Perinatal factors and adverse outcome in extremely low birthweight infants

Outcomes of neonatal hypothermia among very low birth weight infants: a Meta-analysis

BACKGROUND

Neonatal admission hypothermia (HT) is a frequently encountered problem in neonatal intensive care units (NICUs) and it has been linked to a higher risk of mortality and morbidity. However, there is a disparity in data in the existing literature regarding the prevalence and outcomes associated with HT in very low birth weight (VLBW) infants. This review aimed to provide further summary and analyses of the association between HT and adverse clinical outcomes in VLBW infants.

METHODS

In July 2020, we conducted this review according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A systematic database search was conducted in MEDLINE (PubMed), Google Scholar, ScienceDirect, World Health Organization Virtual Health Library, Cochrane Library databases, and System for Information on Grey Literature in Europe (SIGLE). We included studies that assessed the prevalence of HT and/or the association between HT and any adverse outcomes in VLBW infants. We calculated the pooled prevalence and Odds Ratio (OR) estimates with the corresponding 95% Confidence Interval (CI) using the Comprehensive meta-analysis software version 3.3 (Biostat, Engle-wood, NJ, USA; http://www.Meta-Analysis.com ).

RESULTS

Eighteen studies that fulfilled the eligibility criteria were meta-analyzed. The pooled prevalence of HT among VLBW infants was 48.3% (95% CI, 42.0-54.7%). HT in VLBW infants was significantly associated with mortality (OR = 1.89; 1.72-2.09), intra-ventricular hemorrhage (OR = 1.86; 1.09-3.14), bronchopulmonary dysplasia (OR = 1.28; 1.16-1.40), neonatal sepsis (OR = 1.47; 1.09-2.49), and retinopathy of prematurity (OR = 1.45; 1.28-1.72).

CONCLUSION

Neonatal HT rate is high in VLBW infants and it is a risk factor for mortality and morbidity in VLBW infants. This review provides a comprehensive view of the prevalence and outcomes of HT in VLBW infants.

Predictors of Mortality after Primary Discharge from Hospital in Patients with Esophageal Atresia

OBJECTIVE

To describe esophageal atresia mortality rates and their associations in our cohort.

STUDY DESIGN

Patients with esophageal atresia, managed at The Royal Children's Hospital, Melbourne (1980-2018), who subsequently died, were retrospectively identified from the prospective Nate Myers Oesophageal Atresia database. Data collected included patient and maternal demographics, vertebral anomalies, anorectal malformations, cardiovascular anomalies, tracheoesophageal fistula, renal anomalies, and limb defects (VACTERL) associations, mortality risk factors, and preoperative, operative, and postoperative findings. Mortality before discharge was defined as death during the initial admission.

RESULTS

A total of 88 of the 650 patients (13.5%) died during the study period; mortality before discharge occurred in 66 of the 88 (75.0%); mortality after discharge occurred in 22 of the 88 (25.0%). Common causes of mortality before discharge were palliation for respiratory anomalies (15/66 [22.7%]), associated syndromes (11/66 [16.7%]), and neurologic anomalies (10/66 [15.2%]). The most common syndrome leading to palliation was trisomy 18 (7/66 [10.6%]). Causes of mortality after discharge had available documentation for 17 of 22 patients (77.3%). Common causes were respiratory compromise (6/17 [35.3%]), sudden unexplained deaths (6/17 [35.3%]), and Fanconi anemia (2/17 [11.8%]). Of the patients discharged from hospital, 22 of 584 (3.8%) subsequently died. There was no statistical difference in VACTERL association between mortality before discharge (31/61 [50.8%]) and mortality after discharge (11/20 [55.0%]), nor in incidence of twins between mortality before discharge (8/56 [14.3%]) and mortality after discharge (2/18 [11.1%]).

CONCLUSIONS

We identified predictors of mortality in patients with esophageal atresia in a large prospective cohort. Parents of children with esophageal atresia must be counselled appropriately as to the likelihood of death after discharge from hospital.

Improving perinatal regionalization by predicting neonatal intensive care requirements of preterm infants: an EPIPAGE-based cohort study

OBJECTIVE

Perinatal regionalization has been organized into 3 ascending levels of care, fitting increasing degrees of pathology. Current recommendations specify that very premature infants be referred prenatally to level III facilities, yet not all very preterm neonates require level III intensive care. The objective of our study was to determine the antenatal factors that, in association with gestational age, predict the need for neonatal intensive care in preterm infants, to match the size of birth with the level of care required.

