Prolonged Fetal Heart Rate Deceleration Research Articles

Fetal Heart Rate Decelerations in Women with Sleep-Disordered Breathing.

Emerging literature has shown that women with sleep-disordered breathing (SDB) have increased risk for gestational hypertension/preeclampsia and gestational diabetes. Case reports suggest an association between maternal apnea and fetal heart rate deceleration but data are lacking on how maternal sleep impacts fetal health. Since decelerations may be associated with adverse outcomes, we sought to determine whether fetal heart rate decelerations were associated with SDB. A cohort study of third trimester pregnant women with a singleton fetus was conducted. Participants underwent a home sleep test with continuous portable electronic fetal monitoring. SDB was defined as a respiratory disturbance index (RDI)≥10 events/hour. The temporality between a respiratory event and fetal heart rate decelerations was determined to be present if a deceleration occurred < 30 s after a respiratory event. Forty women were included with mean (±SD) age, BMI, and gestational age of 32.0±5.5 years, 37.1±8.0 kg/m2, and 34.6±2.4 weeks respectively. Overall, n=23 (57.5%) women had SDB. Thirty-seven late decelerations were observed in 18 women; of these, 84% were temporally associated with a respiratory event. Nine of the 18 women (50%) had SDB. Ten prolonged decelerations were observed in 6 women of which nine (90%) were temporally associated with a respiratory event. Five of the six women (83%) had an RDI≥10. These initial data suggest that, in this population, the majority of both late and prolonged fetal heart rate decelerations occur with a maternal respiratory event. Since respiratory events are characteristic of maternal SDB, this raises the possibility that SDB may influence fetal well-being.

Lower, Variable Intrathecal Opioid Doses, and the Incidence of Prolonged Fetal Heart Rate Decelerations After Combined Spinal Epidural Analgesia for Labor: A Quality Improvement Analysis.

BackgroundCombined spinal-epidurals with low-dose intrathecal opioids and local anesthetics are commonly used to initiate labor analgesia due to the fast onset of analgesia and good patient satisfaction. Intrathecal fentanyl has been associated with fetal bradycardia, and the rate may be higher at doses of 25 mcg and above. As such, our institution limits intrathecal fentanyl doses to less than 15 mcg for labor. Prompted by a few incidents of prolonged fetal bradycardia at even these low doses, we sought to audit the side effects associated with varying low doses of intrathecal fentanyl.MethodsAfter IRB approval, a retrospective review was performed on 555 labor records from May–December, 2016. All the patients received combined spinal epidurals for labor analgesia. Intrathecal medication consisted of 1 mL of 0.25% bupivacaine, and varying fentanyl doses: 2.5, 5, 10, and 15 mcg. The incidences of prolonged fetal heart rate decelerations, emergent cesarean delivery, magnitude of pain reduction, pruritus requiring treatment, and hypotension were compared.ResultsDemographic variables were equivalent between the groups. There were no differences in the rates of prolonged fetal decelerations (in order of increasing fentanyl dose: 4.4%, 2.3%, 7.6%, 3.0%, p-value = 0.11), emergent cesarean delivery, magnitude of pain reduction, pruritus, or maternal hypotension.ConclusionsIn conclusion, the rates of prolonged fetal heart rate decelerations after combined spinal epidural with intrathecal bupivacaine and fentanyl does not differ for fentanyl doses of 15 mcg and below.

Prolonged Fetal Heart Rate Decelerations in Labor: Can We Reduce Unplanned Primary Cesarean Sections in This Group?

