Why have we failed to reduce the frequency of cerebral palsy?

Comparison of single event vs multiple event soft tissue surgeries in the lower extremities with cerebral palsy

In children with spasticity of multiple muscle groups, the need for repeat surgical interventions increases with advancing age.

AIM

The present study aimed to investigate retrospectively whether there are any clinical and functional differences between single-event multilevel surgeries and multiple surgical events at a single level.

METHOD

The medical records of 109 patients with cerebral palsy (CP) were used. The patients, who met the inclusion and exclusion criteria, were assigned into following 4 groups based on the surgical procedures. The Gross Motor Function measure-88 (GMFCS) and Functional Independence Measure for Children (WeeFIM) were used for assessments.

RESULTS

When compared to groups, there was no significant difference. This study showed that both surgical techniques resulted in improvements in GMFCS and WeeFIM levels.

Treatable inborn errors of metabolism presenting as cerebral palsy mimics: systematic literature review

Background

Inborn errors of metabolism (IEMs) have been anecdotally reported in the literature as presenting with features of cerebral palsy (CP) or misdiagnosed as ‘atypical CP’. A significant proportion is amenable to treatment either directly targeting the underlying pathophysiology (often with improvement of symptoms) or with the potential to halt disease progression and prevent/minimize further damage.

Methods

We performed a systematic literature review to identify all reports of IEMs presenting with CP-like symptoms before 5 years of age, and selected those for which evidence for effective treatment exists.

Results

We identified 54 treatable IEMs reported to mimic CP, belonging to 13 different biochemical categories. A further 13 treatable IEMs were included, which can present with CP-like symptoms according to expert opinion, but for which no reports in the literature were identified. For 26 of these IEMs, a treatment is available that targets the primary underlying pathophysiology (e.g. neurotransmitter supplements), and for the remainder (n = 41) treatment exerts stabilizing/preventative effects (e.g. emergency regimen). The total number of treatments is 50, and evidence varies for the various treatments from Level 1b, c (n = 2); Level 2a, b, c (n = 16); Level 4 (n = 35); to Level 4–5 (n = 6); Level 5 (n = 8). Thirty-eight (57%) of the treatable IEMs mimicking CP can be identified by ready available metabolic screening tests in blood or urine, while the remaining IEMs require more specific and sometimes invasive tests.

Conclusions

Limited by the rare nature of IEMs and incomplete information in the literature, we conclude that (1) A surprisingly large number of IEMs can present with CP symptoms, as ‘CP mimics’, (2) although individually rare, a large proportion of these diseases are treatable such that neurological damage can either be reversed or prevented, (3) clinician awareness of treatable CP mimics is important for appropriate screening, diagnosis, and early intervention, and (4) systematic studies are required to elucidate the collective frequency of treatable IEMs in CP.

Electronic supplementary material

The online version of this article (doi:10.1186/s13023-014-0197-2) contains supplementary material, which is available to authorized users.

Changes in the clinical spectrum of cerebral palsy over two decades in North India--an analysis of 1212 cases

BACKGROUND

Clinical spectrum of cerebral palsy (CP) is different in developing and developed countries. We evaluated the clinical profile, etiological factors and co-morbidities of children with CP in North India, and compared with our previous study.

METHODS

1212 children with CP registered in last 10 years in our rehabilitation center were compared with our previous study of 1000 children from same center.

RESULTS

Spastic quadriplegia is the commonest type of CP (51.5%) although lesser than previous decade (61%). Birth asphyxia remains the main (51.98%) etiological factor as earlier (45.3%). CP due to CNS infections decreased from 63.5% to 57.4%, due to bilirubin-encephalopathy remained same (∼30%). Speech problems (83.7%), microcephaly (64.27%), seizures (44.5%) and intellectual disability (38.61%) are common co-morbidities. Common neuroimaging findings include hypoxic-ischemic changes and periventricular leucomalacia.

CONCLUSION

The spectrum of CP is evolving in the developing countries with an increase in diplegic and a decrease in quadriplegic CP.

Outcome of extreme prematurity: a prospective comparison of 2 regional cohorts born 20 years apart

OBJECTIVE

To determine changes that have occurred over the past 20 years in perinatal characteristics, neonatal treatments, morbidities, and early neurodevelopmental outcomes of infants born at < or =30 weeks' gestation.

METHODS

This was a prospective regional study including all live-born infants < or =30 weeks' gestation born between July 1985 and June 1986 (cohort 1) and July 2005 and June 2006 (cohort 2). Sociodemographically matched term controls were recruited for each cohort. Perinatal characteristics, mortality rates, and survival with and without impairments at 24 months' corrected age were compared.

RESULTS

There was a 35% increase in the number of live-born preterm births (138 in cohort 1 and 187 in cohort 2) despite a >10% decline in total births in the region (P < .001). Assisted fertility (rarely available for mothers in cohort 1) was responsible for 20% of pregnancies in cohort 2. Survival to hospital discharge increased over 20 years from 82% to 93% (P = .002), primarily because of higher survival for infants born at <27 weeks' gestation (63% vs 88%; P = .004). Changes in management in cohort 2 included the use of surfactant (62% of infants) and increased use of postnatal steroids (39% vs 9%; P < .001), that were associated with a shorter median duration of mechanical ventilation (13 vs 21 days; P < .001); however, the incidence of bronchopulmonary dysplasia was higher in cohort 2 (56% vs 35%; P < .001). There was a significant decrease in incidence of severe ultrasound abnormalities from 17% in cohort 1 to 7% in cohort 2 (P = .008). At 24 months of age, 7% of cohort 1 and 5% of cohort 2 had an abnormal neurologic exam. Bayley cognitive scores were improved in cohort 2 (significantly closer to the mean of their controls). As a result, survival without severe neurodevelopmental impairment increased from 62% in cohort 1 to 81% in cohort 2 (P < .001).

