No change in developmental outcome with incubator covers and nesting for very preterm infants in a randomised controlled trial.

OBJECTIVE: To investigate in a randomised controlled trial the effect of basic elements of developmental care (incubator covers and positioning aids) on growth and neurodevelopment in infants born at < 32 weeks. METHOD: Infants were randomised within 48 h of birth to a developmental care (DC) or standard care (C) group. Outcome measures at 1 and 2 years corrected age were growth, standardised neurological examinations, and mental (MDI) and psychomotor (PDI) development (Dutch version of the Bayley Scales of Infant Development II). RESULTS: 192 infants were recruited (DC = 98; C = 94). Thirteen infants (DC = 7, C = 6) were excluded because they were admitted for <5 days or died within the first 5 days. In total, 179 infants met the inclusion criteria. In-hospital mortality was 12/91 (13.2%) in the DC group and 8/88 (9.1%) in the C group. Assessments were carried out on 147 children (DC = 74, C = 73) at 1 year and 142 children (DC = 72, C = 70) at 2 years. No significant difference in growth, neurological outcomes or MDI was found. A positive trend in PDI at 1 year (p = 0.05) did not continue once the children reached 2 years. There was no difference found when neurological and developmental scores were combined. CONCLUSIONS: Basic developmental care has no positive effect on neurological and mental development or growth at 1 and 2 years of age in infants born at <32 weeks. A positive effect on psychomotor development at 1 year did not continue at 2 years of age.

Is hypotension a major risk factor for neurological morbidity at term age in very preterm infants?

OBJECTIVE: To investigate the influence of perinatal risk factors, especially hypotension, on neuromotor status at term in surviving preterm infants born before 32 weeks of gestation. METHODS: This study is part of the Leiden Follow-Up Project on Prematurity: a prospective, regional study of 266 live born infants with a gestational age (GA) < 32 weeks born in 1996-1997. Twenty-eight infants died before term age. Two hundred and eleven infants were examined neurologically at term according to Prechtl. The findings were classified as normal (N), mildly abnormal (MA) or definitely abnormal (DA). Hypotension was defined as a mean arterial blood pressure (MABP) < 30 mm Hg on at least two occasions. RESULTS: One hundred and six (50%) infants were classified as neurologically N, 92 (44%) infants were classified as MA and 13 (6%) infants as DA. Hypotension, bronchopulmonary dysplasia (BPD), flaring and cystic periventricular leucomalacia (PVL) were risk factors for neurological morbidity. Of the 68 infants with hypotension, 33 (49%) were classified as MA and 7 (10%) as DA. Of the 141 infants without hypotension, 58 (41%) were MA, and 5 (4%) were DA. The odds ratio of hypotension for neurological morbidity was 1.9 (95% CI 1.06-3.40), adjusted for gestational age, birth weight, small for gestational age (SGA) and gender, it was 1.96 (95% CI 1.02-3.77). The adjusted odds ratio of PVL was 18.6 (4.4-78.5), of flaring was 2.37 (1.18-4.74) and of BPD was 2.44 (1.08-5.5). CONCLUSIONS: Apart from gestational age, periventricular leucomalacia, and bronchopulmonary dysplasia, hypotension in preterm infants is a major risk factor for neurological morbidity at term.

Behaviour at 2 years of age in very preterm infants (gestational age < 32 weeks).

AIM: The objective of this study was to determine behavioural outcome and risk factors for abnormal behaviour at 2 y corrected age in very premature infants in a regionally defined, prospective cohort study. METHODS: The Leiden Follow-Up Project on Prematurity includes all liveborn infants of < 32 wk gestational age, born in 1996/1997 (n = 266). Behaviour was assessed with the Child Behaviour Checklist 2-3. RESULTS: An analysis of 158 questionnaires of 206 survivors (77%) was carried out. Fourteen children (9%) had a total problem score > p90 ("clinical range"). This percentage is comparable with the 10% found in a sample of 2- to 3-y-olds from the Dutch general population. Univariate analysis showed higher syndrome scale scores in one or more of the Child Behaviour Checklist scales in children of lower gestational age, small for gestational age (birthweight < p10), with neurological abnormalities at term or at 2 y and of non-Dutch origin. Lower socioeconomic status and postnatal treatment with dexamethasone were associated with higher scores in the somatic problems scale and lower maternal age at birth with a higher total problem score. After correction for confounding variables, the associations between small for gestational age, neurological abnormalities at 2 y and the anxious/depressed and/or withdrawn scales remained significant. CONCLUSION: The prevalence of behavioural problems at 2 y corrected age in this cohort of very premature infants (gestational age < 32 wk) was comparable with that in a general population sample. Children born small for gestational age or with neurological abnormalities at 2 y of age had higher syndrome scale scores, mainly for anxious/depressed and/or withdrawn behaviour.

