Cardiopulmonary bypass with a surface-heparinized extracorporeal perfusion system

To evaluate the effect of surface heparinization on platelet consumption during cardiopulmonary bypass (CPB) ten pigs were placed on CPB for 3 hours. All pigs were injected with autologous Indium-111 labeled platelets (300-420 uCi) 24 hours prior to CPB and were systemically heparinized prior to cannulation for CPB. CPB was established with a roller pump, a hollow fiber membrane oxygenator (HFMO, Bentley CM-50) and an arterial filter (AF, Bentley 1025). In six pigs the extracorporeal system was untreated whereas in four pigs it was surface heparinized with the Duraflo-II method. Cardiotomy suction was not used. Percent of injected radiation dose in HFMO and AF at 3 hours of CPB in the nontreated systems was 1.53 +/- 1.12 and 0.88 +/- 0.63%, whereas in the surface heparinized systems was 2.45 +/- 1.71 and 0.49 +/- 0.39% respectively (NS). (Values are mean +/- SD). Blood loss during (CPB) was 225 +/- 179 ml in the nontreated systems, and 263 +/- 103 ml in the surface heparinized systems (NS). Platelet counts were reduced by 12% or 21.8% at 3 hours of CPB in the two groups of pigs respectively (NS). No difference was observed in platelet consumption (in HFMO and in AF) or in platelet count reduction between the two groups of pigs. Surface heparinization did not improve platelet preservation in systemically heparinized pigs at 3 hours of CPB.