Intrapartum fetal heart rate patterns and neonatal intraventricular hemorrhage

The predictive value of intrapartum fetal heart rate abnormalities in the extremely premature infant

OBJECTIVE

Our purpose was to evaluate the validity of intrapartum fetal heart rate tracings in predicting short- and long-term outcomes of infants delivered between 24 and 26 weeks.

STUDY DESIGN

Fetal heart rate tracings obtained during the last hour before delivery of fetuses delivered at 24 to 26 weeks' gestation were reviewed. Two perinatologists blinded to neonatal outcome evaluated the tracings for the following attributes: baseline rate and variability, presence and severity of decelerations, and overall impression (reassuring, nonreassuring, or ominous). Measured outcomes were cord blood pH; Apgar scores; intraventricular hemorrhage; duration of assisted ventilation; and hospitalization, survival, and developmental status at 1 year.

RESULTS

The fetal heart rate attribute that was found to be predictive of neonatal outcome was the presence of any bradycardia or tachycardia found in any 10-minute window (designated "baseline rate abnormality"). This correlated with neonatal death (p < 0.007). None of the other fetal heart rate attributes were associated with any neonatal outcome. Intraobserver agreement was "fair to good" (kappa 0.5).

CONCLUSION

Fetal baseline rate abnormalities (either tachycardia or bradycardia) were predictive of neonatal death in extremely premature fetuses.

The paradox of electronic fetal monitoring: more data may not enable us to predict or prevent infant neurologic morbidity

Electronic fetal heart rate monitoring has been used to identify periods of fetal risk, with the hope that clinical intervention would avoid the potential for perinatal death or neurologic damage. A literature review of 10 infant studies failed to document fetal heart rate patterns associated with neurologic injury or protocols for intervention to avoid neurologic injury. A separate analysis of fetal heart rate patterns from 55 brain-damaged infants failed to find consistent patterns that foreshadowed the observed brain injury. These findings should not be surprising, because the majority of infant brain damage occurs outside the intrapartum period and because electronic monitoring may identify times of fetal risk but was never expected to identify brain damage.