Assessment of Functional Fibrinolysis in Cord Blood Using Modified Thromboelastography.

BACKGROUND: The fibrinolytic system in newborns is immature and probably impaired. The aim of this study was to prospectively evaluate functional fibrinolytic capacity of newborn's cord blood using a new thromboelastometry (rotational thromboelastogram, ROTEM®) test. METHODS: Infants born at Sheba Medical Center were studied prospectively. Cord blood was obtained immediately after clumping, and ROTEM parameters were assessed applying non-activated TEM (NATEM) assay with increasing concentration of tissue plasminogen activator (tPA, 0-200 U/ml). Baseline clotting time (CT), clot formation time (CFT), alpha angle, and maximum clot firmness (MCF) were compared among infants versus adults. Each infant's demographic information was prospectively followed up until discharge. RESULTS: One hundred one newborns were tested. CT and CFT values were lower and alpha angles were higher among neonate's cord blood compared to adults (n = 23; P = 0.001, 0.03, and 0.02, respectively). The addition of tPA significantly shortened CT and CFT, and reduced alpha angles and MCF in both groups. The lysis index at 30 min (LI30) and lysis onset time (LOT) decreased significantly, and fibrinolysis was more rapid in the newborns. Hematocrit and platelet counts in neonates correlated with LI30 (P = 0.035 and 0.037, respectively) and LOT (P = 0.02) when higher tPA concentrations were used. ROTEM values were unrelated to the occurrence of postnatal complications. CONCLUSIONS: This first report of functional fibrinolysis in cord blood demonstrated that neonatal fibrinolysis may be augmented as compared to adult values. Further studies are required to validate this test and assess its predictive value and clinical relevance.

Effect of maternal congenital heart defects on labor and delivery outcome: a population-based study.

OBJECTIVE: The primary objective of this study was to characterize the delivery outcome of parturients with congenital heart defects (CHD), from maternal and from neonatal perspectives. STUDY DESIGN: A retrospective population-based study was conducted, covering a 13-year period (1989-2002) with an aggregate of 151,487 deliveries of all women with and without CHD. Maternal demographics, obstetrical and medical history, delivery outcome, and neonatal outcome were drawn from a computerized perinatal database. RESULTS: Sixty-seven women with CHD had 156 deliveries. The severity of CHD, based on the New York Heart Association (NYHA) classification, was I or II in 99.1% of the deliveries. CHD patients had significantly higher rates of labor induction and neonatal malformations. Maternal CHD was discovered as an independent risk factor associated with neonatal malformations (OR 2.10, 95% CI 1.18-3.72). No significant differences were noted between women with CHD and the controls regarding maternal morbidities and Apgar scores. CONCLUSIONS: The labor outcome of CHD patients with NYHA classification I and II resembles that of non-CHD women in a tertiary center setting. Neonates of CHD mothers have higher rates of congenital malformations even among asymptomatic or mildly symptomatic mothers. A careful sonographic follow-up is warranted among all pregnancies of CHD patients.