Has the outcome for extremely low gestational age (ELGA) infants improved following recent advances in neonatal intensive care?

Increased Risk for Respiratory Complications in Male Extremely Preterm Infants: A Propensity Score Matching Study

BACKGROUND

Many factors can affect the clinical outcome of extremely premature infants (EPIs), but the effect of sex is paradoxical. This study used propensity score matching to adjust baseline information to reassess the clinical outcome of EPIs based on sex.

METHODS

A retrospective analysis was performed on EPIs admitted in the Department of Neonatology of the Third Affiliated Hospital of Guangzhou Medical University from 2011 to 2020. A propensity score matching (PSM) analysis was used to adjust the confounding factors including gestational age, birth weight, 1-minute Apgar score ≤ 3, withholding or withdrawing life-sustaining treatment(WWLST), mechanical ventilation, duration of mechanical ventilation, the mother with advanced age (≥35 years old), complete-course antenatal steroid therapy and hypertensive disorders of pregnancy. The survival rate at discharge and the incidence of major complications were evaluated between the male and female groups.

RESULTS

A total of 439 EPIs were included, and 240 (54.7%) infants were males. After matching the nine confounding factors, 148 pairs of infants were finally enrolled. There was no significant difference in the survival rate at discharge, as well as the mortality of activating treatment or WWLST between the two groups (all P>0.05). However, the incidence of respiratory distress syndrome, bronchopulmonary dysplasia (BPD), and moderate to severe BPD in the male group was significantly increased (all P<0.01), especially at birth weight between 750 and 999 grams.

CONCLUSIONS

The male EPIs have a higher risk of respiratory complications than females, particularly at 750 to 999 grams of birth weight.

Gestational age-specific sex difference in mortality and morbidities of preterm infants: A nationwide study

This study aims to determine whether male sex has adverse effect on mortality and morbidities in very low birth weight infants (VLBWI) <30 weeks of gestation and to ascertain this sex effect, stratified by gestational age, adjusting for perinatal risk factors. This is a population-based study from Korean Neonatal Network for VLBWI born at 23+0 and 29+6 weeks of gestation between January 2013 and December 2014. The primary outcome was gestation-specific sex difference in the occurrence of mortality, combined morbidities, and individual morbidity. A total of 2228 VLBWI were enrolled (males, 51.7%). Mortality was not different between sexes. The risk of bronchopulmonary dysplasia and combined morbidities was significantly higher in males ≤25 weeks of gestation (odds ratio [OR] 2.08, 95% confidence interval [CI] 1.35-3.20 and OR 2.00, CI 1.19-3.39, respectively). Males had a significantly higher incidence of periventricular leukomalacia at 23 and 29 weeks of gestation. The risk of severe retinopathy of prematurity was higher in females >25 weeks of gestation. Although both sexes have similar risk for mortality, male sex remains an independent risk for major morbidities, especially at ≤25 weeks of gestation. The risk of each outcome for males has a specific pattern with increasing gestational age.

The prediction of later neurodevelopmental status of preterm infants at ages 7 to 10 years using the Bayley Infant Neurodevelopmental Screener

The aim of this study was to see whether the scores of the Bayley Infant Neurodevelopmental Screener of 45 high-risk preterm infants (gestational age 26-37 wk) between the ages of 3 and 24 months predicted neurodevelopmental status at 7 to 10 years of age. Neurodevelopmental status of 45/122 preterm infants, grouped according to their gestational ages of 26 to 29, 30 to 32, and 33 to 37 weeks, were previously evaluated by Bayley Infant Neurodevelopmental Screener. The scores were categorized as low or high-moderate. Verbal and performance scores of Wechsler Intelligence Scale for Children-Revised (WISC-R) of those patients were assessed between 7 and 10 years. The patients with high-moderate-risk scores of Bayley Infant Neurodevelopmental Screener at all times, regardless of their gestational age, had lower performance, verbal, and total scores of WISC-R than those of who had low Bayley Infant Neurodevelopmental Screener risk scores. High-moderate risk score of Bayley Infant Neurodevelopmental Screener at 7 to 10, and 16 to 20 months, of all patients especially showed good prediction for identifying lower verbal and performance scales. For 7 to 10 months, verbal scale: positive predictive value = 92.3%, negative predictive value = 44.4%, sensitivity = 70.58%, and specificity = 80%; performance scale: positive predictive value = 100%, negative predictive value = 30%, sensitivity = 68.18%, and specificity = 100%. For 16 to 20 months, verbal scale: positive predictive value = 90%, negative predictive value = 37.5%, sensitivity = 64.3%, and specificity = 80%; performance scale: positive predictive value = 90%, negative predictive value = 12.5%, sensitivity = 56.3%, and specificity = 50%. Bayley Infant Neurodevelopmental Screener shows good prediction of later verbal and performance scores of Wechsler Intelligence Scale-Revised for Children as early as 7 to 10 months, which gives us the opportunity to start early intervention.

"Early" versus "late" 23-week infant outcomes

OBJECTIVE

To determine whether survival is different in "early" (23(0/7)-23(3/7) weeks) vs "late" (23(4/7)-23(6/7) weeks) infants.

STUDY DESIGN

Records of 126 consecutive liveborn infants delivered at 23(0/7) to 23(6/7) weeks' gestation from 2001-2010 were examined using the Vermont Oxford Network database. Infants born at 23 0/7 to 23 3/7 weeks were grouped into "early" and those at 23 4/7 to 23 6/7 weeks were "late." Clinical characteristics were compared between groups and multivariate analyses were used to predict survival.

RESULTS

Seventy-two infants were early and 54 were late. Survival was 25% vs 56%, respectively (P < .001). The early group was less likely to receive steroids (43% vs 65%; P = .016) and had a lower mean birthweight (547 g vs 596 g; P < .001). No difference in other factors was seen between groups. No change in survival was observed during the study period in either group.

CONCLUSION

Late 23-week infants have improved survival compared with early infants. Delaying delivery as little as 24-96 hours may improve survival for 23-week infants.

Evaluating 2 Year Outcome in Twins ≤ 30 Weeks Gestation at Birth: A Regional Perinatal Unit's Experience

With improved technology in assisted reproductive medicine, there has been an absolute increase in the numbers of twin pregnancies with an associated increase in perinatal mortality and morbidity. This increase in perinatal mortality and morbidity is largely due to a higher incidence of delivering preterm as compared to singletons. Twin pregnancies have their unique complications that include abnormal placental communication and discordant growth which are associated with perinatal mortality and morbidity. The objectives of this study were two-fold: i) to determine if the morbidity/mortality outcome at 18–24 months corrected age seen in a cohort of twins born between 24–30 weeks gestation was significantly different as compared to singleton preterm infants of the same gestation; and ii) to determine and evaluate any differences between monochorionic (MC) and dichorionic (DC) twins. Twins 24–30 weeks gestation at birth born between 01/01/97–30/06/99 were identified and prospectively followed to 18–24 months corrected age (c.a.). They were matched with a singleton infant of the same gender and within 1 week of the same gestation. Obstetrical, neonatal and neurodevelopmental data were gathered and analyzed. The primary outcome was death or the presence of a severe neurodevelopmental deficit at 18–24 months corrected age. Of the 56 sets of twins identified, 52 sets were followed prospectively with 101 infants available for matching. In this cohort, twin pregnancies had a lower incidence of pregnancy-induced hypertension and premature rupture of membranes than singletons (p < 0.05). The two groups were comparable in neonatal characteristics. The incidence of death or severe disability was 29.7% in twins vs. 22.8% in singletons (p = 0.337, Fisher's exact test). The major area of deficit was in the cognitive category for both groups, 9.9% vs. 7.9% respectively. MC twins made up 35.6%; DC twins 64.4%. Twin to twin transfusion syndrome (TTTS) occurred in 6.9%. Discordant growth occurred more frequently in MC pregnancies (p = 0.016). MC twins tended to be more premature, lower in birth weight, and experience neonatal morbidity in the form of patent ductus arteriosus and sepsis (p < 0.05) as compared to DC twins. However, the primary outcome of death or severe neurodevelopmental deficit at 18–24 months c.a. was not significantly different between the two groups, 38.9% (MC) vs. 24.6% (DC), (p = 0.173, Fisher's exact test). Neurodevelopmental morbidity or mortality in twins with TTTS was 42%. Mortality and severe neurodevelopmental morbidity were not significantly higher in twins as compared to singletons in this cohort. However, the trend is slightly higher in twins, which may have clinical significance. Though not statistically significant, the incidence of 38.9% in adverse outcome with MC twins may be clinically significant. With the number of twins steadily increasing, further monitoring is required to determine future directions in intervention and research. Early recognition of monochorionicity remains essential to optimize care and neurodevelopment for these infants.

