In vitro function of granulocyte concentrates following passage through an electromechanical infusion pump

Six units of granulocytes stored for 18 hours at 20 to 24 degrees C without agitation were passed through an electromechanical infusion device pump system (test) (Abbott) and through a 170-micron filter (control). To determine the effect of needle gauge, a 19 or 23 gauge needle was attached to the end of the pump administration set. After passage through the pump, granulocytes were evaluated for signs of cytolysis and functional loss, red cells for hemolysis, platelets for release of beta-thromboglobulin, and plasma for C3a and C5a complement activation. There was no evidence (mean +/- 1 SD) of hemolysis (less than 1.0 vs. less than 1.0 mg/dl), loss of granulocytes (123 +/- 38 X 10(3)/microliters vs. 118 +/- 29 X 10(3)/microliters), changes in any of several tests of neutrophil function, increased release of beta-thromboglobulin (15.8 +/- 5.8 vs. 17.0 +/- 6.6%), or C3a complement activation (483 +/- 221 vs. 500 +/- 200 ng/ml) after passage through the pump system (p greater than 0.05). No significant differences were seen between the use of a 19 or 23 gauge needle. Based on these in vitro data, we conclude that this pump system is acceptable for use in clinical practice when control over rate and volume of granulocyte administration is important.