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Biomedical subjects

N Marlow

Publications and source records attributed to N Marlow.

At least 37 records · Page 2Linked to original sources
PubMed2001

Everyday memory and cognitive ability in children born very prematurely.

In light of recent reports of episodic memory difficulties linked to early childhood hypoxia (Isaacs et al., 2000; Vargha-Khadem et al., 1997), preliminary findings of everyday memory function are reported for 20 children born at or before 32 weeks gestation, compared to 20 children born at term. Memory skills were assessed using the Rivermead Behavioural Memory Test for Children (Wilson, Ivani-Chalian, & Aldrich, 1991) at 5 years of age. Everyday memory problems were not found to be a general feature of children born prematurely, and performance was closely linked to receptive language ability but not general cognitive ability in both groups of children. Three children in the preterm group did obtain scores in the impaired range of the RBMT, and in two of these children memory impairment could not be predicted from their receptive language ability. This suggests an increased risk of everyday memory difficulties in populations of preterm children that may be enhanced in further studies by sampling children with greater risk of hypoxic insult.

Child, Preschool↗
PubMed2000

Neurologic and developmental disability after extremely preterm birth. EPICure Study Group.

BACKGROUND AND METHODS: Small studies show that many children born as extremely preterm infants have neurologic and developmental disabilities. We evaluated all children who were born at 25 or fewer completed weeks of gestation in the United Kingdom and Ireland from March through December 1995 at the time when they reached a median age of 30 months. Each child underwent a formal assessment by an independent examiner. Development was evaluated with use of the Bayley Scales of Infant Development, and neurologic function was assessed by a standardized examination. Disability and severe disability were defined by predetermined criteria. RESULTS: At a median age of 30 months, corrected for gestational age, 283 (92 percent) of the 308 surviving children were formally assessed. The mean (+/-SD) scores on the Bayley Mental and Psychomotor Developmental Indexes, referenced to a population mean of 100, were 84+/-12 and 87+/-13, respectively. Fifty-three children (19 percent) had severely delayed development (with scores more than 3 SD below the mean), and a further 32 children (11 percent) had scores from 2 SD to 3 SD below the mean. Twenty-eight children (10 percent) had severe neuromotor disability, 7 (2 percent) were blind or perceived light only, and 8 (3 percent) had hearing loss that was uncorrectable or required aids. Overall, 138 children had disability (49 percent; 95 percent confidence interval, 43 to 55 percent), including 64 who met the criteria for severe disability (23 percent; 95 percent confidence interval, 18 to 28 percent). When data from 17 assessments by local pediatricians were included, 155 of the 314 infants discharged (49 percent) had no disability. CONCLUSIONS: Severe disability is common among children born as extremely preterm infants.

Cohort Studies↗
PubMed2000

The role of cortical evoked responses in predicting neuromotor outcome in very preterm infants.

To explore the role of posterior tibial somatosensory evoked potentials (SSEP) and flash visual evoked potentials (VEP) in the early prediction of functional brain injury, 93 infants of less than 32 weeks gestation at birth were studied. Neuromotor outcome was defined by clinical examination at the age of 2 years. SSEP, VEP and cerebral ultrasound were compared as predictors of neuromotor outcome. Posterior tibial SSEP were the most accurate single method of predicting neuromotor abnormalities with a 83% positive predictive power for cerebral palsy and a 100% predictive power for abnormal neurology, compared to 17% and 40% for cerebral ultrasound and 38% and 85% for VEP respectively. When SSEP and VEP results were concordant, the positive predictive power for cerebral palsy and abnormal neurology was 100%. Our results suggest that posterior tibial SSEP and VEP are accurate tools in the prediction of outcome in very preterm infants.

Cerebral Palsy↗
PubMed2000

The relationship of genotype to cognitive outcome in galactosaemia.

