Neurodevelopmental outcome in very-low-birth-weight infants with or without periventricular haemorrhage and/or leucomalacia

Impact of peri-intraventricular haemorrhage and periventricular leukomalacia in the neurodevelopment of preterms: A systematic review and meta-analysis

Context

Whether all degrees of periventricular leukomalacia (PVL) and peri-intraventricular haemorrhage (PIVH) have a negative impact on neurodevelopment.

Objective

To determine the impact of PVL and PIVH in the incidence of cerebral palsy, sensorineural impairment and development scores in preterm neonates. Registered in PROSPERO (CRD42017073113).

Data sources

PubMed, Embase, SciELO, LILACS, and Cochrane databases.

Study selection

Prospective cohort studies evaluating neurodevelopment in children born preterm which performed brain imaging in the neonatal period.

Data extraction

Two independent researchers extracted data using a predesigned data extraction sheet.

Statistical methods

A random-effects model was used, with Mantel-Haenszel approach and a Sidik-Jonkman method for the estimation of variances, combined with Hartung-Knapp-Sidik-Jonkman correction. Heterogeneity was assessed through the I² statistic and sensitivity analysis were performed when possible. No funnel plots were generated but publication bias was discussed as a possible limitation.

Results

Our analysis concluded premature children with any degree of PIVH are at increased risk for cerebral palsy (CP) when compared to children with no PIVH (3.4, 95% CI 1.60–7.22; 9 studies), a finding that persisted on subgroup analysis for studies with mean birth weight of less than 1000 grams. Similarly, PVL was associated with CP, both in its cystic (19.12, 95% CI 4.57–79.90; 2 studies) and non-cystic form (9.27, 95% CI 5.93–14.50; 2 studies). We also found children with cystic PVL may be at risk for visual and hearing impairment compared to normal children, but evidence is weak.

Limitations

Major limitations were the lack of data for PVL in general, especially for the outcome of neurodevelopment, the high heterogeneity among methods used to assess neurodevelopment and the small number of studies, which led to meta-analysis with high heterogeneity and wide confidence intervals.

Conclusions

There was no evidence supporting the hypothesis that PIVH causes impairment in neuropsychomotor development in our meta-analysis, but review of newer studies show an increased risk for lower intelligence scores in children with severe lesions, both PIVH and PVL. There is evidence to support the hypothesis that children with any degree of PIVH, especially those born below 1000 grams and those with severe haemorrhage, are at increased risk of developing CP, as well as children with PVL, both cystic and non-cystic.

Thyroxine for transient hypothyroxinemia and cerebral palsy in extremely preterm infants

BACKGROUND

The relationship of thyroxine supplementation for transient hypothyroxinemia of prematurity to the incidence of cerebral palsy (CP) in infants <28 weeks of gestation is unclear.

METHODS

The incidence of CP at a corrected age of 18 months was compared between infants born in a 3-year period in which routine measurement of free T4 (FT4) in the blood was not performed (first period, n= 54), and those born in a later 3-year period in which FT4 was measured (second period, n= 60; mainly at 7 days old), and in which l-thyroxine 5-10 µg/kg per day (mean, 9 µg/kg/day) was administered for FT4 levels <0.8 ng/dL. Incidence of CP at 3 years of age was also compared between the same groups.

RESULTS

Background clinical factors between the two groups were comparable except for prenatal steroid administration, which was reduced in the second period. Incidence of CP at a corrected age of 18 months was significantly lower in the second period (3.3%) than in the first period (16.6%). Incidence of CP at 3 years of age was also significantly lower in the second period. Multiple logistic regression analysis using factors except thyroxine supplementation, for the total of 114 infants from both groups, found no perinatal factors related to the development of CP at a corrected age of 18 months.

CONCLUSIONS

Thyroxine supplementation for transient hypothyroxinemia of prematurity may reduce the incidence of CP in extremely preterm infants. Large-scale randomized controlled trials are essential to determine the effects of thyroxine supplementation in reducing the incidence of CP among extremely preterm infants.

