Frecuencia de registros cardiotocograficos sugerentes de perdida de bienestar fetal y su relación con los resultados perinatales en un hospital de tercer nivel

Abstract

Introduction: Currently there is limited scientific literature on cardiotocography tracing frequencies and its relation to perinatal outcomes. Objective: The objective of the study was to determine the frequency of ¿nonreassuring¿ cardiotocographic tracings (categories II, "sub II", III) during labor and the last two hours antepartum of women assissted in the delivery room of Vall d'Hebron Hospital and to analyze their relationship with short-term adverse neonatal outcomes and operative deliveries. Method: Observational study of a prospective cohort. The intrapartum cardiotocographic tracings of 379 pregnant women with a singleton fetus of ¿ 35 weeks were analyzed using the National Institute of Child Health and Human Development classification and a sub-category ("sub II") created ad hoc. The duration of time in each category was calculated and related to neonatal adverse outcomes and to operative deliveries. Results: Considering the entire delivery, category II was present in 41.67%, the category "sub II" 17.5% and category III 0.0%. In the last two hours, category II increased to 60.83%, the category "subII" to 33.33% and category III could not be calculated either. The "sub II" category at two hours antepartum was significantly more observed in acidotic fetuses. Category II and "sub II" were significantly more observed during labor and at two-hour antepartum in neonates with adverse events as well as cesarean or instrumental deliveries. Conclusions: Category II is more frequent than the "sub II" category during labor and both increase in the last two hours antepartum. This study shows an association between length of stay in these categories and short-term adverse neonatal outcomes and operative deliveries. Keywords: fetal heart rate, cardiotocography, fetal monitoring, fetal hypoxia, nonreassuring fetal status, fetal distress, fetal hypoxia.