AIMS: To evaluate the cognitive outcome of a cohort of children with galactosaemia in relation to genotype. METHODS: The cohort was drawn from children notified to the British Paediatric Surveillance Unit galactosaemia study which ran from 1988 to 1990. Cognitive outcome was assessed using the Wechsler Intelligence Scale for Children or the Wechsler Preschool and Primary Scale of Intelligence. Parents completed a questionnaire detailing educational status, and the attending paediatrician returned a questionnaire regarding age at diagnosis and biochemical outcome over the previous two years. RESULTS: A total of 45 children were genotyped: 30 were homoallelic for the Q188R mutation, the remainder being heteroallelic for Q188R with K285N (n = 4), L195P (n = 4), or other mutations (n = 7). Psychometric evaluation was available in 34 cases: mean full scale IQ was 79, verbal quotient 79, and performance quotient 82. Genotype was not related to galactose-1-phosphate (Gal-1-P) concentrations. However, children homoallelic for the Q188R mutation had significantly lower IQ scores than those who were heteroallelic (73. 6 v 94.8). This difference was independent of social and demographic influences and Gal-1-P concentrations over the previous two years. CONCLUSIONS: In children with galactosaemia, cognitive outcome appears to relate to genotype rather than metabolic control, as reflected by Gal-1-P concentrations. The value of measuring Gal-1-P concentrations routinely once successfully established on a galactosaemia diet is questionable as concentrations do not appear to affect outcome. In the UK population, homozygosity for the Q188R mutation is invariably associated with a poor outcome, and there is evidence that variability in neurocognitive outcome is at least part dependent on allelic heterogeneity.

Child↗
PubMed2000

Sensorineural hearing loss and prematurity.

OBJECTIVE: To elucidate clinical antecedents of sensorineural hearing loss (SNHL) in very preterm infants. DESIGN: Case-control study. SUBJECTS: Fifteen children < 33 weeks' gestation with significant SNHL born between 1 January 1990 and 31 December 1994, detected within 9 months of birth, and 30 matched control children. METHODOLOGY: Perinatal variables in the two groups were compared using non-parametric tests and conditional logistic regression (EGRET). RESULTS: Median birth weight for the index group was 960 g (range 600-2914 g) compared with 1026 g (range 410-2814 g) for controls. Children with SNHL had longer periods of intubation, ventilation, oxygen treatment, and acidosis, and more frequent treatment with dopamine or frusemide. Neither peak nor trough aminoglycoside levels, nor duration of jaundice or level of bilirubin varied between groups. However, SNHL was more likely if peak bilirubin levels coexisted with netilmicin use (odds ratio (95% confidence interval) 14.2 (1.8 to 113.6)) or if acidosis occurred when bilirubin levels were over 200 micromol/l (OR 8.0 (0.9 to 71.6). Frusemide use in the face of high serum creatinine levels (OR 8.9 (1.1 to 74.5)) or netilmicin treatment (OR 5.0 (0.99 to 24.8)) was also associated with SNHL. At 12 months of age, seven of 15 children with SNHL had evidence of cerebral palsy compared with two of 30 controls (OR 12.3 (2.1 to 71)). CONCLUSIONS: Preterm children with SNHL required more intensive care in the perinatal period and developed more neurological complications than controls. Among very preterm babies, the coexistence of risk factors for hearing loss may be more important than the individual factors themselves.

Aminoglycosides↗
PubMed2000

The EPICure study: outcomes to discharge from hospital for infants born at the threshold of viability.