METHODS

Data were analyzed from a cohort of very preterm infants born in nine French regions in 1997. We defined the need for neonatal intensive care as follows: (1) the requirement for specialized management (mechanical ventilation for >48 hours, high frequency oscillation, or inhaled nitric oxide) or (2) poor outcome (transfer to a level III facility within the first 2 days of life or early neonatal death). Triplet pregnancies and pregnancies marked by fetal malformations or intensive care requirements for the mother before delivery were excluded.

RESULTS

We focused our study on 1262 neonates aged 30, 31 and 32 weeks' gestation, where the need for intensive care was 42.8%, 33.2%, and 22.8%, respectively. Multivariate analysis showed that the risk factors for intensive care requirement with low gestational age were twin pregnancies, maternal hypertension, antepartum hemorrhage, infection, and male gender. Antenatal steroid therapy and premature rupture of membranes were protective factors against intensive care requirement.

CONCLUSION

Infants <31 weeks' gestation should be referred to level III facilities. From 31 weeks' gestation, some infants can be safely handled in level IIb facilities. However, the quality of perinatal regionalization may only be fully assessed by long-term follow-up.

Preterm birth: a cost benefit analysis

Advances in prenatal and perinatal treatment of preterm and VLBW infants have dramatically increased the survival rate of these infants. Some interventions decrease long term sequelae associated with preterm birth, making them more cost-effective than other treatments. This paper reviews the cost-effectiveness of therapies targeted to protect the preterm brain. Birth in a center with a NICU improves survival and decreases the rate of severe neurologic disability. Administration of antenatal steroids increases survival and decreases rates of periventricular hemorrhage, periventricular leukomalacia, necrotizing enterocolitis, respiratory distress syndrome, and severe disability. Administration of antenatal steroids decreases costs per additional survivor. Addition of surfactant to the treatment of PT infants has also decreased treatment costs. Administration of surfactant is beneficial for symptomatic RDS but recognizes a greater benefit when given to infants younger than 30 weeks gestation prophylactically. Treatment with prophylactic indomethacin decreases the rate of intraventricular hemorrhage and results in cost savings in survivors. Postnatal administration of dexamethasone can lead to severe disability when administered before 7 to 10 days of life. Postnatal dexamethasone does not increase survival or decrease rates of chronic lung disease.

Survival of very preterm infants: Epipage, a population based cohort study

OBJECTIVE

To evaluate the outcome for all infants born before 33 weeks gestation until discharge from hospital.

DESIGN

A prospective observational population based study.

SETTING

Nine regions of France in 1997.

PATIENTS

All births or late terminations of pregnancy for fetal or maternal reasons between 22 and 32 weeks gestation.

MAIN OUTCOME MEASURE

Life status: stillbirth, live birth, death in delivery room, death in intensive care, decision to limit intensive care, survival to discharge.

RESULTS

A total of 722 late terminations, 772 stillbirths, and 2901 live births were recorded. The incidence of very preterm births was 1.3 per 100 live births and stillbirths. The survival rate for births between 22 and 32 weeks was 67% of all births (including stillbirths), 85% of live births, and 89% of infants admitted to neonatal intensive care units. Survival increased with gestational age: 31% of all infants born alive at 24 weeks survived to discharge, 78% at 28 weeks, and 97% at 32 weeks. Survival among live births was lower for small for gestational age infants, multiple births, and boys. Overall, 50% of deaths after birth followed decisions to withhold or withdraw intensive care: 66% of deaths in the delivery room, decreasing with increasing gestational age; 44% of deaths in the neonatal intensive care unit, with little variation with gestational age.

CONCLUSION

Among very preterm babies, chances of survival varies greatly according to the length of gestation. At all gestational ages, a large proportion of deaths are associated with a decision to limit intensive care.

Educational and behavioural problems in babies of 32-35 weeks gestation

AIM

To identify incidence of school and behaviour problems at age 7 years in children born between 32 and 35 weeks gestation, and investigate perinatal risk factors.

