Long-term follow up of children exposed in utero to nifedipine or ritodrine for the management of preterm labour

OBJECTIVE

To compare the long-term psychosocial and motor effects on children exposed in utero to nifedipine or ritodrine for the management of preterm labour.

DESIGN

Randomised controlled trial.

SETTING

Multicentre study in two university and one primary hospital in the Netherlands.

POPULATION

In the original trial, 185 women were randomised to either nifedipine (n = 95) or ritodrine (n = 90). Of the 185 liveborn children, 171 survived (92%), and of these 102 (61%) were followed up at age 9-12 years.

METHODS

Age-specific questionnaires were administered to the parent and teacher. Additional data were obtained from medical records.

MAIN OUTCOME MEASURES

Questionnaires were used to assess the child's behavioural-emotional problems, quality of life (QoL), motor functioning, parenting distress and the child's education.

RESULTS

Of the 171 eligible families, 102 (61%) agreed to participate and completed the questionnaires. Response was equal in the ritodrine group (n = 54 of 83 surviving children, 65%) compared with the nifedipine group (n= 48 of 88 surviving children, 55%). After controlling for differing perinatal characteristics at birth, no significant differences between the groups were detected with respect to long-term behaviour-emotional outcome, QoL, education, motor functioning or parenting distress. Psychosocial outcome was slightly better in the nifedipine group.

CONCLUSIONS

The results do not support any differential postnatal effect of the tocolytic agents ritodrine or nifedipine on the child's long-term psychosocial and motor functioning. The slightly better outcome of children randomised in the nifedipine group is most likely due to more favourable perinatal outcomes in this group. These results merit further investigation in a larger group of survivors.

Study of a group of extremely preterm infants (25-27 weeks): how do they function at 1 year of age?

The functional outcome of 49 extremely preterm infants (gestational age: 25-27 weeks) was studied at the corrected age of 12 months. Apart from pediatric follow-up, a full neurologic assessment and the Bayley Motor and Mental Scales of Infant Development was done. Emphasis was placed on postural control, spontaneous motility, hand function, and elicited infantile reactions. Special attention was given to symmetric development. The infants were then categorized as having optimal or nonoptimal or asymmetric outcome. Overall, an optimal outcome was found in 19 infants (39%) and nonoptimal outcome in 30 infants (61%), 7 of whom failed on all domains of function. Postural control had a significant influence on the different domains of development such as motility (P < or = .001) and persistent infantile reactions (P < or = .001) and slightly less on hand function (P = .08) and asymmetry (P = .06). The outcome on spontaneous motility was significantly related to the results on infantile reactions (P < or = 005) and hand function (P = .05). Also, the score on the motor scale of the Bayley Developmental test was clearly related to outcome on spontaneous motility (P < or = .001) and reactions (P< or = .02). Abnormal brain ultrasonograms were related to the asymmetry of the infantile reactions (P < or = .05). Poor coordination of gross motor function will have consequences for appropriate visuomotor and sensorimotor integration, thereby hampering motor learning and later cognitive function, as is often described in preterm infants. It is suggested that the poor postural control found in many infants born preterm is the result of both myogenic and neurogenic deviations caused by the preterm birth and its nursing consequences.

Muscle power in "high-risk" preterm infants at 12 and 24 weeks corrected age: a measure for early detection

A group of 72 "high-risk" preterm infants was studied at the corrected ages of 12 and 24 wk. Only infants with a high risk for developmental deviance with gestational ages below 32 wk and/or birthweights of less than 1500 g were included in the study. In addition, the infants were categorized according to their medical history, as confirmed by the "Neonatal Medical Index" (NMI I to V), with category I describing infants with few medical problems and V characterizing those with the most serious complications. In this study we included only "high-risk" infants as categorized in NMI III to V, since infants with a "low risk" have been described earlier. Apart from the standard paediatric follow-up, an age-adequate neurological assessment was made, with special emphasis on the relationship between active and passive muscle power. When development is optimal, these two components of muscle power should be in balance in order to create a stable posture and fluent motility. We compared muscle power at the corrected ages of 12 and 24 wk to determine whether the method employed to assess muscle power could enhance early detection of deviant development. At 12 wk of age, only 5 infants showed overall optimal muscle power, while at 24 wk this figure had increased to 27. Significantly more infants in NMI III had optimal outcomes at 24 wk of age. When muscle power in the different parts of the body was studied separately at 24 wk, outcomes in shoulders and trunk still showed significant discrepancies in all NMI groups. At this age, fewer asymmetries were found compared to outcomes at 12 wk.

