| Popis: |
We studied dynamic platelet and neutrophil adhesion on cardiopulmonary bypass (CPB) circuit surfaces and in internal organs by quantitative dual-isotope gamma scintigraphy. Microporous polypropylene oxygenators were allocated to four groups: uncoated (I) and siloxane/caprolactone coated (SMA) (II) Cobe Duo oxygenators (n = 8); or uncoated (III) and Carmeda heparin treated (IV) Medtronic Maxima oxygenators (n = 4). Pigs were subjected to 90min of normothermic CPB. During CPB, 4%–25% of the platelet and neutrophil populations deposited on oxygenator surfaces, in correlation with circulating cell numbers. Platelet deposits increased during the first 20–30 min of CPB in all groups; deposits stabilized, then declined slightly after 60min (I, III, IV). Deposits dropped sharply after 20min (II). Neutrophil deposits increased continuously (I, II) or stabilized (III), or were significantly reduced (IV). Post CPB, increased sequestered cell populations were observed in liver and lung, in correlation with decreased deposits of cells on circuit surfaces. Carmeda heparin treatment reduced neutrophil adhesion, but not platelet adhesion. SMA treatment reduced platelet adhesion, but not neutrophil adhesion. |