Non-reassuring fetal tracing is the second leading cause of primary cesarean delivery in the United States. Prolonged fetal heart rate decelerations are non-reassuring fetal heart rate characteristics, which do not uniformly predict poor fetal outcome but can prompt obstetricians to proceed with cesarean delivery. The objective of this manuscript is to identify a strategy to reduce the primary cesarean section rate in patients with prolonged fetal heart rate decelerations in labor. This is a retrospective cohort study over a 5-year period at an academic medical center, including patients undergoing primary cesarean section following labor induction, augmentation, or spontaneous labor who were noted to have prolonged fetal heart rate deceleration(s) in the 1h prior to the time of delivery. Two groups were compared: "crash" cesarean sections versus "emergent" cesarean sections. The primary outcome was if fetal heart tones were rechecked in the operating room prior to cesarean section incision. Secondary outcomes included maternal-fetal monitoring versus Doppler fetal heart tones in the operating room, return to baseline noted in the operating room, fetal outcomes, fetal monitoring characteristics, and anesthesia type between crash versus emergent groups. Of 1969 term singleton cesarean sections, 119 patients met our inclusion criteria (emergent group n = 80) (crash group n = 39), which accounted for 13.9% of all primary cesarean sections during the study period. The emergent group had a significantly higher rate of reassessment of fetal heart tones in the operating room n = 61 (76.2%) versus the crash group n = 15 (38.4%) (p ≤ 0.0001). There were no statistically significant differences regarding fetal outcomes between the two groups. The crash group had a higher rate of category 1 fetal heart rate tracing prior to the prolonged deceleration, a longer median prolonged deceleration, and a deeper median nadir of the prolonged deceleration; these differences were statistically significant. The prolonged-to-delivery interval was significantly shorter in the crash group (median = 15min) than tin he emergent group (median = 33min) (p ≤ 0.0001). The crash group also had a higher rate of general anesthesia (n = 11, 28.2%) than the emergent group (n = 6, 7.5%) (p = 0.002). The crash group was specifically investigated. Of the 15 patients with fetal heart tones rechecked in the crash group, 7 had returned to baseline in the operating room, but underwent cesarean section without fetal monitoring. Our results indicate that the practice of placing patients on fetal monitor upon arrival to the operating room prior to performing crash cesarean delivery could reduce the rate of primary cesarean deliveries performed for prolonged decelerations in labor. When fetal heart tones have returned to baseline upon arrival in the operating room, the decision to proceed with cesarean delivery can be reconsidered. However, many clinical factors must be taken into consideration, and the decision to proceed is ultimately at the discretion of the obstetrics provider.

Correlation of prolonged fetal heart rate decelerations and perinatal outcome among patients undergoing emergency cesarean section: Implication to standardizing management and notification guidelines

Introduction: A prolonged fetal heart rate (FHR) decelerations reflects as a danger signal in relation to perinatal outcome.

Case 1: An Infant with Arm Swelling and Nodules

A male neonate is born via spontaneous vaginal delivery to a 28-year-old primiparous woman at 39 2/7 weeks of gestation after an uncomplicated pregnancy. Labor is complicated by prolonged fetal heart rate decelerations, but the mother declines a cesarean section and vacuum extraction is initially unsuccessful. At birth the neonate is apneic but maintains a heart rate greater than 100 beats/min throughout the resuscitation. He requires intubation for persistent apnea 4 minutes after birth. His Apgar scores are 2, 3, 5, and 5 at 1, 5, 10, and 20 minutes, respectively. His physical examination on admission to the NICU is significant for diffuse hypotonia, lethargy, and absence of primitive reflexes. His arterial blood gas measurement 1.5 hours after birth shows a pH of 7.32, Pco2 of 32 mm Hg, and base deficit of 9. A blood culture specimen is collected and he starts empiric treatment with ampicillin and gentamicin. The infant is transferred to a tertiary care NICU for therapeutic hypothermia and has moderate encephalopathy on admission. He has a fluctuant, boggy mass over his occipital skull and undergoes noncontrast head computed tomography, which shows a large subgaleal hemorrhage, skull fracture, and small ventricles concerning for cerebral edema. A significant drop in his hematocrit is noted, and he receives transfusions of packed red blood cells and fresh frozen plasma. He requires a dopamine infusion and stress-dose hydrocortisone to maintain age-appropriate blood pressures. Electroencephalography (EEG) shows electrographic and clinical seizure activity, which is …

