HEMOLYSIS FOLLOWING RAPID EXPERIMENTAL RED-BLOOD-CELL TRANSFUSION - AN EVALUATION OF 2 INFUSION PUMPS

Background: The vast majority of infusion pumps used for rapid transfu sion of large amounts of blood have never been properly examined regar ding their influence on the quality of the red blood cells (RBCs) infu sed. In this study, we evaluated the effect of two different infusion pumps on the degree of RBC destruction following rapid experimental bl ood transfusion Methods: Divided into 2 groups according to age, 30 u of SAGM RBCs were infused through an experimental transfusion model by either a manual roller pump (MRP) or a pressure infusor pump (PIP). F resh (i.e stored for 8-11 d) RBCs, 20 u, and 10 u of older (i.e. store d for 25-33 d) RBCs were randomly allocated to infusion with either of the two pumps. The rate of infusion was as fast as possible with the MRP, and with the PIP adjusted with an external applied pressure of 30 0 mm Hg. RBC samples collected before and after infusion were analyzed for total haemoglobin, free haemoglobin, haematocrit, total free pota ssium, lactate dehydrogenase (LDH) and the percentage of haemolysis. T he time spent for each transfusion was measured by a stop watch. Resul ts: Following infusion, a marginal increase (i.e. considerably below 0 .8%) in the percentage of haemolysis and LDH content was seen with bot h pumps. This increase was only statistically significant when RBCs st ored for 8-11 d were used (P = 0.002 for both parameters). Irrespectiv e of the age of the RBCs, no differences between the two pumps could b e detected. Compared to the PIP, infusion with the MRP could be accomp lished significantly faster, i.e. median 5.9 ml/s (5.2-6.4 ml/s) versu s 2.9 ml/s (2.5-3.2 ml/s), (P<0.0001). Conclusions: Both the pumps use d in this study are safe alternatives for rapid transfusion of RBCs; h owever, with MRP this can be accomplished approximately twice as fast as with the PIP. (C) Acta Anaesthesiologica Scandinavica 42 (1998).