Fibrinogen in Children Undergoing Cardiac Surgery: Is It Effective?

In Brief There is speculation based on laboratory tests and biochemical data regarding the functional integrity of the fibrinogen in young children. Recent investigations in adults have demonstrated that their fibrinogen level correlates with the thromboelastogram maximum amplitude (MA) after modification with a glycoprotein IIb/IIIa receptor blocker that uncouples platelet-fibrinogen interactions. We postulate that if the fibrinogen of young children is functionally intact then their fibrinogen levels should also correlate with modified thromboelastogram MA values as they do in adults. We compared modified and unmodified thromboelastogram variables of 250 children <2 yr old undergoing cardiac surgery with their fibrinogen levels and platelet counts. Five age groups were distinguished to determine if and when correlations become significant (<1 mo, 1–3 mo, 3–6 mo, 6–12 mo, and 12–24 mo). Fibrinogen levels correlated with modified thromboelastogram MAs only in the 12–24 mo group. In this 12–24 mo age group other correlations between fibrinogen levels and thromboelastogram variables influenced by fibrinogen also became significant, as did correlations noted in adults between platelet counts and thromboelastogram variables. We conclude that the fibrinogen of children <12 mo old with congenital heart disease is qualitatively dysfunctional. IMPLICATIONS: Fibrinogen appears to be dysfunctional in children <12 mo old with congenital heart disease based on evidence from modified thromboelastography. This may help explain the benefits of transfusing cryoprecipitate to infants after cardiopulmonary bypass and may limit the use of modified thromboelastography in transfusion algorithms for infants after cardiac surgery.