Maternal Pulse Pressure at Admission is a Risk Factor for Fetal Heart Rate Changes After Initial Dosing of a Labor Epidural

Objective To examine low maternal admission pulse pressure (PP) as a risk factor for new onset postepidural fetal heart rate (FHR) abnormalities. Study Design Retrospective cohort study of nulliparous, singleton, vertex-presenting women admitted to labor and delivery after 37 0/7 weeks that received an epidural during labor. Women with a low admission PP were compared with those with a normal admission PP. The primary outcome was new onset FHR abnormalities defined as recurrent late or prolonged FHR decelerations in the first hour after initial dosing of a labor epidural. Results New onset FHR abnormalities, defined as recurrent late decelerations and/or prolonged decelerations, occurred in 6% of subjects in the normal PP cohort compared with 27% in the low PP cohort (odds ratio, 5.6; 95% confidence interval, 2.1–14.3; P P Conclusion New onset FHR abnormalities after initial labor epidural dosing occur more frequently in women with a low admission PP than those with a normal admission pulse. Admission PP appears to be a novel predictor of new onset postepidural FHR abnormalities.

Effects of Maternal Obstructive Sleep Apnoea on Fetal Growth: A Prospective Cohort Study

ObjectiveThe objective of this study is to determine whether obstructive sleep apnea (OSA) is associated with reduced fetal growth, and whether nocturnal oxygen desaturation precipitates acute fetal heart rate changes.Study DesignWe performed a prospective observational study, screening 371 women in the second trimester for OSA symptoms. 41 subsequently underwent overnight sleep studies to diagnose OSA. Third trimester fetal growth was assessed using ultrasound. Fetal heart rate monitoring accompanied the sleep study. Cord blood was taken at delivery, to measure key regulators of fetal growth.ResultsOf 371 women screened, 108 (29%) were high risk for OSA. 26 high risk and 15 low risk women completed the longitudinal study; 14 had confirmed OSA (cases), and 27 were controls. The median (interquartile range) respiratory disturbance index (number of apnoeas, hypopnoeas or respiratory related arousals/hour of sleep) was 7.9 (6.1–13.8) for cases and 2.2 (1.3–3.5) for controls (p<0.001). Impaired fetal growth was observed in 43% (6/14) of cases, vs 11% (3/27) of controls (RR 2.67; 1.25–5.7; p = 0.04). Using logistic regression, only OSA (OR 6; 1.2–29.7, p = 0.03) and body mass index (OR 2.52; 1.09–5.80, p = 0.03) were significantly associated with impaired fetal growth. After adjusting for body mass index on multivariate analysis, the association between OSA and impaired fetal growth was not appreciably altered (OR 5.3; 0.93–30.34, p = 0.06), although just failed to achieve statistical significance. Prolonged fetal heart rate decelerations accompanied nocturnal oxygen desaturation in one fetus, subsequently found to be severely growth restricted. Fetal growth regulators showed changes in the expected direction- with IGF-1 lower, and IGFBP-1 and IGFBP-2 higher- in the cord blood of infants of cases vs controls, although were not significantly different.ConclusionOSA may be associated with reduced fetal growth in late pregnancy. Further evaluation is warranted to establish whether OSA may be an important contributor to adverse perinatal outcome, including stillbirth.

Maternal pulse pressure at admission is a risk factor for fetal heart rate changes after initial dosing of a labor epidural: a retrospective cohort study

To examine low maternal admission pulse pressure (PP) as a risk factor for new onset postepidural fetal heart rate (FHR) abnormalities. Retrospective cohort study of nulliparous, singleton, vertex-presenting women admitted to labor and delivery after 37 0/7 weeks that received an epidural during labor. Women with a low admission PP were compared with those with a normal admission PP. The primary outcome was new onset FHR abnormalities defined as recurrent late or prolonged FHR decelerations in the first hour after initial dosing of a labor epidural. New onset FHR abnormalities, defined as recurrent late decelerations and/or prolonged decelerations, occurred in 6% of subjects in the normal PP cohort compared with 27% in the low PP cohort (odds ratio, 5.6; 95% confidence interval, 2.1-14.3; P < .001). A multivariate logistic regression analysis generated an adjusted odds ratio of 28.9 (95% confidence interval, 3.7-221.4; P < .001). New onset FHR abnormalities after initial labor epidural dosing occur more frequently in women with a low admission PP than those with a normal admission pulse. Admission PP appears to be a novel predictor of new onset postepidural FHR abnormalities.

