A New practical Technique to Reduce Allogeneic Blood Exposure and Hospital Costs While Preserving Clotting Factors After Cardiopulmonary Bypass: the Hemobag

Background: Recent data independently linking allogeneic blood use to increased morbidity and mortality after cardiopulmonary bypass (CPB) warrants the study of new methods to employ unique and familiar technology to reduce allogeneic blood exposure. The Hemobag allows the open-heart team to concentrate residual CPB circuit contents and return a high volume of autologous clotting factors and blood cells to the patient.

Methods: Fifty patients from all candidates were arbitrarily selected to receive the Hemobag (HB) therapy. A retrospective control group of 50 non-Hemobag (NHB) patients were matched to the HB group patient-by-patient for comparison according to surgeon, type of procedure, age, body surface area (BSA), body weight and CPB time. Many efforts to conserve blood (Cell Saver and ANH) were employed in both groups. Post-CPB cell washing of circuit contents was additionally employed in the control group.

Results: There were no significant differences between the HB and NHB groups in regard to patient morphology, pre-op cell concentrations, distribution of surgeon or procedures (41% valve, 16% valve/coronary artery bypass graft (CABG), balance CABG), pump and ischemic times and Bayes National Risk scores. The average volume returned to the patient from the HB was 817+/-198 mL (1 SD). Average processing time was 11 min. The Hemobag contained an average platelet count of 230+/-80 K/mm3, fibrinogen concentration of 413 +/- 171 mg/dl, total protein of 8.0+/-2.8 gm/dl, albumin of 4.4+/-1.2 gm/dl and hematocrit of 43+/-7%. Factor VII, IX and X levels in three HB contents averaged 259% greater than baseline.

Conclusion: Substantial reductions were achieved in both allogeneic blood product avoidance and cost to the hospital with use of the HB. Infusion of the Hemobag concentrate appears to recover safely substantial proteins, clotting factor and cell concentration for all types of cardiac procedures, maintaining the security of a primed circuit.