CONCLUSION

Over 20 years, there has been a significant increase in live births at < or =30 weeks' gestational age, with a greater percentage of these neonates surviving without severe neurodevelopmental impairment at 24 months.

[The upper limb of children with cerebral palsy: surgical aspects]

Cerebral palsy has a complex and multifactorial etiology. The management of the upper limb aims to improve function, hygiene and cosmesis in many patients. Surgical treatment need a good and repeated clinical examination before. The functional surgery has a lot of procedures on the elbow, the wrist, the fingers and the thumb. These procedures include the release or lengthening of spastic muscles, tendon transfers and joint stabilizations. The surgeon must know the indications and contraindications of functional surgery.

A survey of regional guidelines for intrapartum electronic fetal monitoring in women at low obstetric risk

AIM

to determine whether intrapartum fetal monitoring guidelines used by midwives in one region of England for women at low risk of obstetric complications were evidence-based.

OBJECTIVE

to assess the quality of such guidelines using an appraisal tool.

DESIGN AND SETTING

an appraisal of guidelines gained via a postal survey of all National Health Service Trusts supplying maternity services in one region in the north of England, conducted over a six-week period (June-July 2001).

PARTICIPANTS

28 Trusts were eligible to participate; 32 guidelines were returned from 24 Trusts.

DATA ANALYSIS

two reviewers from a multi-disciplinary panel appraised each guideline, producing two sets of data that were analysed independently of each other. Each was treated as a separate case (n=64 cases). Inter-reviewer agreement was summarised using descriptive categories.

FINDINGS

the highest possible overall quality score was 54, and the lowest 18. Whilst no guideline scored 54, five of the 64 cases scored 18. The mean overall quality score was 26.8. In 36 of the 64 cases, both reviewers rated guidelines as 'definitely not' recommended for practice. Guidelines were scored against specific aspects of evidence-based practice. Forty-one of the 64 cases received the lowest possible quality score (='1') for use of systematic reviews of the literature on electronic fetal monitoring. In 47 cases, guidelines were scored '1' for the quality of evidence-based clinical recommendations. The quality of information on client monitoring preferences was considered low in over half the 64 cases (n=35). There were no instances where the number of cases receiving 'highest possible quality' scores was greater than those receiving 'lowest possible quality' ratings.

CONCLUSIONS AND IMPLICATIONS FOR PRACTICE

a small number of guidelines were assessed as high quality, but the majority were poorly appraised by the reviewer group in most areas. This has implications for the delivery of evidence-based midwifery care since those midwives practising according to the guidelines surveyed would not have been supported in implementing research into practice.

Neonatal cerebral white matter injury in preterm infants is associated with culture positive infections and only rarely with metabolic acidosis

OBJECTIVE

Neonatal cerebral white matter injury represents a major precursor for neurological impairment and cerebral palsy. Our objective was to identify risk factors associated with its development.

STUDY DESIGN

This retrospective case-control study of all births between 23 and 34 weeks gestation at a single university hospital between May 1994 and September 2001 identified 150 cases with white matter injury characterized by periventricular leukomalacia or ventricular dilatation from white matter atrophy that were chromosomally normal and did not have other congenital anomalies. Cases were matched to controls without brain injury by the next delivery within 7 days of their gestational age.

RESULTS

There were small differences between controls and cases in gestational age (27.5 +/- 2.7, 27.4 +/- 2.6 weeks, P = .01) and birth weight (1053 +/- 402, 966 +/- 285 g, P = .002) that were statistically but not clinically significant. There was no difference in the percentage of controls and cases delivered by cesarean (45%, 49%, P = .64). There were no differences between controls and cases in umbilical arterial pH (7.27 +/- 0.11, 7.25 +/- 0.15, P = .19), base excess (-2.1 +/- 2.7, -3.0 +/- 4.1 mmol/L, P = .28), pH less than 7.0 (2/122 [2%], 3/107 [3%], P = 1.0), or base excess less than -12 mmol/L (4/121 [3%], 6/106 [6%], P = .75). The cases had a significant increase in positive blood (19%, 29%, P = .036), cerebrospinal fluid (6%, 17%, P = .002), and tracheal (9%, 22%, P = .003) cultures during the neonatal period. Conditional logistic regression showed a significant association among multiple gestations ( P = .02), intraventricular hemorrhage ( P < .001), and positive tracheal cultures ( P = .02) with cerebral white matter injury.

CONCLUSION

Culture-positive infection was associated with an increased risk of cerebral white matter injury in preterm neonates. Intrapartum hypoxia-ischemia as manifested by metabolic acidosis was rarely associated with white matter injury and was not different from the incidence in premature neonates without injury.