Impact of morbid obesity on epidural anesthesia complications in labor

We sought to determine whether morbid obesity is associated with increased maternal hypotension or fetal heart rate (FHR) abnormalities after epidural anesthesia placement during labor. This was a retrospective cohort study of women undergoing epidural anesthesia during labor at term from April 2008 through July 2010. A total of 125 morbidly obese patients were matched for age and race with 125 normal-weight patients. Morbidly obese patients had more frequent persistent systolic (16% vs 4%, P = .003) and diastolic (49% vs 29%, P = .002) hypotension and more prolonged (16% vs 5%, P = .006) and late (26% vs 14%, P = .03) FHR decelerations. Increasing body mass index was associated with persistent systolic (odds ratio, 1.06; 95% confidence interval, 1.02-1.10) and diastolic (odds ratio, 1.04; 95% confidence interval, 1.01-1.06) hypotension after controlling for epidural bolus dose and hypertensive disorders. Morbidly obese women have more hypotension and prolonged FHR decelerations following epidural anesthesia during labor at term.

313: Impact of morbid obesity on epidural anesthesia complications in labor

313: Impact of morbid obesity on epidural anesthesia complications in labor

Anaphylactoid syndrome of pregnancy immediately after intrauterine pressure catheter placement

A 35-year-old multipara woman underwent intrauterine pressure catheter placement during labor. Immediately afterwards, she had severe dyspnea develop, became unresponsive, and had a prolonged fetal bradycardia. During emergency cesarean section, she required cardiopulmonary resuscitation repetitively. She then had disseminated intravascular coagulopathy develop and underwent hysterectomy. Anaphylactic reaction may be associated with intrauterine pressure catheter placement.

Atypical ductus venosus blood flow pattern during a prolonged fetal heart rate deceleration in labor

Atypical ductus venosus blood flow pattern during a prolonged fetal heart rate deceleration in labor

Predicting Prolonged Fetal Heart Rate Deceleration following Intrathecal Fentanyl/Bupivacaine

Predicting Prolonged Fetal Heart Rate Deceleration following Intrathecal Fentanyl/Bupivacaine

Predicting prolonged fetal heart rate deceleration following intrathecal fentanyl/bupivacaine

Intrathecal opioids for labor analgesia are occasionally associated with fetal heart rate abnormalities. We wanted to identify risk factors for this occurrence. The fetal tracings of 151 consecutive patients were reviewed for the period including 30 min before and 60 min after combined spinal-epidural analgesia using intrathecal bupivacaine with fentanyl. Their progress of labor at injection was also recorded. Lack of fetal head engagement (odds ratio 5.5, 95% CI 2.1-14.2) and the presence of variable fetal heart rate decelerations (odds ratio 3.6, 95% CI 1.6-8.4) were associated with prolonged fetal heart rate deceleration after combined spinal-epidural analgesia. This case-control study suggests that if the fetal head is not engaged or if the fetus is experiencing variable decelerations, there is an increased risk of prolonged fetal heart rate deceleration following intrathecal fentanyl/bupivacaine. This finding must now be confirmed in a cohort study.

