exclusion criteria; disagreement was resolved by consensus. Using a validated scale, and blinded to outcomes, authors and journal, 2 investigators independently rated the methodological quality of each selected study. Study results were combined using the random effects model to obtain a pooled relative risk.

Results. Of 547 studies identified, 11 studies published from 1993 to 2003 were included. Four of the 11 studies were judged to be of good methodological quality. Overall, aprotinin was associated with a lower proportion of children requiring transfusion, but this was not significant (relative risk 0.73, 95% CI: 0.51–1.04). We found significant heterogeneity among studies (I²= 73.0%, p= 0.001), attributed largely to methodological quality. When we pooled the 4 studies of good methodological quality, aprotinin significantly reduced the proportion of children requiring transfusion (relative risk 0.60, 95% CI 0.38–0.95). Aprotinin had no effect on the total amount of blood transfused or on the volume of chest tube drainage.

Conclusions. Aprotinin reduced the proportion of children exposed to allogeneic blood transfusion following cardiac surgery by 40% in randomized trials of good methodological quality. Additional high quality studies are needed to confirm the potential benefit of aprotinin in this population.