Infant neurobehavioral development

The trend toward single-room neonatal intensive care units (NICUs) is increasing; however scientific evidence is, at this point, mostly anecdotal. This is a critical time to assess the impact of the single-room NICU on improving medical and neurobehavioral outcomes of the preterm infant. We have developed a theoretical model that may be useful in studying how the change from an open-bay NICU to a single-room NICU could affect infant medical and neurobehavioral outcome. The model identifies mediating factors that are likely to accompany the change to a single-room NICU. These mediating factors include family centered care, developmental care, parenting and family factors, staff behavior and attitudes, and medical practices. Medical outcomes that plan to be measured are sepsis, length of stay, gestational age at discharge, weight gain, illness severity, gestational age at enteral feeding, and necrotizing enterocolitis (NEC). Neurobehavioral outcomes include the NICU Network Neurobehavioral Scale (NNNS) scores, sleep state organization and sleep physiology, infant mother feeding interaction scores, and pain scores. Preliminary findings on the sample of 150 patients in the open-bay NICU showed a "baseline" of effects of family centered care, developmental care, parent satisfaction, maternal depression, and parenting stress on the neurobehavioral outcomes of the newborn. The single-room NICU has the potential to improve the neurobehavioral status of the infant at discharge. Neurobehavioral assessment can assist with early detection and therefore preventative intervention to maximize developmental outcome. We also present an epigenetic model of the potential effects of maternal care on improving infant neurobehavioral status.

Perinatal and neonatal mortality in Northwest Greece (1996-2004)

OBJECTIVE

An improvement in perinatal mortality is reported in various countries. This is a retrospective analysis of perinatal and neonatal mortality in Northwest (NW) Greece.

METHODS

Analysis was made of the births and deaths register in NW Greece and records of the regional referral tertiary care center and the National Hospitals at the same area for the period 1996-2004. Perinatal mortality was analysed according to birthweight (BW) and gestational age (GA) for two separate periods, 1996-1999 (I) and 2000-2004 (II), corresponding to an increase in antenatal steroid use from 20% to 63%.

RESULTS

Neonatal mortality improved between the two periods in infants with very low BW [very low birth weight (VLBW), <1500 g] and the very preterm infants (<28 weeks GA). Severe respiratory distress syndrome (RDS) decreased (p<0.001) for infants with GA≤34 weeks and those with BW 751-1500 g (p<0.02), and perinatal asphyxia is no longer a leading cause of death. Intrauterine transfer increased (p<0.001) for infants with BW≤1500 g. The main cause of death as derived from birth records and neonatal intensive care unit records is prematurity, alone or with complications.

CONCLUSIONS

With the introduction of antenatal steroids and increase in intrauterine transfer there has been a decrease in neonatal mortality of VLBW infants in NW Greece.

Survival and major disability rate in infant born at 22-25 weeks of gestation

Our aim was to evaluate the literature on survival and major disability rate in preterm infants born at 22- 25 weeks of gestational age (GA). Thirty-three studies were identified and reviewed. Survival was lower in population-based studies (2% at 22, 13% at 23, 35% at 24, and 56% at 25 weeks) than in center-based study (15% at 22, 41% at 23, 58% at 24, and 74% at 25 weeks). The severe disability rate was slightly higher in population-based studies than in center-based studies at 23 (29 vs. 32%) and at 24 (30 vs. 27%) week of GA, whereas it was similar in population and center-based studies at 25 (21 vs. 22%) weeks of GA. Survival rate seems to improve with time, whereas the change of severe disability rate cannot be adequately evaluated due to the paucity of available data. We conclude that the survival of infants born at 22 weeks is still an uncommon event, whereas the survival of infants born at 23, and mostly at 24 and 25 weeks of GA is significant in the majority of studies.

Behaviour and quality of life at school age of children who had bronchopulmonary dysplasia

BACKGROUND

There is little information available concerning behavioural and functional health problems in children who had bronchopulmonary dysplasia (BPD).

AIM

To compare behavioural problems and quality of life in a cohort of children at school age who had BPD with preterm and term controls.

METHODS

The cohort of 78 BPD children of 26 to 33 weeks' gestation was matched for birth weight with preterm controls. At school age follow-up, information was available for 66 BPD children and 60 preterm controls. (Three children with severe cerebral palsy were excluded). Parents completed the Child Behaviour Checklist (CBCL) and the Child Health Questionnaire (CHQ). The child's teacher completed the Teacher Report Form (TRF) of the CBCL, with the teachers of the BPD children completing a TRF on a classroom control. Parents completed a questionnaire on their levels of anxiety and depression.

RESULTS

The mean total problem score on the CBCL for the BPD children was similar to the controls, with the BPD children displaying more internalising behaviours. Little variation was seen between the BPD and preterm children on the TRF. Significant differences between classroom controls and the BPD children were found for the total problem scores (p=0.001), internalising behaviours (p=0.01) and social (p=0.047), attention (p=0.0001) and thought problems (0.047). Results from the CHQ showed no difference between the groups in their physical health or the impact of health problems on family life.

CONCLUSION

BPD children at school age display more internalising behaviour than preterm controls, with marked differences on comparison with classroom controls. Quality of life, however, does not seem to be adversely affected compared to the preterm controls.

Lower mortality but higher neonatal morbidity over a decade in very preterm infants

Better perinatal care has led to better survival of very preterm children, but may or may not have increased the number of children with cerebral and pulmonary morbidity. We therefore investigated the relationship between changes in perinatal care during one decade, and short-term outcome in very preterm infants. Perinatal risk factors and their effects on 28-day and in-hospital mortality, and on intraventricular haemorrhage and bronchopulmonary dysplasia (BPD) in survivors, were compared in two surveys of very preterm singleton infants in the Netherlands. Between 1983 and 1993, 28-day mortality decreased from 52.1% to 31.8% in infants of 25-27 weeks' gestation and from 15.2% to 11.3% in infants of 28-31 weeks' gestation. The incidence of intraventricular haemorrhage in survivors did not change (44.4% and 43.3% in infants of 25-27 weeks' gestation, and 29.0% and 24.0% in infants of 28-31 weeks' gestation). The incidence of BPD in survivors increased from 40.3% to 60.0% in infants of 25-27 weeks' gestation and remained similar in infants of 28-31 weeks' gestation (8.5% and 9.8% respectively). In multivariable analysis, higher mortality was associated with congenital malformation, low gestational age, low birthweight, no administration of steroids before birth, low Apgar scores and intraventricular haemorrhage, in 1983 as well in 1993, and with male gender in 1993. The effect of maternal age on mortality diminished significantly between 1983 and 1993. Intraventricular haemorrhage in surviving children was associated with low gestational age and artificial ventilation, both in 1983 and in 1993. The effect of artificial ventilation on the incidence of intraventricular haemorrhage diminished significantly between 1983 and 1993. BPD was associated with low gestational age and artificial ventilation, both in 1983 and in 1993, and with low birthweight and caesarean section in 1993. We conclude that the better survival of very preterm infants, especially of those of 25-27 weeks' gestation, has been accompanied by a similar incidence (and thus with an increased absolute number) of children with intraventricular haemorrhage and by an increased incidence of children with BPD.