METHOD

The study population consisted of all children born at 32-35 weeks gestation to mothers resident in Oxfordshire in 1990. General practitioners, parents, and teachers were asked about health, behaviour, and education by postal questionnaire. Teachers rated children on level of function in six areas using a five point scale. They also completed the Strengths and Difficulties behaviour questionnaire. Perinatal risk factors were identified for children with poor school performance using a univariate and multivariate analysis.

RESULTS

Teacher responses were obtained for 117 (66%) of the 176 children in the cohort. Twenty nine (25%) required support from a non-teaching assistant, five (4%) had required a statement of special educational needs, and three (3%) were at special school. Poor outcome was reported for 32% in writing, 31% in fine motor skills, 29% in mathematics, 19% in speaking, 21% in reading, and 12% in physical education. On the behaviour questionnaire, 19% of the cohort achieved an abnormal hyperactivity score (population norm 10%). Multivariate analysis showed perinatal variables that remained significant, independent of other variables; they were discharge from the special care baby unit > 36 weeks postconceptional age (odds ratio 4.15; 95% confidence interval 1.43 to 12.05) and male sex (odds ratio 3.88; 95% confidence interval 1.42 to 10.6).

CONCLUSION

Up to a third of children born between 32 and 35 weeks gestation may have school problems. As there are larger numbers in this gestational category compared with smaller babies, this finding has implications for educational services.

Outcomes of extremely premature infants related to their peak serum bilirubin concentrations and exposure to phototherapy

OBJECTIVES

To analyze, in extremely low birth weight infants, associations between peak bilirubin concentration and evidence of brain damage, and between peak bilirubin concentration and blindness attributable to retinopathy of prematurity.

METHODS

Retrospective study of 128 infants of </=800 g birth weight and </=27 weeks gestation born between 1980 and 1989 and discharged from a tertiary neonatal intensive care unit. After screening analyses, multivariable analyses were conducted to identify associations between blindness and peak bilirubin concentration (dichotomized at different levels to create 3 binary variables), and between severe adverse neurodevelopmental outcome at 18 months postterm age and peak bilirubin levels.

RESULTS

Of 128 18-month survivors, 15 had severe visual loss attributable to retinopathy of prematurity, 21 had neurodevelopmental deficit, and 5 were deaf. Visual loss was significantly associated with low-peak serum bilirubin concentration (<9.4 mg/dL (<160 micromol/L) versus >/=9.4 mg/dL (odds ratio [OR] confidence interval [CI] 4.48 [1.15-17.43])), low gestational age (OR [CI] per week 1.95 [1.05-3.63]), and longer duration of phototherapy (OR [CI] per 10 hours 1.17 [1.02-1.33]). The association of neurodevelopmental impairment with grades 3 and 4 intraventricular hemorrhage was statistically significant (OR 5.39 [1.83-15.84]), but with high-peak serum bilirubin concentration >/=11.7 mg/dL (>/=200 micromol/L), was not significant (OR 2.89 [0. 87-9.53]).

CONCLUSIONS

In these infants, prolonged phototherapy and low-peak serum bilirubin concentrations were associated with severe visual loss attributable to retinopathy of prematurity. The findings should be interpreted with caution until the evidence is reinforced in other patient populations.

Survival of very low birthweight and very preterm infants in a geographically defined population

OBJECTIVE

To determine in a geographically defined population 1 year survival of infants with a birthweight of less than 1500 g or gestational age less than 32 weeks, and to establish the effect of postnatal age on predicted survival.

DESIGN

Cohort analysis of 72,427 births to Welsh residents in 1993-94. Deaths were identified using the All Wales Perinatal Survey, a population-based surveillance of mortality between 20 weeks of gestation and 1 year of age.

MAIN OUTCOME MEASURES

Birthweight- and gestation-specific infant mortality, and the effect of postnatal age, gender, and multiple pregnancy on predicted survival.

RESULTS

In normally formed infants 1 year survival at 24-25 weeks gestation was 35%, compared to 75% at 27-28 weeks, and 95% at 30-31 weeks. In infants with a birthweight of 500-699 g 1 year survival was 18% compared to 70% at 800-999 g, and 97% at 1300-1499 g. The chances of survival improved markedly with increasing postanatal age; at 24-25 weeks gestation it was 35% at birth, 50% at 12 h. 66% at 7 days and 78% at 4 weeks. Infant mortality was higher in males, but multiple pregnancy had no effect.

