The cerebroplacental Doppler ratio and neonatal outcome in diamnionic monochorionic and dichorionic twins

Abstract

Objective: Neonatal outcome in twins was studied in relation to the cerebroplacental ratio (CPR). Methods: Seventy-five infants from twin pregnancies with fetal Doppler data obtained within 3 weeks of delivery were candidates for study (23 infants from diamnionic monochorionic and 52 infants from diamnionic dichorionic twin pregnancies). Multivariate regression analyses were expanded to include 114 twin infants (34 diamnionic monochorionic and 80 diamnionic dichorionic twins). Patients with twin transfusion syndrome were excluded from analysis in the monochorionic group. Targeted ultrasound examination with biometry was performed, and Doppler resistance index (RI) of the umbilical artery (UA) and the middle cerebral artery (MCA) were obtained, and the CPR, a measure of blood flow redistribution, was calculated. Outcome variables included major complications, growth restriction, days of ventilator and oxygen use, days in the neonatal intensive care unit and length of stay. Results:The CPR was correlated more highly with adverse outcomes such as birth weight, special-care nursery days and length of stay than were the UA RI or the MCA RI. The CPR was significantly lower in monochorionic compared with dichorionic twins (1.12 vs. 1.27, p = 0.01). Multivariate regression analyses conducted separately on each twin group also demonstrated that CPR was superior to UA RI and MCA RI in predicting length of stay and restricted growth. Among the Doppler variables, the CPR showed the highest sensitivity for growth restriction (67%). C onclusion: In twins, CPR was superior to UA RI and MCA RI in predicting adverse neonatal events.

Blood Flow Changes in Dichorionic Twins With Growth Discordance

“…Those twins were at risk of premature delivery, mean weight was significantly lower (1,460 g vs.1,980 g), and there was higher percentage of SGA infants (53.9% vs. 46.2%) and adverse fetal outcome compared to the group without the brain-sparing effect. Gaziano et al (2001) presented similar results. It has been found that the brain-sparing effect had the highest predictive value in relation to fetal growth disturbance (SGA), abnormal fetal outcome, and the length of hospitalization compared to blood flow monitoring in only one vessel.…”

“…In dichorionic pregnancy, the increase in the placental-fetal circulation reflects mainly placental failure, often preceding the occurrence of fetal heart rate abnormalities in the form of decelerations recorded by cardiotocograph (Rizzo et al, 1994). Reports of Gaziano et al (2000Gaziano et al ( , 2001 suggest the significance of the beginning and magnitude of changes in the UA in comparison to the magnitude and beginning of disturbances in MCA in predicting fetal abnormalities. In addition, they observed a higher incidence of this phenomenon in a population of monochorionic twins, which may indicate a potentially higher risk group.…”

Diastolic Dysfunction and Cerebrovascular Redistribution Precede Overt Recipient Twin Cardiomyopathy in Early-Stage Twin-Twin Transfusion Syndrome

“…An abnormal CPR has been reported in up to 42% of lowweight monochorionic-diamniotic twins, 49 in whom it was found to correlate with adverse neonatal outcomes. 14 Our findings must be viewed in light of the strengths as well as the inherent limitations of the study. Strengths of this study include a consistent patient management protocol, with evaluation at the same center and rigorous cardiac evaluation by the same personnel.…”

Discordance in fetal biometry and Doppler are independent predictors of the risk of perinatal loss in twin pregnancies

“…However, in a similar study by Gaziano et al 17 investigating CPR in twin pregnancies, the fetal Doppler data were obtained within 3 weeks of delivery.…”

“…There is limited evidence suggesting that the value of CPR in twin pregnancies could be similar to that reported in singleton pregnancies. 17 Gaziano et al 17 have demonstrated that CPR has been shown to be superior to umbilical artery (UA) and middle cerebral artery (MCA) in predicting adverse fetal and neonatal outcomes, such as growth restriction and the length of stay in the neonatal unit.…”