Retrograde autologous priming to reduce allogeneic blood transfusion requirements: a systematic review.

BACKGROUND: Efforts have been made to minimize transfusion of packed red blood cells in patients undergoing cardiac surgery with cardiopulmonary bypass. One method concerns retrograde autologous priming. Although the technique has been used for decades, results remain contradictory in terms of transfusion requirements. OBJECTIVE: This systematic literature review aimed to summarize the evidence for the efficacy of retrograde autologous priming in terms of decreasing perioperative packed red blood cell requirements in adults. METHODS: Two researchers independently searched PubMed for articles published in the past 10 years. The modified Cochrane collaboration Risk of Bias Tool and the Research Triangle Institute Item Bank were used to assess bias. RESULTS: Eight studies were included, of which two randomized and six observational studies. Five studies, including one randomized study, report a significant decrease in packed red blood cell use in the retrograde autologous priming group compared to no retrograde autologous priming used. All studies are flawed by at least a high risk bias of bias score on one item of the bias assessment. CONCLUSION: Although most studies reported significantly fewer packed red blood cell transfusions in the retrograde autologous priming group, it is important to note that relatively few articles are available which are flawed by several types of bias. Prospective, randomized multi-center trials are warranted to conclude decisively on the benefits of retrograde autologous priming.