Antenatal risk factors for cerebral palsy

Two of every 1000 live-born children develop cerebral palsy (CP). The aetiology of CP is often unclear and because CP is a symptom complex rather than a disease, clinically defined at 4-5 years of age, it is not surprising that there are considerable problems associated with epidemiological studies of its aetiology. The only reason for the CP concept is that it emanates from an insult to a growing, developing brain and a dynamic clinical picture from static pathology. Evidence suggests that 70-80% of CP cases are due to prenatal factors and that birth asphyxia plays a relatively minor role (<10%). Some antenatal risk factors are repeatedly observed to be related to CP: low gestational age, male gender, multiple gestation, intrauterine viral infections and maternal thyroid abnormalities. Recently, intrauterine infection/inflammation with a maternal response (consisting of chorioamnionitis) and a fetal inflammatory response (consisting of funicitis or elevated interleukin-6 in fetal plasma) has been found to be related to white matter injury and CP. Some risk factors are associated with CP at all gestational ages whereas others mostly affect term or preterm infants, e.g. intrauterine growth restriction seems to be a risk factor in term infants. There also seems to be an association between autoimmune and coagulation disorders and CP.

Cerebral palsy registries

Cerebral palsy (CP) registers appear to be appropriate tools for answering questions regarding the prevalence and characteristics of this common childhood disability. Registers are population databases issuing from multiple sources, relying on a clear definition and inclusion and exclusion criteria of CP, and requiring a mix of skills with the collaboration of obstetricians, pediatricians, and epidemiologists. In Europe alone there are 18 different CP registers or population data collections on CP, and collaborative research efforts exist through a European network. Data collection on CP has also been done in Australia (register), the United States (surveys), and Canada (register). Beside monitoring trends, other public health contributions of CP registers might be to reduce the frequency of CP and to improve the quality of life of children with CP. CP registers are useful to clinicians by enabling them to identify subgroups of children requiring specific etiologic investigations, and also to provide more accurate information to the parents of children with CP.

Etiology of cerebral palsy

Cerebral palsy has a complex and multifactorial etiology. Approximately 5%-10% of cases can be ascribed to perinatal hypoxia, but the vast majority of cases are caused by the interplay of several risk factors and antenatal, perinatal, and neonatal events. The strongest risk factors include prematurity and low birth weight. The prevalence of cerebral palsy has remained constant despite improvements in obstetric and neonatal care. For a long time, the only causal factors explored to account for risk for cerebral palsy were complications of labor and delivery. As other periods have been investigated, new associations have come to light. The current understanding of contributors to the risk for cerebral palsy is still incomplete. Multiple causes may interact by way of excitotoxic, oxidative, or other converging pathophysiologic pathways. A single factor, unless present to an overwhelming degree, often may be insufficient to produce cerebral damage, whereas two or three interacting pathogenic assaults may overwhelm natural defenses and produce irreversible brain injury. The low prevalence of cerebral palsy makes the formal testing of preventative strategies difficult. There is a need for such strategies to be carefully assessed in well designed, multicenter, randomized, controlled trials before becoming part of clinical practice, however, so that the balance between harm and benefit is known in advance.

Disabilities and trends over time in a French county, 1980-91

AIM

To describe trends over time and types of disability for children born in a French county from 1980 to 1991.

METHODS

Data were collected from medical records of a morbidity register; disabled children with at least one severe deficiency have been included. Prevalence rates are given per 1000 resident children, over four three-year periods.

RESULTS

Overall, 7.73 per 1000 children (that is, 1360 children), had a severe childhood disability, and the prevalence rate had increased significantly since 1980. This increase was mainly owing to an increase in cerebral palsy and psychiatric disorder prevalence rates.

CONCLUSION

Future research aimed to explain these trends over time can be based on such data. The present knowledge is useful for planning purposes.

Cerebral palsy in very preterm infants: new epidemiological insights

The focus of this review is on new insights from recent epidemiological research on cerebral palsy in preterm infants. These include: 1) a better understanding of issues related to diagnosis and classification; 2) new information about the brain abnormalities underlying cerebral palsy in preterm infants; and 3) a better understanding of biological mechanisms that may underlie previously described epidemiological associations. Ongoing efforts to improve the diagnosis and classification of cerebral palsy have been enhanced by findings from serial examinations of cohorts of very preterm infants. Cranial ultrasonography through the anterior fontanelle of very preterm infants has provided information about grossly evident brain damage, found in about one-half of preterm infants who develop cerebral palsy. Insights into the pathophysiologic basis for certain epidemiologic associations have come from studies of experimental brain damage in animals and clinical studies of neurologic disorders in adults. Much of the current epidemiological research into the causes of cerebral palsy in preterm infants has focused on two potential mechanisms of brain damage. One mechanism involves insufficient cerebral perfusion; the other, cytokine-mediated damage, potentially triggered by events such as maternal infection (e.g., intrauterine or periodontal infection), neonatal infection (e.g., sepsis and necrotizing enterocolitis), and neonatal oxygen- or ventilator-induced lung injury. In addition to the preterm infant's increased exposure to such damaging factors, the high frequency of cerebral palsy in these infants might be due, in part, to insufficient levels of developmentally regulated protective substances, such as thyroid hormone and glucocorticoids. Models of causation currently are being investigated using recently developed methods for quantifying, with small quantities of blood, biomolecules that are suspected to either promote or protect against brain damage in the neonate. Clinical investigations now under way can be expected to identify strategies to be tested in clinical trials that could lower the risk of cerebral palsy in very preterm infants.

