Survival, cranial ultrasound and cerebral palsy in very low birthweight infants: 1980s versus 1990s

Objective : To determine the changes in the rates of survival, cranial ultrasound abnormalities and cerebral palsy in very low birthweight (VLBW) (birthweight 500–1499 g) infants between the early 1980s and the early 1990s.
Methodology : A cohort study of consecutive VLBW live births in one tertiary perinatal hospital during two distinct eras was performed at The Royal Women's Hospital, Melbourne, a level-III perinatal centre. Consecutive VLBW infants born over the 18-month period from 1 October 1980 ( n = 222), and over the 12-month period from 1 January 1992 ( n = 202) were identified. The main outcome measures were the proportions of live births surviving to 5 years of age, rates of cranial ultrasound abnormalities, and rates of cerebral palsy at 5 years of age.
Results : Over the 18 months from 1 October 1980, 68% (150/222) VLBW live births survived to 5 years of age. The survival rate rose substantially to 82% (165/202) during 1992 (odds ratio 2.1, 95% confidence interval 1.4–3.2). The survival rate increased over time more for those of 500–999 g birthweight than for those of 1000–1499 g birthweight. The rates of cerebroventricular haemorrhage (CVH) were similar in live births and survivors from both eras, as were the rates of cerebral palsy (7.5% in 1980–82; 7.8% in 1992) in survivors seen at 5 years of age. The positive predictive value of CVH for cerebral palsy was low, but cystic periventricular leucomalacia was followed by cerebral palsy in seven of eight survivors from the 1992 cohort.
Conclusions : Despite the increasing survival rate with improvements in perinatal care, including more antenatal steroid therapy and the introduction of exogenous surfactant, the rates of CVH and of cerebral palsy in survivors have not diminished.     

Risk factors for bronchopulmonary dysplasia in neonates born at ≤1500 g (1999–2009)

Background: Advances in perinatal care have improved the survival rate for very low‐birthweight (VLBW) infants in China. The incidence of bronchopulmonary dysplasia (BPD), however, has not been reduced. The objective of the present study was to identify the perinatal risk factors for BPD in neonates born at ≤1500 g. Methods: A retrospective analysis of data for neonates born at ≤1500 g between 1999 and 2009 in the neonatal intensive care unit (NICU) of Second Affiliated Hospital of Sun Yat‐Sen University, Guangzhou city, China, was carried out. Results: Out of a total of 11 506 live births, 3538 infants were admitted to level II nursery and NICU (level III nursery). Among 149 preterm infants born at ≤1500 g, 77.8% survived until day 28, and the incidence of BPD was 48.3%. Logistic regression analysis showed that gestational age (GA) ≤30 weeks (odds ratio [OR], 9.507; 95% confidence intervals [95%CI]: 2.604–34.707), maternal chorioamnionitis (OR, 41.987; 95%CI: 6.048–291.492), ventilation‐associated pneumonia (OR, 11.600; 95%CI: 2.847–47.268), and more than three blood transfusions (OR, 10.214; 95%CI: 2.191–47.623) were associated with the development of BPD. Conclusion: Clinical evidence has been provided for possibly significant risk factors associated with BPD in neonates born at ≤1500 g, which can provide useful information for further research to improve survival of VLBW infants and decrease the incidence of BPD.     

Cerebral palsy and multiple births.

AIM: To compare the birthweight specific prevalence of cerebral palsy in singleton and multiple births. METHODS: Registered births of babies with cerebral palsy born to mothers resident in the counties of Merseyside and Cheshire during the period 1982 to 1989 were ascertained. RESULTS: The crude prevalence of cerebral palsy was 2.3 per 1000 infant survivors in singletons, 12.6 in twins, and 44.8 in triplets. The prevalence of cerebral palsy rose with decreasing birthweight. The birthweight specific prevalence among those of low birthweight < 2500 g was not significantly different in singleton than in multiple births. Among infants weighing > or = 2500 g, there was a significantly higher risk in multiple than in singleton births. The higher crude cerebral palsy prevalence in multiple births is partly due to the lower birthweight distribution and partly due to the higher risk among normal birthweight infants. CONCLUSIONS: Multiple birth babies are at increased risk of cerebral palsy. There is also an increased risk of cerebral palsy within a twin pregnancy if the co-twin has died in utero.     

