Medical Controversies

Collection devices that neither concentrate nor wash shed blood before reinfusion increase the risk of adverse effects. Shed blood has undergone varying degrees of coagulation/fibrinolysis and hemolysis, and infusion of large volumes of washed or unwashed blood has been described in association with disseminated intravascular coagulation.^[81] In general, blood collected at low flow rates or during slow bleeding from patients who are not systemically anticoagulated will have undergone coagulation and fibrinolysis and will not contribute to hemostasis upon reinfusion. The high suction pressure and surface skimming during aspiration and the turbulence or mechanical compression that occurs in roller pumps and plastic tubing make some degree of hemolysis inevitable. High concentrations of free hemoglobin may be nephrotoxic to patients with impaired renal function. Many programs limit the quantity of recovered blood that may be reinfused without processing. To minimize hemolysis, the vacuum level should ordinarily not exceed 150 torr, although higher levels of suction may occasionally be needed during periods of rapid bleeding.

An alternative approach is to collect blood in a canister system designed for direct reinfusion and then concentrate and wash the recovered RBCs in a blood bank cell washer. Intraoperatively collected and recovered blood must be handled in the transfusion service laboratory like any other autologous unit. The unit should be reinfused through a filter.

Some practical considerations for cell recovery programs are listed in Table 48-7 . If collected under aseptic conditions with a saline-wash device and if properly labeled, blood may be stored at room temperature for up to 4 hours or at 1–6° C for up to 24 hours, provided that storage at 1 to 6° C is begun within 4 hours of ending the collection.^[21] Note that the allowable interval of room temperature storage is shorter for recovered blood (4 hours) than for ANH blood (8 hours). Storage times are the same for recovered blood whether unwashed or washed.