Outcome of perinatal care for very preterm infants at 5 years of age: a comparison between 1983 and 1993

Perinatal mortality in very preterm infants has decreased by up to 50% during the last decades. Studies of changes of long-term outcome are inconclusive. We studied the visual, auditory, neuromotor, cognitive and behavioural development of two geographically defined populations of very preterm, singleton infants, born in 1983 and in 1993, and analysed the relationship between perinatal risk factors and outcomes. The incidence of disabling cerebral palsy increased from 6.0% to 11.1% (OR 2.45 [95% CI 1.11, 5.38]). Impaired vision and strabismus decreased significantly, presumably by continuous monitoring of pO(2). Hearing problems, the need for special education and the incidence of behavioural problems did not change over time. The proportion of children who showed optimal performance in every developmental domain increased from 29.5% in 1983 to 43.2% in 1993. Cerebral palsy was associated with male gender in 1983, with low Apgar score and intraventricular haemorrhage in 1993, and with seizures both in 1983 and in 1993. The intensiveness of neonatal treatment has increased, leading to the survival of many more healthy infants, but at the cost of more infants with cerebral damage. Modern perinatal care is no longer limited by the devastating effects of pulmonary problems as it was in the past, but fails to safeguard cerebral integrity in very preterm infants.

Quality-of-care indicators for the neurodevelopmental follow-up of very low birth weight children: results of an expert panel process

OBJECTIVE

To develop a set of quality indicators for the neurodevelopmental follow-up care of very low birth weight (VLBW; <1500 g) children.

METHODS

We reviewed the scientific literature on predictors of neurodevelopmental outcomes for VLBW children and the clinical practice guidelines relevant to their care after hospital discharge. An expert panel with members nominated by the American Academy of Pediatrics, the National Institute of Child Health and Human Development, the Vermont Oxford Network, and the California Children's Service was convened. We used a modified Delphi method to evaluate and select the quality-of-care indicators.

RESULTS

The panel recommended a total of 70 indicators in 5 postdischarge follow-up areas: general care; physical health; vision, hearing, speech, and language; developmental and behavioral assessment; and psychosocial issues. Of these, 58 (83%) indicators were in preventive care, 5 (7%) were in acute care, and 7 (10%) were in chronic care.

CONCLUSION

The quality indicators cover follow-up care for VLBW infants with various medical conditions. Given the elevated rates of long-term neurodevelopmental disabilities and the potential impact of poor health care, this new set of indicators provides an opportunity to assess and monitor the quality of follow-up care with the ultimate aim of improving the quality of care for this high-risk population.

Actuarial survival of a large Canadian cohort of preterm infants

Background

The increased survival of preterm and very low birth weight infants in recent years has been well documented but continued surveillance is required in order to monitor the effects of new therapeutic interventions. Gestation and birth weight specific survival rates most accurately reflect the outcome of perinatal care. Our aims were to determine survival to discharge for a large Canadian cohort of preterm infants admitted to the neonatal intensive care unit (NICU), and to examine the effect of gender on survival and the effect of increasing postnatal age on predicted survival.

Methods

Outcomes for all 19,507 infants admitted to 17 NICUs throughout Canada between January 1996 and October 1997 were collected prospectively. Babies with congenital anomalies were excluded from the study population. Gestation and birth weight specific survival for all infants with birth weight <1,500 g (n = 3419) or gestation ≤30 weeks (n = 3119) were recorded. Actuarial survival curves were constructed to show changes in expected survival with increasing postnatal age.

Results

Survival to discharge at 24 weeks gestation was 54%, compared to 82% at 26 weeks and 95% at 30 weeks. In infants with birth weights 600–699, survival to discharge was 62%, compared to 79% at 700–799 g and 96% at 1,000–1,099 g. In infants born at 24 weeks gestational age, survival was higher in females but there were no significant gender differences above 24 weeks gestation. Actuarial analysis showed that risk of death was highest in the first 5 days. For infants born at 24 weeks gestation, estimated survival probability to 48 hours, 7 days and 4 weeks were 88 (CI 84,92)%, 70 (CI 64, 76)% and 60 (CI 53,66)% respectively. For smaller birth weights, female survival probabilities were higher than males for the first 40 days of life.

Conclusion

Actuarial analysis provides useful information when counseling parents and highlights the importance of frequently revising the prediction for long term survival particularly after the first few days of life.

Willingness or unwillingness to perform cesarean section for impending preterm delivery at 24 weeks' gestation: a cost-effectiveness analysis

OBJECTIVE

This study was undertaken to compare the costs and health outcomes of 2 management options when encountering a 24-week gestation in labor.

STUDY DESIGN

We constructed a decision model for willingness versus unwillingness to perform cesarean section for fetal indication (aggressive vs nonaggressive management). We modeled chance nodes for stillbirth, neonatal death, and long-term survival, with and without major morbidity. Main outcome measures were intact (healthy) infant and live infant. Cost-effectiveness analysis was conducted from a societal perspective to determine the cost-effectiveness of the 2 strategies.

RESULTS

The probabilities of both intact survival (16.8% vs 12.9%) and survival with major morbidity (39.2% vs 19.4%) were higher with willingness to perform cesarean section. Nonaggressive management was less costly for delivery at 24 weeks' gestation. Aggressive management strategy would cost dollar 4,680,387 more than nonaggressive management for each additional intact infant, and dollar 766,241 more per additional live infant.

CONCLUSION

Although the probability of survival is increased by physician willingness to perform cesarean section, the more cost-effective strategy is unwillingness because of a strong relationship to the increased probability of survival with major morbidity when physicians are willing to perform cesarean section for fetal indications.

Ensuring accurate knowledge of prematurity outcomes for prenatal counseling

OBJECTIVES

To determine the accuracy of knowledge of different health care providers regarding survival and long-term morbidity rates for very premature infants and to examine whether a focused educational intervention improves the accuracy of this knowledge and influences health care decisions.

METHODS

Using hypothetical case scenarios with infants at < or =28 weeks of gestation, we surveyed a variety of caregivers involved in perinatal communication and decision-making processes at a tertiary center that provides intensive care for neonates. We asked physicians from the pediatrics and obstetrics services and nurses and nurse practitioners from the NICU and obstetrics ward for their best estimates of survival and major long-term disability rates and for their opinions regarding the appropriateness of resuscitation and life support at each week of gestation of <29 weeks. After the survey, we educated all providers about current data on survival and long-term disability rates for preterm infants and gave them pocket-sized cards summarizing this information for reference during prenatal counseling. One month after the educational intervention and complete dissemination of the cards, a questionnaire with questions identical to those in the first survey was mailed to the same individuals.

