Cell saving systems do not reduce the need of transfusion in low-risk patients undergoing cardiac surgery

Cell saving systems have been widely used to reduce blood loss and need of transfusions. These device are mainly indicated in complex cardiac surgery procedures and in those patients with a high risk of bleeding. However, it is not clear if there is a benefit of a cell saver (CS) system in low-risk patients undergoing cardiac surgery. Our aim was to analyze if the use of CS systems reduce the need of blood products in low-risk patients undergoing cardiac surgery.

Between February and June 2009 all low-risk patients (EuroSCORE<10%) undergoing coronary or valve procedure were selected (n=63). Exclusion criteria were: combined procedure, aorta procedure, redo surgery, emergency procedures, creatinine levels>2 mg/ml, anemic patients and patients with a body surface area (BSA)<1.6 m2. Patients were randomized to undergo cardiac surgery with a cell saving system (group CS) (n=34) or without (control group, CO) (n=29). All patients received tranexamic acid during the procedure. Need of blood products and clinical outcomes were analyzed in both groups.

Mean age was 64.7±12.3 years old with 33% of female patients. Baseline clinical characteristics and preoperative blood count cell were similar in both groups. Mean CS blood reinfused was 461±174 ml (maximum: 985 minimum: 259). A total of 59 red blood packages were transfused in 25 patients (mean 1.02±1.3; range: 0-5). The proportion of patients being transfused was similar in both groups (CS: 40% vs. CO: 46.4%; P=0.79). Eleven plasma packages were transfused (CS: 8 vs. CO: 3; P=0.77) and three platelet pools were used in group CS and none in group CO (P=0.08). Multivariate analysis showed that preoperative hemoglobin levels>13.3 g/dl [relative risk (RR): 0.29; confidence interval (CI): 0.09-0.99] and BSA>1.74 (RR: 0.19; CI: 0.54-0.68) were protective against blood transfusion.

In low-risk patients CS system did not reduce the need of blood transfusion. Clinical outcomes were similar regardless of the use of a cell saver system. A low preoperative hemoglobin level and a low BSA were related with the use of blood products.