CONCLUSION

Our method of assessing muscle power is useful in detecting preterm infants at risk for pathological development.

The influence of postural control on motility and hand function in a group of 'high risk' preterm infants at 1 year of age

The functional outcome of a group of 75 'high-risk' preterm infants was studied at the corrected age of 12 months. Only infants with high-risk for developmental deviance with gestational ages below 32 weeks and/or birthweights less than 1500 g were included in the study. Additionally the infants were categorised according to their medical history conforming with the 'Neonatal Medical Index' (NMI I to V), with category I describing infants with few medical problems and V characterizing those with the most serious complications. In this study we included only infants with 'high-risk' as categorised in NMI III to V, since infants with 'low-risk' have been described earlier. Infants with cerebral ultrasonographic abnormalities were incorporated into the NMI categories, but also analysed separately to compare outcomes. At 12 months (corrected age) apart from pediatric follow-up, a full neurological assessment was done with emphasis on postural control, spontaneous motility and hand function. Special attention was given to symmetrical development. The infants were then categorised as having optimal, non-optimal or asymmetrical outcomes. An overall optimal outcome on postural control was found in 64% of all infants (67% in NMI III, 60% in NMI IV and 62.5% in NMI V). Too much extension interfering with postural control was found significantly more often in infants in NMI V (15%), compared to infants in NMI IV (8%) and NMI III (4.5%). Poor postural control had a significant influence on other domains of development such as motility (P=0.00), asymmetry (P=0.00) and hand function (P=0.00). Cerebral ultrasonographic abnormalities seemed to have an influence on motility (P=0.03), while no direct relationship was found with postural control, hand function or asymmetry. It is unclear whether this poor coordination of gross motor function will have consequences for appropriate visual-motor and sensorimotor integration therewith hampering later cognitive function, as often described in preterm infants. It is suggested that the poor postural control found in many infants is the result of both myogenic and/or neurogenic deviations and associated with cerebral pathology, but is also caused by the preterm birth and its nursing consequences.

Muscle power and medical history in high risk preterm infants at 3 months of corrected age

A group of 73 "high risk" preterm infants was studied at the corrected age of 12 weeks. The infants were categorized according to their medical history in 5 classes conform with the "Neonatal Medical Index" (NMI). Only infants with high-risk for developmental discrepancies with a score of NMI > or = III were included in the study. Apart from pediatric follow-up and an age-adequate neurological examination, special emphasis was put on measuring a specific feature in the development of preterm infants: the relationship between active muscle power and passive tone. These two components of muscle power should be in balance with each other to create stable posture and fluent motility and later co-ordination. Discrepancy between active and passive muscle tone was found in all NMI groups studied and was most outspoken in the legs. Infants in NMI IV and V showed a significantly higher incidence of increased passive tone than the infants in NMI III. When the different regions of the body were studied separately, the infants in NMI IV and V showed significantly increased passive tone in the trunk and shoulders (p 0.009) compared to infants in NMI III, which may constitute an alarm signal of deviant development. The main aim of the study was to provide a clinical method for early detection, subtle enough to select infants most at risk for later functional and neurological problems.

Prematurity, posture and the development of looking behaviour during early communication

This study concerns the developing relationship between motor control and looking behaviour in full term (N = 15) and pre-term (N = 29) infants during face-to-face interaction with the mother at 6, 12 and 18 weeks of corrected age. Infants with inborn errors or major medical complications were excluded. In the pre-term infants the development of head and arm postures during interaction differed from the full term pattern, especially in infants born before 32 weeks and/or small-for-gestational age. The full term infants were more advanced than other infants in the ability to grasp an object. These findings were related to group differences in looking behaviour, suggesting that differences in the development of looking behaviour may be (partly) accounted for by differences in the development of motor control.