RESULTS

Fifty-one health care providers were involved in the baseline survey. The response rates for the postintervention survey were 100% for physicians (20 of 20 subjects) and nurses (20 of 20 subjects) and 91% (10 of 11 subjects) for the nurse practitioners. In the baseline survey, statistically significant underestimates of survival rates were seen for physicians and nurses at 23 to 28 weeks of gestation and for nurse practitioners at 23 to 27 weeks of gestation. Statistically significant overestimates of disability rates were seen for physicians and nurse practitioners at < or =26 weeks of gestation and for nurses at < or =28 weeks of gestation. After the intervention, respondents demonstrated significant improvements in the accuracy of survival and disability estimates at many, but not all, gestational ages. Although underestimation of survival rates and overestimation of disability rates decreased after the intervention, it persisted to some degree. After the intervention, a larger proportion of physicians (53% vs 21%) and a smaller proportion of nurses (10% vs 37%) were likely to recommend resuscitation for infants born at 23 weeks of gestation.

CONCLUSIONS

Physicians, nurses, and nurse practitioners underestimated survival rates and overestimated long-term disability rates for very premature infants. After education, their estimates of survival and long-term disability rates for these infants improved significantly. More accurate estimates of survival and disability rates affected physicians' and nurses' theoretical decision-making regarding the appropriateness of resuscitation at 23 weeks of gestation.

Ethical dilemmas in the care of the most premature infants: the waters are murkier than ever

PURPOSE OF REVIEW

Summarize the literature relevant to ethical issues surrounding decisions to provide intensive care to extremely premature newborns.

RECENT FINDINGS

A Texas Supreme Court decision and a position paper are noteworthy for health professionals participating in management decisions with families at risk for extremely preterm delivery.

SUMMARY

In Miller v HCA, the Millers sued the Hospital Corporation of America for resuscitating their approximately 23-week gestation daughter against their wishes. The baby survived with severe neurodevelopmental disabilities. They were awarded $59.9 million in a jury trial. However, the judgment was reversed by the court of appeals, which ruled that parents have no right to withhold urgently needed life-sustaining medical treatment from children with non-terminal impairments, deformities, or disabilities, regardless of their severity. The Supreme Court of Texas upheld that ruling, but reasoned that parents have no right to refuse resuscitation of extremely premature infants prior to birth because they cannot be fully evaluated until birth; therefore, decisions before birth could not be fully informed. Robertson (Hasting Center Report 2004) supports precluding parental refusal of resuscitation before birth. He argues that parents have a right to withhold or withdraw medical treatment from a non-terminally ill child, but only if the child will lack capacity for symbolic interaction. Such severe limitation of quality of life concerns in decision making for extremely premature newborns is inconsistent with current published guidelines, the positions of noted bioethicists, and the practice of many neonatologists. Further, the additional information attained by initiating intensive care in the most premature infants does not justify doing so without parental consent.

Short-term outcome in infants with a birthweight less than 501 grams

AIM

To report survival and morbidity until discharge in preterm infants <501 g with life support started immediately after birth.

METHODS/STUDY DESIGN

Cohort study of all preterm infants with birthweights < 501 g born in three tertiary perinatal centres between 1 January 1998 and 31 December 2001 (gestational age (GA) 25.2 [21.0-30.7] wk; birthweight 435 [290-500] g; median [range]).

RESULTS

A total of 107 infants with birthweights <501 g were born. Twenty-nine were stillborn. A prenatal decision to initiate life support immediately after birth was reached in 9/37 (24%) infants <24.0 wk GA and in 39/42 (93%) infants > or =24.0 wk GA. Survival was 3/37 (8%) and 26/41 (63%) in infants <24 wk GA and > or =24.0 wk GA, respectively. Twenty-nine of the 48 infants with immediate life support (60%) survived (95% CI: 46-75%). Forty-two of these 48 (88%) infants were small for gestational age. No infant without immediate life support survived (0/30). Twenty-three (79%) survivors developed chronic lung disease (CLD) and eight (28%) received photocoagulation for retinopathy of prematurity (ROP).

CONCLUSION

In this population of extremely low birthweight infants, survival was higher than in previous studies when life support was provided immediately after birth. Short-term morbidity was similar to other studies. The presented data on survival support our concept to offer immediate life support after birth in preterm infants with birthweights <501 g. The long-term outcome of these infants needs to be assessed urgently.

Perinatal intervention and neonatal outcomes near the limit of viability

OBJECTIVE

The purpose of this study was to evaluate trends in the level of obstetric and neonatal intervention near the limit of viability and perinatal morbidity and mortality rates over time.

STUDY DESIGN

In this retrospective chart review, live-born infants who were delivered at 23 to 26 weeks of gestation and who weighed between 500 and 1500 g between 1990 and 2001 in an urban tertiary care center were identified. Maternal charts were reviewed for clinical characteristics and antenatal and intrapartum course. Neonatal charts were reviewed for short-term morbidities that included respiratory distress syndrome, intraventricular hemorrhage, necrotizing enterocolitis, retinopathy of prematurity, and survival. The study group was divided into 2 cohorts (group I:1990-95; group II:1996-2001); the obstetrician's willingness to intervene, neonatal resuscitation efforts, infant mortality (in gestational age subgroups) rate, and short-term morbidity rate were compared. Multivariate analyses, which controlled for obstetrician willingness to intervene, neonatal resuscitation, cohort, and gestational age, were performed to evaluate infant survival in the entire cohort and for morbidity in the survivors.

RESULTS

Records for 260 mothers and 293 newborn infants were evaluated. Comparing the 2 cohorts (group I vs II), we found increases over time in intent to intervene for fetal indication (70% vs 89%; P = .0007), cesarean delivery for malpresentation (20% vs 42%; P = .0003), and survival (54% vs 70%; P = .003). Pregnancies in group 1 were less likely to have received antenatal steroids (7.7% vs 60%) or surfactant (39% vs 73%; P <.0001 for each). Survival increased with advancing delivery gestation (24%, 51%, 68%, and 85% at 23, 24, 25, and 26 weeks of gestation, respectively; P <.0001). However, among survivors, the incidences of necrotizing enterocolitis, retinopathy of prematurity, intraventricular hemorrhage, respiratory distress syndrome, sepsis, and bronchopulmonary dysplasia did not decline significantly with advancing gestational age, after controlling for other factors.

CONCLUSION

Obstetric intervention and aggressive neonatal resuscitation have increased for pregnancies delivered between 23 and 26 weeks of gestation over the past decade. Although survival has increased over time and with advancing gestational age at delivery, short-term morbidity in survivors is similar, regardless of gestational age in this cohort. A brief delay in delivery of those pregnancies who are at risk for delivery between 23 and 26 weeks of gestation may improve survival, although short-term morbidity in survivors will not be affected substantially.

Fetal infants: the fate of 4172 infants with birth weights of 401 to 500 grams--the Vermont Oxford Network experience (1996-2000)

OBJECTIVE

Improvement in the survival of extremely low birth weight infants requires that we evaluate the limits of our care and assess the impact of treatment on a population of infants who previously rarely survived.

METHODS

A review was conducted of demographic and clinical data of infants who had birth weight 401 to 500 g and were entered in the Vermont Oxford Network Database between 1996 and 2000.

RESULTS

A total of 4172 infants who weighed 401-500 g (mean gestational age: 23.3 +/- 2.1 weeks) were born at 346 participating centers. Overall, 17% survived until discharge. A total of 2186 (52%) died in the delivery room (DR), and 1986 (48%) were admitted to a neonatal intensive care unit (NICU). Compared with infants who died in the DR, infants who survived the DR and were admitted to the NICU were more likely to be female (58% vs 49%), to be small for gestational age (56% vs 11%), to have received prenatal steroids (61% vs 12%), and to have been delivered by cesarean section (55% vs 5%). Thirty-six percent of NICU admissions survived to discharge. Mean gestational age of the 690 NICU survivors was 25.3 +/- 2.0 weeks. These survivors experienced significant morbidity in the NICU.

