Sustained hematological consequences in the first week of neonatal life secondary to placental dysfunction

Abstract

Objective: To evaluate the relationship between umbilical artery end diastolic velocity in growth restricted fetuses and neonatal hematologic parameters.

Study design: Growth restricted fetuses were studied with ultrasound and Doppler evaluations. Neonates were analyzed in two groups based on umbilical artery Doppler status: positive end-diastolic velocities (PEDV) and absent or reversed end-diastolic velocities (AEDV). At birth and throughout the first week of life, groups were compared for anemia and thrombocytopenia; transfusion of red blood cells, platelets, and fresh frozen plasma; and intraventricular hemorrhage (IVH).

Results: Seventy-three neonates met inclusion criteria, 38 with PEDV, 35 with AEDV. Those with AEDV were delivered 3 weeks earlier, were 450 g smaller, had lower cord arterial pH values, and greater cord artery base deficits (p<0.05, respectively). AEDV neonates were twice as likely to be anemic and thrombocytopenic at birth and remain so during the first week, requiring more red blood cell and platelet transfusions. There was no difference in occurrence of severe IVH between groups.

Conclusion: Hematological alterations associated with intrauterine growth restriction appear to continue into the first week of neonatal life. These are proportional to the degree of placental dysfunction and are predicted by fetal Doppler status.

Summary: Abnormal development of the placental vascular tree is the primary step in a cascade of fetal compromises leading to intrauterine growth restriction (IUGR). Doppler ultrasound evaluation of fetal and placental blood flows provides a non-invasive assessment of the fetal condition which reflects the impact of placental vascular abnormalities. The degree of placental dysfunction determines the severity of fetal disease, which can affect many fetal organ systems. In addition to disturbances in placental respiratory function, abnormal umbilical artery Doppler status is also indicative of hematologic abnormalities during fetal life and at birth. Neonates who had more severe placental dysfunction, as depicted by absent umbilical artery end diastolic velocity, were more likely to be anemic and thrombocytopenic at birth and remain so during the first week of life, and required more transfusions than those with positive end diastolic velocities. The severity of hematologic alterations during the first week of life in growth restricted neonates was proportional to and predicted by the antenatal umbilical artery end diastolic velocity Doppler status.