Deciding to resuscitate extremely premature babies: how do parents and neonatologists engage in the decision?

Parents at risk of delivering a baby at the threshold of viability are faced with a critical decision. When a child is born between 23 and 25 weeks of gestation, parents are asked to decide whether or not to resuscitate their child. In essence, they are faced with a choice between life and death. We conducted a qualitative study to explore how parents and neonatologists engage in decision-making in a context of imminent and unplanned delivery at the threshold of viability. Twelve parents and attending neonatologists in a specialized tertiary care centre in Montreal, Canada were separately interviewed immediately following neonatal consultation. Results highlight how neonatologists and parents engage in decision making from different standpoints: while neonatologists focus on the management of the unborn baby, parents have yet to fully conceptualize their infant as a distinct entity since they are in a process of grieving their pregnancy and their parenthood project. Moreover, in their attempt to ensure an informed decision, neonatologists adopt either of two models through provision of the most up-to-date and objective information available: "remaining as neutral as possible to allow parents to make their own decision", or, "formulating a proposal to which parents can choose or not to assent". Overall, if the provided information fits parents' expectations, they tend to feel confident with their decision. However, if it does not take their experience into account, their decision is experienced as a solitary process. Parents express the need to receive more than just factual information from neonatologists. They also require support and engagement from caregivers to manage the uncertainty. This brings into question the traditional concept of neutral informed consent and suggests the necessity of a shared decision-making model to ensure that the decision to resuscitate extremely premature babies, at the limits of viability, becomes a truly ethical task.

The effect of maturation and sedation on amplitude-integrated electroencephalogram of the preterm neonate: results of a prospective study

BACKGROUND AND AIM

Amplitude-integrated electroencephalogram (aEEG) is becoming more common in NICUs for monitoring infants after perinatal asphyxia. We used aEEGs for preterm infants, and analysed the influence of sedation and maturation on their aEEG, focusing on continuous activity.

METHODS

Weekly or biweekly aEEGs were performed in preterm infants and evaluated by visual analysis.

RESULTS

We analysed 92 aEEGs of 56 preterm infants (gestational age (GA) 24 + 6 to 34 + 0 wk, median 30 + 0 wk). In their first week of life, children with higher GA had a higher percentage of continuous activity: with a GA < or = 28 + 0 wk it was 8.1%, 33.5% with a GA from 28 + 1 to 30 + 0 wk (p=0.02), 85.9% with a GA from 30 + 1 to 32 + 0 wk (p=0.005), and 89.1% with a GA from 32 + 1 to 34 + 0 wk. Continuous activity increased with growing postnatal age. With a GA < or = 28 + 0 wk, it rose from 8.1% (first week) to 55.3% (second week) and reached 96.8% (week 6/7) (p=0.017). With GA from 28 + 1 to 30 + 0 wk, continuous activity was 33.5% (first week) and 86.6% (second week) (p=0.03).

CONCLUSION

The aEEG of preterm infants appears to be a good tool for monitoring cerebral activity. Continuous activity seems to indicate maturation in the neonatal brain. Further investigations of aEEGs in preterm infants should be performed.

Hemorrhagic-ischemic cerebral injury in the preterm infant: current concepts

PV-IVH and adjacent white matter injury remains a significant problem in the premature infant. The potential mechanisms contributing to injury are complex and involve factors related to blood flow and its regulation, as well as cellular mediators including cytokines, free radical formation, and excitotoxin release. Although a reduction in the occurrence of severe IVH can be achieved with indomethacin, it does translate into long-term neurodevelopmental benefit. This reinforces the concept of a more diffuse injury to brain in sick premature infants than is apparent from the appearance of current neuroimaging techniques.