Comparison of morbidities in very low birthweight and normal birthweight infants during the first year of life in a developing country

Objective : To compare the morbidities in the very low birthweight (VLBW; < 1500 g) and normal birthweight (NBW; ± 2500 g) Malaysian infants during the first year of life.
Methodology : Prospective observational cohort study of consecutive surviving VLBW infants and randomly sampled NBW infants born in the Kuala Lumpur Maternity Hospital between 1 December 1989 and 31 December 1992. Infants were followed up regularly during the first year of life, after correction for prematurity.
Results : Compared with NBW infants ( n = 106), VLBW infants ( n = 127) had significantly higher risk of failure to thrive (odds ratio [OR] = 8.0, 95% confidence intervals [Cl]: 1.1 to 354.3), wheezing (OR = 3.7, 95% Cl: 1.6 to 9.3), rehospitalization (OR = 2.3, 95% Cl: 1.1 to 5.0), cerebral palsy (OR = 8.6, 95% Cl: 2.0 to 77.6), neurosensory hearing loss (OR = 12.0, 95% Cl: 1.7 to 513.6) and visual loss (7.9 vs 0%, P = 0.002). The mean mental developmental index (MDI) and mean psychomotor developmental index (PDI) at 1 year of age were significantly lower among VLBW infants (MDI 99 [SD = 28], PDI89 [SD = 25]) than NBW infants (MDI 106 [SD = 18], PDI 101 [SD = 18]) (95% Cl for difference between means being MDI: -14.1 to -1.7; and PDI: -17.6 to -6.0). Logistic regression analysis showed that among VLBW infants: (i) male sex, Malay ethnicity and bronchopulmonary dysplasia were significant risk factors associated with wheezing; (ii) longer duration of oxygen therapy during the neonatal period, seizures after the post-neonatal period and wheezing were significant risk factors associated with rehospitalization; and (iii) longer duration of oxygen therapy during the neonatal period was a significant risk factor associated with adverse neurodevelopmental outcome during the first year of life.
Conclusions : Compared with NBW infants, VLBW Malaysian infants had significantly higher risks of physical and neurodevelopmental morbidities.     

Effect of ethnicity on mortality of very low birthweight infants in Israel

BACKGROUND: Multiple demographic, genetic, and environmental factors differ between Muslim and Jewish infants in Israel. OBJECTIVE: To evaluate whether, after adjustment for perinatal factors associated with mortality, excess mortality occurs in very low birthweight (VLBW) Muslim compared with Jewish infants. DESIGN: The Israel National VLBW infant database includes data on 99% of all VLBW births in Israel. The study population comprised 5015 Jewish and 1549 Muslim VLBW infants of more than 23 weeks gestation, born between 1995 and 1999. The Mantel-Haenszel test was used for stratified analysis and logistic regression analysis to assess the effect of ethnic origin on mortality. RESULTS: The death rate was significantly higher among Muslim infants (22.7% v 17.2%; crude odds ratio 1.42; 95% confidence interval 1.24 to 1.63). Excess mortality in Muslims occurred mainly in the 32-33 week (8.0% v 2.8%) and >33 week (14.7% v 4.7%) gestational age groups, and in birthweight groups of 1000-1249 g (17.6% v 9.3%) and 1250-1500 g (9.1% v 3.6%). In VLBW infants without congenital malformations, there was a significantly higher risk of mortality among Muslim infants (odds ratio 1.28; 95% confidence interval 1.04 to 1.57) compared with Jewish infants, after adjustment for gestational age, birth weight, small for gestational age, prenatal care, prenatal steroid treatment, plurality, mode of delivery, and Apgar score. CONCLUSIONS: Excess mortality was present among Muslim VLBW infants without congenital malformations. Perinatal factors associated with increased risk of mortality were more prevalent in the Muslim VLBW population. The pattern of disparities suggests inadequate access to, or utilisation of, effective perinatal technology in the Muslim population in Israel.     