CONCLUSIONS

An appreciable number of these marginally viable fetal infants survive. They experienced a high rate of serious morbidities while in the NICU. There is very little information about long-term outcomes, as the medical and developmental status of few of these infants has been followed carefully. Parents should be made aware of the high incidence of serious problems, and concerted efforts should be made to follow the status of these infants.

Preschool outcome of less than 801-gram preterm infants compared with full-term siblings

OBJECTIVE

Extremely low birth weight (ELBW) infants are at greater risk for neurodevelopmental delay than full-term infants. Outcomes may be compromised secondary to abnormal brain development associated with complications of prematurity. Long-term cognitive outcome has also been reported to be significantly influenced by postnatal factors. The objective of this study was to clarify the effects of prematurity separate from environmental factors on growth and neurodevelopmental outcomes by comparing ELBW children with their full-term siblings.

METHODS

The study consisted of 25 ELBW children, a subset selected from a larger population of infants who were <801 g birth weight and enrolled in a longitudinal follow-up project from birth and their 25 full-term, full-weight siblings. Twenty-three sets of siblings were evaluated at 5 years of age and 2 sets at 3 years of age with standardized medical, social, cognitive, motor, and language testing. Physical and neurodevelopmental outcomes were compared between groups, controlling for gender and socioeconomic status (SES).

RESULTS

At follow-up, ELBW children were lighter, were shorter, and had smaller head circumference. The ELBW children had lower Stanford-Binet IQs (85 +/- 12 [mean +/- SD] and 95 +/- 11), with lower Stanford-Binet subtests except short-term memory and quantitative reasoning, lower spelling scores on the Wide Range Achievement Test, and lower Peabody motor quotients (79 +/- 11 and 92 +/- 17). Preschool Language Scale quotients were not different, but other receptive language measures were lower for ELBW children. High SES seemed to modify the impact of preterm status on cognitive and language but not motor scores. The mean IQ for high-SES ELBW children was equivalent to that of the low-SES term siblings.

CONCLUSIONS

Preschool-age cognitive and language functioning in ELBW children seemed to be affected by both prenatal and birth influences (preterm status) and postnatal influences (SES variables). Motor scores were significantly related to preterm status but not to SES.

Preterm male infants need more initial respiratory and circulatory support than female infants

AIM

The aim of this study was to investigate possible gender-related differences in clinical parameters during the first week of life that could explain the higher morbidity and mortality of preterm male infants.

METHODS

In total, 130 clinical variables were collected from 236 inborn infants (130 male and 106 female infants) with gestational age (GA) < 29 wk. A subgroup of 175 extremely low birthweight infants (ELBW) < 1000 g (n = 86 males; n = 89 females) was analysed separately.

RESULTS

At 6 postnatal h, 60.8% of the male infants needed mechanical ventilation versus 46.2% of the females (p = 0.026). Chronic lung disease (CLD) developed in 36.2% of males versus 9.8% of female infants (p = 0.004). Inotrope support with dopamine was used in more than 50% of the infants; additional inotrope support to dopamine was needed by 19.4% of male and 9.7% of female infants (p = 0.041). The gender-related difference in need for inotrope support was more evident among the ELBW infants; 67.1% of male infants needed inotrope support versus 50.6% of females (p = 0.028). At 12-24 h, male ELBW infants had lower minimum mean arterial blood pressure (mean (SD) 25(4) mmHg vs 28(6) mmHg, p = 0.004)) and lower minimum PaCO2 than females infants (4.3 (1.1) kPa vs 4.7 (0.9) kPa, p = 0.043).

CONCLUSIONS

There are early gender-related differences in need for ventilatory and circulatory support that may contribute to the worse long-term outcome in prematurely born male infants.

Psychoeducational outcome at school age of preterm infants with bronchopulmonary dysplasia

OBJECTIVE

To investigate the cognitive performance and educational attainment at school-age of children with bronchopulmonary dysplasia (BPD), compared with a preterm control group of children.

METHODS

Seventy preterm infants with BPD and 61 birth weight matched controls were prospectively followed-up to school-age. The Weschler Intelligence Scale for Children - III (WISC), the Wide Range Achievement Test (WRAT) and the Developmental Test of Visual Motor Integration (VMI) were administered. The results were compared between the two groups and multiple regression analyses were performed to determine the effect of confounding variables.

RESULTS

The children in the BPD group performed less well on the Full Scale IQ (mean 86.7 vs 93.5; 95% CI, 1.9-11.7), Verbal IQ (mean 87.1 vs 94.1; 95% CI, 2.0-12.0) and the Performance IQ (mean 88.6 vs 95.2; 95% CI, 2.0-11.2) of the WISC, the reading component of the WRAT (mean 93.8 vs 98.9; 95% CI, 0.3-9.8) and the VMI (mean 88.9 vs 93.3; 95%, CI 1.1-7.8). Despite controlling for social and biological variables, statistical differences persisted for Full Scale and Verbal IQ and reading. A Verbal IQ >1 SD below the mean was found in 41% of BPD children compared to 21% of controls, while on the reading component of the WRAT a greater proportion of BPD children also had scores>1 SD below the mean.

CONCLUSION

Impaired psychoeducational performance was found in preterm children with BPD compared to controls, especially in the areas of language abilities and reading skills. This supports a greater need for special educational services and counseling for parents for these children.

Guidelines for resuscitation in the delivery room of extremely preterm infants

Ethical problems related to intensive care of extremely preterm newborns of < or = 25 weeks' gestational age and at risk of disability have been extensively debated. The Bioethical Committee of the Department of Paediatrics of the University Hospital of Padua organized and started a multidisciplinary group to release guidelines to help staff facing problems related to prematurity. The vitality limit, survival, outcome, and ethical aspects were analyzed. Consequently, we suggest the following: at 22 weeks' gestational age, the deliverance of comfort care only; at 23 weeks, in the presence of detectable vital signs, the practice of immediate intubation, respiratory support, and a reassessment of the neonatal conditions; and at 24 weeks, the provision of intubation, ventilatory support, and cardiovascular resuscitation. If the clinical age and anamnestic gestational age are different, we proceed according to the more advanced one. The importance of providing parents with correct information and the role of comfort care are outlined.

Ethical considerations in the management of infants born at extremely low gestational age

With ongoing improvements in technology and the understanding of neonatal physiology, there has been increasing debate regarding the gestational age and birth weight limits of an infants' capability of sustaining life outside the womb and how this is to be determined. The objective of this review was to address this issue with an analysis of current data (following the introduction of surfactant therapy in 1990) from published studies of survival in extremely low gestational age infants. We found that survival was possible at 22 completed weeks of gestation but only in < 4% of live births reported. Survival increased from 21% at 23 weeks gestational age to 46% at 24 weeks gestational age. Historically, despite continual advances in neonatology, the mortality at 22 weeks has not improved over the past three decades. Combining the data from studies on survival with evidence from developmental biology, we believe that it is not worthwhile to pursue aggressive support of infants born at < 23 weeks gestational age. Given the complicated issues related to morbidity and mortality in infants born at 22 to 25 weeks gestational age and the ethical implications of the available evidence, we propose the need for a consensus derived framework to help in decision-making.

Is retinopathy of prematurity increasing among infants less than 1250 g birth weight?

OBJECTIVE

Retinopathy of prematurity (ROP) is a complication seen in many very low birth weight infants. Severe ROP has been called a "marker" for severe disability. The purpose of this study was to evaluate the occurrence and severity of ROP among infants < or =1250 g birth weight treated in the Special Care Nursery at Women & Infants' Hospital over a period of 7 years from 1994 to 2000.

