Management of Meconium-Stained Newborns in the Delivery Room.

The approach to the management of meconium-stained newborns in the delivery room has been changing for over 40 years. The goal is to prevent meconium aspiration syndrome (MAS) and complications related to MAS. For decades, airway obstruction was believed to be a major component of MAS and, consequently, suction maneuvers to remove meconium from the airways were recommended to decrease the frequency and severity of MAS. Initial recommendations were based on observational studies. However, the incidence of MAS and mortality related to MAS has declined since the 1970s, mostly because of a decrease in the number of postterm deliveries. Recently updated guidelines by the American Heart Association and the Neonatal Resuscitation Program have reflected the strength of evidence supporting tracheal intubation and suctioning for nonvigorous, meconium-stained newborns. This article examines practice change since the 1970s in the delivery room management of meconium-stained newborns and evaluates evidence behind the changes.

Does a policy of earlier induction affect labour outcomes in women induced for postmaturity? A retrospective analysis in a tertiary hospital in the North of England.

OBJECTIVES: to investigate whether a change in the management of postmature pregnancy to earlier induction affects the length of labour and the induction process. Secondly, to assess the feasibility of the research process to inform a future larger study. DESIGN: a change in management of postmature pregnancy in an NHS hospital in October 2013, from induction at 42 weeks gestation to induction between 41-42 weeks, provided an opportunity to conduct a retrospective analysis. Pre-existing data from the maternity database and casenotes were collected and primary outcomes analysed using the Mann-Whitney test and the Hodges-Lehman confidence interval for differences in medians. SETTING: a large city based tertiary referral hospital in the North of England. PARTICIPANTS: 125 women induced before the change in policy were compared with 309 women induced after the change. MEASUREMENTS: primary outcomes were length of 1st and 2nd stage of labour, overall length of labour, length of induction to established labour and length of induction to birth. FINDINGS: the median overall length of labour for women induced at 42 weeks was 6.5hours, while for women induced at 41-42 weeks this was 5.2hours. The difference was not statistically significant (p=0.15, 95% CI for median difference -0.27 to 1.93hours) with a small effect size (Pearson's r=-0.08). The median length of induction to birth was 13.6hours for women induced at 42 weeks and 16.5hours for women induced at 41-42 weeks. This difference was also not statistically significant (p=0.14, 95% CI for median difference -7.25 to 1.20hours) with a small effect size (Pearson's r=-0.13). KEY CONCLUSIONS AND IMPLICATIONS FOR PRACTICE: This study demonstrated no statistically significant differences in length of labour and induction following a change in the management of postmature pregnancy to earlier induction. A large study is needed to establish definitively the effects of earlier induction on labour outcomes.

Post-term pregnancy is an independent risk factor for neonatal morbidity even in low-risk singleton pregnancies.