Improved outcome into the 1990s for infants weighing 500-999 g at birth

AIMS—To compare the survival and sensorineural disability rates in extremely low birthweight (ELBW) (500-999 g) infants born in 1991-2 with ELBW babies born in 1979-80 and 1985-7, and with normal birthweight infants born in the same time periods.METHODS—ELBW infants born in Victoria in 1991-2 were compared with regional cohorts of ELBW infants born in 1979-80 and 1985-7, and with contemporaneous normal birthweight (>2499 g) controls, and those of birthweight 500-749 g with those of birthweight 750-999 g.RESULTS—In 1979-80, 25.4% (89/351) ELBW live births survived to 2 years of age, increasing significantly to 37.9% (212/560) in 1985-7, and to 56.2% (241/429) in 1991-2. The rates of severe disability in survivors assessed were 12.4%, 6.6%, and 6.8% in the 1979-80, 1985-7, and 1991-2 ELBW cohorts, respectively. The rate of disability, overall, was significantly lower in the 1985-7 and 1991-2 ELBW cohorts compared with the 1979-80 ELBW cohort, but was significantly higher in 1991-2 ELBW infants than normal birthweight controls. Surviving children with birthweights <750 g had significantly higher rates of sensorineural disability compared with those of birthweight 750-999 g in 1979-80, but not in 1985-7 or 1991-2.CONCLUSIONS—Survival rates for ELBW babies in Victoria have progressively improved since the late 1970s. Sensorineural outcome for survivors born in 1985-7 has also improved compared with those born in 1979-80. However, there is no evidence that further reductions in adverse sensorineural outcomes into the 1990s, and these, as well as disabilities remain higher in ELBW than in normal birthweight babies.     

Epidemiology of cerebral palsy in England and Scotland, 1984-9

AIMS—To report on the epidemiology of cerebral palsy in England and Scotland, to provide information on the prevalence of cerebral palsy and the severity of the disability or any co-morbidity.METHODS—Cerebral palsy registers were compiled from multiple sources of ascertainment covering all of Scotland and the counties of Merseyside, Cheshire, Berkshire, Buckinghamshire, Northamptonshire and Oxfordshire in England. All cases of cerebral palsy born in 1984 to 1989, to mothers resident in the area, were included. Denominator number of live births and neonatal deaths for determining birthweight specific prevalence were obtained from birth and death registrations. Learning, manual, and ambulatory disabilities were graded for severity. Any co-existing sensory (hearing or visual) morbidity was also graded for severity.RESULTS—There were 789 411 live births in 1984-9, with 3651 neonatal deaths (neonatal mortality 4.6 per 1000 live births) and 1649cases of cerebral palsy—a cerebral palsy prevalence of 2.1 per 1000 neonatal survivors. The birthweight specific cerebral palsy prevalence ranged from 1.1 per 1000 neonatal survivors in infants weighing ?2500 g to 78.1 in infants weighing <1000 g. There was no significant time trend in prevalence of cerebral palsy in any of the birthweight groups, in contrast to the fall in neonatal mortality observed in all birthweight groups. Of the 1649 cases of cerebral palsy, 550 (33.4%) had severe ambulatory disability (no independent walking), 390 (23.7%) had severe manual disability (incapable of feeding or dressing unaided), 381 (23.1%) had severe learning disability (IQ <50), 146 (8.9%) had severe visual disability (vision <6/60 in the better eye) and 12 had severe hearing disability (>70 dB loss).CONCLUSIONS—Registers fill an important gap left by the lack of routine data on the prevalence of disability in children. The ability to record trends in the prevalence and the severity of the disability should inform those who have responsibility for providing services for children with disabilities.     