Hypocapnia and other ventilation-related risk factors for cerebral palsy in low birth weight infants

Ventilatory management patterns in very low birth weight newborns, particularly iatrogenic hypocapnia, have occasionally been implicated in perinatal brain damage. However, such relationships have not been explored in large representative populations. To examine the risk of disabling cerebral palsy in mechanically ventilated very low birth weight infants in relation to hypocapnia and other ventilation-related variables, we conducted a population-based prospective cohort study of 1105 newborns with birth weights of 500-2000 g born in New Jersey from mid-1984 through 1987, among whom 777 of 902 survivors (86%) had at least one neurodevelopmental assessment at age 2 y or older. Six hundred fifty-seven of 777 assessed survivors (85%), of whom 400 had been mechanically ventilated, had blood gases obtained during the neonatal period. Hypocapnia was defined as the highest quintile of cumulative exposure to arterial PCO(2) levels <35 mm Hg during the neonatal period. Disabling cerebral palsy was diagnosed in six of 257 unventilated newborns (2.3%), 30 of 320 ventilated newborns without hypocapnia (9.4%), and 22 of 80 ventilated newborns with hypocapnia (27.5%). Two additional ventilatory risk factors for disabling cerebral palsy were found-hyperoxia and prolonged duration of ventilation. In a multivariate analysis, each of the three ventilatory variables independently contributed a 2- to 3-fold increase in risk of disabling cerebral palsy. These risks were additive. Although duration of mechanical ventilation in very low birth weight newborns likely represents severity of illness, both hypocapnia and hyperoxia are largely controlled by ventilatory practice. Avoidance of arterial PCO(2) levels <35 mm Hg and arterial PO(2) levels >60 mm Hg in mechanically ventilated very low birth weight infants would seem prudent.

[What protection for handicapped child and his family today and tomorrow? The Precariousness Commission of the French Society of Pediatrics]

The recent decision of a large insurance company to put an end to the contracts of insurance subscribed by thousands of French parents for their disabled children, has brought to light the precariousness of the disabled children in our society. The available assistance for the disabled children in the French social welfare is described. Although significant this national assistance remains insufficient in order to avoid the precariousness of the disabled children and their families. An additional effort of solidarity of both the community and the insurance companies is therefore necessary.

Can neurological injury be timed?

Our knowledge about the cause of cerebral palsy continues to expand and prenatal events are thought to play an important role. This article reviews laboratory tests, imaging studies and pathologic findings that have been used to identify the timing of neurological injury. Limitations exist for all modalities, however, imaging studies, electroencephalograms and pathologic examination provide the most useful information. Improvements in our ability to time neurological injury will better direct our efforts to prevent cerebral palsy.

Antecedents of cerebral palsy in very low-birth weight infants

Research from the last two decades provides directions for efforts to prevent CP in VLBW infants. The pathogenesis of CP seems to involve factors operating both during pregnancy and in the neonatal period. The most important prenatal factor appears to be intrauterine infection. Perinatal infection and other risk factors, such as the death of a co-twin, placental abruption, and cerebral ischemia, could trigger a cytokine cascade resulting in damage to the developing brain. The low frequency of intrauterine infection in mothers with preeclampsia might explain the apparent protective effect of this disorder. If the brain damage attributed to intrauterine infection and other risk factors involves cytokines as intermediates, then blockade of the proinflammatory cascade or promotion of endogenous inhibitors might prevent CP. Other potentially preventive strategies include corticosteroids given to mothers (but not those given to neonates) and thyroid hormone.

The evaluation of an expert system for the analysis of umbilical cord blood

An assessment of neonatal outcome may be obtained from analysis of blood in the umbilical cord of an infant immediately after delivery. This can provide information on the health of the new-born infant, guide requirements for neonatal care, but there are problems with the technique. Samples frequently contain errors in one or more of the important parameters, preventing accurate interpretation and many clinical staff lack the expert knowledge required to interpret error-free results. The development and implementation of an expert system to overcome these difficulties has previously been described. This expert system validates the raw data, provides an interpretation of the results for clinicians and archives all the results, including the quality control and calibration data, for permanent storage. Issues regarding the clinical evaluation of this system are now detailed further, along with some clinical results illustrating the potential of such a system.

Prevalence of cerebral palsy in Alberta

BACKGROUND

In spite of scattered reports to the contrary, concern is continually expressed that the frequency of cerebral palsy has not decreased with modern perinatal/neonatal care. Overall, epidemiological information on cerebral palsy is scant. The generally accepted prevalence is 2 to 2.5 per thousand school-age children.

METHODS

A population-based record linkage study of a presently living cohort of 96,359 children born from April, 1985 through March, 1988 and followed over an eight-year tracking period captured the diagnostic codes for all fee-for-service physician claims, all hospital separations and individual birth data from the Department of Vital Statistics of the Government of Alberta. The ICD-9 code "343" was used to identify subjects. The childhood prevalence and frequency by birthweight-specific sub-groups of cerebral palsy after age three years (congenital, 229 [92.3%]; probable acquired 19 [7.7%]) were identified giving an overall prevalence of 2.57 per 1000. Seventy percent were diagnosed before their third birthday. Cohort prevalence of cerebral palsy for low birthweight children (< 2500 grams) was 17.7, very low birthweight (< 1500 grams), 78.5; and extremely low birthweight (< 1000 grams), 98.4. Low birthweight children made up just over one-third of cases in this study.

CONCLUSIONS

Cerebral palsy continues to affect a significant number of children suggesting the prevalence of cerebral palsy has not decreased. The proportion of affected children with low birthweight in this study is less than that reported in the literature.

