Outcome of resuscitated apparently stillborn infants: a ten year review

[Perinatal risk factors for the occurrence of singleton apparently stillborn infants]

OBJECTIVES

To identify the perinatal risk factors for the occurrence of singleton apparently stillborn infants.

METHODS

This was a case-control study. A total of 154 singleton neonates with gestational age ≥28 weeks and Apgar score of 0-1 who were subsequently successfully resuscitated in the Obstetrics and Gynecology Hospital of Fudan University from January 2006 to December 2015 were enrolled as the case group (apparently stillborn group). A total of 616 singleton infants born from January 2006 to December 2015 (1-minute Apgar score >1) were randomly selected in a 1:4 ratio as the control group. Univariate analysis and multivariate logistic regression were used to analyze the perinatal risk factors for the occurrence of apparently stillborn infants.

RESULTS

The gestational age and birth weight in the apparently stillborn group were significantly lower than those in the control group (P<0.05). The incidences of fetal hydrops, cord prolapse, grade III meconium-stained amniotic fluid, placental abruption, breech presentation, severe pre-eclampsia, maternal general anesthesia at delivery, abnormal antenatal fetal heart monitoring and decreased fetal movement were significantly higher in the apparently stillborn group than those in the control group (P<0.05). The multivariate logistic analysis showed that the mother had general anesthesia at delivery (OR=34.520), decreased antenatal fetal movement (OR=28.168),placental abruption (OR=15.641), grade III meconium-stained amniotic fluid (OR=6.365), abnormal antenatal fetal heart monitoring (OR=5.739), and breech presentation (OR=2.614) were risk factors for the occurrence of apparently stillborn infants (P<0.05), while higher gestational age was a protective factor (OR=0.686, P<0.05).

CONCLUSIONS

Attention needs to be paid to mothers with abnormal prenatal fetal heart monitoring, decreased fetal movement, preterm labor, placental abruption, breech presentation, grade III meconium-stained amniotic fluid, and general anesthesia. Preparations for resuscitation should be done to rescue apparently stillborn infants.

Placental pathology of resuscitated apparent stillbirth

Resuscitated apparent stillbirth (RAS) is defined as an infant with APGAR scores of 0 at 1 minute of life who receives successful resuscitation. Assessment of placental pathology is considered standard of care in such infants, but the clinical significance of these placental findings as they relate to clinical outcomes has yet to be described within the literature. We report the findings of a retrospective study of placental pathology as defined by the Amsterdam and Dublin criteria of RAS infants born in South Australia over an 8-year period. The aim of this study was to assess whether placental pathology was able to predict RAS clinical outcomes of death, survival with adverse neurological outcomes, and survival with normal neurological outcomes. The RAS cohort within our study is small, reflecting the low incidence of RAS. Of the 25 RAS subjects 16 survived, five with abnormal neurological outcomes and 11 with normal neurological outcomes. No statistically significant difference was seen between the clinical outcome groups in the incidence of specific macroscopic and microscopic placental findings. No sentinel lesion was seen in any one clinical outcome group. Relevant placental pathology was found in all but one subject validating the role of placental pathology in determination of the aetiology of RAS. The most common finding was maternal vascular malperfusion. Placental pathology in RAS infants remains relevant but is unable to contribute to the matrix of predictive information available to the clinician and family.

Improving infant outcome with a 10 min Apgar of 0

OBJECTIVE

Asystole at birth and extending through 10 min is rare, with current international recommendations stating it may be appropriate to consider discontinuation of resuscitation in this clinical scenario. These recommendations are based on small case series of both term and preterm infants, where death or abnormal outcome was nearly universal. Study objective was to determine recent outcome of infants with an Apgar score of 0 at 10 min despite cardiopulmonary resuscitation, treated with therapeutic hypothermia or standard treatment, in randomised cooling studies.

DESIGN

Outcome studies of infants with an Apgar of 0 at 10 min subsequently resuscitated and treated with hypothermia or standard treatment were reviewed and combined with local outcome data of infants treated with hypothermia.

RESULTS

Four recent studies (n=81) and local data (n=9) yielded a total of 90 infants with an Apgar of 0 at 10 min, with 56 treated with hypothermia and 34 controls. Primary outcome of death or abnormal neurodevelopmental outcome (18-24 months) occurred in 73% cooled and 79.5% normothermic infants (p=0.61).