CONCLUSIONS

Up-to-date birthweight- and gestation-specific survival rates are essential for predicting the outcome of a newborn infant. The rapid change in the chances of survival with increasing postnatal age emphasises especially the importance of revising the prediction as the infant gets older, particularly during the first few days of life.

Secular changes in the outcomes to eighteen to twenty-four months of age of extremely low birth weight infants, with adjustment for changes in risk factors and severity of illness

OBJECTIVES

To analyze secular changes in the rates of death and of major impaired outcome in surviving outborn infants who weighted < or = 800 gm at birth and were admitted in 1980 to 1989, with adjustment for changes in risk factors and severity of illness around the time of birth; and to identify changes in these factors that might explain changes in outcomes.

DESIGN

Retrospective cohort study with follow-up to a minimum of 18 months of postterm age. After preliminary screening, multivariate models of association between risk/severity of illness factors and outcomes were constructed, validated, and used to adjust outcomes (death and major impairment to 18 to 24 months of age).

SETTING

Regional neonatal intensive care unit for referral of "outborn" infants.

PATIENTS

Two hundred eighty-seven consecutively admitted infants who weighted < or = 800 gm at birth (97% follow-up).

RESULTS

The death rate during the 1980s did not fall significantly (p adjusted for risk factors = 0.115). The major impairment rate fell (odds ratio, 0.24 (95% confidence interval, 0.10, 0.60); p = 0.002, adjusted for delivery route and respiratory failure measures), mainly because of a reduced rate of blindness, not attributable to cryotherapy. The risk factors that improved and were possibly related to the reduced impairment rate were blood pH and glucose concentration, and serum sodium concentration in the first 48 hours of life.

CONCLUSIONS

Despite an increasing selection for referral of less mature and more severely ill outborn babies near the "limit of viability," and despite more aggressive care, the rate of major impairment fell significantly during the 1980s. This trend was enhanced by adjustment for severity of illness. The fall was attributable to a reduced rate of blindness, and was associated with evidence of improved control of physiologic balance after birth.

Clinical significance of absent or reversed end diastolic velocity waveforms in umbilical artery

Doppler ultrasound provides a non invasive method to assess fetal haemodynamics. We looked at the outcome of doppler velocimetry of the umbilical artery in three groups of pregnancies: those with positive end diastolic velocities (PED; n = 214), absent end diastolic velocities (AED; n = 178) and reversed end diastolic velocities (RED; n = 67). We collected our data from 9 European centers. Logistic regression showed that compared with pregnancies with hypertension only, pregnancies complicated by intra uterine growth retardation (IUGR) had a higher risk of developing absent or reversed end diastolic velocity waveforms (ARED) flow. ARED flow in the umbilical artery (odds ratio: OR = 3.1). Pregnancies complicated by both IUGR and hypertension had an even higher risk (OR = 7.4). Maternal age and smoking habits did not influence the risk of developing ARED flow. The overall perinatal mortality rate was 28%. Significantly more neonates in the ARED flow group needed admittance to the neonatal intensive care unit (PED group 60%, AED group 96%, RED group 98%). The OR for perinatal mortality in pregnancies complicated by AED flow was 4.0 and in RED flow was 10.6, compared with PED flow, even after adjustment for menstrual age. ARED flow in the umbilical artery did not influence the risk of respiratory distress syndrome or necrotising enterocolitis of the neonate, but ARED flow significantly influenced the risk of cerebral haemorrhage, anaemia, or hypoglycaemia. We advise that pregnancies complicated by IUGR and/or hypertension should be followed up with doppler velocimetry to trace utero-placental problems as early as possible. A caesarean section is recommended in all pregnancies complicated by ARED flow if the gestational age and predicted neonatal weight can be handled by the local neonatal intensive care unit.

