Ativaçåo do sistema complemento causada pela circulaçåo extracorpórea em crianças submetidas à cirurgia cardíaca / Complement cascade activation due to cardiopulmonary bypass in children undergoing heart surgery

RESUMO

Complement activation was studied in 10 children undergoing heart surgery with (group 1) and in 9 children undergoing heart without cardiopulmonary bypass (group 2). Children with infectious disease and under corticotherapy as well as those with immunological disease were excluded. Cardiopulmonary bypass was performed with bubble oxygenators, primed with blood and crystalloid. Blood samples were drawn at hte beginning oh the operation and approximately 15 minutes before skin closure. Plasma concentrations of the third component factor (C3) and of its split product C3d were measured in all patients. C3 levels were expressed in mg/dl and C3d levels were expressed as a percentage of a normal control value. Plasma concentrations of C3 decreased significantly in group 1 (84.8 more or less 14.7 mg/dl and 34.2 more or less 8.2 mg/dl; p=0.007) and remained unchanged in group 2 (91 more or less 11.9 mg/dl and 85.9 more or less 13.4 mg/dl; p=0.13-NS). Plasma concentrations of C3d rose significantly in group 1 (12928.5 and 33867.5; p=0,005) but remained unchanged in group 2(86 more or less 15.1 and 93 more or less 21.3; p=0.10-NS). We concluded that the third componenet of the complement system C3 was consumed during the cardiopulmonary bypass and this consumption was due to activation