IMPLICATIONS

Although poor, the outcome for infants with an Apgar of 0 at 10 min of life has improved substantially in recent years. This may be related to treatment with hypothermia, enhanced resuscitation techniques and/or other supportive management. Current recommendations to consider discontinuation of resuscitation without a detectable heart rate at 10 min should consider these findings.

Status epilepticus after prolonged umbilical cord occlusion is associated with greater neural injury in [corrected] fetal sheep at term-equivalent

The majority of pre-clinical studies of hypoxic-ischemic encephalopathy at term-equivalent have focused on either relatively mild insults, or on functional paradigms of cerebral ischemia or hypoxia-ischemia/hypotension. There is surprisingly little information on the responses to single, severe ‘physiological’ insults. In this study we examined the evolution and pattern of neural injury after prolonged umbilical cord occlusion (UCO). 36 chronically instrumented fetal sheep at 125–129 days gestational age (term = 147 days) were subjected to either UCO until mean arterial pressure was < = 8 mmHg (n = 29), or sham occlusion (n = 7). Surviving fetuses were killed after 72 hours for histopathologic assessment with acid-fuchsin thionine. After UCO, 11 fetuses died with intractable hypotension and 5 ewes entered labor and were euthanized. The remaining 13 fetuses showed marked EEG suppression followed by evolving seizures starting at 5.8 (6.8) hours (median (interquartile range)). 6 of 13 developed status epilepticus, which was associated with a transient secondary increase in cortical impedance (a measure of cytotoxic edema, p<0.05). All fetuses showed moderate to severe neuronal loss in the hippocampus and the basal ganglia but mild cortical cell loss (p<0.05 vs sham occlusion). Status epilepticus was associated with more severe terminal hypotension (p<0.05) and subsequently, greater neuronal loss (p<0.05). In conclusion, profound UCO in term-equivalent fetal sheep was associated with delayed seizures, secondary cytotoxic edema, and subcortical injury, consistent with the predominant pattern after peripartum sentinel events at term. It is unclear whether status epilepticus exacerbated cortical injury or was simply a reflection of a longer duration of asphyxia.

Intrapartum-related neonatal encephalopathy incidence and impairment at regional and global levels for 2010 with trends from 1990

BACKGROUND

Intrapartum hypoxic events ("birth asphyxia") may result in stillbirth, neonatal or postneonatal mortality, and impairment. Systematic morbidity estimates for the burden of impairment outcomes are currently limited. Neonatal encephalopathy (NE) following an intrapartum hypoxic event is a strong predictor of long-term impairment.

METHODS

Linear regression modeling was conducted on data identified through systematic reviews to estimate NE incidence and time trends for 184 countries. Meta-analyses were undertaken to estimate the risk of NE by sex of the newborn, neonatal case fatality rate, and impairment risk. A compartmental model estimated postneonatal survivors of NE, depending on access to care, and then the proportion of survivors with impairment. Separate modeling for the Global Burden of Disease 2010 (GBD2010) study estimated disability adjusted life years (DALYs), years of life with disability (YLDs), and years of life lost (YLLs) attributed to intrapartum-related events.

RESULTS

In 2010, 1.15 million babies (uncertainty range: 0.89-1.60 million; 8.5 cases per 1,000 live births) were estimated to have developed NE associated with intrapartum events, with 96% born in low- and middle-income countries, as compared with 1.60 million in 1990 (11.7 cases per 1,000 live births). An estimated 287,000 (181,000-440,000) neonates with NE died in 2010; 233,000 (163,000-342,000) survived with moderate or severe neurodevelopmental impairment; and 181,000 (82,000-319,000) had mild impairment. In GBD2010, intrapartum-related conditions comprised 50.2 million DALYs (2.4% of total) and 6.1 million YLDs.

CONCLUSION

Intrapartum-related conditions are a large global burden, mostly due to high mortality in low-income countries. Universal coverage of obstetric care and neonatal resuscitation would prevent most of these deaths and disabilities. Rates of impairment are highest in middle-income countries where neonatal intensive care was more recently introduced, but quality may be poor. In settings without neonatal intensive care, the impairment rate is low due to high mortality, which is relevant for the scale-up of basic neonatal resuscitation.

Chorioamnionitis risk and neonatal outcome in preterm premature rupture of membranes

OBJECTIVE

The objective of this study was to compare the neonatal outcome in patients with preterm premature rupture of membranes with and without clinical chorioamnionitis.