Handicaps and health problems in 2 year old children of birth weight 500 to 1500 g

Fifty-nine infants of birthweight 500 to 999 g born in 1977 to 1980 and 132 infants of birthweight 1000 to 1500 g born in 1977 to 1978 were reviewed at two years corrected age. For the whole cohort, cerebral palsy was found in 12.6%, bilateral deafness in 1%, blindness in 1% and severe developmental delay in 12%. There was no significant difference in these disabilities between the groups of larger and smaller infants; 37.7% of the cohort was readmitted to hospital on at least one occasion, 35.6% of children had wheezing episodes and/or lower respiratory tract infections which together accounted for 51% of hospitalizations. The infants of birthweight 500 to 999 g tended to require more frequent and prolonged hospitalizations. Dolicocephalic head shape, chest deformities, iatrogenic sequelae from intensive care, poor growth and cicatricial retrolental fibroplasia were significantly more frequent in children of birthweight 500 to 999 g. Parents reported that 39% of their children had 'colic', 31.6% had sleep disturbance and 25% had multiple behavioural problems. Low frustration tolerance, inability to wait, hypo- or hyperactivity and an inappropriate relationship with the mother as measured by the psychologist all occurred significantly more frequently in children of birthweight of less than 1000 g. This report confirms the belief that a comprehensive follow-up is required for very low birthweight (VLBW) children because significant health problems continue after primary hospitalization.     

Handicaps and health problems in 2 year old children of birth weight 500 to 1500 g

Fifty-nine infants of birthweight 500 to 999 g born in 1977 to 1980 and 132 infants of birthweight 1000 to 1500 g born in 1977 to 1978 were reviewed at two years corrected age. For the whole cohort, cerebral palsy was found in 12.6%, bilateral deafness in 1%, blindness in 1% and severe developmental delay in 12%. There was no significant difference in these disabilities between the groups of larger and smaller infants; 37.7% of the cohort was readmitted to hospital on at least one occasion, 35.6% of children had wheezing episodes and/or lower respiratory tract infections which together accounted for 51% of hospitalizations. The infants of birthweight 500 to 999 g tended to require more frequent and prolonged hospitalizations.
Dolicocephalic head shape, chest deformities, iatrogenic sequelae from intensive care, poor growth and cicatricial retrolental fibroplasia were significantly more frequent in children of birthweight 500 to 999 g. Parents reported that 39% of their children had 'colic', 31.6% had sleep disturbance and 25% had multiple behavioural problems. Low frustration tolerance, inability to wait, hypo- or hyperactivity and an inappropriate relationship with the mother as measured by the psychologist all occurred significantly more frequently in children of birthweight of less than 1000 g. This report confirms the belief that a comprehensive follow-up is required for very low birthweight (VLBW) children because significant health problems continue after primary hospitalization.     

Invasive fungal infection in very low birthweight infants: national prospective surveillance study

OBJECTIVE: To describe the epidemiology of invasive fungal infection in very low birthweight (VLBW: <1500 g) infants in the United Kingdom. DESIGN: National prospective surveillance study between February 2003 and February 2004 using the British Paediatric Surveillance Unit reporting system reconciled with cases identified through routine laboratory reporting to the Health Protection Agency (England, Wales, and Northern Ireland), the Scottish Centre for Infection and Environmental Health, and the UK Mycology Reference Laboratory. RESULTS: Ninety four confirmed cases of invasive fungal infection were identified during the surveillance period giving an incidence of estimated annual incidence of 10.0 (95% confidence interval (CI) 8.0 to 12.0) cases per 1000 VLBW live births. Eighty one (86%) of the infants were of extremely low birth weight (ELBW: <1000 g), incidence 21.1 (95% CI 16.5 to 25.7) per 1000 ELBW live births. Candida species, predominantly C albicans and C parapsilosis, were isolated in 93% of cases. Most organisms were isolated from the bloodstream and urinary tract. Death occurred in 41% of the infected infants before 37 weeks postconceptional age. CONCLUSIONS: The incidence of invasive fungal infection in VLBW and ELBW infants in the United Kingdom is lower than reported in previous studies from tertiary centres in North America and elsewhere. The associated late neonatal and post-neonatal death rates are substantially higher than expected in infants without invasive fungal infection. These data may inform decisions about the evaluation and use of antifungal infection control strategies.     