OBJECTIVE: To determine the independent association of post-term pregnancy with neonatal outcome in low-risk newborns. DESIGN: Retrospective cohort. SETTING: Tertiary university-affiliated medical centre. PATIENTS: All newborns of low-risk singleton pregnancies born at 39+0 to 44+0 weeks' gestation over a 5-year period. EXCLUSION CRITERIA: multiple gestation, maternal hypertensive disorder, diabetes or cholestasis, placental abruption or intrapartum fever (>38°C), small for gestational age (<10th centile) and major congenital or chromosomal anomalies. INTERVENTIONS: None. OUTCOME MEASURES: Admission to the neonatal intensive care unit (NICU), hospital length of stay, 5-min Apgar score, birth trauma, respiratory, neurological, metabolic and infectious morbidities and neonatal mortality. The adverse outcome rate was compared among three groups based on gestational age at birth: post-term (≥42+0 weeks), late term (41+0 to 41+6 weeks) and full term (39+0 to 40+6 weeks). RESULTS: Of the 23 524 eligible neonates, 747 (3.2%) were born post-term, 4632 (19.7%) late term and 18 145 (77.1%) full term. Women in the post-term group versus the late-term group had a significantly higher rate of caesarean section (8.9% vs 5.6%, p<0.001) and operative vaginal delivery (9.6% vs 7.4%, p=0.024). Post-term pregnancy versus full-term pregnancy was associated with an increased risk of NICU admission (OR 2.0, 95% CI 1.4 to 2.8), respiratory morbidity (OR 2.2, 95% CI 1.3 to 3.8) and infectious morbidity (OR 1.88, 95% CI 1.32 to 2.69). Post-term pregnancy versus late-term pregnancy was similarly associated with an increased risk of NICU admission (OR 2.0, 95% CI 1.4 to 2.9), respiratory morbidity (OR 2.7, 95% CI 1.5 to 5.0) and infectious morbidity (OR 1.8, 95% CI 1.2 to 2.7) and with hypoglycaemia (OR 2.6, 95% CI 1.2 to 5.4). Post-term delivery was not associated with neonatal mortality. CONCLUSIONS: Post-term pregnancy is an independent risk factor for neonatal morbidity even in low-risk singleton pregnancies.

[Definitions of expected date of delivery and post-term delivery]. / Comment définir la date présumée de l'accouchement et le dépassement de terme ?

The duration of pregnancy is between 280 and 290 days from the first day of the last menstrual period and varies according to the literature, the authors, the calculation methods and the characteristics of women. Assuming that the date of beginning of pregnancy is known, the expected date of delivery varies depending on the length of gestation. Thus, in literature and in obstetric practice, there is no consensus on the definition of expected date of delivery. From a medical point of view, it seems important to fix the date from which the monitoring should start and from which an induction of labour should be considered. Thus, arbitrarily, we can consider that the term period corresponds to a time interval located between 37(+0) SA and 41(+6) SA and the post-term period begins from 42(+0) SA. Because maternal and fetal risks increase at the end of the pregnancy, one can speak, arbitrarily, of prolonged pregnancy from 41(+0) SA (expert opinion).

[Management of post-term neonates]. / Prise en charge pédiatrique du nouveau-né post-terme.

OBJECTIVE: To estimate the modalities of management of post-term neonates. METHODS: This study is based on PubMed search, Cochrane library and HAS recommendations. RESULTS: Medical team should be able to provide neonatal resuscitation in delivery room in case of meconium-stained fluid or perinatal asphyxia according to the international guidelines ILCOR 2010. The glycaemia of the post-term newborn with macrosomia should be evaluated. The initial clinical examination should search complications such as shoulder dystocia or clavicular fracture. Full blood count should be performed in symptomatic newborn post-term. Developmental assessment should be performed in post-term newborn in case of associated pathology. CONCLUSIONS: The risk of perinatal complications is increased in newborn post-term in delivery room and during hospitalization. Medical team should be able to manage these complications.

Power spectrum analysis of fetal heart rate variability at near term and post term gestation during active sleep and quiet sleep.

BACKGROUND: Spectral analysis of fetal heart rate variability is promising for assessing fetal condition. Before using spectral analysis for fetal monitoring it has to be determined whether there should be a correction for gestational age or behavioural state. AIMS: Compare spectral values of heart rate variability between near term and post term fetuses during active and quiet sleep. STUDY DESIGN: Case-control. Cases had a gestational age of > or =42 weeks; controls were 36 to 37 weeks. Fetuses were matched for birth weight percentile. SUBJECTS: STAN registrations from healthy fetuses. For each fetus one 5-minute segment was selected during active and one during quiet sleep. OUTCOME MEASURES: Absolute and normalized low (0.04-0.15 Hz) and high frequency power (0.4-1.5 Hz) of heart rate variability. RESULTS: Twenty fetuses were included. No significant differences were found between cases and controls in absolute (481 and 429 respectively, P=0.88) or normalized low (0.78 and 0.80 respectively, P=0.50) or absolute (41 and 21 respectively, P=0.23) or normalized high frequency power (0.08 and 0.07 respectively, P=0.20) during active state. During rest, normalized low frequency power was lower (0.58 and 0.69 respectively, P=0.03) and absolute (16 and 10 respectively, P=0.04) and normalized high frequency power were higher (0.21 and 0.14 respectively, P=0.01) in cases compared to controls. Absolute and normalized low frequency power were higher during active state compared to rest in both groups (all P values <0.05). CONCLUSIONS: We found sympathetic predominance during active state in fetuses around term. Post term parasympathetic modulation during rest was increased compared to near term.

