Diagnostic accuracy of fetal heart rate monitoring in the identification of neonatal encephalopathy.

Objective: To estimate the diagnostic accuracy of electronic fetal heart rate abnormalities in the identification of neonates with encephalopathy treated with whole-body hypothermia.

Methods: Between January 1, 2007, and July 1, 2013, there were 39 neonates born at two hospitals within our system treated with whole-body hypothermia within 6 hours of birth. Neurologically normal control neonates were matched to each case by gestational age and mode of delivery in a two-to-one fashion. The last hour of electronic fetal heart rate monitoring before delivery was evaluated by three obstetricians blinded to outcome.

Results: The differences in tracing category were not significantly different (neonates in the case group 10.3% I, 76.9% II, 12.8% III; neonates in the control group 9.0% I, 89.7% II, 1.3% III; P=.18). Bivariate analysis showed neonates in the case group had significantly increased late decelerations, total deceleration area 30 (debt 30) and 60 minutes (debt 60) before delivery and were more likely to be nonreactive. Multivariable logistic regression showed neonates in the case group had a significant decrease in early decelerations (P=.03) and a significant increase in debt 30 (.01) and debt 60 (P=.005). The area under the receiver operating characteristic curve, sensitivity, and specificity were 0.72, 23.1%, and 94.9% for early decelerations; 0.66, 33.3%, and 87.2% for debt 30, and 0.68, 35.9%, and 89.7% for debt 60, respectively.

Conclusion: Abnormalities during the last hour of fetal heart rate monitoring before delivery are poorly predictive of neonatal hypoxic-ischemic encephalopathy qualifying for whole-body hypothermia treatment within 6 hours of birth. LEVEL OF EVIEDENCE: II.