Very low birth weight preterm infants with early onset neonatal sepsis: the predominance of gram-negative infections continues in the National Institute of Child Health and Human Development Neonatal Research Network, 2002-2003

BACKGROUND: Early onset neonatal sepsis (EOS, occurring in the first 72 hours of life) remains an important cause of illness and death among very low birth weight (VLBW) preterm infants. We previously reported a change in the distribution of pathogens associated with EOS from predominantly gram-positive to primarily gram-negative organisms. OBJECTIVE: To compare rates of EOS and pathogens associated with infection among VLBW infants born at centers of the National Institute of Child Health and Human Development (NICHD) Neonatal Research Network during 3 time periods: 1991-1993; 1998-2000; and 2002-2003. STUDY DESIGN: Prospectively collected data from the NICHD Neonatal Research Network VLBW registry were retrospectively reviewed. Rates of blood culture confirmed EOS, selected maternal and infant variables and pathogens associated with infection were compared between 2002-2003 and 2 previously published cohorts. RESULTS: During the past 13 years, overall rates of EOS have remained stable (15-19 per 1000 live births of infants 401-1500 g). More than one-half of early infections in the 2002-2003 cohort were caused by gram-negative organisms (53%), with Escherichia coli the most common organism (41%). Rates of group B streptococcal infections remain low (1.8 per 1000 live births). Between 1991-1993 and 1998-2000, there was a significant increase in rates of E. coli infections; but in 2002-2003, there was no significant change (7.0 per 1000 live births). Infants with EOS continue to be at significantly increased risk for death compared with uninfected infants. CONCLUSION: EOS remains an uncommon but important cause of morbidity and mortality among VLBW infants. Gram-negative organisms continue to be the predominant pathogens associated with EOS.     

Outcome at 2 years for very low birthweight infants in a geographical population: risk factors, cost, and impact of congenital anomalies

AIM: To determine the type and rate of disability at 2 years of age in infants born in the geographically defined population of East Anglia with a birthweight less than 1500 g and to assess the risk factors for disability. STUDY DESIGN: A prospective cohort analysis from all eight neonatal units in East Anglia from 1993-1997 using a single database. METHODS: Local paediatricians assessed children at 2 years using the Health Status Questionnaire and data collection was centrally coordinated. RESULTS: Outcomes for 947 children, 99% of survivors, were available, 74 (7.8%) had severe disability and this was significantly associated with gestational age (p<0.0005), birthweight (p<0.0005) and sex (p=0.046). Major congenital abnormality contributed 27% of all severe disability. The overall cerebral palsy rate was 6.2%, nine children were blind and five had sensorineural hearing loss requiring aids. These children had a high level of use of community services with 19% of the cohort being referred to one or more community service. ELBW infants or those born <30 weeks gestation were 1.5 times and twice as likely to have moderate or severe disability and 2.3 and 5.4 times as likely to have cerebral palsy as those weighing 1000 to 1500 g or >30 weeks gestation. Boys were at higher risk of adverse outcome. CONCLUSIONS: The study was able to define the increased risk associated with being born at lower gestational age or lower birthweight and demonstrates successful ascertainment of outcomes for large local populations at a reasonable cost.     

Medical expenses of neonatal intensive care for very low birthweight infants

ABSTRACT. The in-hospital medical expenses for 90 very low birthweight (VLBW) infants weighing 1500 g or less at birth, whose parents had private health insurance, was reported. The median total and daily charges per survivor was $5,883 and $70 respectively. The median total and daily charges per non-survivor was $1,113 and $450 respectively. The medical expenses per VLBW survivor calculated for all 375 VLBW infants, admitted for neonatal intensive care over the 4 year period, was $6,813. This ranged from $10,000 per survivor for the 11 survivors in the 501 g-750 g birthweight group to $5,363 per survivor for the 145 survivors in the 1251 g-1500 g birthweight group. As these charges were probably a small proportion of the resource costs in providing a neonatal intensive care service, society at large was bearing most of the cost. Nevertheless, we believe that with the present decline in neonatal mortality and morbidity in VLBW infants, the outcome of neonatal intensive care justifies the cost.     

The changing epidemiology of cerebral palsy.