OBJECTIVE: To evaluate the outcome for all infants born before 26 weeks of gestation in the United Kingdom and the Republic of Ireland. This report is of survival and complications up until discharge from hospital. METHODOLOGY: A prospective observational study of all births between March 1, 1995 and December 31, 1995 from 20 to 25 weeks of gestation. RESULTS: A total of 4004 births were recorded, and 811 infants were admitted for intensive care. Overall survival was 39% (n = 314). Male sex, no reported chorioamnionitis, no antenatal steroids, persistent bradycardia at 5 minutes, hypothermia, and high Clinical Risk Index for Babies (CRIB) score were all independently associated with death. Of the survivors, 17% had parenchymal cysts and/or hydrocephalus, 14% received treatment for retinopathy of prematurity (ROP), and 51% needed supplementary oxygen at the expected date of delivery. Failure to administer antenatal steroids and postnatal transfer for intensive care within 24 hours of birth were predictive of major scan abnormality; lower gestation was predictive of severe ROP, while being born to a black mother was protective. Being of lower gestation, male sex, tocolysis, low maternal age, neonatal hypothermia, a high CRIB score, and surfactant therapy were all predictive of oxygen dependency. Intensive care was provided in 137 units, only 8 of which had >5 survivors. There was no difference in survival between institutions when divided into quintiles based on their numbers of extremely preterm births or admissions. CONCLUSIONS: This study provides outcome data for this geographically defined cohort; survival and neonatal morbidity are consistent with previous data from the United Kingdom and facilitate comparison with other geographically based data.

Analysis of Variance↗
PubMed1999

Maturation of the flash visual evoked potential in preterm infants.

Flash visual evoked potentials (VEPs) were recorded from 67 infants of < 33 weeks gestation with normal neurological outcome at 24 months corrected age. Cross sectional and longitudinal data showed the emergence of peak components of the waveform with increase in maturity. The first major negative peak, with a latency around 300 ms in the most immature subjects, was the most prominent and consistent component. This peak showed a decrease in latency with increase in post-conceptional age, maturing by a mean rate of 5.5 ms/week. The role of VEPs in predicting brain injury in preterm infants can be determined.

Brain Diseases↗
PubMed1999

UK neonatal intensive care services in 1996. On behalf of the UK Neonatal Staffing Study Collaborative Group.

A census of activity and staff levels in 1996 was conducted in UK neonatal units and achieved a 100% response from 246 units. Among the 186 neonatal intensive care units, the median (interquartile range) number of total cots was 18(14-22); level 1 intensive care cots 4(2-6); total admissions 318(262-405); very low birthweight admissions 40(28-68); and the number ventilated or given CPAP by endotracheal tube 52(32-83). Forty six (25%) intensive care units lacked the recommended minimum of one consultant with prime responsibility for neonatal medicine. As a conservative estimate 79% of intensive care units had a lower nursing provision than that recommended in previously published guidelines. There was substantial variation in activity and staffing levels among units.

Hospital Bed Capacity↗
PubMed1999

Development of a system to record cardiac output continuously in the newborn.

Intermittent recordings of Doppler flow velocity and cardiac output are of value during intensive care of the sick newborn infant but result in repeated disturbance of the child. We describe a new device for making continuous precordial recordings of Doppler flow velocity from the pulmonary artery in healthy resting newborn infants. Optimal probe siting was evaluated in six babies, and signals were found to be best when the pulmonary artery was insonated from the mid left parasternum. Continuous recordings were made in 13 other babies. Pulmonary artery velocities and, by calculation, cardiac output were measured continuously over periods ranging from 24 to 60 min. Median right ventricular output ranged widely from 148 to 246 mL x kg(-1) x min(-1). In contrast, for individual babies, the values were remarkably stable: the interquartile ranges varied from 13.2 to 29.9 mL x kg(-1) x min(-1). The simultaneous display of signal power allowed independent assessment of artifactual changes in cardiac output. This technique is feasible in healthy term infants and now requires evaluation in the intensive care setting where it may provide useful information concerning trends and short-term variability in right ventricular output.

Cardiac Output↗
PubMed1998

Short-term memory and language outcomes after extreme prematurity at birth.

The performance of 26 children (3;0-4;0 years) who were born before 32 weeks gestation was compared with the performance of 26 full-term children on a range of short-term memory and language measures. The measures tested vocabulary, expressive language, phonological short-term memory, and general nonverbal ability. Preterm children scored more poorly across the full range of measures. The mildly depressed performance of the preterm group on the short-term memory and language measures was attributable to the large deficits on these tests shown by a subgroup of approximately one third of preterm children identified as being "at risk" for persisting language difficulties using the Bus Story Test (Bishop & Edmundson, 1987). The findings indicate that preterm birth and associated hazards may constitute a significant risk factor for specific language impairment in a sizable minority of children.