Risk factors for cerebral palsy

Cerebral palsy is a major cause of crippling in children, but it's etiology is poorly understood. This case control study was done to assess some of the identified risk factors for cerebral palsy, 125 cerebral palsy cases selected from hospital clinic and 125 age and sex matched neighbourhood controls, all aged less than 5 years and residing in Delhi (India) were studied. Information regarding antenatal, natal and postnatal period was collected by mother's interview, and wherever available, from hospital records with the study subjects. Most common type of cerebral palsy was spastic (88%). Quadriplegia was the commonest topographical subtype (86.4%). Birth asphyxia was found to be present in only 25.6% of cases. The commonest risk factor amongst cases was low birth weight (28.8%). The multivariate odds ratios (confidence limits) for the risk factors found to be significantly associated with cerebral palsy were 36.1 (7.76-160) for birth asphyxia, 13.8 (4.95-38.3) for low birth weight, 37.4 (4.47-313) for neonatal convulsion, 23 (4.7-112) for neonatal jaundice, 14.4 (3.69-56.4) for neonatal infection, 24.9 (2.78-223) for instrument assisted delivery and 15.4 (1.57-152) for antepartum hemorrhage. Precipitate labour, caesarean section, twins, toxemia, breech delivery and head injury were not found to be significantly associated with cerebral palsy. Thus birth asphyxia, low birth weight, neonatal convulsions, neonatal jaundice, neonatal infection, instrument assisted delivery and antepartum hemorrhage are significant risk factors for cerebral palsy.

Prevalence and impact of chronic childhood conditions in Auckland, New Zealand

OBJECTIVE

To establish the prevalence of specific chronic conditions of childhood in the Auckland area and to quantify resource use by these children.

METHODOLOGY

Estimates were made from available registry data and published data sources of the population of children with selected chronic conditions resident in the Auckland Area Health Board area. Resource use data were extracted for admissions to Auckland public hospitals and from providers of community based technology services.

RESULTS

The largest community prevalence groups are those with asthma, intellectual handicap, congenital heart disease and epilepsy. Children aged 0-14 with chronic conditions accounted for at least 14,340 hospital days stay in Auckland in 1992 at an estimated minimum cost of $7.9 million. Over 200 children are dependent on technological aids at home.

CONCLUSIONS

There are sparse data on the numbers and needs of children with chronic conditions in the population. A non-categorical approach which crosses disease entities may be the best method of meeting common needs.

Prevalence and aetiology of neurological impairment in extremely low birthweight infants

OBJECTIVE

To determine the prevalence and perinatal predictors of cerebral palsy, intellectual impairment, visual impairment and deafness in a cohort of extremely low birthweight (ELBW) infants at two years of age.

METHODOLOGY

The study population comprised 199 of the 224 (89%) ELBW infants managed at the Mater's Mothers Hospital, Brisbane, between July 1977 and February 1990 and who survived to two years. The prevalence of cerebral palsy, intellectual impairment, blindness and deafness was measured by clinical,psychometric and audiological assessment and the association with 24 risk factors examined.

RESULTS

Cerebral palsy occurred in 20 children (10%). Risk of cerebral palsy was associated with ventricular dilatation, intraventricular haemorrhage, necrotizing enterocolitis and multiple birth, though only ventricular dilatation (OR 4.41; 95% CI 1.32-14.8) remained significant in the adjusted analysis. Intellectual impairment occurred in 20 children (10%) and was independently associated with ventricular dilatation (OR 15.0; 95% CI 2.2-102.8), ventilation F(i)(2) > 80% (OR 3.4; 95% CI 1.01-11.5), vaginal delivery (OR 3.5; 95% Cl 1.09-11.4) and male sex (OR 6.1; 95% Cl 1.67-22.3). No perinatal predictor was statistically associated with risk of deafness. Retinopathy of prematurity (OR 36.9; 95% Cl 2.8-495.5) was associated with risk of later visual impairment.

CONCLUSIONS

Intellectual impairment was associated with a broad range of perinatal variables. Cerebral palsy was associated with fewer variables, all of which were also associated with intellectual impairment. Neurologic injury was associated with male sex and multiple birth, which are not biological insults themselves, but may be markers of susceptibility to injury.

Geburtsasphyxie als Ursache kindlicher Hirnschäden?

The prevalence of cerebral palsy (CP) has increased over the last 15 years in most countries. This is explained by an improved survival of very low birth weight prematures. In term infants birth asphyxia is of minor significance as a cause for CP. In only 10% of all CP cases following delivery at term, birth asphyxia must be discussed as a possible cause. In premature deliveries events during the perinatal period are of greater significance for the later development of a CP. Only severe forms of oxygen deficit, leading to tissue damage in the brain and other organs with clinical symptoms during the first days of life, are of significance for the long term prognosis. Even in the presence of severe birth asphyxia the causal relationship with a psychomotor handicap is not proven, since brain damage may have developed during pregnancy before the onset of labour and may be the cause of birth asphyxia. Brain damage and birth asphyxia may be the result of a common pathology of pregnancy.

Predictors of neonatal encephalopathy in full-term infants

OBJECTIVE

Preliminary investigation of the contribution of adverse antepartum and intrapartum factors to neonatal encephalopathy in singleton neonates born full term.

DESIGN

Matched case-control study based on incidence density sampling of controls.

SETTING

Two major teaching hospitals (one paediatric and one obstetric) and three peripheral maternity hospitals in Perth, Western Australia (population 1.2 million).

SUBJECTS

89 cases, all the full term singleton neonates born during an eight month period in 1992 who fulfilled one or more of six criteria during the first week of life (seizures, abnormal conscious state, persistent hypertonia or hypotonia, and feeding or respiratory difficulties of central origin). One full term control infant without neonatal encephalopathy was matched to each case by sex, hospital of delivery, time of day and day of the week of birth, and maternal health insurance status.

