Complement Activation Induced by Different Tubings Used for Cardiopulmonary Bypass

Complement activation induced by latex, polyvinylchloride, and silicone tubings for extracorporeal circulation was studied in 2 in vitro situations: Fresh whole human blood mixed with priming solution was circulated through 00 cm tubing lengths for 1 hour, and small tubing pieces were incubated in fresh human serum for 7 hours. Activation of C3 and of the terminal pathway (C5–C9) was assessed in enzyme immuno assays. In both situations complement activation was significantly higher (p<0.05) than in controls. During incubation, C3 activation started later with silicone, but increased to similar levels as with polyvinylchloride after 7 hours. Latex was a significantly more potent C3 activator at 7 hours than the other materials (p<0.05), whereas polyvinylchloride induced most terminal pathway activation (p