The cognitive outcome of very preterm infants may be poorer than often reported: an empirical investigation of how methodological issues make a big difference

The effects of relying on outmoded IQ-test norms and the use of arbitrary classifications of developmental delay on estimates of cognitive impairment of very preterm infants (VPI) was evaluated in a prospective population study. Cognitive assessments included the Griffiths test at 5 and 20 months and the Columbia Mental Maturity Scales (CMM) and a vocabulary test (Aktiver Wortschatz Test, AWST) at 56 months of age. Rates of cognitive impairment of 321 very preterm infants (VPI; < 32 weeks gestation or < 1500 g birth weight) were determined according to the published test norms, to scores of a full-term control group (FC n = 321), and to scores from a representative sample of children (NC n = 431) of the same birth cohort. IQ-scores were higher in the FC and NC children than in the original standardisation sample (SS). Using the concurrent test norms (FC, NC) up to 2.4 times more VPI were identified as seriously impaired (<-2 SD) than if the published (outdated) norms were used. Serious developmental delay was underestimated when arbitrary (e.g. DQ < 70) rather than across age comparable definitions (DQ <-2 SD) were used. VPI study drop-outs had mothers with lower educational qualifications and poorer cognitive developmental scores at 5 or 20 months of age. In conclusion, a lack of appropriate control groups and use of arbitrary criteria for judging serious delay leads to large underestimations of cognitive impairment in VPI. Findings from previous uncontrolled studies of VPI need re-interpretation.

Outcome of infants born preterm, with special emphasis on extremely low birthweight infants

The outcome of extremely low birthweight (ELBW) infants has been reviewed from published articles and up-to-date data from Japan. The mortality rate of these infants declined significantly from over 90% to below 50% after the introduction of intensive care in the 1970s, but the incidence of major neurological sequelae remained steady at around 20%. Similarly, the incidence of major neurological sequelae did not increase along with the decrement of birthweight, although the mortality rate increased significantly. Long-term follow-up of ELBW children until school age has revealed poor school performance in spite of the absence of major neurological sequelae and the attainment of average intelligence quotient scores. Physical growth is retarded initially but generally catches up by the age of 8-9 years. In Japan, the neonatal mortality rate of ELBW infants declined from 56% in 1981 to 25% in 1989 with an increased birth rate of ELBW infants. In ELBW infants cared for at Tokyo Women's Medical College during 1984-90, the survival rate was 112 out of 134 (84%) and the incidence of major neurological sequelae was 15 out of 87 (17%) at 1-8 years old. The viability limit of ELBW infants has been discussed based on recent data. As a result of the rapid progress of medical care of ELBW infants, their viability limit as defined in the Eugenic Protection Law in Japan was amended from 24 completed weeks of gestation to 22 completed weeks in 1991.

Evaluation of care for the preterm infant: review of literature on follow-up of preterm and low birthweight infants. Report from the collaborative Project on Preterm and Small for Gestational Age Infants (POPS) in The Netherlands

Since the introduction of neonatal intensive care in the 1960s, mortality in very preterm and very low birthweight infants has been decreasing steadily. Consequently, interest in the outcome of surviving infants is growing. Restriction of health care resources has stressed the need for information concerning the effect of individual treatment components on mortality and morbidity. Concern about the quality in apparently normal survivors has been increasing as well. The current flood of papers on these subjects illustrates the interest in these issues. The first part of this paper reviews the methodology used in follow-up studies in the past decades. It aims at methodological problems that hamper comparison between studies and preclude unequivocal conclusions. New treatment techniques seldom were but should be evaluated by randomised trials. To monitor the combined effects of changing obstetric and neonatal techniques on perinatal outcome, studies in geographically defined populations are recommended using data from early pregnancy until at least preschool age. Comparability of outcomes could be enhanced by international agreement on standardisation of assessment methods and outcome measures. In the second part the results concerning gestational age- and birthweight-specific mortality, impairments and disabilities and the risk factors for such disorders are discussed. Increased survival of even the tiniest infants is clearly established. This increase in survival has not yet been accompanied by an apparent increase in major morbidity. However, many minor impairments are reported, occurring often in combination and predisposing these children to deviations of normal development. Important changes in the manifestation of brain damage appear to occur during development. These findings stress the importance of long-term follow-up studies.

The male disadvantage in very low birthweight infants: does it really exist?

In a nationwide collaborative study in the Netherlands, perinatal and follow up data were collected on 1338 liveborn very preterm (less than 32 weeks) and/or very low birthweight (VLBW) infants (less than 1500 g). In this group, the mortality risk was similar for both male and female infants. The handicap risk, however, was significantly greater for boys than for girls. This finding could not be explained as being due to the well-known delay in lung maturation in male infants as in idiopathic respiratory distress syndrome and need of assisted ventilation.