MAIN OUTCOME MEASURES

Odds ratio estimates of relative risk of neonatal encephalopathy associated with antepartum and intrapartum factors.

RESULTS

Estimated incidence of moderate or severe encephalopathy in first week of life was 3.75 per 1000 full term live births. Thirteen cases and no controls had evidence suggestive of important intrapartum hypoxia, and in only five of these cases was the neurological condition at birth attributed to events during the intrapartum period. Univariate conditional logistic regression analysis identified significant differences between cases and controls for maternal vaginal bleeding in pregnancy, maternal thyroxine treatment, congenital abnormalities, induction of labour, interval from membrane rupture to delivery, maternal pyrexia in labour, augmentation of labour, abnormal intrapartum cardiotocograms, and meconium in labour. Family history of convulsions also approached significance.

CONCLUSIONS

Our preliminary results suggest that intrapartum hypoxia, according to currently used criteria, was not the cause of neonatal encephalopathy in most cases in this population. Our findings suggest that many aetiologies of neonatal encephalopathy originate in the antepartum period.

Model to identify potentially preventable cerebral palsy of intrapartum origin

A six stage model was applied to a geographically defined population of 210 singleton children born at term who had a diagnosis of cerebral palsy at 5 years of age. Thirty five children were identified as those most likely to have cerebral palsy of intrapartum origin; in 26 of these there was evidence of suboptimal care. It is suggested that this simple model should be tested on populations of children with cerebral palsy and the underlying principles used when considering the likely cause of cerebral palsy in individual children.

Technology seduction: lost opportunities in child health?

This report examines the extent to which illness-based individual care and expensive, often unevaluated, technologies in paediatrics have seduced practitioners away from more cost-effective, population-based child health activities and examples of new and unevaluated technologies in perinatology and paediatrics are given. The way in which these technologies are introduced and taken up, by 'creeping incrementalism', is described and a plea is made to implement only those aspects of paediatric care that have been demonstrated to be effective. This would result in only appropriate technologies being used, avoid harm being done to children and ensure that money is available for other effective population-based activities that improve child health.

Antenatal antecedents of moderate and severe cerebral palsy

Aetiological relationships between cerebral palsy, preterm birth, small-for-gestational-age (SGA) birth and selected feto-maternal factors were investigated in a case-control study of all moderate and severe cerebral palsy cases born in Western Australia between 1980 and 1986 (n = 215). Cases were individually matched to three controls of the same gender and plurality born in the same year. Two of the controls were matched to the index cases for gestational age, one of which was also matched for birthweight. Pre-eclampsia and urinary tract infections were not significantly associated with cerebral palsy. The significant association of antepartum haemorrhage with cerebral palsy was accounted for by its associations with preterm birth. Congenital malformations and non-cerebral palsy neurological disorder were significantly associated with cerebral palsy; these associations were only partially accounted for by adjusting for preterm birth and small-for-gestational-age birth. This study shows that some of the risk of cerebral palsy associated with the antenatal antecedents of some common feto-maternal factors is mediated through preterm birth, confirming the importance of interrelationships between antenatal antecedents in the aetiology of some cerebral palsy. Perinatal and post-neonatal causes now account for only around 20% of all cerebral palsy. Future reductions in cerebral palsy incidence may therefore depend on acquiring greater knowledge of inter-relationships between antenatal antecedents.

Family patterns of gestational age at delivery and growth in utero in moderate and severe cerebral palsy

The relation of familial factors to the aetiology of cerebral palsy was assessed in a case-control study of all moderate and severe cases born in Western Australia between 1980 and 1986. The data did not suggest recurrence of cerebral palsy, congenital malformations or reproductive loss in cerebral palsy families. Preterm and small-for-gestational-age birth recurred within both case and control families. Cases and controls did not differ significantly from their siblings in measures of intra-uterine growth, but (with the exception of controls unmatched for both birthweight and gestational age) were born significantly earlier than their siblings. A family history of preterm or small-for-gestational-age birth was found to affect the risk of cerebral palsy by influencing the risk of preterm birth or growth retardation in the index pregnancy.

A population database for maternal and child health research in Western Australia using record linkage

This paper describes a linked total population database established in Western Australia for monitoring and evaluating maternal and child health and for conducting epidemiological studies. Good vital statistics data including all Western Australian hospitalisations and excellent birth defects and cerebral palsy registers have ensured that complete data are available. Examples of studies which have been conducted using the database are given.

Cerebral palsy and neonatal encephalopathy

A retrospective cohort study was carried out to test the hypothesis that children born at term with cerebral palsy with signs of neurological dysfunction preceded by depression at birth (termed neonatal encephalopathy) differ from those without such signs in the frequency of antenatal and perinatal factors, and in the severity and characteristics of their impairment and disability. The study was carried out in the area covered by Oxford Regional Health Authority. Antenatal, intrapartum, neonatal factors, and the later clinical status of the two groups of children were used as the main outcome measures. Although most maternal and antenatal characteristics were similar in the two groups, the mothers of children with a history of neonatal encephalopathy were more likely to be primigravidae (odds ratio (OR) 2.0; 95% confidence interval (CI) 1.0 to 4.3) and to have a pregnancy of greater than 41 weeks' gestation (OR 3.5; 95% CI 1.0 to 12.1). Intrapartum complications were more frequent in the neonatal encephalopathy group: meconium staining of the amniotic fluid (OR 3.5; 95% CI 1.5 to 7.8), an ominous first stage cardiotocograph (OR 10.2; 95% CI 2.9 to 36.4), with a longer median duration of abnormality (200 v 48 minutes). At 5 years of age those with neonatal encephalopathy were more likely to have developed spastic quadriplegia (OR 4.8; 95% CI 2.2 to 10.5), to have visual impairment (OR 3.0; 95% CI 1.0 to 8.6), and to be non-walking (OR 4.0; 95% CI 1.8 to 8.8) than those without neonatal encephalopathy. Children with cerebral palsy who were born at term and have neonatal encephalopathy are more likely to have had signs of intrapartum asphyxia and are more likely to have a more severe form of cerebral palsy than those without a history of neonatal encephalopathy. Although this group represents only one in 10 of all cases of cerebral palsy, some of these may be obstetrically preventable.

