Washing of banked blood by three different blood salvage devices

Storage lesions in red blood cells (RBCs) lead to an accumulation of soluble contaminants that can compromise the patient. Organ failures, coagulopathies, and cardiovascular events including lethal cardiac arrest have been reported, especially with massive transfusion or in pediatric patients. Washing improves the quality of stored RBCs, and autotransfusion devices have been proposed for intraoperative processing, but these devices were designed for diluted wound blood, and limited data on their performance with RBCs are available.

Three autotransfusion devices (Electa, Sorin; CATS, Fresenius; OrthoPAT, Haemonetics) differing in function of their centrifugation chambers were evaluated with RBCs at the end of their shelf life and with dilutions thereof. Elimination rates of potassium, plasma free hemoglobin, total protein, citrate, acid equivalents, and iomeprol added as a marker substance were analyzed, in addition to RBC recoveries.

Product hematocrit (Hct) levels ranged between 54.8 and 72.6%. RBC recovery rates were between 62.7 and 95.0%, the lowest being with the OrthoPAT processing of undiluted RBCs. Plasma elimination rates increased with predilution and ranged from 46.6% to 99.5%, the lowest being with the CATS and undiluted RBCs. Washing did not change pH and buffering capacity of RBCs.

Autotransfusion devices offer a practical and obviously economical option to wash banked RBCs intraoperatively to prevent hyperkalemia and other disturbances in massive transfusion or pediatric patients. Predilution improves elimination rates, especially in devices that produce high product Hct levels. With a Y-tubing the RBCs should bypass reservoir and vacuum, and the procedure should be guarded by a policy and procedure manual and a quality management system.