Late-onset fetal cardiac decelerations associated with fetal breathing movements.

BACKGROUND: While late decelerations are regarded as signs of fetal hypoxemia, fetal breathing movements (FBM) associated with late decelerations invariably have normal outcomes. Could late decelerations sometimes represent FBM? MATERIALS AND METHODS: Six patients between 37 and 42 weeks' gestation with 'late decelerations' associated with FBM (by ultrasound or tocodynamometer) during ante- or intrapartum monitoring were evaluated. Three were at high risk (diabetes, postdates, intrauterine growth restriction) and three were at low-risk. RESULTS: 'Late decelerations' arose in previously reassuring tracings. Oxygen or positional change had no effect. The decelerations were variable in length and shallow, and contained increased variability. Normal baseline rate and variability were maintained after the deceleration. Neonatal outcomes were normal. CONCLUSION: 'Late decelerations' as described are associated with normal outcome and may represent FBM. This understanding may reduce unnecessary interventions.

Medicolegal ramifications of electronic fetal monitoring during labor.

Fetal heart rate patterns play a significant role in the modern day obstetric care. They also play a significant role in medicolegal allegations of negligence when the fetus suffers injury. Proper interpretation of the fetal monitor tracing is only one factor in the evaluation of the reasonableness of obstetric care. Appropriate care and optimal defense both derive from reasonable interpretation of pertinent clinical data, including the monitor strip, along with timely pursuit of a thoughtful, properly annotated, plan of care.

Intrapartum electronic fetal heart rate monitoring versus intermittent auscultation: a meta-analysis.

OBJECTIVE: To use a meta-analysis of all published randomized trials to determine whether the use of continuous electronic fetal heart rate monitoring (EFM) as the main method of intrapartum fetal surveillance is associated with improved pregnancy outcome compared to intermittent auscultation. DATA SOURCES: We used the MEDLINE data base and reference lists of articles to identify all published randomized trials of EFM versus intermittent auscultation. METHODS OF STUDY SELECTION: A total of nine randomized trials published in peer-review journals were identified. The selection criterion was the use of EFM or intermittent auscultation as the main intrapartum fetal surveillance technique. DATA EXTRACTION AND SYNTHESIS: A total of 18,561 patients were included in the nine published randomized trials, 9398 in the EFM group and 9163 in the auscultation group. Measures of pregnancy outcome included cesarean delivery, cesarean for suspected fetal distress, overall use of forceps or vacuum, use of forceps or vacuum for suspected fetal distress, overall perinatal mortality, and perinatal mortality due to fetal hypoxia (intrapartum or early neonatal death) attributable to the method of intrapartum monitoring. The meta-analysis showed that the patients monitored electronically had a significantly higher overall cesarean rate (odds ratio [OR] 1.53, 95% confidence interval [CI] 1.17-2.01), higher cesarean rate for fetal distress (OR 2.55, 95% CI 1.81-3.53), overall increased use of forceps or vacuum (OR 1.23, 95% CI 1.02-1.49), increased use of forceps or vacuum for suspected fetal distress (OR 2.50, 95% CI 1.97-3.18), and decreased perinatal mortality due to fetal hypoxia (OR 0.41, 95% CI 0.17-0.98). CONCLUSION: Electronic fetal monitoring is associated with increased rates of surgical intervention and decreased perinatal mortality due to fetal hypoxia.

Intrapartum, atraumatic, non-asphyxial intracranial hemorrhage in a full-term infant.

BACKGROUND: Intracranial hemorrhage in a full-term infant is uncommon, is usually subarachnoid in type, and is usually associated with operative vaginal delivery or asphyxia. CASE: A 15-year-old primigravid woman at 37 weeks' gestation developed a prolonged second stage of labor associated with persistent occiput posterior position. With the onset of pushing, baseline fetal heart rate (FHR) decreased and variability increased. Thirty minutes before vaginal delivery, sudden fetal tachycardia (up to 210 beats per minute) was observed, with absent variability and minimal decelerations. At birth, the infant was apneic and hypotonic, but lacked biochemical evidence of acidemia or asphyxia; seizures developed in the early neonatal period. Subarachnoid hemorrhage was demonstrated by computed tomography of the head. CONCLUSION: The occiput posterior position, marked molding, and prolonged labor with compulsive pushing may be associated with an increased risk of adverse outcome, even unrelated to the details of delivery. The change in FHR pattern, to a lowered baseline rate and increased variability, suggests increased intracranial pressure. The sudden change to fetal tachycardia with absent variability before delivery suggests intracranial hemorrhage or injury.

The ABCs of electronic fetal monitoring.

There have been too many surrogates used to define fetal asphyxia and too many surrogates used to time fetal injury. Low Apgar scores and the need for prolonged resuscitation, by themselves, are inadequate criteria for the diagnosis of perinatal asphyxia or subsequent neurologic handicap. Even with the addition of a low cord pH and seizures, it is not possible to infer neurologic handicap. Furthermore, acidosis and depression at birth (which should be referred to as "perinatal asphyxia") cannot measure the duration and extent of any prenatal asphyxial encounter. Nor can we use the absence of one or more of these signs to exclude perinatal asphyxia as the cause of injury. We cannot refer to fetal asphyxia and injury therefrom without defining our criteria and describing the model of asphyxia being invoked. Because ischemia to the brain and other organs (that is, localized asphyxia), not systemic global asphyxia, appears to be the major precursor of human fetal injury it seems unreasonable to insist on systemic fetal asphyxia at any time to validate the timing or mechanism of fetal injury. Most hypoxic newborn infants are not injured and most injured newborn infants are not hypoxic. Furthermore, that a baby is injured as a result of hypoxia during labor does not mean that the hypoxia was preventable. FHR patterns, properly interpreted, may be one of the most reliable determinants of subsequent neurologic outcome and depending on the circumstances may provide insight into the timing and mechanism of neurologic injury.(ABSTRACT TRUNCATED AT 250 WORDS)

Fetal heart rate patterns and the timing of fetal injury.

We studied the nonstress test (NST) results and other perinatal features of 44 children with cerebral palsy, who had fetal heart rate (FHR) patterns during labor suggesting preexisting injury. This was a retrospective, descriptive study. All fetuses persistently showed absent variability and small, variable decelerations, with overshoot from the onset of monitoring during labor. During the initial NST, 84.1% of fetuses revealed normal reactive NST patterns (three with decelerations). Six fetuses (15.9%) had nonreactive NST results (three with decelerations). The conversion of the reactive NST to a pattern of persistently absent variability often occurred during advanced pregnancy (average estimated gestational age 40 weeks), in association with decreased amniotic fluid (AF) volume (70.5%) and maternal complaints of decreased fetal movement (52.4%). FHR decelerations consistent with acute fetal distress were uncommon during early labor but occurred in about half of cases in advanced labor. All but one neonate had low Apgar scores at birth, but acidosis occurred in about one third of infants. Seizures developed in about half the infants, usually in the first day. Follow-up studies revealed a high incidence of mental retardation, microcephaly, and seizure activity in addition to cerebral palsy, regardless of the presence of perinatal acidosis. The results of this retrospective study of a limited population base suggest that fetal neurologic injury preceding labor may develop late in pregnancy, and that decreased AF volume appears to be a significant risk factor. FHR patterns may provide clues to the presence and timing of fetal neurologic injury.