Bedside functional imaging of the premature infant brain during passive motor activation

BACKGROUND

Changes in regional brain blood flow and hemoglobin oxygen saturation occur in the human cortex in response to neural activation. Traditional functional radiologic methods cannot provide continuous, portable measurements. Imaging methods, which use near-infrared light allow for non-invasive measurements by taking advantage of the fact that hemoglobin is a strong absorber at these wavelengths.

AIMS

To test the feasibility of a new optical functional imaging system in premature infants, and to obtain preliminary brain imaging of passive motor activation in this population.

METHODS

A new optical imaging system, the Diffuse Optical Tomography System (DOTS), was used to provide real-time, bedside assessments. Custom-made soft flexible fiberoptic probes were placed on two extremely ill, mechanically ventilated 24 week premature infants, and three healthier 32 week premature infants. Passive motor stimulation protocols were used during imaging.

RESULTS

Specific movement of the arm resulted in reproducible focal, contralateral changes in cerebral absorption. The data suggest an overall increase in blood volume to the imaged area, as well as an increase in deoxyhemoglobin concentration. These findings in premature infants differ from those expected in adults.

CONCLUSIONS

In the intensive care setting, continuous non-invasive optical functional imaging could be critically important and, with further study, may provide a bedside monitoring tool for prospectively identifying patients at high risk for brain injury.

Ultrasound diagnosis and neurodevelopmental outcome of localised and extensive cystic periventricular leucomalacia

AIMS

To compare the ultrasound (US) evolution and neurodevelopmental outcome of infants with localised (grade II) and extensive (grade III) cystic periventricular leucomalacia (c-PVL).

METHODS

Over a nine year period, c-PVL was diagnosed in 96/3451 (2.8%) infants in two hospital cohorts. Eighteen were excluded from the study. Thirty nine infants with grade II PVL were compared with 39 infants with grade III PVL.

RESULTS

The two populations were comparable for gestational age and birth weight. In infants with grade II PVL, cysts were noted to develop more often after the first month of life (53%) in contrast with grade III PVL (22%) (odds ratio (OR) 3.81 (95% confidence interval (CI) 1.19 to 12.63)). Cysts were also more often unilateral in grade II (54%) than in grade III PVL (0%) (OR indefinite; RR 3.17 (95% CI 2.16 to 4.64)). At 40 weeks postmenstrual age (PMA), cysts were no longer seen on US in 13/38 infants with grade II PVL, with ventriculomegaly being the only visible sequel in nine cases. In grade III PVL, cysts were still present in 25 of the 27 surviving infants. Nine infants with grade II PVL were free of motor sequelae at follow up compared with one infant with grade III PVL (OR 8.07 (95% CI 0.92 to 181.66)). Twenty two out of 29 children with grade II PVL who developed cerebral palsy achieved independent walking compared with 3/26 with grade III PVL (OR 75 (95% CI 11.4 to 662)).

CONCLUSIONS

In the cohort studied, 50% of the infants with c-PVL had a more localised form (grade II). In grade II PVL, the cysts developed beyond the first month of life in more than half of the cases and were often no longer visible, on US, at 40 weeks PMA. In order not to miss this diagnosis, sequential US should also be performed beyond the first month of life. Mild ventriculomegaly noted at term can sometimes be due to grade II c-PVL. Cerebral palsy was slightly less common and tended to be less severe in infants with grade II PVL than in those with grade III PVL.

Risk factors for cerebral palsy in very low-birthweight infants in the 1980s and 1990s