STUDY DESIGN

This was a retrospective review of ROP data combined with neonatal follow-up data. Of the 1002 infants born with birth weights <1250 g, ophthalmologic data were available for 739 of 839 survivors. Analysis of variance and chi2 along with logistic regression were used to analyze outcomes.

RESULTS

An increase in the overall occurrence of ROP was identified (40% to 54% linear trend, p=0.007). The occurrence of threshold ROP ranged from 2% to 5% (NS). Infants at greatest risk of ROP were those micropremies with birth weights <750 g (p<0.001).

CONCLUSION

Severe ROP continues to be a significant morbidity among infants <750 g.

Management decisions in extremely premature infants

Survival rates in excess of 25% at 23 weeks' gestation and in excess of 50% at 24 weeks' gestation have been reported among live births in the 1990s within tertiary perinatal care centres in the USA and Australia. Decisions about medical management at these gestational ages can no longer be based merely on whether survival is possible. Relevant moral considerations include the primacy of the newborn's best interests, parental autonomy, physicians' duties of beneficence and non-maleficence, and distributive justice. There is significant variability between developed nations in the survival of extremely premature infants among cohorts born within perinatal tertiary care centres. This is, at least to some degree, the result of differences in the aggressiveness of obstetrical and neonatal management at these gestational ages. There is also great variability in the prevalence of major neurodevelopmental disability among survivors. Moreover, the prevalence of major disabilities does not inform quality-of-life considerations adequately. Despite similar gestational age ranges over which the benefit:burden ratio of aggressive obstetric and neonatal care is questioned in developed countries, there is marked variation in the frequency with which it is provided within these ranges. This is understandable given the relevant moral values and the different ways in which competing values will be balanced by different individuals, cultures and societies; the increasing survival of extremely premature infants, but the persistence of high (but widely variable) prevalences of major disabilities reported among survivors and even higher prevalences of mild-to-moderate neurodevelopmental sequelae; our imperfect ability to estimate an individual extremely premature infant's prognosis; and the complexities of estimating the quality of life from the individual's own perspective.

Development and evaluation of a follow up assessment of preterm infants at 5 years of age

BACKGROUND

Long term follow up shows a high frequency of developmental disturbances in preterm survivors of neonatal intensive care formerly considered non-disabled.

AIMS

To develop and validate an assessment tool that can help paediatricians to identify before 6 years of age which survivors have developmental disturbances that may interfere with normal education and normal life.

METHODS

A total of 431 very premature infants, mean gestational age 30.2 weeks, mean birth weight 1276 g, were studied at age 5 years. Children with severe handicaps were excluded. The percentage of children with a correctly identified developmental disturbance in the domains cognition, speech and language development, neuromotor development, and behaviour were determined.

RESULTS

The follow up instrument classified 67% as optimal and 33% as at risk or abnormal. Of the children classified as at risk or abnormal, 60% had not been identified at earlier follow up assessments. The combined set of standardised tests identified a further 30% with mild motor, cognitive, or behavioural disturbances. The paediatrician's assessment had a specificity of 88% (95% CI 83-93%), a sensitivity of 48% (95% CI 42-58%), a positive predictive value of 85% (95% CI 78-91%), and a negative predictive value of 55% (95% CI 49-61%).

CONCLUSIONS

Even after standardised and thorough assessment, paediatricians may overlook impairments for cognitive, motor, and behavioural development. Long term follow up studies that do not include detailed standardised tests for multiple domains, especially fine motor domain, may underestimate developmental problems.

Mortality and neurologic, mental, and psychomotor development at 2 years in infants born less than 27 weeks' gestation: the Leiden follow-up project on prematurity

OBJECTIVE

To determine the outcome of infants with a gestational age (GA) <27 weeks, born in the mid-1990s.

DESIGN

Regional, prospective study; part of the Leiden Follow-Up Project on Prematurity.

SETTING

Three health regions in The Netherlands.

PATIENTS

A total of 266 live born infants (1996/1997) with GA <32 weeks; 46 infants were <27 weeks.

MAIN OUTCOME MEASURES

Neurologic examination (according to Hempel) and assessment of mental and psychomotor development using the Bayley Scales of Infant Development I, at the corrected age of 2 years.

RESULTS

Mortality was 35% (16 of 46) <27 weeks, compared with 6% (14 of 220) in infants with GA 27 to 32 weeks; withdrawal of treatment in 60% and 43%, respectively. Below 27 weeks mortality was higher after extra-uterine transport and pregnancy induction. Neonatal morbidity was higher in infants <27 weeks compared with infants 27 to 32 weeks. Below 27 weeks postnatal use of dexamethasone and being hospitalized at term were associated with abnormal neurologic outcome; there was a higher incidence in (mild) mental developmental delay compared with the older infants. Adverse outcome (dead or abnormal neurologic, psychomotor, or mental development) in infants 23 to 24, 25, 26, and 27 to 32 weeks GA was, respectively, 92% (11 of 12), 64% (7 of 11), 35% (8 of 23), and 18% (40 of 220).

CONCLUSIONS

Mortality and neonatal morbidity were higher in infants with GA <27 weeks compared with infants born between 27 and 32 weeks. The high adverse outcome of infants <25 weeks suggests that one should carefully weigh whether or not to aggressively resuscitate and treat these extremely premature infants.

The impact of surgery on infants born at extremely low birth weight

PURPOSE

The aim of this study was to determine the outcome of extremely low-birth-weight infants (ELBW) requiring surgical interventions for the complications of prematurity

METHODS

One hundred eighty-seven consecutive infants with a birth weight less than 1,000 g treated over a 5-year period were reviewed. Outcome variables included number and types of surgical procedures; length of stay; survival rate and; pulmonary, neurologic, and gastrointestinal morbidity.

RESULTS

Surgical interventions were required in 66 (35%) infants (group S) weighing less than 1,000 g at birth (33% necrotizing enterocolitis/bowel perforation, 36% patent ductus arteriosus, 56% other). Overall mortality rate for group S infants was 23% compared with 22% for those not requiring surgery (group NS; P >.05). Mortality rate rose to 38% for those infants undergoing procedures for necrotizing enterocolitis/bowel perforation (P <.05). Although neurologic and pulmonary morbidity for the entire population were high, there was no difference in their incidence between surgical and nonsurgical groups (29% v 26% and 44% v 65%, group S v group NS, respectively; P >.05).

CONCLUSIONS

These data suggest an improving outcome for ELBW infants. Common associated morbidities of prematurity do not appear adversely affected by surgical interventions supporting an aggressive approach to the care of these infants at the extreme of life.

Neonatal outcome of infants born at 500 to 800 grams from 1990 through 1998 in a tertiary care center

OBJECTIVE

To assess if there have been changes in survival, demographic data, obstetric features, neonatal morbidity, and short-term neurologic/radiographic/neurosensory outcome of 500- to 800-g infants born in a tertiary care neonatal center from 1990 through 1998.

STUDY DESIGN

Records of all 500- to 800-g infants born at North Shore University Hospital during 1990-1998 were reviewed to determine demographic data, survival by weight and gestational age (GA), obstetric features, neonatal morbidity, and short-term neurologic/radiographic/neurosensory outcome. Newborn infants were grouped into three triennia: 1990-1992, 1993-1995, and 1996-1998 and compared across time.