AIM: To determine the prevalence of cerebral palsy in a specific population. METHODS: Multiple sources of ascertainment were used to create and maintain a register of all cases of cerebral palsy born to mothers resident in the counties of Merseyside and Cheshire in the years 1966 to 1989. Denominator data of infant births and deaths from 1966 to 1981 were obtained from statutory notifications made to health authorities and, for the period 1982-89, from statutory birth and death registrations. Over 1500 cases formed the database for the study. RESULTS: The prevalence of cerebral palsy has increased among all the low birthweight groups with, most recently, an increase in infants weighing < 1000 g at birth. Low birthweight infants now comprise about 50% of all cases of cerebral palsy; in the early years of the study they comprised about 32% of all cases. The proportion of cerebral palsy by clinical type has changed among low birthweight babies, with relatively fewer cases with diplegia and a concomitant increase in the proportion with hemiplegia. An increase in the severity of functional disability, determined by the proportion of children with severe learning, manual, and ambulatory disabilities, was also found. CONCLUSIONS: The change in the epidemiology of cerebral palsy has implications for the aetiology of the condition, and for health, educational, and social service provision.     

Outcomes of very‐low‐birthweight infants at 3 years of age born in 2003–2004 in Japan

Background: The aim of this study was to describe and compare neurodevelopmental outcomes with birthweight (BW) groups at 250‐g intervals of very‐low‐birthweight (VLBW) infants at 3 years of age in a multicenter cohort in Japan. Methods: A total of 3104 VLBW infants born in 2003 and 2004 registered in a NICU‐network database were followed in the study. Neurodevelopmental impairment (NDI) was defined as any of the following impairments: cerebral palsy, unilateral or bilateral blindness, severe hearing impairment, or developmental delay; a developmental quotient (DQ) <70 measured using the Kyoto Scale of Psychological Development test or judged by physicians in infants without the test. Results: A total of 257 infants died and follow‐up data were obtained from 1826 infants. Of the 1826 infants, 155 (8.5%) had cerebral palsy, 25 (1.4%) had visual impairment, and 12 (0.7%) had hearing impairment. Of the 1197 infants in whom DQ was measured, 184 (15.4%) had DQ < 70. The proportion of NDI in the evaluated infants was 19.2% (n= 350), ranging from 11.9% (BW 1251–1500 g) to 42.0% (BW ≤ 500 g). Odds ratios (95%CI) of NDI or death against the group BW 1251–1500 g were 20.62 (13.29–31.97) in BW ≤ 500 g, 7.25 (5.45–9.64) in BW 501–750 g, 2.85 (2.12–3.82) in BW 751–1000 g and 1.18 (0.85–1.64) in BW 1001–1250 g. Conclusion: The increasing proportion of NDI or death, an indicator of adverse outcome, was associated with decrement in the BW of the groups. Although we have to consider a bias due to loss of follow‐up data, the incidence of NDI was similar to previous overseas cohort studies despite the higher survival proportion in our study.     

Trends in incidence of cranial ultrasound lesions and cerebral palsy in very low birthweight infants 1982-93.

AIM: To evaluate the effects of changing perinatal practice on outcome in terms of cranial ultrasound appearances and subsequent cerebral palsy rates in survivors. METHODS: A tertiary neonatal centre based prospective cohort study was undertaken of very low birthweight infants, in three 4 year periods: 1982-5, 1986-9, 1990-3. Rates of survival, parenchymal cerebral haemorrhage (PH), and leucomalacia on cerebral ultrasound scans, and cerebral palsy (CP) at the age of 3 years were compared. Antenatal steroid prophylaxis and postnatal surfactant use were also compared. RESULTS: VLBW infants (1722) were admitted over the 12 years, of whom 1268 (73.6%) were discharged home. Neonatal survival increased significantly over the three periods (69.2%, 72.9%, 79.7%; p < 0.0001). PH declined from 14.9% to 10.5% (p = 0.032) after 1990 as did CP rate (10.9% to 7.3%; p = 0.046). The use of antenatal steroids and postnatal surfactant greatly increased during this period. Steroid use was significantly associated with increased survival (OR 3.34, 2.31-4.79), decreased PH (OR 0.44, 0.28-0.71), and decreased risk of CP in survivors (OR 0.47, 0.27-0.81) after standardising for gestation, birthweight, sex, place and mode of delivery. Similar effects for surfactant did not remain significant after steroid use had been accounted for. CONCLUSION: Improved survival in VLBW infants since 1990 has been accompanied by a fall in PH and subsequent CP rates in survivors. This change is most likely to be due to the greater use of antenatal steroid prophylaxis.     