Determinants of bone mass and size in 7-year-old former term, late-preterm, and preterm boys.

UNLABELLED: When compared, full-term prepubertal boys had greater regional bone size, higher total body (TB) bone mineral content (BMC), and regional bone density than preterm boys but higher TB bone content area and regional BMC than late-preterm boys. Implications include follow-up bone assessment and preterm formula feeding in late-preterm boys. INTRODUCTION: This study was conducted to determine whether there are differences in bone mass and size among prepubertal boys born preterm (PT; < or =34 weeks gestation), late-preterm (LP; >34 and < or =37 weeks gestation), and at term (>37 weeks gestation) and to identify factors that are associated with bone mass and size in these children. METHODS: Total body (TB), spine and hip dual energy X-ray absorptiometry and tibia peripheral quantitative computed tomography measures were obtained on 24 boys aged 5.7 to 8.3 years. RESULTS: In multiple regression analysis adjusting for current weight, height, age, and jump power, term boys had greater cortical thickness (p = 0.03) and area (p = 0.01), higher trabecular volumetric bone mineral density (p = 0.05), TB bone mineral content (BMC; p = 0.007), and hip areal bone mineral density (aBMD; p = 0.01) than PT boys, and higher TB BMC (p = 0.01), TB bone area (p = 0.03), hip BMC (p = 0.02) and aBMD (p = 0.01), and femoral neck BMC (p = 0.05) and aBMD (p = 0.02) than LP boys. There were no differences in activity measures among gestation groups and no group-by-activity interactions. CONCLUSION: Term boys have greater bone size and mass than PT boys and higher bone mass than LP boys at several bone sites. Activity measures did not differ among gestation groups and did not explain bone differences.

Nonlinear dynamical analysis of the neonatal EEG time series: the relationship between sleep state and complexity.

OBJECTIVE: The complexity of the EEG time series during stages of neonatal sleep states is investigated. The relationship between these sleep states, birth status (i.e. preterm and full-term), and the complexity of the EEG is assessed. METHODS: Dimensional complexity, an estimate of the correlation dimension (D(2)) of the EEG time series, is used as a novel index for quantifying the complexity of the EEG time series during different neonatal sleep states. The dimensional complexity is estimated by using both the Grassberger-Procaccia algorithm and Theiler's modified algorithm. Also, the hypothesis that the neonatal EEG time series contains nonlinear features is investigated and verified in certain sleep states using surrogate data testing. RESULTS: Dimensional complexity of the neonatal EEG time series during active (REM) sleep tends to be higher than during quiet (NREM) sleep; while dimensional complexity of the neonatal EEG time series during indeterminate sleep is virtually at the midpoint of the dimensional complexity range between the active and quiet sleep states. Consequently, there are statistically significant differences between the neonatal EEG time series during different sleep states as measured by dimensional complexity. Also, the birth status (preterm or full-term) of the neonate has an influence on dimensional complexity of the neonatal EEG time series. Further, the surrogate data testing null hypothesis for dimensional complexity cannot be rejected during active sleep. CONCLUSIONS: The neonatal EEG time series tends to have statistically different complexities corresponding to different sleep states. Given that the neonatal EEG time series during active sleep is more complex than during quiet sleep, one can suggest that there is greater activity among cortical circuit elements during active as compared to quiet sleep. Further, active sleep neuronal dynamics are best modeled by a linear stochastic process, while in quiet sleep a nonlinear deterministic model may be more appropriate. SIGNIFICANCE: There has been considerable controversy associated with measures of complexity, such as dimensional analysis, as applied to neonatal EEG data. This paper confirms that there are statistically significant differences in dimensional complexity associated with different states of sleep and that the origin of this complexity shifts from linear stochastic to nonlinear deterministic with transitions from active to quiet sleep, and is further influenced by maturation. This may provide important insight into the organization and structure of neuronal networks during sleep and with brain maturation in the neonatal period.