One-hundred twenty-nine very low-birthweight infants were treated in Newborn and Infant Care Department of Children's Memorial Health Institute between 1985 and 1994; 89 were taken to prospective neurodevelopmental care. The newborns were divided into two groups. Group I had 38 preterm infants born from 1985 to 1989 and followed up at 7 to 11 years of age. Group II had 51 very low-birthweight infants treated from 1990 to 1994 and followed up at 2 to 5 years of age. Complicated, multiple pregnancy, normal delivery, and extremely low birthweight were significantly more frequent in group II. Very low-birthweight infants were frequently born by cesarean section in severe asphyxia. Only four (7.8%) newborns received surfactant therapy. From 1990 to 1994, respiratory distress syndrome III and IV, and a longer respiratotherapy period were significantly more frequent. From 1985 to 1994, the frequency of sepsis, periventricular leukomalacia, and normal ultrasonography was constant. Intraventricular hemorrhage I, II, and IV were frequently present in the 1990s, and intraventricular hemorrhage III was frequent in the 1980s. Cerebral palsy was diagnosed in 11 (28.9%) children in group I and 18 (35.2%) in group II (not statistically different). Multiple and complicated pregnancy, cesarean section, severe asphyxia, and respiratory distress syndrome did not increase the risk of cerebral palsy in very low-birthweight infants. Periventricular leukomalacia has a more predictive value for cerebral palsy in these infants than did intraventricular hemorrhage.

A critical review of cranial ultrasounds: is there a closer association between intraventricular blood, white matter abnormalities or cysts, and cerebral palsy?

In an attempt to determine cranial ultrasonographic features of preterm infants with intraventricular hemorrhage (IVH) and/or periventricular white matter abnormalities (PVWMA) that could serve as more specific predictors of cerebral palsy (CP), we reviewed the cranial sonograms of 34 infants with IVH and/or PVWMA. Fourteen of the 34 infants studied (41%) developed CP. One of five infants with grade III IVH alone developed CP. Eleven infants with PVWMA did not develop cysts and only two (18%) developed CP (p = 0.04). Of the 18 infants who went on to develop cysts, four had a small, discrete solitary cyst and 14 had large cystic areas. Three of the four with small cysts were neurologically normal, whereas only three of the 14 with large cysts were neurologically normal (p = 0.04). Preterm infants with grade III IVH in the absence of any parenchymal lesion had a more favorable neurologic outcome than those with IVH and concomitant PVWMA. Infants with PVWMA in the presence or absence of IVH had much poorer neurologic prognoses. In infants with PVWM abnormalities, both the presence and extent of cystic lesions, though not their location, are the strongest predictors of long-term neurologic outcome.

Periventricular leukomalacia: relation to gestational age and axonal injury

Eighty-five infants ranging from 22 to 41 weeks gestation were diagnosed as having periventricular leukomalacia (PVL) using traditional neuropathologic methods. The lesions were also studied by immunocytochemistry for beta-amyloid precursor protein (beta-APP), a glycoprotein that has been observed in PVL. Using this technique, the distribution of white matter tissue necrosis was defined as focal, widespread, and diffuse. The type of PVL correlated with the gestational age at birth. The youngest infants tended to demonstrate widespread necrosis, and the oldest infants exhibited more focal necrosis. beta-APP immunopositivity was present in the axons around the foci of white matter necrosis in 76% of the patients and in the neurons of the adjacent cortex in 66% of the patients. In age-matched control patients, there was no beta-APP reactivity in the cerebral white matter or the cortex. In most patients the distribution of beta-APP-positive axons proved to be a useful marker for demonstrating the type of PVL; however, the relationship of beta-APP to the pathogenesis of PVL requires further study.

White matter injury in the preterm infant: an important determination of abnormal neurodevelopment outcome

