Doppler velocimetric indices from the abdominal and placental ends of the umbilical artery of growth-restricted fetuses.

PURPOSE: In normal pregnancies, as gestation advances, a progressive decrease is observed in the differences between Doppler indices recorded at the 2 extremities of the umbilical cord. The purpose of this study was to determine whether the same pattern is observed in pregnancies complicated by intrauterine growth restriction (IUGR). METHODS: Forty-seven fetuses with sonographic diagnosis of IUGR underwent investigation by Doppler sonography. Blood flow velocities were measured at the abdominal and placental ends of the umbilical cord. The systolic-diastolic ratio, pulsatility index, and resistance index were calculated for each site. The differences in values between the 2 ends of the cord were calculated (abdominal end minus placental end) and then compared with the differences calculated for normal fetuses. RESULTS: In contrast to normal fetuses, IUGR fetuses with abnormal Doppler measurements had significant differences in the pulsatility and resistance indices between the 2 ends of the cord after 28 weeks of gestation. In addition, when compared with normal fetuses, the IUGR fetuses had a significantly greater difference in the values for the 2 ends of the cord for all indices. CONCLUSIONS: These results emphasize the importance of identifying the sampling site for serial Doppler investigations in IUGR-complicated pregnancies.

Fatal neonatal lactic acidosis with respiratory insufficiency due to complex I and IV deficiency.

We present a newborn boy who died after 53 days of life in respiratory failure with lactic acidosis. Analysis of skeletal muscle mitochondria demonstrated a combined defect in complexes I and IV of the respiratory chain. The boy had severe muscle hypotonia but no signs of encephalopathy, illustrating the variation in multi-organ presentation of mitochondrial defects.