[Behavior characteristics of 10-year-old ex-neonatal intensive care patients]

Subject of study was the analysis of behavioral characteristics of 51 10-year-old ex-NICU patients at home and at school. Parental assessment of child behavior proved not to differ from the normative data. Teachers however reported more problematic behaviors, particularly with regard to the introverted behavior in boys. On the basis of these findings one can conclude that the prognosis for this patient group is better than expected. A plea is made for future research to focus on factors that will facilitate a more favorable behavior development.

Zellweger syndrome in a preterm, small for gestational age infant

A preterm (gestational age 34 weeks), small for gestational age infant (birth weight less than P2,3) is described. Because of unexplained slightly disturbed liver function tests at age 2 months, extensive metabolic examinations were performed. Elevated blood levels of very long-chain fatty acids, pipecolic acid and abnormal levels of bile acid intermediates were detected, suggesting a peroxisomal disorder. The plasmalogen content of erythrocytes was decreased. Morphologically distinct peroxisomes were absent in the liver. In fibroblasts an accumulation of very long-chain fatty acids, decreased activity of acyl-CoA:dihydroxyacetone phosphate acyltransferase and impaired de novo biosynthesis of plasmalogens was found. In summary, a mild variant of the classical cerebro-hepato-renal syndrome of Zellweger was found without the characteristic clinical facial signs.

Hematocrit in relation to Apgar scores in SGA infants

SGA infants have an increased incidence of low Apgar scores. At the same time they frequently have a high hematocrit. Since both affect outcome, it is important to know if a relationship exists between these two factors. In a study of 139 SGA newborns many had low Apgar scores at one minute: 63% of the preterms and 29% of the fullterms. Frequent abnormal hematological findings included high hematocrit. We found a positive correlation between hematocrit and the Apgar score at one minute of life that was statistically significant. The babies with a high hematocrit had significantly more often good Apgar scores. The correlation was present in preterm babies (r = 0.55) as well as in fullterms (r = 0.32). It is concluded that a high hematocrit probably protects the SGA newborn against acute perinatal asphyxia. It is possible that both low Apgar scores and "normal" hematocrit are signs of a chronically impaired SGA fetus.

Ocular examination in nine-month-old infants with very low birthweights

In the period 1980-1987 ocular examinations were performed on 185 infants with a very low birthweight (less than 1500 g) at the age of nine months corrected for the duration of pregnancy. The mean gestational age of the infants was 30 weeks, while the mean birthweight was 1160 g. The mean spherical refraction was 0.9 D (S.D. 1.3 D), the mean astigmatism was C-0.6 D (S.D. 1.0 D), while convergent strabismus was found in 10% of the patients. The purpose of the investigation was to see if there was a relation between spherical equivalent of refraction, astigmatism and strabismus on the one hand and 11 perinatal parameters and cerebral palsy diagnosed at the age of nine months on the other hand. Statistical analysis was performed with the Student t-test. No significant correlation between the findings of ocular examination and the perinatal parameters could be detected.

[Congenital laryngeal stenosis; a rare cause of dyspnea in the newborn infant]

Congenital laryngeal obstruction is a rare but serious cause of severe, often fatal, post partum asphyxia. The condition should be recognized and in most cases an artificial airway has to be established immediately because hypoxia allows little time for extensive evaluation. Thereafter a further diagnostic procedure by means of laryngobronchoscopy and contrast laryngography should be performed. The clinical picture of two cases with a congenital laryngeal stenosis is described and the initial therapeutic approach is discussed.

Karyotyping urine sediment cells confirms trisomy 12 mosaicism detected at amniocentesis

A newborn is described in whom trisomy 12 mosaicism was detected prenatally at third trimester amniocentesis during the fourth pregnancy of a 34-year-old woman. After birth, trisomy 12 cells were found in placental tissue and in cultured urine sediment cells. A sample of cord blood and a skin biopsy revealed only normal (46,XX) cells. Both parents had a normal karyotype. After a difficult start with unexplained hypoglycaemias and convulsion equivalents, the girl is doing well at the age of 9 months: there are no signs of central motor disturbance. The importance of the use of cultured urine sediment cells in confirming chromosomal mosaicism is stressed.