Periventricular white matter injury, specifically cystic periventricular leukomalacia (PVL) and ipsilateral hemorrhage into white matter associated with periventricular-intraventricular hemorrhage (PV-IVH), contribute significantly to neonatal mortality and long-term neurodevelopmental deficits in the premature infant. The first lesion PVL occurs in approximately 3-4% of infants of birth weight (BW) < 1500 grams. It manifests either as a focal or diffuse lesion within white matter. Although the pathogenesis of PVL is complex and likely multifactorial, principle contributors include vascular factors which markedly increase the risk for ischemia during periods of systemic hypotension and the intrinsic vulnerability of the oligodendrocyte to neurotoxic factors such as free radicals or cytokines. Clinical associations with PVL include a history of chorioamnionitis, prolonged rupture of membranes, asphyxia, sepsis, hypocarbia, etc. The vast majority of infants exhibit long-term neurodevelopmental deficits that affect motor, cognitive and visual function. The second lesion, the ipsilateral hemorrhage into white matter lesion associated with PV-IVH, occurs in approximately 10-15% of infants of BW < 1000 grams. The white matter injury appears to be a venous infarction with hemorrhage occurring as a secondary phenomenon. Prevention of this lesion has to include prevention of the associated PV-IVH. In this regard, the antenatal administration of glucocorticoids has been associated with a significant reduction in the sonographic incidence of severe IVH and the associated white matter involvement. The postnatal administration of indomethacin to high risk infants appears to hold the most promise at the current time in preventing this lesion. The neurodevelopmental outcome with extensive white matter injury is universally poor, affecting long-term motor and cognitive deficits; the long-term outcome is more favorable with lesser involvement. A clearer understanding of pathogenesis of both conditions is essential so as to provide targeted preventative strategies.

Brain injury in the premature infant: overview of clinical aspects, neuropathology, and pathogenesis

Brain injury in the premature infant is an extremely important problem, in part because of the large absolute number of infants affected yearly. The two principal brain lesions that underlie the neurological manifestations subsequently observed in premature infants are periventricular hemorrhagic infarction and periventricular leukomalacia. The emphases of this article are the neurology, neuropathology, and pathogenesis of these two lesions. Recent work suggests that the ultimate goal, prevention of the lesions, is potentially achievable. Periventricular hemorrhagic infarction may be preventable by prevention of germinal matrix/intraventricular hemorrhage, and periventricular leukomalacia, by detection of impaired cerebrovascular autoregulation, prevention of impaired cerebral blood flow, and interruption of the cascade to oligodendroglial cell death by such agents as free-radical scavengers.

Approaching the management of the neonatal intensive care unit graduate through history and physical assessment

NICU graduates, often ex-premature infants, offer unusual challenges to the primary care provider. History and physical assessment require an organized approach with meticulous attention to detail. These infants are at high risk for multiple problems including growth delays, nutrition and feeding problems, pulmonary sequelae, neurological sequelae and developmental delays, vision and hearing disturbances, as well as abnormalities in parent-infant bonding. This article emphasizes particular aspects of the history and physical examination that signify pathophysiology and sequelae common to the NICU graduate.

Brain injury in the premature infant--from pathogenesis to prevention

Brain injury in the premature infant is an extremely important problem, in part because of the large absolute number of infants affected yearly. The two principal brain lesions that underlie the neurological manifestations subsequently observed in premature infants are periventricular hemorrhagic infarction and periventricular leukomalacia. The emphases of this article are the neurology, neuropathology and pathogenesis of these two lesions. Recent work suggests that the ultimate goal, prevention of the lesions, is potentially achievable. Periventricular hemorrhagic infarction may be preventable by prevention of germinal matrix-intraventricular hemorrhage, and periventricular leukomalacia, by detection of impaired cerebrovascular autoregulation, prevention of impaired cerebral blood flow and interruption of the cascade to oligodendroglial cell death by such agents as free radical scavengers.

Neurodevelopmental outcome in very low birth weight infants at 24 months and 5 to 7 years of age: changing diagnosis

We describe the long-term development of 53 very low birth weight premature infants. The children were divided into 2 groups on the basis of ultrasound scan, and classified as: group I, patients with normal ultrasound scan or with uncomplicated hemorrhage; and group II, patients with complicated hemorrhage or only parenchymal lesions. Minor and major sequelae detected at 2 years of age were compared with those observed at 5 to 7 years. Our study confirms that most severely handicapped children are identified by age 2 years. Minor sequelae are more evident at 5 to 7 years and subjects with good outcome, as expressed by a McCarthy General Cognitive Index score > 80, present a discordant cognitive profile with verbal scores higher than performance scores. Therefore, we emphasize the importance of follow-up of very low birth weight premature infants until school age and stress that neonatal ultrasound scan diagnosis of parenchymal damage represents an important diagnostic tool in terms of both short- and long-term neurodevelopmental outcome.