Infants weighing 1,000 g or less at birth. Outcome at 8-11 years of age

34 long-term survivors of a five-year period (1977-1981) weighing 1,000 g or less at birth were followed-up at 8-11 years of age. Three (8.8%) children had severe functional handicap, 7 (20.6%) had moderate impairments with the need of special schooling. Twenty-four (70.6%) attended normal school but 7 (20.6%) with need of special help. The rate of survival was 30% at the single regional intensive centre where this cohort of infants were cared for. Handicapped infants differed significantly from infants with good prognosis in their neonatal requirements for oxygen therapy and in pathological conditions such as birth asphyxia and recurrent apneic spells but no differences in birthweight, gestational age, route of delivery, maternal age, social class, proportions below the tenth percentile and sex were found.

The behaviour of 3-year-old children who were born preterm

The behaviour of 3-year-old children born preterm was compared with that of full-term children of the same age. The preterm group were born between 32 and 37 weeks gestation, and weighed between 1500 g and 2500 g at birth, and thus (in comparison to even earlier, lower birthweight babies) comprised a 'low risk' group. The children and their mothers were interviewed at home and information obtained about the following: behaviour, the number of accidents requiring medical attention, language development, maternal mental health and demographic data. The preterm group did not show an excess of behaviour problems overall but they did show significantly more problems when certain individual behaviours were considered, namely sleep related problems, tempers and dependence. The preterm group had also had significantly more accidents. The nature of the behavioural differences suggested they represented styles of parental management rather than neurological impairment in the preterm group. There was no evidence of language delay in either group and no significant association between child behaviour and maternal mental health. This study showed that consideration of socioeconomic factors is important. Children from manual socioeconomic groups showed significantly more behaviour problems than children from non-manual groups, and mothers from manual groups had significantly poorer mental health.

Motor skills in extremely low birthweight children at the age of 6 years

Fifty three children aged 6 years old who had weighed less than 1251 g at birth without cerebral palsy and receiving mainstream education, were entered into a controlled study of motor skills. The index and control children were matched by age, sex, and school. The index group were considered by their teachers to have similar academic performances to their index group were considered by their teachers to have similar academic performances to their controls, although two index cases were receiving remedial teaching. On the test of motor impairment extremely low birthweight children had significantly more motor difficulties than controls. In addition, the index group had more minor neurological signs, lower intelligence quotients, and more adverse behavioural traits. The higher motor impairment scores among index children were independent of differences in intelligence quotient between the two groups. There was no association between impairment score and the presence or degree of periventricular haemorrhage or periventricular leucomalacia on neonatal cerebral ultrasound. Children with Apgar scores at five minutes of less than 7 had significantly higher impairment scores compared with those whose scores were 7 or more. Three perinatal factors (Apgar score at five minutes, neonatal septicaemia, and abnormal movements) explained 32% of the variance in impairment score at the age of 6 years. In children who do not have cerebral palsy perinatal factors may still be important in the development of motor skills. The presence of subtle neuromotor impairments at 6 years of age has implications for schooling that need further evaluation.

Clinical factors associated with adverse outcome for babies weighing 2000 g or less at birth

Using clinical factors, the probabilities of survival with and without major handicap were separately calculated by multiple logistic regression for 988 children who weighed 2000 g or less at birth and who were born in the period 1976-1980. For survivors weighing 501-1250 g in whom incidence of serious handicap was 21%, neonatal fits and the need for mechanical ventilation carried significantly increased risks of later serious handicaps. In contrast, for survivors weighing 1251-2000 g in whom the incidence of serious handicap was 6%, significant factors were spontaneous, uncomplicated preterm delivery, recurrent apnoea, and abnormal neonatal neurological findings. The probability of dying was assessed in two ways--firstly, using seven clinical factors available on admission to the neonatal unit, and secondly, using 10 perinatal and neonatal factors. Handicapped survivors had a perinatal risk between that of those babies who survived and that of those who died. Of the handicapped survivors, those with spastic diplegia and hemiplegia had been extremely low risk babies (medians 1.4% and 1.6%, respectively), whereas those with other impairments had much higher risks (range 17.5-38.1%). We postulate that certain impairments arise independently of clinical events, although most occur in children who had complicated perinatal courses.