The aetiology of cerebral palsy

I have attempted to give an overview of the latest thoughts on the aetiology of the cerebral palsies. These motor disabilities are of continuing interest and their prevalence is rising, particularly in low birth weight preterm singletons and multiple births. The likely multiplicity of causes demands intelligent investigation probably in collaborative population data bases. Ultrasound and other scans may provide better data on both site and timing of neonatal brain damage. However these are more likely to have been done on cerebral palsied children who were preterm than on those born at term. There are currently no clear preventive messages except those relating to postnatal cerebral palsy or encouraging strategies to reverse the increases in multiple births. The challenges now are to obtain better data on the antenatal factors and on causal sequences which may be important. The Little Foundation is seeking to encourage such collaborative studies. Other suggestions from our workshop [14] included attempting to follow up those infants who have been participants in large randomised controlled trials (such as those evaluating surfactant) to the age when they can be confidently diagnosed as having cerebral palsy. If antenatal data have been collected on them they may form the basis for a cohort analysis relating risk to cerebral palsy occurrence, as well as to answer questions about whether the intervention influenced cerebral palsy occurrence.

Heterogeneity of neurological syndromes in survivors of grade 3 and 4 periventricular haemorrhage

To evaluate the topographical neurological distribution, patterns of abnormal tone and related functional neuromotor impairment after grade 3 and grade 4 intraventricular/periventricular haemorrhage (IPVH), 33 children with previous grade 3 or 4 IPVH of mean gestational age 30.9 weeks (range 25-40 weeks) and mean birth weight 1743 g (range 866-3600 g) were examined neurologically at 4.7 years (range 0.75-10.8 years). Neurological signs were absent in 10/33 cases which were equally distributed between the grade 3 and grade 4 IPVH groups. The largest single topographical neurological distribution was hemiparesis in 8/23, followed jointly by diplegia (cerebral paraplegia) in 6/23 and triplegia in 6/23 cases and finally quadriplegia in 3/23 cases. Grade 4 IPVH tended to result in asymmetrical syndromes, accounting for 7/8 cases of hemiparesis and 5/6 cases of triplegia, whereas all 3/3 cases of quadriplegia followed grade 3 IPVH. The 6/23 cases of diplegia were shared between the grade 3 and grade 4 IPVH groups. Tone was normal in 7/8 of the hemiparetic subjects. Dystonia was the commonest tone abnormality, affecting 8/23 children with neurological disturbance, followed by ataxia/hypotonia in 4/23 and mixed dystonia/hypotonia in 3/23. Only 1/23 cases had signs of spasticity. Spasticity is rare following severe IPVH. Diplegic children had a better functional neuromotor grade than hemiparetic children, who in turn did better than triplegic children. Ataxia hypotonia resulted in better functional outcome than dystronia, which in turn was more favourable than mixed tone patterns. Cranial imaging by ultrasound (US) or computed tomographic (CT) scanning proved an unreliable prognostic indicator except in the case of hemiparesis, for which US scans correctly predicted the affected side in 5/7 cases. The neurological syndromes following severe IPVH differ from the classical encephalopathy of prematurity, and this should lead to a re-appraisal of the trends in the prevalence of cerebral palsy. Caution should be exercised in the interpretation of cranial imaging with regard to pessimistic prognoses in the presence of changes or undue optimism in their absence.

Aetiological pathways to spastic cerebral palsy

An aetiological pathway is a sequence of interdependent events culminating in disease. Recognition of such pathways can be clinically useful if it suggests more effective methods of disease prevention. Kernicterus arising from feto-maternal Rhesus incompatibility and resulting in choreoathetosis comprises an aetiological pathway to cerebral palsy. The failure to recognise sufficient causes or to intervene effectively when a sufficient cause is suspected in the majority of cerebral palsy cases suggests that there may be other aetiological pathways. Evidence for other pathways was sought in the data from the Western Australian case-control study of 183 children with spastic cerebral palsy. Two or more factors likely to be of aetiological significance were recognised for nearly one-third of cases. As anticipated, the numbers with any specific combination of factors were small, pointing to the need for collaborative studies to obtain larger numbers to confirm their aetiological significance. The implications for the true proportion of cases with multifactorial aetiology and the problems inherent in such an investigation are discussed.

The relationship between psychosocial factors and developmental outcome for very low and extremely low birthweight infants: a review

Over the last quarter century, the improved survival rate of very low birthweight infants has sharpened questions about their residual disabilities. Longitudinal studies have devoted attention to the cognitive and neurodevelopmental outcome of these infants, but much less is known about their long-term social and emotional development. Psychiatrists consulting to neonatal intensive care units and assessing these infants in their families, will be assisted by a better understanding of the developmental and psychological outcomes of such infants. This paper reviews the state of knowledge in both of these areas. It argues the paramount importance of psychosocial factors to the infants' developmental outcome, and the importance of longitudinal research in further clarifying the predictive value of these factors. In a subsequent paper, we consider the efficacy of interventions with this group.