Characteristic neuropathology of leukomalacia in extremely low birth weight infants

Extremely low birth weight (ELBW) infants with periventricular leukomalacia (PVL) were examined by neuropathological and immunohistochemical methods. Thirteen ELBW infants of 85 infants with PVL, born at 23 to 27 weeks of gestation, showed a widespread type of distribution of PVL from the deep to intermediate white matter. Immunohistochemistry demonstrated glial fibrillary acidic protein (GFAP)-positive astrocytes to be increased in the deep white matter, often spreading to the intermediate white matter, in all cases of PVL. Tumor necrosis factor-alpha (TNF-alpha)-positive cells were found in the deep to intermediate white matter in 69% of PVL cases and appeared earlier, from 23 weeks of gestation, than in controls. beta-Amyloid precursor protein (beta APP)-positive axons were found around PVL in the deep to intermediate white matter in 85% of the cases. In age-matched control ELBW infants, GFAP-, TNF-alpha-, or beta APP-positive cells were never found. Therefore, in ELBW infants, widespread axonal damage and glial activation with cytokine production occur in the progression in characteristic PVL lesions.

Perinatal risk factors and neuromotor behaviour during the neonatal period

Preterm birth is associated with an increased risk for neurological handicaps. The purpose of the present study has been: to investigate the influence of perinatal risk factors on early neuromotor development during the neonatal period; to specify the neuromotor parameters particularly sensitive to perinatal complications; and to analyse whether the infant's age at test influences the results. Beside examination of passive/active muscle tone and automatic movements (22 parameters) was performed at 36 (101 infants) and 40 (153 infants) gestational weeks. Low birthweight and long treatment on a ventilator had a negative influence on the neuromotor behaviour at 36 weeks' gestation and white matter disturbances strongly affected the neuromotor parameters at 40 weeks. The development of rooting, sucking, swallowing and arm recoil after long-lasting ventilator treatment was affected by several neonatal risk factors. The development of passive muscle tone and several parameters measuring active muscle tone demonstrated individual consistency between tests, i.e. an infant's rank at 36 weeks' gestation was unchanged 4 weeks later, and some other parameters were not as consistent. The present study shows that several perinatal risk factors influence neuromotor behaviour already during the neonatal period. In addition, the present study provides data on the neuromotor behaviour during the neonatal period that will be related to later neurodevelopmental examinations in order to evaluate the prognostic value of testing neuromotor development.

Diagnosis of intracranial lesions in very-low-birthweight infants by ultrasound: incidence and association with potential risk factors

This study was designed to determine the frequencies of germinal matrix and ventricular haemorrhages as well as lesions in the white matter diagnosed by ultrasonography. In subsequent studies the effects of perinatal brain lesions on the cognitive and motor development of preterm children will be presented. Lesions of the white matter are probably more damaging than intraventricular and subependymal bleeds. Therefore, a modified classification of the lesions was used, clearly separating bleeds from white matter pathology. The study includes 291 infants with a body weight of < or = 1500 g consecutively admitted to the neonatal intensive-case unit at Karolinska Hospital from 1988 to 1993. Fifty-four (18.9%) died before 6 months. Two hundred and sixty-three infants were examined using ultrasound. Pathology due to bleeding was classified into three grades (B1-3) similar to Papile's first three grades. Pathology in periventricular white matter was classified into four groups (W1-4): W1 = subtle and We = distinctive white matter echodensities; W3 = cyst formation; W4 = large, intense echodensity. Forty-nine patients had abnormalities in the periventricular white matter (15 W1, 12 W2, 11 W3 and 11 W4) and 58 had subependymal (B1 = 29) or ventricular bleeding without (B2 = 13) or with dilatation (B3 = 16). Ventilator treatment was significantly associated with both B and W lesions. Low gestational age, low birthweight, small for gestational age, pre-eclampsia and caesarean section were significantly associated with B lesions whereas asphyxia, surfactant treatment, male patient sex and outborn were associate with W lesions; b 1-3 and W 1-4 lesions were thus partly associated with different potential risk factors. The pre- and perinatal potential risk factors could only partly explain the variance in the frequency of B and W lesions, indicating that there are yet unidentified risk factors for intracranial ultrasonographic pathology.