RESULTS

Of the 173 infants admitted to the neonatal intensive care unit, 112 survived. Improved survival was documented: 40% in 1990-1992, 73% in 1993-1995, and 81% in 1996-1998 (p < 0.0001). Improved survival was also noted in each of the three weight cohorts, as well as in infants < or =26 weeks GA. An increased use of antenatal corticosteroids and increased number of deliveries by cesarean section (C/S) were noted across time. The incidence of 0 to 3 Apgar scores at both 1 and 5 minutes decreased across time. Necrotizing enterocolitis in survivors and expected short-term neurologic/radiographic/neurosensory outcome improved between 1990-1992 and 1996-1998, with a trend toward reduced IVH grade III to IV. The incidence of other neonatal morbidities did not change throughout the time period.

CONCLUSIONS

The data document that survival rates continued to improve for 500- to 800-g infants throughout the 1990s. This was concurrent with an increase in "low-risk, expected normal" infants, increased number of deliveries by C/S, decreased incidence of low Apgar scores at both 1 and 5 minutes, and an increased use of antenatal corticosteroids.

Neonatal survival rates in 860 singleton live births at 24 and 25 weeks gestational age. A Canadian multicentre study

OBJECTIVE

To determine the current survival rate of singleton living newborns born at gestational age of 24 and 25 weeks, using obstetric factors available to the physician before birth.

DESIGN

Retrospective study of all live births in 13 of 17 Canadian tertiary centres. Population All singleton live births without congenital abnormalities.

METHODS

During the years 1991-1996, data were abstracted from clinical databases and charts of 860 live births, in 13 of the 17 tertiary centres in Canada, all with major neonatal intensive care units. Newborn survival was defined as alive at discharge from neonatal intensive care unit. Abstracted elements included gestational age, maternal antenatal corticosteroid treatment, birthweight, gender, fetal presentation and mode of delivery.

RESULTS

Average survival rates increased from 56.1% at 24 weeks (n = 406) to 68.0% at 25 weeks (n = 454). Survival rates ranged from 53.1% at day 168 to 81.6% at day 181 (r = 0.802, P < 0.05). Steroid administration improved the survival rates at 24 and 25 weeks compared with that of unexposed fetuses, respectively (58.9% vs 41.8%; OR 1.70; 95% CI 1.03-2.08 and 74.2% vs 56.8%; OR 2.19; 95% CI 1.41-3.38). Caesarean delivery for breech presentation improved survival compared with vaginal delivery, both at 24 and 25 weeks (56.1% vs 36.0%; OR 2.19; 95% CI 1.10-4.34, and 68.7% vs 55.2% OR 1.78; 95% CI 0.093-3.43). Female neonates displayed better survival rates (59.6% vs 52.1% OR 1.36; 95% CI 0.92-2.01, and 72.6% vs 63.1% OR 1.51; 95% CI 1.02-2.25) at 24 and 25 weeks, respectively. Explanatory regression model confirmed these factors as prognostic variables associated with survival.

CONCLUSIONS

This extensive collaborative study confirms that several prognostic factors, known before birth, including gestational age in days, steroid treatment, mode of presentation and fetal sex may help obstetricians, neonatologists and parents in their decision-making process at 24 and 25 weeks of pregnancy.

Rehospitalization of extremely-low-birth-weight infants in first 2 years of life

AIMS

To determine whether (1) chronic lung disease (CLD) is the prime reason for extremely-low-birth-weight (ELBW) infant readmission during the first 2 years of life, (2) surfactant and other advanced therapies have reduced ELBW infant readmissions, (3) home oxygen therapy (HOT) is efficacious for this group.

STUDY DESIGN

The hospital records of these ELBW infants were reviewed retrospectively. Data on age, diagnosis, treatment, and duration of each hospitalization were compiled and analyzed for their association to CLD and to readmission for CLD and other reasons.

SUBJECTS

All 60 surviving infants with a birth body weight of less than 1001 g (ELBW) born from January 1993 to February 1998 were followed up to 2 years (mean 20.4 +/- 7.4 months) to evaluate their respiratory outcome.

RESULTS

Forty-two percent of these infants developed CLD. Upon discharge from the hospital, 28% (7/25) of the patients were given HOT for a median period of 60 days. Of the 47 ELBW infants who were studied the entire 2-year period, 72% were readmitted. Infants with CLD were readmitted more frequently (p=0.045) and had longer hospital stays during the first 2 years of life (p=0.034) than those without CLD. Respiratory illness was the main reason for readmission (55%) of these ELBW infants. The incidence of readmission due to respiratory tract infection was not significantly different in infants with CLD (61%) and infants without respiratory complications (44%) (p=0.159).

CONCLUSIONS

Infants with CLD (whether receiving HOT or not) showed no higher readmission rate due to respiratory infection, but the HOT group did have higher morbidity. The premature lung itself rather than the presence of CLD, as we would expect, makes ELBW infants more prone to readmission for respiratory illness.

Comparison of management strategies for extreme prematurity in New Jersey and the Netherlands: outcomes and resource expenditure

OBJECTIVE

To quantify differences in resource expenditure in the perinatal period and long-term outcome of extremely premature infants who received systematically different approaches to neonatal intensive care.

METHODS

Perinatal management, mortality, prevalence of disabling cerebral palsy (DCP), and resource expenditure of 2 population-based inception cohorts of extremely premature infants born in the mid-1980s were compared. Electronic fetal monitoring, tocolysis, cesarean section delivery, and assisted ventilation were used to characterize management approaches. Participants included all live births at 23 to 26 weeks' gestation in a 3-county area of central New Jersey (NJ) from 1984 to 1987 (N = 146) and throughout the Netherlands (NETH) in 1983 (N = 142). Mortality and the prevalence of DCP were the primary outcomes. Numbers of hospital days with and without assisted ventilation were the measures of resource expenditure.

RESULTS

Electronic fetal monitoring (100% vs 38%), cesarean section (28% vs 6%), and assisted ventilation (95% vs 64%) were all more commonly used in NJ than in NETH. Ten percent of NJ deaths occurred without assisted ventilation, compared with 45% of Dutch deaths. A total of 1820 ventilator days were expended per 100 live births in NJ, compared with 448 in NETH. The increase in the number of nonventilator days (3174 vs 2265 days per 100 live births) did not reach statistical significance. Survival to age 2 (46 vs 22%) and the prevalence of DCP among survivors (17.2 vs 3.4%) were significantly greater in NJ at age 2 than in NETH at age 5.

CONCLUSIONS

Near universal initiation of intensive care in NJ, compared with selective initiation of intensive care in NETH, was associated with 24.1 additional survivors per 100 live births, 7.2 additional cases of DCP per 100 live births, and a cost of 1372 additional ventilator days per 100 live births.

The outcome of extreme prematurity

Significant advances in perinatology and neonatology in the last decade have resulted in increased survival of extremely premature infants. Survival rates for infants born in tertiary perinatal and neonatal care centers in the United States in the 1990s increase with each week of gestational age from 22 through 26 weeks. Reported survival rates at 22 weeks range from 0% to 21% in the few reporting studies. Reported survival rates at 23 and 24 weeks range from 5% to 46% and from 40% to 59%, respectively. These may not be the maximum survival rates possible because at these gestational ages information is either insufficient to determine that obstetric and neonatal intensive care strategies to maximize neonatal survival were used or it is specified that such strategies were not used. Reported survival rates at 25 and 26 weeks range from 60% to 82% and from from 75% to 93%, respectively. The literature regarding the prevalence of major neurodevelopmental disabilities among extremely premature survivors in the last 25 years is heteogeneous, and the reported prevalances of major disability vary much more than do survival rates. However, the majority of extremely premature infants who survive will be free of major disability. Overall, approximately one fifth to one quarter of survivors have at least one major disability-impaired mental development, cerebral palsy, blindness, or deafness. Impaired mental development is the most prevalent disability (17%-21% [95% CI] of survivors affected), followed by cerebral palsy (12%-15% of survivors affected). Blindness and deafness are less common (5% to 8% and 3% to 5% of survivors affected, respectively). Approximately one half of disabled survivors have more than one major disability. Based on studies of infants less than 750 to 1,000 grams birth weight, it can be anticipated that approximately another half of all extremely premature survivors will have one or more subtle neurodevelopmental disabilities in the school and teenage years. There is little evidence to suggest that long-term neurodevelopmental outcome has changed from the late 1970s to the early 1990s or with increasing survival. Survival of individual extremely premature infants cannot be accurately predicted in the immediate perinatal period. Major disability cannot be accurately predicted for individual survivors during the course in the newborn intensive care unit.