Vaginally born low-risk preterm infants: fetal acidosis and outcome at 6 years of age

In a population of vaginally born low-risk preterm infants fetal acidosis (scalp pH less than 7.20) was found in 50% (6 out of 12) of infants of 29-33 weeks' gestational age (Group I) and in 9% (2 of 22) infants of 34-36 weeks' gestational age (Group II). At 6-7 years of age the children underwent a neurodevelopmental examination including a Griffith test. Five out of 6 Group I infants with fetal acidosis and 10 out of 20 Group II infants without fetal acidosis had minor or moderate neurodevelopmental problems. On the Griffith test Group II infants scored below Group I with more coordination and fine motor problems on the tested subscales. Fetal acidosis was more common in very preterm infants but cannot be used per se as a reliable indicator of long-term outcome.

Outcome at school age of children with birthweights of 1000 grams or less

A follow-up study was done of extremely low-birthweight infants (less than or equal to 1000g) born between 1976 and 1979, a period when aggressive intervention was not routine practice. The survival rate was 19 per cent. 44 of the 46 survivors were followed to a mean age of 6 1/2 years. By five years of age 23 of the 44 children had been admitted to hospital, mainly for surgery and respiratory problems. Eight of 31 five-year-old children were growth-retarded and five of 26 were microcephalic. Among 44 children, ophthalmological problems were found in nine cases and neurosensory impairments (cerebral palsy, deafness) in seven. 12 children were mentally handicapped or had impaired intelligence (IQ or DQ less than 85). Over-all, 14 of the 44 children had impairments, severe in four cases and moderate in 10. Mean verbal IQ was significantly lower than mean performance IQ. Among 37 children in school or in remedial programs, nine required special education and another 12 in regular classes either failed or had very poor results, or needed extra professional help. Only 16 of the children had no significant problems in school. These findings indicate that extremely low birthweight (less than or equal to 1000g) represents a major risk to life, health (hospital admissions), long-term growth, neurosensory integrity, cognitive development and learning potential.

Understanding and preventing perinatal, intracerebral, peri- and intraventricular hemorrhage

Antenatal anticipation of problem pregnancies and improvements in resuscitation and care of newborns have led to increasing survival of babies born prematurely. Nevertheless, the potential for neurologic handicaps is significant in this population of children, and the prevention of intracerebral, peri- and intraventricular hemorrhages and associated brain lesions remains a high priority. In this review, we consider the clinical problem of periventricular, intraventricular hemorrhage; means of diagnosis; the EEG and periventricular, intraventricular hemorrhage; sequelae; hypotheses of pathogenesis; experimental approaches to understanding periventricular, intraventricular hemorrhage; agents being tested for use in preventing hemorrhage; and future areas for research toward the prevention of hemorrhage and other neonatal brain lesions.

The extremely low birthweight infant: ethical issues in treatment

Survival and disability rates of extremely low birthweight infants have significantly improved. Since it is impossible to give an accurate prognosis at the time of birth, all such live births should be resuscitated and curative treatment, including the use of life support measures when appropriate, promptly initiated. In the event that medical facts indicate curative efforts are futile or lack compensating benefit, they should be discontinued and palliative treatment, which provides symptomatic relief and comfort, should be introduced. The attending neonatologist has the primary role as advocate for the infant and medical advisor to the parents, while the parents act as surrogates for their infant. The shift in emphasis from curative to palliative treatment requires medical consensus among all those involved in the care of the infant and consent from the parents closely involved in this widely shared decision. The role of infant bioethics committees is one of advisor and consultant to this decision-making process. Legislation needs to uphold the primary prejudice in favour of life while conceding that discontinuation of curative treatment, which is no longer effective, and the provision of palliative treatment, are appropriate medical decisions in exceptional cases.

Prognosis for infants born at 23 to 28 weeks' gestation

The survival and neurodevelopmental outcome of 356 extremely preterm infants born at 23 to 28 weeks' gestation were reported by week of gestation. Their corrected 1 year survival improved from 7% at 23 weeks to 75% at 28 weeks. The overall incidence of impairment was 19% and of major disability 12%. Boys had a significantly lower normal survival than girls. Multiple births had a significantly lower survival and higher incidence of impairment than singleton births. Predictions of outcome were made before delivery, after resuscitation, and at 1 week to aid the development of guidelines on when perinatal intensive care is justified, whether obstetric intervention for fetal reasons is warranted, and what initial and ongoing prognoses to give to parents. Intensive care for progressively smaller and more immature infants, many of whom were previously considered non-viable, needs to be carefully monitored by every perinatal centre.