Cerebral circulation assessed by transcephalic electrical impedance during the first day of life--a potential predictor of outcome?

Pulsatile changes in intracranial blood volume (transcephalic electrical impedance, delta Z), arterial blood pressure (aBP) and respiration were studied during the first day after birth in 42 neonates with a birth weight of 1040-3850 g and gestational age of 26-36 weeks. The neurological outcome was assessed at 1 year of age to study the predictive ability of delta Z. delta Z, ECG, respirogram and direct aBP were recorded at 8-h intervals. Outcome was adverse in seven infants of whom two died from severe peri-intraventricular haemorrhage. PCO2 was higher (6.2 kPa) in the infants with adverse outcome than in those infants with favourable outcome (5.0 kPa) (P = 0.004). Blood glucose (4.5 vs. 3.3 mmol/l, P = 0.030) and first day administration of fluid (80 vs. 63 ml/kg/day, P = 0.003) behaved, respectively. Of the infants receiving dopamine therapy, 60% had adverse outcome while only 11% of those not receiving dopamine had adverse outcome (P = 0.016). Of the infants with high diastolic blood pressure levels, 32% had adverse outcome, while none with low diastolic blood pressure levels had adverse outcome (P = 0.031). Spectral analysis was used to examine signal variabilities in the frequency domain. During the first 24 h of life, the variabilities of aBP and respiration were equal in all the infants. The high-frequency delta Z signal variability (1.50-4.00 Hz, heart rate level) was found to be lower in the infants with adverse outcome (330 units) than in the infants with favourable outcome (1280 units, P = 0.017). The low delta Z variability allowed us to assume that there is a decrease of pulsatile cerebral blood flow (CBF) in the infants with adverse outcome. We speculate that this may result from the 'no reflow phenomenon', increased tissue pressure due to ischaemia and/or PIVH, the 'brain sparing effect' or constriction of main cerebral arteries due to increased pressure support or metabolic factors (PCO2, glucose). We believe that transcephalic impedance provides a potential cot-side method for monitoring cerebral circulation in the neonatal period with an ability to predict outcome.

Severity of abruptio placentae and neurodevelopmental outcome in low birth weight infants

The short term neonatal morbidity and 2-year neurodevelopmental outcome were evaluated in 40 low birthweight (< 2500 g) liveborn infants delivered after abruptio placentae and in 80 control infants of similar gestational age. Apgar scores at 1' and 5' were lower in infants born to mothers with severe abruption. The prevalence of intraventricular hemorrhage (Grades I-IV) was 17.5% (7/40) in the cases and 5% (4/80) in the controls (P = 0.035). Cystic periventricular leukomalacia was diagnosed in two cases (5%) and in none of the controls (P = 0.1). At 2-year follow-up, among surviving infants, cerebral palsy (spastic diplegia, hemiplegia or tetraplegia with or without mental retardation) was diagnosed in 11.1% (4/36) of the cases and in none of the 76 controls (P = 0.011). After adjustment by logistic regression analysis for the effect of confounders (gestational age, birthweight, social class and duration of mother's education) the odds ratio of a poor outcome defined as neonatal death or cerebral palsy was 4.4 (95% confidence interval, 1.2-17.0) in index cases as a whole and 8.0 (95% confidence interval, 1.5 to 43.0) in the subgroup of infants born after severe abruption. Mild abruption did not affect the 2-year infant outcome in both univariate and multivariate analysis.