The relationship between amniotic fluid index and successful external cephalic version: a 14-year experience

Objective This study was undertaken to assess the association between amniotic fluid index (AFI), success of external cephalic version (ECV), and obstetric outcome in patients undergoing ECV. Study design A prospective observational study was performed that included all patients who had a trial of ECV from 1987 to 2000 in our center. Rates of success, fetal heart decelerations during trial at ECV, and cesarean deliveries were calculated. Groups were divided by an AFI performed immediately before ECV: AFI less than 10 cm, 10 to 15 cm, and more than 15 cm. Results In our group of 1361 patients undergoing ECV, the rate of success was related to the AFI in both parous women (49.1%, 63.5% and 72.1% [ P<.001] for each AFI group, respectively) and nulliparous women (36.5%, 43.6%, and 57.3% [ P<.001]). The rate of cesarean section delivery was related to AFI in nulliparous but not multiparous patients ( P<.001). The rate of prolonged fetal heart rate decelerations was not significantly related to the AFI. Conclusion The rate of successful ECV and cesarean section deliveries is related to the amniotic fluid volume. This information may be used to consent patient before a trial of ECV.

Fetal heart rate patterns in 423 brain-damaged infants: an update

Objective: To update our experience with the fetal heart rate (FHR) pattern of singleton term brain-damaged infants. Methods: The FHR patterns of 123 singleton term brain-damaged infants were retrospectively analyzed and compared with 300 previously published cases. Results: For these 423 cases, obstetrical care was provided from 1976 to 1998. With the exception of more recent obstetrical care, the additional 123 cases were statistically similar to the previously published 300 cases. Overall, the admission FHR patterns were reactive: 229 (54%); nonreactive: 175 (41%); bradycardic: 10 (3%); or unclassifiable: 9 (2%). In the reactive group, the FHR did the following: 1) remained reactive: 29 (13%); 2) developed an elevated baseline in association with repetitive decelerations: 107 (47%); or 3) exhibited a sudden prolonged FHR deceleration that lasted until delivery: 93 (40%). In the nonreactive group, the FHR pattern remained nonreactive at a similar baseline rate: 125 (71%); developed a progressive bradycardia: 32 (18%); or developed a prolonged deceleration that lasted until delivery: 18 (10%). Conclusion: Our retrospective review of 123 additional cases continues to demonstrate that brain-damaged fetuses manifest distinctly similar intrapartum FHR patterns that easily can be categorized and identified on the basis of the fetal admission test and subsequent changes in the baseline rate. This distinction, which covers a 22-year period, would appear to be helpful in the management of obstetrical patients in labor.

Does the onset of neonatal seizures correlate with the timing of fetal neurologic injury?

The onset of seizures after birth has been considered evidence of an intrapartum asphyxial event. The present study was undertaken to determine whether the timing of neonatal seizures after birth correlated with the timing of a fetal asphyxial event. Thus, singleton term infants diagnosed with hypoxic ischemic encephalopathy and permanent brain injury had a mean birth to seizure onset interval of 9.8 +/- 17.7 (range 1-90) hours. When these infants were categorized according to their fetal heart rate (FHR) patterns, the acute group (normal FHR followed by a sudden prolonged FHR deceleration that continued until delivery) tended to have earlier seizures than infants did within the tachycardia group (normal FHR followed by tachycardia, repetitive decelerations, and diminished variability) and the preadmission group (persistent nonreactive FHR pattern intrapartum). These seizure intervals were as follows: acute, 6.6 +/- 18.0 (range 1-90) hours; tachycardia, 11.1 +/- 17.1 (range 1-61) hours; and preadmission, 11.8 +/- 17.9 (range 1-79) hours (p < 0.05). But the range varied widely and no group was categorically distinct. In conclusion, the onset of neonatal seizures after birth does not, in and of itself, appear to be a reliable indicator of the timing of fetal neurologic injury.

The fetal admission test and intrapartum fetal death.

