An ultrafiltration technique for directly reinfusing residual cardiopulmonary bypass blood.

Given the shortages of banked blood, the risks of transfusion reactions, disease transmissions, and transfusion errors, we perfusionists must find ways to avoid blood transfusions. At the end of any given bypass run, there is residual blood left in the bypass circuit, the perfusionist must get this blood back to the patient. Most commonly either a cell saver or a hemoconcentrator (HC) has been used, in some fashion, to reinfuse residual circuit blood. The ideal method should: 1) be simple; 2) raise the hematocrit (HCT); 3) allow for changes in the patient's volume status; and 4) not compromise the integrity of the cardiopulmonary bypass (CPB) circuit allowing for rapid re-institution of CPB. We describe a technique in which residual CPB circuit blood is pumped through an HC directly to the patient via a 3/16-inch diameter line into a 16-gauge intravenous needle positioned in a peripheral or central vein. This allows the perfusionist to give back concentrated blood that is protein-rich while maintaining the above criteria.

A clinical comparison of two commercially available pediatric hemoconcentrators.

Hemoconcentration is a technique that involves selective removal of plasma water and some dissolved solutes by way of an ultrafiltration membrane. Hemoconcentrators (HC) are routinely used during pediatric cardiopulmonary bypass (CPB) to remove free plasma water and various inflammatory mediators. This paper examines two different commercial HCs, the Dideco DHF0.2 and the Minntech Hemocor HPH 400. Both products were evaluated when used for prebypass ultrafiltration (Pre-BUF), and postbypass modified ultrafiltration (MUF). Five HCs were evaluated for each product, and the two groups were compared during the two different phases of the cardiac procedure. During the pre-BUF period, both groups of HCs were tested at a transmembrane pressure (TMP) gradient of 500 millimeters of mercury (mmHg). The mean amount of ultrafiltrate (UF) removed by the Dideco DHF0.2 was 81.4 milliliters per minute (mL/min), and the mean amount of UF removed by the Minntech Hemocor HPH 400 was 90.8 mL/min during the pre-BUF period. During the peribypass period flow parameters were much harder to define. As a result, these data are not reported. During the MUF procedure, the mean amount of UF removed by the Dideco DHF0.2 was 74.2 mL/min at an average MUF flow rate of 130 mL/min. The mean amount of UF removed by the Minntech Hemocor HPH 400 was 81.4 mL/min at an average MUF flow rate of 127 mL/min. Both products performed adequately under the clinical circumstances described above. The Minntech HPH 400 produced a hemofiltrate that was consistently tinged with a slight red color. The Dideco DHF0.2 consistently produced a hemofiltrate that was noticeably clearer than that of the Minntech device.