Improvement in outcome for very low birthweight children: apparent or real?

OBJECTIVE

To determine whether improvement in the survival rate of infants with a birthweight of less than 1501 g was accompanied by an increase in the rate of neurological impairment or disability among the survivors.

DESIGN, SETTING AND PATIENTS

Two cohorts of consecutive very low birthweight infants (birthweight less than 1501 g) in one tertiary perinatal centre were followed prospectively to eight years of age; for both cohorts, comparison groups of children of birthweight more than 1501 g were randomly selected from hospital births.

INTERVENTIONS

The first cohort was born before the introduction of assisted ventilation (1966-1970), the second after assisted ventilation was well established (1980-1982).

MAIN OUTCOME MEASURES

Comparisons between cohorts, at eight years of age, of the survival rates and the rates of severe sensorineural impairments and disabilities.

RESULTS

The survival rate for very low birthweight infants to eight years of age almost doubled between these cohorts, from 37.1% to 67.8% (odds ratio [OR], 3.4; 95% confidence interval [CI], 2.5-4.7; chi 2 = 57.6; P much less than 0.0001). The biggest gain was the increase in non-disabled survivors at eight years of age, from 52.6% in the first cohort to 80.8% in the second cohort (OR, 3.5; 95% CI, 2.2-5.7; chi 2 = 26.7; P less than 0.0001). Furthermore, the rate of severe disabilities in survivors fell substantially, from 13.6% to 4.1% (OR, 0.31; 95% CI, 0.14-0.69; chi 2 = 8.3; P less than 0.01). Of specific impairments, the rate of severe sensorineural deafness fell substantially (3.2% to 0%: OR, 0.14, 95% CI, 0.02-0.81; chi 2 = 4.8; P less than 0.05), as did the rate of severe intellectual impairment (13.0% to 2.7%: OR, 0.25; 95% CI, 0.11-0.57; chi 2 = 10.7; P less than 0.002). Only the rate of cerebral palsy increased, but not significantly (2.6% to 6.8%; OR, 2.6; 95% CI, 0.89-7.6; chi 2 = 3.0).

CONCLUSIONS

It has been possible to improve the survival rate of very low birthweight infants over time without increasing the number of severely disabled survivors. Whether the long-term outcome for these infants is continuing to improve with more recent advances in perinatal care remains to be determined.

Trends in perinatal mortality and cerebral palsy in Western Australia, 1967 to 1985

OBJECTIVE

To analyse the trends in stillbirths, neonatal deaths, and cerebral palsy in all infants born in Western Australia from 1967 to 1985. To relate these trends to changes in perinatal care, particularly in relation to avoidance of intrapartum asphyxia in term infants and the increased survival of low birthweight infants.

DESIGN

Descriptive epidemiological study calculating population rates for perinatal deaths and cerebral palsy according to year of birth and birth weight.

SETTING

Western Australia.

SUBJECTS

All infants born after 20 weeks' gestation or weighing at least 400 g (live and stillborn).

MAIN OUTCOME MEASURES

Stillbirths, neonatal deaths (from perinatal death certificates), and cerebral palsy (from a population based register).

RESULTS

Overall stillbirth rates fell from 12.1/1000 total births in 1967-70 to 8.1 in 1983-5. Early neonatal mortality fell from 13.0/1000 live births to 4.4 over the same period whereas total cerebral palsy rates remained at around 2-2.5/1000 live births. Death rates fell in all birth weight categories, particularly in low birthweight infants between 1975 and 1985, the period when birthweight data were available. In contrast, cerebral palsy rates in infants under 1500 g rose significantly over this period (from 12.1 in 1968 to 64.9 in 1985). The rise was seen in all spastic categories, including severely and multiply handicapped children.

CONCLUSIONS

Large increases in the use of interventions aimed at reducing birth asphyxia and handicaps had not (by 1985) resulted in lower rates of cerebral palsy. This suggests that birth asphyxia is not a major cause. The increased survival of low birthweight infants has resulted in more cerebral palsy in this group, due either to postnatal complications of immaturity or prenatal damage to the fetal brain. These findings have implications for planning perinatal care and for litigation for putative obstetric malpractice in cerebral palsy cases.

Survival and cerebral palsy in low birthweight infants: implications for perinatal care

Whilst only about a third of all cerebral palsy occurs in children who had been of low birthweight, recent increases in the survival of low and very low birthweight infants have coincided with significant increases in the numbers of cerebral palsy children amongst them. This paper analyses data from the Western Australian Cerebral Palsy Register and from the Maternal and Child Health Research Data Base for stillbirths, neonatal deaths and survivors to address the issues of increased survival, cerebral palsy and timing of brain damage. The analysis is inconclusive but suggestive that both antenatal and postnatal complications are important in the increases in cerebral palsy in low birthweight infants. The good news is that this means that a certain proportion of postnatally damaged low birthweight survivors could possibly be prevented by better neonatal care. The bad news is that the remaining proportion have probably received their damage well before delivery and the possibilities for prevention are still remote. Further studies of low birthweight infants with cerebral palsy are urgently required. They should include antenatal factors, investigating the various aetiological pathways to preterm birth, randomised controlled trials of neonatal interventions and searching for better neonatal predictors of brain damage.