Our objective was to describe the admission and subsequent intrapartum fetal heart rate (FHR) patterns in 21 singleton term pregnancies with an intrapartum fetal death. Through a retrospective chart review, 21 pregnancies with a term intrapartum fetal death were divided into 2 groups based on the fetal admission test (FAT): Group I-reactive (one or more FHR accelerations of 15 bpm x 15 sec in the first 30 min of monitoring); and Group II-nonreactive (NR [the absence of accelerations]). The FAT was compared with the subsequent intrapartum FHR pattern. Of the 21 deaths, the FAT was reactive in 7 fetuses (33%) or NR in 14 fetuses (67%). While the demographic features of these groups were statistically similar, Group II had higher rates of meconium (12 out of 14 (86%) vs. 2 out of 7 [29%] p = 0.017) and admission FHR decelerations (9 out of 14 (64%) vs. 1 out of 7 [14%] p = 0.06). In Group I, a sudden catastrophic event such as a uterine rupture produced a prolonged FHR deceleration in six fetuses (86%). One (14%) fetus died after a Hon pattern. In Group II, four patients had a stair steps to death pattern. Intrapartum fetal death can occur after a reactive or NR FAT. With a reactive FAT, a catastrophic event appears necessary to cause fetal death. The higher rates of meconium, FHR decelerations, and stair steps to death patterns in the NR group suggest the underlying basis for the fetal demise was related to preadmission fetal compromise.

Neonatal Nucleated Red Blood Cell and Lymphocyte Counts in Fetal Brain Injury

Objective: To determine whether neonatal lymphocyte or nucleated red blood cell (RBC) counts can be used to date fetal neurologic injury.Methods: Singleton, term infants with hypoxic-ischemic encephalopathy, permanent neurologic impairment, and sufficient laboratory data were divided into two groups: infants with preadmission injury, manifested by a nonreactive fetal heart rate (FHR) pattern from admission until delivery; and infants with acute injury, manifested by a normal FHR pattern followed by a sudden prolonged FHR deceleration. Lymphocyte and nucleated RBC values were compared with published high normal counts for normal neonates: 8000 lymphocytes/mm3 and 2000 nucleated RBCs/mm3.Results: The study population consisted of 101 neonates. In the first hours of life, lymphocyte counts were elevated among injured newborns, and then the counts rapidly normalized. Brain-injured neonates were 25 times more likely to have a lymphocyte count greater than 8000 than were normal neonates (54 [62%] of 87 versus 6 [7%] of 84; odds ratio 25.5; 95% confidence interval 8.8, 80.1; P < .001). The mean lymphocyte count tended to be higher in the preadmission-injury group than in the acute-injury group. In comparison, nucleated RBC values were not correlated as strongly with neonatal hours of life; nucleated RBC counts tended to be higher and persist longer among neonates with preadmission injury than among those with acute injury.Conclusion: Compared with normal levels, both lymphocyte and nucleated RBC counts were elevated among neonates with fetal asphyxial injury. Both counts appear to be more elevated and to remain elevated longer in newborns with preadmission injury than in infants with acute injury. However, the rapid normalization of lymphocyte counts in these injured neonates limits the clinical usefulness of these counts after the first several hours of life.

Uterine rupture during trial of labor after previous cesarean section

This study was undertaken to determine the incidence and associations of uterine rupture and dehiscence with an attempted vaginal birth after cesarean.section. The charts from 137 patients who had uterine scar separation after a previous cesarean section from 1983 to 1989 were examined. Approximately 9.3% of the 119,395 women who were delivered in that interval had a prior cesarean section. Of those, 68.8% underwent a trial of labor with a 79.2% success rate. The uterine rupture rate in this latter group was 0.8%, while an additional 0.7% had a bloodless dehiscence. Bleeding and pain were unlikely findings with a uterine scar separation (3.4% and 7.6%, respectively). The most common manifestation of a scar separation was a prolonged fetal heart rate deceleration leading to operative intervention (70.3%). We conclude that, although the incidence of uterine rupture was low, the event is most often seen as an acute emergency. Prevention should be directed toward timely diagnosis and prompt management of labor dystocias. Staff and facilities for safe management of a uterine scar separation are a requisite for the conduct of a vaginal birth after previous cesarean section.