STUDY DESIGN

This is a retrospective study that included 254 pregnant women with preterm rupture of membranes. The study group was divided according to the presence or absence of clinical chorioamnionitis defined as the presence of two or more of the following criteria: maternal temperature >38 degrees C on two or more occasions > or =1 h apart, maternal tachycardia (> or =120 beats/min), uterine tenderness, foul smelling amniotic fluid, maternal leukocytosis > or =20,000 mm(-3) with bands and positive C reactive protein. Also the study population was divided according to the use of tocolysis. Exclusion criteria included multiple pregnancy, fetal congenital anomalies, diabetes mellitus and severe preeclampsia. Amniotic fluid was collected from the cervix or from the transabdominal amniocentesis. Antibiotics and tocolysis were used according to the hospital protocols. Parametric and nonparametric statistics were used for comparisons.

RESULTS

There were no significant differences in birth weight, Apgar scores at 1 and 5 min, rates of respiratory distress syndrome, intraventricular hemorrhage and necrotizing enterocolitis between patients with and without clinical chorioamnionitis or between women who received tocolysis and the ones that did not receive tocolysis. In cases of clinical chorioamnionitis and when tocolysis was used the neonates stayed longer in the neonatal intensive care unit (NICU).

CONCLUSION

Patients with preterm premature rupture of membranes and clinical chorioamnionitis have similar neonatal outcomes than the ones without clinical chorioamnionitis.

Resuscitation beyond 10 minutes of term babies born without signs of life

OBJECTIVE

To obtain population-based data on babies who were admitted to a neonatal intensive care unit despite having Apgar scores of 0 up to and including 10 min, and to document their outcomes. We aimed also to review other studies where outcomes following a 10-min Apgar score of 0 were described, and to combine them with own results. Current recommendations regarding the discontinuation of resuscitation will be reconsidered in light of these results.

METHODS

In order to obtain population-based data for babies born in New South Wales (NSW), a request was made to the NSW Neonatal Intensive Care Unit Study (NICUS) directors to allow identification of babies in the NICUS database with Apgar scores of 0 at both 1 and 5 minutes. Individual directors were then asked to determine from their hospital records, which of these babies had a 10-minute Apgar of 0, and to provide the results of follow-up assessments of any survivors in this subgroup.

RESULTS

Twenty-nine full-term newborns with a 10-minute Apgar score of 0 were identified. Twenty of the 29 babies died before leaving hospital. Of the 9 who were discharged alive, eight had severe disability and one had moderate disability. Thus death or severe disability occurred in 28/29 (97%), and death or any disability in 100%. Combining with other published studies, death or severe disability occurred in 63/64 (98%).

CONCLUSION

The above findings strongly support the discontinuation of resuscitation if a baby remains asystolic at 10 minutes.

Neonatal resuscitation guidelines 2000: framework for practice

Based on extensive evaluation of the existing evidence and consensus development, there are new recommendations in the Neonatal Resuscitation Program (NRP) guidelines 2000. These guidelines are described along with a brief review of the supporting evidence. The goal is to establish a framework for practice of neonatal resuscitation with a more scientific, evidence-based approach.

Ethical considerations in neonatal resuscitation: clinical and research issues

The recent publication of guidelines for ethical decision making for resuscitation of infants has highlighted the problems inherent in using the currently available data to define those situations in which resuscitation should be or might be withheld or withdrawn. Prior selection criteria for resuscitation, criteria for inclusion into the study group, incomplete resuscitation, gestational age determination, intrauterine growth restriction, subjective assessment of 'poor' outcome, and other factors make setting specific parameters for acting or not acting difficult, if not dangerous, and possibly impossible. Research in neonatal resuscitation poses some potential ethical obstacles, but national and international regulations and guidelines are available to assist investigators in study design.