Two cases of postmaturity-related perinatal mortality in non-local expectant mothers.

We present two cases of postmaturity-related perinatal mortality with delivery at 42 weeks 6 days' and 44 weeks' gestation, respectively. No cause beyond postmaturity was found. Neither induction of labour nor foetal monitoring had been performed despite these gestations going post 41 weeks because of a current 'social obstetrics' phenomenon--non-local expectant mothers coming to Hong Kong from mainland China for delivery.

The computerized fetal heart rate analysis in post-term pregnancy identifies patients at risk for fetal distress in labour.

OBJECTIVE: To ascertain the diagnostic ability of a computerized fetal heart rate (FHR) analysis system in the identification of patients at risk of fetal distress in labour. STUDY DESIGN: Three hundred and two healthy post-term pregnancies were enrolled in a retrospective, cross-sectional study and subdivided into two groups, with (n=42) or without (n=260) fetal distress in labour. The last computerized FHR recording before onset of labour was analyzed. RESULTS: The two groups showed a significant difference only in FHR baseline and in percentage of small accelerations on total. The multivariate analysis showed that only the percentage of small accelerations was significantly related to the labour outcome. A higher diagnostic accuracy was obtained with use of neural network analysis, which allowed a sensitivity of 56%, specificity 91%, positive predictive value 53% and negative predictive value 92% with an overall accuracy of 86%. CONCLUSIONS: The increase in FHR baseline and in small FHR accelerations can be major factors in the prediction of subsequent fetal distress in healthy term fetuses. Use of neural networks seems to further improve the ability of computerized FHR analysis in the prediction of intrapartum distress.

Computerised evaluation of fetal heart rate in post-term fetuses: long term variation.

Computerised fetal heart rate records were obtained between 1987 and 1993 using the Sonicaid System 8000 for a cross-sectional study of postdates fetal heart rate variation; 567 singleton pregnancies at 41 and 43 weeks provided 1502 records. In all cases gestational age had been verified by ultrasound examination in early pregnancy. The mean minute range of the long term pulse interval variation, which is known to be correlated with fetal oxygenation was found to decrease progressively from an average value of 48.5 ms at 41 weeks to 46.4 ms and 42.4 ms at 42 and 43 or more weeks, respectively. When conservative management of postdate pregnancies is chosen, accurate measurements are needed to follow the evolution of fetal condition. Reference values for calculated pulse interval variation at later gestational ages are now provided.

Factors affecting outcome in post-term birth.

Studies published in the past year confirm that, under current conditions of good ascertainment of gestational age and careful clinical management of post-term pregnancies, post-term births are not at increased risk of perinatal mortality. They are, however, still at increased risk of intrapartum fetal distress and cesarean birth. The main risk factor for poor fetal and neonatal outcomes is small fetal size. Risk markers for those at risk of intrapartum difficulties include amniotic fluid volume and fetal biophysical profile. While there is no longer increased mortality associated with post-term birth per se, this is very much the result of clinical selection factors and modern perinatal management. Post-term pregnancies remain an obstetrical risk group.

Scalp heat flux in postmature and in growth-retarded fetuses.

