Retrograde autologous priming in cardiopulmonary bypass in adult patients: effects on blood transfusion and hemodilution.

Introduction: Retrograde autologous priming (RAP) is a cardiopulmonary bypass (CPB) method, at low cost. Previous studies have shown that this method reduces hemodilution and blood transfusions needs through increased intra-operative hematocrit.

Objective: To evaluate RAP method, in relation to standard CPB (crystalloid priming), in adult patients.

Methods: Sixty-two patients were randomly allocated to two groups: 1) Group RAP (n = 27) of patients operated using the RAP and; 2) Control group of patients operated using CPB standard crystalloid method (n = 35). The RAP was performed by draining crystalloid prime from the arterial and venous lines, before CPB, into a collect recycling bag. The main parameters analyzed were: 1) CPB hemodynamic data; 2) Hematocrit and hemoglobin values; 3) The need for blood transfusions.

Results: It was observed statistically significant fewer transfusions during surgery and reduced CPB hemodilution using RAP. The CPB hemodynamic values were similar, observing a tendency to use lower CPB flows in the RAP group patients.

Conclusion: This investigation was designed to be a small-scale pilot study to evaluate the effects of RAP, which were demonstrated concerning the CPB hemodilution and blood transfusions.