International Guidelines for Neonatal Resuscitation: An excerpt from the Guidelines 2000 for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care: International Consensus on Science. Contributors and Reviewers for the Neonatal Resuscitation Guidelines

The International Guidelines 2000 Conference on Cardiopulmonary Resuscitation (CPR) and Emergency Cardiac Care (ECC) formulated new evidenced-based recommendations for neonatal resuscitation. These guidelines comprehensively update the last recommendations, published in 1992 after the Fifth National Conference on CPR and ECC. As a result of the evidence evaluation process, significant changes occurred in the recommended management routines for: * Meconium-stained amniotic fluid: If the newly born infant has absent or depressed respirations, heart rate <100 beats per minute (bpm), or poor muscle tone, direct tracheal suctioning should be performed to remove meconium from the airway. * Preventing heat loss: Hyperthermia should be avoided. * Oxygenation and ventilation: 100% oxygen is recommended for assisted ventilation; however, if supplemental oxygen is unavailable, positive-pressure ventilation should be initiated with room air. The laryngeal mask airway may serve as an effective alternative for establishing an airway if bag-mask ventilation is ineffective or attempts at intubation have failed. Exhaled CO(2) detection can be useful in the secondary confirmation of endotracheal intubation. * Chest compressions: Compressions should be administered if the heart rate is absent or remains <60 bpm despite adequate assisted ventilation for 30 seconds. The 2-thumb, encircling-hands method of chest compression is preferred, with a depth of compression one third the anterior-posterior diameter of the chest and sufficient to generate a palpable pulse. * Medications, volume expansion, and vascular access: Epinephrine in a dose of 0.01-0.03 mg/kg (0.1-0.3 mL/kg of 1:10,000 solution) should be administered if the heart rate remains <60 bpm after a minimum of 30 seconds of adequate ventilation and chest compressions. Emergency volume expansion may be accomplished with an isotonic crystalloid solution or O-negative red blood cells; albumin-containing solutions are no longer the fluid of choice for initial volume expansion. Intraosseous access can serve as an alternative route for medications/volume expansion if umbilical or other direct venous access is not readily available. * Noninitiation and discontinuation of resuscitation: There are circumstances (relating to gestational age, birth weight, known underlying condition, lack of response to interventions) in which noninitiation or discontinuation of resuscitation in the delivery room may be appropriate.

Outcome after successful resuscitation of babies born with apgar scores of 0 at both 1 and 5 minutes

OBJECTIVE

Our purpose was to evaluate the outcome of infants who underwent successful resuscitation after initial Apgar scores of 0 at both 1 and 5 minutes.

STUDY DESIGN

Eligible infants were identified through the perinatal database at the University of Tennessee, Memphis. Hospital records and long-term outcomes, where available, of babies who met the above criteria occurring between January 1986 and February 1999 were reviewed.

RESULTS

Thirty-three of 81,603 infants (0.4/1000 births) met our study criteria. Twenty-two (67%) babies died during hospitalization. Mortality decreased significantly from 100% for babies with a birth weight of <750 g to 38% for those weighing > or =2500 g at birth (P =.03). All 6 babies delivered before 26 weeks' gestation died. The incidence of 10-minute Apgar scores >0 was significantly higher among survivors than among those who subsequently died (82% vs 33%, P <.05). Nine survivors had hypoxic-ischemic encephalopathy diagnosed before discharge. Of the 7 infants with available follow-up, 4 had significant persisting morbidity. Two infants had normal neurologic examinations at follow-up.

CONCLUSION

Survival in babies born with 1- and 5-minute Apgar scores of 0 is predicted by birth weight, gestational age, and 10-minute Apgar score. Long-term sequelae are common but not ensured.

Newborn assessment and long-term adverse outcome: a systematic review

The medical literature was searched for publications between 1966 and September 1997 for data on the association of Apgar score, umbilical blood pH, or Sarnat grading of encephalopathy with long-term adverse outcome. Odds ratios for these associations were combined to calculate common odds ratios with 95% confidence intervals. Our search identified abstracts of 1312 studies and 81 articles with sufficient numeric data to formulate contingency tables. Forty-two of these qualified for inclusion in our meta-analysis. The strongest associations in the prediction of neonatal death were found by comparing umbilical artery pH <7 with pH >/=7 (common odds ratio 43; 95% confidence interval 15-124) and by comparing Sarnat grade III with grade II (common odds ratio 24; 95% confidence interval 13-45). In the prediction of cerebral palsy, the strongest associations were found for Sarnat grade III versus grade II (common odds ratio 20; 95% confidence interval 6-70) and for 20-minute Apgar score 0 to 3 versus 4 to 6 (common odds ratio 15; 95% confidence interval 5-50).