Postterm and growth-retarded fetuses share a common problem which can be characterized by a discrepancy between the supply of oxygen and nutrients to, and the demand of the fetus. But, this "insufficient" placental exchange function may also extend to and affect its thermal homeostasis; e.g. when the capacity of convective (placenta) pathways is shifted towards conductive (surface) pathways for heat loss. Therefore, fetal scalp heat flux measurements, where heat serves as an intrinsic tracer for metabolic activity and placental exchange function, promised a new kind of information. In 81 pregnant women during labor we measured fetal scalp heat flux by means of an heat flux transducer attached to the fetal head and after the cervix had dilated to 3 cm. In the healthy fetuses we found a positive linear relationship between scalp heat flux and different anthropometric variables such as body length (r = 0.432, n = 65, P less than 0.01), head circumference and gestational age. In comparison, postmature and growth-retarded fetuses showed higher heat flux values than appropriately grown fetuses of the same length head size and gestational age. Moreover, in those fetuses scalp heat flux decreased by approximately 4 watt/m2 during the second stage and differed in this regard from the control group who showed stable values during labor and delivery. We conclude that scalp heat flux measurements may indicate disturbances of placental exchange before acute hypoxia occurs.

Postterm pregnancy: effects on temperature and glucose regulation.

Pregnancies that extend beyond 42 weeks of gestation have a higher risk for uteroplacental insufficiency than do pregnancies delivered prior to this time. Postterm infants are at risk for meconium aspiration due to uteroplacental insufficiency. Prior research has shown that postterm infants are at risk for temperature- and glucose-regulating difficulties following birth. In this study, the abilities of 63 postterm infants and 88 term infants to regulate temperature and glucose during the first 24 hours of infant age were compared. No significant differences were found in the two groups on the two variables.

Physiologic jaundice in the Nigerian neonate.

In the course of a systemic study of physiologic hyperbilirubinaemia, 200 Nigerian newborn infants were evaluated daily over a 12-day period. The pre-term and post-term neonates exhibited a distinct biphasic pattern of hyperbilirubinaemia. Mean peak bilirubin levels of 8.20 mg/dl for the pre-term, 7.15 mg/dl for the post-term and 8.34 for the term were attained on the fourth, third and fifth days, respectively. Term small for gestational age neonates experienced mean peak bilirubin levels of 7.02 mg/dl at the age of 4 days and maintained a sustained elevation for as long as the last day of the study. Higher values of physiologic hyperbilirubinaemia are observed in this study than has been reported for American neonates.

Fetal umbilical artery flow velocimetry in postdate pregnancies.

This study prospectively examined the use of umbilical artery flow velocimetry for monitoring fetal health in postdate pregnancies. Forty-six patients with well-established dates were evaluated with semiweekly biophysical profiles and umbilical artery flow velocimetry (characterized by the ratio of the peak systolic to end-diastolic velocity). Their labor records were reviewed, and neonates were examined for signs of postmaturity. Twenty neonates had an abnormal test result or outcome (identified as an abnormal nonstress test, oligohydramnios, meconium, intrapartum fetal distress, or a 5-minute Apgar score less than 7). Nine neonates had a physical examination consistent with the postmaturity syndrome. Twenty-one neonates were entirely normal. Comparisons of the mean systolic/diastolic ratios for neonates with and without the complications associated with postdatism showed no significant differences. In addition, all systolic/diastolic ratios were within the normal range. Therefore, umbilical artery flow velocimetry is unlikely to be useful for the routine antenatal assessment of the postdate fetus.

Sonographic biophysical profile in the postdate pregnancy.

One hundred thirty-one postdate pregnancies were evaluated by the sonographic biophysical profile. Results of prenatal testing were compared to neonatal condition. Predictive values were calculated in order to determine whether this testing scheme could be used to detect the fetus at risk for neonatal distress. The results of this study show that a normal biophysical profile score is highly predictive of normal outcome, but an abnormal test has only a 14% predictive value of poor neonatal outcome.