Apgar Score↗
PubMed1998

Cognitive and educational outcome of very-low-birthweight children in early adolescence.

A cohort of 138 very-low-birthweight (VLBW) 12-year-old children and matched control children were assessed on objective cognitive and educational measures. School performance was rated by teachers and by the children themselves. VLBW children were shown to have lower IQ scores, and poorer scores on all objective educational measures compared with control children. Controlling for IQ differences, mathematics and reading-comprehension scores remained significantly lower for VLBW children. Teachers rated VLBW children lower in all curriculum areas. Significantly more VLBW children were found to be 'failing' in one or more subject and an increased proportion compared with the control children had received remedial education. The VLBW group showed no evidence of 'catch up' between 6 and 12 years of age. Multiple regression analyses were used to identify predictors of cognitive and educational outcome. The duration of mechanical ventilation in the neonatal period was inversely related to outcome. Full-Scale IQ at 6 years, motor-skills score at 6 years, and head circumference at 12 years all predicted outcome at 12 years, as did maternal education, family income and size. Individually, many VLBW children perform satisfactorily, but as a group VLBW children appear to be at a long-term disadvantage to peers in the areas of cognitive and educational performance.

Child↗
PubMed1998

Outcome of resuscitation following unexpected apparent stillbirth.

There are few data to inform a decision to resuscitate babies who are unexpectedly stillborn. The outcome for 42 successfully resuscitated stillborn children, of whom 62% survived to be discharged home, is reported. Of the survivors, a poor outcome with severe disability was found in 23% (including one postneonatal death), equivocal outcome was found in 15% (two mild hypertonia; two with mild hemiplegia and no associated other disability) and 62% were free of any impairment at follow up 20 months to 8 years later. In 39 (93%) fetal problems had been identified and the resuscitation team was present at delivery. Poor outcome was associated with late return of heart beat, delayed respirations, neonatal acidaemia and early onset of seizures. Of the unexpected apparent stillbirths successfully resuscitated, 52% died or survived severely disabled, 10% had an equivocal outcome, but 36% survived apparently intact. Therefore, vigorous resuscitation is clearly indicated in these circumstances.

Developmental Disabilities↗
PubMed1998

Randomised controlled trial of L-carnitine as a nutritional supplement in preterm infants.

AIMS: To evaluate the effect of L-carnitine supplementation (25 mg/kg/d) on the growth and incidence of hypoglycaemia in preterm infants. METHODS: A double blind, placebo controlled randomised trial, stratified for gestational age, was conducted of 86 preterm infants between 28 and 34 gestational weeks. The median gestational ages in the carnitine group and placebo groups were 30.7 weeks (range 28.0 to 33.6) and 31.4 weeks (range 28.0 to 33.9), respectively. The median birthweights were 1.557 kg (range 0.944 to 2.275) and 1.645 kg (range 0.885 to 2.545), respectively. RESULTS: Mean plasma free carnitine concentrations were below values for normal term infants in both groups on day 1 (carnitine group 44.8 mumol/l, placebo group 25.5 mumol/l) in the placebo group on day 7 (50.7 mumol/l), but in neither group on days 14 and 28. Total, free, and acylcarnitine concentrations were significantly increased in both urine and blood in the L-carnitine group. There was no significant difference between the placebo and carnitine supplemented groups in growth rate, as assessed by weight, length, skinfold thickness and head circumference measurements, or in the incidence of episodes of hypoglycaemia. CONCLUSION: The addition of carnitine as a nutritional supplement at a dose of 25 mg/kg/day did not improve growth in our group of preterm infants nor protect them from episodes of hypoglycaemia.

Carnitine↗