A national short-term follow-Up study of extremely low birth weight infants born in Finland in 1996-1997

OBJECTIVES

The aims of this prospective nationwide investigation were to establish the birth rate, mortality, and morbidity of extremely low birth weight (ELBW) infants in Finland in 1996-1997, and to analyze risk factors associated with poor outcome.

PARTICIPANTS AND METHODS

The study population included all stillborn and live-born ELBW infants (birth weight: <1000 g; gestational age: at least 22 gestational weeks [GWs]), born in Finland between January 1, 1996 and December 31, 1997. Surviving infants were followed until discharge or to the age corresponding with 40 GWs. National ELBW infant register data with 101 prenatal and postnatal variables were used to calculate the mortality and morbidity rates. A total of 32 variables were included in risk factor analysis. The risk factors for death and intraventricular hemorrhage (IVH) of the live-born infants as well as for retinopathy of prematurity (ROP) and oxygen dependency of the surviving infants were analyzed using logistic regression models.

RESULTS

A total of 529 ELBW infants (.4% of all newborn infants) were born during the 2-year study. The perinatal mortality of ELBW infants was 55% and accounted for 39% of all perinatal deaths. Of all ELBW infants, 34% were stillborn, 21% died on days 0 through 6, and 3% on days 7 though 28. Neonatal mortality was 38% and postneonatal mortality was 2%. Of the infants who were alive at the age of 4 days, 88% survived. In infants surviving >12 hours, the overall incidence of respiratory distress syndrome (RDS) was 76%; of blood culture-positive septicemia, 22%; of IVH grades II through IV, 20%; and of necrotizing enterocolitis (NEC) with bowel perforation, 9%. The rate of IVH grades II through IV and NEC with bowel perforation decreased with increasing gestational age, but the incidence of RDS did not differ significantly between GWs 24 to 29. A total of 5 infants (2%) needed a shunt operation because of posthemorrhagic ventricular dilatation. Two hundred eleven ELBW infants (40% of all and 60% of live-born infants) survived until discharge or to the age corresponding with 40 GWs. The oxygen dependency rate at the age corresponding to 36 GWs was 39%, and 9% had ROP stage III-V. Neurological status was considered completely normal in 74% of the surviving infants. The proportions of infants born at 22 to 23, 24 to 25, 26 to 27, and 28 to 29 GWs with at least one disability (ROP, oxygen dependency, or abnormal neurological status) at the age corresponding to 36 GWs were 100%, 62%, 51%, and 45%, respectively. Birth weight <600 g and gestational age <25 GWs were the independent risks for death and short-term disability. The primary risk factor for IVH grades II through IV was RDS. Low 5-minute Apgar scores predicted poor prognosis, ie, death or IVH, and antenatal steroid treatment to mothers with threatening premature labor seemed to protect infants against these. Some differences were found in the mortality rates between the 5 university hospital districts: neonatal mortality was significantly lower (25% vs 44%) in one university hospital area and notably higher (53% vs 34%) in another area. Furthermore, significant differences were also found in morbidity, ie, oxygen dependency and ROP rates. Differences in perinatal (79% vs 45%) and neonatal (59% vs 32%) mortality rates were found between secondary and tertiary level hospitals.

CONCLUSION

Our study shows that even with modern perinatal technology and care, intrauterine and early deaths of ELBW infants are common. The outcome of infants born at 22 to 23 GWs was unfavorable, but the prognosis improved rapidly with increasing maturity. The clear regional and hospital level differences detected in survival rates and in short-term outcome of ELBW infants emphasizes that the mortality and morbidity rates should be continuously followed and that differences should be evaluated in perinatal audit procedures. (ABSTRACT TRUNCATED)

Gestational age- and birthweight-specific declines in infant mortality in Canada, 1985-94. Fetal and Infant Health Study Group of the Canadian Perinatal Surveillance System

We studied infant mortality rates in Canada within specific gestational age and birthweight categories after using probabilistic techniques to link information in Statistics Canada's live births data base (1985-94) with that in the death data base (1985-95). Gestational age- and birthweight-specific mortality rates in 1992-94 were contrasted with those in 1985-87 with changes expressed in terms of relative risks with 95% confidence intervals [CI]. Statistically significant reductions in infant mortality were observed beginning at 24-25 weeks of gestation and extended across the gestational age range to post-term births. Crude infant mortality rates, infant mortality rates among those > or = 500 g and among those > or = 1000 g decreased by 22%, 25% and 26%, respectively, from 1985-87 to 1992-94. The magnitude of the reductions in infant mortality rates ranged from 14% [95% CI 7, 21%] at 24-25 weeks of gestation to 40% [95% CI 31, 47%] at 28-31 weeks. Almost all reductions in gestational age- and birthweight-specific infant mortality between 1985-87 and 1992-94 were due to approximately equal reductions in neonatal and post-neonatal mortality. Live births > or = 42 weeks of gestation did not follow this rule; post-neonatal mortality rates among such live births decreased significantly by 51% [95% CI 26, 68%], although neonatal mortality rates showed no significant change. The mortality reductions observed across the gestational age and birthweight range are probably a consequence of specific clinical interventions complementing improvements in fetal growth. Temporal changes in the outcome of post-term pregnancies need to be carefully examined, especially in relation to recent changes in the obstetric management of such pregnancies.

Ethical issues in the delivery room: resuscitation of extremely low birth weight infants

The neonatal team attending high-risk deliveries is often faced with difficult ethical decisions concerning aggressive cardiopulmonary resuscitation for infants of 22-24 weeks gestational age (GA). These decisions are often based on the ethical principles of beneficence, nonmaleficence, justice, futility, autonomy, quality of life, and best interests and legal rights of the infant. Three delivery room recommendations are discussed along with their legal and ethical considerations. The perinatal and neonatal intensive care nurse must understand the moral, ethical, legal, and professional responsibilities and their effect on her/his own judgment decisions. These, in turn, will affect the infants, their parents, and other colleagues.

Survival of the extremely preterm infant in North America in the 1990s

Survival of extremely premature infants has been significantly higher in the last decade than previously, and may well have improved during this time. The majority of infants greater than or equal to 25 weeks' gestation survive today. Survival of infants 23 and 24 weeks' gestation is significantly lower, but is by no means negligible. Reports of survival of infants less than 23 weeks or less than 500-g birth weight are not unique. Moreover, the maximum survival of infants less than or equal to 25 weeks possible with current state-of-the-art care is not known. Currently available data do not allow survival of the individual extremely low-birth weight or extremely premature infant to be predicted with clinically acceptable accuracy. The concept of a limit of viability is vague and clinically and ethically simplistic. The provision of neonatal intensive care is not necessarily beneficial or justified merely because it affords some minimal chance of survival. This phrase should not be used to summarize the complex issues involved in balancing maternal and neonatal risks and benefits of intrapartum and neonatal care of the extremely low-birth weight or the extremely premature fetus and infant, the suffering of the infant and family, parental values and autonomy, and consumption of limited communal resources. It should be deleted from our vocabulary.