Mortality and neurodevelopmental outcome for infants receiving adrenaline in neonatal resuscitation

OBJECTIVE

To document the outcome, in terms of mortality and morbidity, for all infants requiring adrenaline as part of initial neonatal resuscitation, and to identify the differences between term and preterm infants.

METHODS

All infants in a five-year period who received adrenaline during delivery room resuscitation were retrospectively identified. Data from the perinatal period were ascertained by chart review. Details of survivors at 1 year or later were reviewed.

RESULTS

Seventy-eight infants were identified representing 0.2% of all deliveries. Over half of all infants survived, with the proportion increasing with advancing gestational age from 30% below 29 weeks to 67% at term. Seventy-three per cent of survivors were normal at follow-up to at least 1 year, with more preterm infants being normal than term infants (79% vs. 64%). Over half of survivors below 29 weeks' gestation were normal, but overall 78% of this group either died or showed evidence of neurodevelopmental disability. Asystolic infants did not differ from the bradycardic infants in terms of survival or rates of disability. Adrenaline may be contraindicated in asystolic very preterm infants.

CONCLUSIONS

Adrenaline retains a role in term and mature preterm infants where there is an acute cause for depression at delivery. In very preterm infants its use is associated with a high rate of death and disability. Failure to stabilise with adequate ventilatory support should be seen as a poor prognostic sign in this group.

Outcome of resuscitation following unexpected apparent stillbirth

There are few data to inform a decision to resuscitate babies who are unexpectedly stillborn. The outcome for 42 successfully resuscitated stillborn children, of whom 62% survived to be discharged home, is reported. Of the survivors, a poor outcome with severe disability was found in 23% (including one postneonatal death), equivocal outcome was found in 15% (two mild hypertonia; two with mild hemiplegia and no associated other disability) and 62% were free of any impairment at follow up 20 months to 8 years later. In 39 (93%) fetal problems had been identified and the resuscitation team was present at delivery. Poor outcome was associated with late return of heart beat, delayed respirations, neonatal acidaemia and early onset of seizures. Of the unexpected apparent stillbirths successfully resuscitated, 52% died or survived severely disabled, 10% had an equivocal outcome, but 36% survived apparently intact. Therefore, vigorous resuscitation is clearly indicated in these circumstances.

Changes in risk factors for hypoxic-ischaemic seizures in term infants

Term infants with seizures and evidence of perinatal asphyxia were prospectively identified in 1 city and 2 time periods: 1978-1981 and 1991. Infants with multiple congenital abnormalities, hypocalcaemia or infection were excluded. Although there was little change in the overall incidence of neonatal seizures between 1978-1981 (1.9 per 1,000) and 1991 (1.78 per 1,000, N.S.) there was a marked reduction in small for dates infants with seizures: 8 of 19 infants in 1978-1981 compared to none of 16 in 1991 (p < 0.005). In contrast, infants > or = 41 weeks continued to show a markedly increased risk for asphyxia (relative risk 4.48, 95% CI: 1.7-12.3). The mechanism of this improved outcome for small for gestational age infants is unknown, but speculatively may be due to improved obstetric monitoring techniques allowing early identification of compromised infants.

Somatosensory evoked potentials predict neurologic outcome in full-term neonates with asphyxia

OBJECTIVE

To investigate the ability of somatosensory evoked potentials (SSEP) to predict neurologic outcome in term neonates with birth asphyxia.

METHODOLOGY

Upper limb SSEP were performed on nine infants of 1-7 weeks of age who had perinatal asphyxia and an encephalopathy still present at 7 days of age. Comparison was made between the cranial ultrasound, electroencephalogram (EEG), SSEP and neurologic outcome at 9-36 months.

RESULTS

Normal SSEP were found in four infants, all of whom were normal on neurologic follow up at 9-12 months. Neonatal EEG performed on two out of four of these infants were also normal, while cerebral oedema was seen on cranial ultrasound in three of the four studies. No SSEP response was seen initially in three infants, all of whom had adverse outcomes (one death, two with spastic diplegia). In contrast, their neonatal EEG had shown normal background rhythms, while two of the three cranial ultrasounds revealed oedema. For two infants the initial SSEP was absent over one hemisphere and just present over the other. Both children were abnormal on follow up at 10-12 months but did not have a hemiparesis.

CONCLUSIONS

Upper limb SSEP appear more sensitive than EEG or cranial ultrasounds in predicting the short term neurologic outcome of neonates with asphyxia.