Results of intensive care for 375 very low birthweight infants

ABSTRACT. In the 4 years 1977 to 1980, 375 infants weighing 501–1500g were admitted to the neonatal unit of the Queen Victoria Medical Centre. Overall neonatal survival was 79%; 56% of infants weighing 501–1000g and 89% of infants weighing 1001–1500g survived. Four post neonatal deaths occurred in hospital. Perinatal factors associated with decreased survival were indicators of perinatal asphyxia, thus demonstrating the imortance of the prevention of this condition in the management of early preterm labour. The survival rate for infants born after Caesarean section was significantly higher than those born after vaginal delivery for the whole study group but not among the smallest infants weighing ≤ 1000g. The two most common causes of respiratory failure were hyaline membrane disease and recurrent apnoea of prematurity. Two hundred and forty-seven (68%) infants required assisted ventilation, of whom 116 (67%) survived. Although the majority of infants could be ventilated successfully with low peak airway and positive and expiratory pressures, the prevention of air leak and bronchopulmonary dysplasia remain a therapeutic challenge. As we now expect the majority of very low birthweight infants to survive, documentation of short and long term morbidities are essential in order to determine how much greater an improvement can be expected by the use of new innovations in perinatal care.     

The cost of improving the outcome for infants of birthweight 500-999 g in Victoria: THE VICTORIAN INFANT COLLABORATIVE STUDY GROUP

The aim of this study was to conduct an economic evaluation of neonatal intensive care for extremely low birthweight (ELBW) infants born in the state of Victoria. Two distinct eras (1979–80 and 1985–87) were compared. Follow-up data at 2 years of age were available for all 89 survivors from the 351 live births in 1979–80, and for 211 of 212 survivors from the 560 live births in 1985–87. The overall cost-effectiveness for ELBW infants during 1985–87 compared with 1979–80 was$104 990 ($A 1987) per additional survivor, or$5390 ($A 1987) per additional life year gained. Cost-effectiveness improved with increasing birthweight. If the quality of life of the survivors was considered, the economic outlook was more favourable. The cost per quality-adjusted life year gained was$5090 ($A 1987), approximately one-tenth of that obtained from the only previous full economic evaluation of neonatal intensive care. Although neonatal intensive care is expensive, it compares favourably with some other health care programmes, particularly as the outcome for ELBW infants continues to improve.     

Cerebral palsy in the surviving twin associated with infant death of the co-twin

BACKGROUND: Monozygotic twins are at greater risk of dying and of serious morbidity than dizygotic twins, and both are at greater risk than singletons. This is only partly explained by the higher proportion of low birthweight infants among twins. AIM: To compare, in same sex and different sex twins, birth weight specific neonatal death rates and cerebral palsy prevalence rates in the surviving twin when the co-twin has died in infancy. METHODS: Analysis of birth and death registration data for same sex and different sex twins for England and Wales 1993-1995 where both were live births. Death certificates of all liveborn twins who died were obtained from the Office for National Statistics. A questionnaire was sent to the general practitioners of all surviving co-twins to determine if the child had any disability. RESULTS: The neonatal death rate in same sex twins was 25.4 and in different sex twins 18.0 per 1000 live births (death rate difference 7.4; 95% confidence interval 4.7 to 10.1; p < 0.001). The higher neonatal death rate in same sex compared with different sex twins is attributable to the higher proportion of same sex twins with low birth weight. Prevalence of cerebral palsy in the low birthweight group (< 1000 g) was marginally higher in same sex (224 per 1000) than different sex (200 per 1000) twin survivors. In the birth weight group 1000-1999 g, same sex twin survivors were at a significantly higher risk of cerebral palsy than those of different sex: 167 v 21 per 1000; difference 145 (95% confidence interval 44 to 231; p < 0.01) per 1000 infant survivors. CONCLUSION: There are two components to the cause of cerebral palsy in twins. Immaturity per se predisposes to cerebral damage. Also, same sex twins may sustain cerebral damage that is in excess of that due to immaturity.