Etiology of nephrocalcinosis in preterm neonates: association of nutritional intake and urinary parameters.

BACKGROUND: Nephrocalcinosis (NC) in preterm neonates has been described frequently, and small-scale studies suggest an unfavorable effect on renal function. The etiologic factors have not yet been fully clarified. We performed a prospective observational study to identify factors that influence the development of NC. METHODS: The study population consisted of 215 preterm neonates with a gestational age <32 weeks. Clinical characteristics and intake in the first four weeks of calcium, phosphorus, vitamin D, protein, and ascorbic acid were noted. Serum calcium, phosphate, vitamin D, magnesium, uric acid, creatinine, urea and urinary calcium, phosphate, oxalate, citrate, magnesium, uric acid, and creatinine were assessed at four weeks of age and at term. Renal ultrasonography (US) was performed at four weeks and at term. At term was defined as a postconceptional age of 38 to 42 weeks. RESULTS: NC was diagnosed by means of US in 33% at four weeks and in 41% at term. Patients with NC at four weeks had a significantly higher mean intake of calcium (P < 0.05), phosphorus (P < 0.05), and ascorbic acid (P < 0.01) than patients without NC. They had a higher mean serum calcium (2.55 vs. 2.46 mmol/L, P < 0.01) and a higher mean urinary calcium/creatinine ratio (2.6 vs. 2.1 mmol/mmol, P < 0.05). Patients with NC at term had a lower birth weight (1142 vs. 1260 g, P < 0.05) and a lower gestational age (28.8 vs. 29.4 weeks, P < 0.05), were treated significantly longer with furosemide, dexamethasone, theophylline, and thiazides, developed chronic lung disease more frequently (40 vs. 16%, P < 0.001), and had a higher mean urinary calcium/creatinine ratio (2.7 vs. 2.3 mmol/mmol, P < 0.05) and a lower mean urinary citrate/calcium ratio (1.1 vs. 1.7 mmol/mmol, P = 0.005). CONCLUSIONS: NC develops as a result of an imbalance between stone-inhibiting and stone-promoting factors. A high intake of calcium, phosphorus, and ascorbic acid, a low urinary citrate/calcium ratio, a high urinary calcium/creatinine ratio, immaturity, and medication to prevent or treat chronic lung disease with hypercalciuric side effects appear to contribute to the high incidence of NC in preterm neonates.

Ultrasonographic features of nephrocalcinosis in preterm neonates.

Nephrocalcinosis (NC) in preterm neonates has been reported frequently and small studies suggest an unfavourable effect on renal function. Data on ultrasonic features are limited and the reproducibility of ultrasonography (US) in detecting NC in preterm neonates is unknown. In this study, interobserver and intraobserver agreement of US was determined through videotape recordings of US examinations of preterm neonates. Furthermore, a prospective US study was performed in 215 preterm neonates (gestational age < 32 weeks) to evaluate ultrasonic characteristics, incidence, time course and effect on kidney length of NC. Patients were studied at 4 weeks after birth and at term. Patients with NC were followed for 2 years. NC was defined as bright reflections in the medulla or cortex seen in both transverse and longitudinal direction. The length of the kidneys was noted. The kappa value was 0.84 for intraobserver and 0.46 for interobserver agreement, whereas the overall agreement was 73%. NC was found in 50 of 150 (33%) patients at 4 weeks and in 83 of 201 patients (41%) at term. NC was localized mainly in the medulla. At 1 and 2 years, NC had persisted in 36% and 26%, respectively, of the patients with NC at term. Kidney length was comparable with normal values. In conclusion, US has a very good intraobserver agreement but a moderate interobserver agreement in detecting NC. Medullary NC is common among preterm neonates. During the first 2 years of life, the incidence decreases spontaneously and NC does not influence kidney length.

Fetal and neonatal cerebral blood velocity in the normal fetus and neonate: a longitudinal Doppler ultrasound study.

In a longitudinal Doppler ultrasound study fetal and early neonatal cerebral blood flow velocities were assessed in the middle cerebral artery in 40 uncomplicated pregnancies during the third trimester of pregnancy and in 22 neonates born from these pregnancies. Peak systolic (PSFV), temporal mean (TMFV), and end diastolic flow velocities (EDFV) were determined and pulsatility index (PI = (PSFV - EDFV)/TMFV) and Pourcelot's resistance index (RI = (PSFV - EDFV)/PSFV) calculated. PSFV, TMFV and EDFV increased during the third trimester of pregnancy and were significantly higher from 36 weeks of gestation onward as compared to values obtained at 28 weeks of gestation, suggesting an increase in actual cerebral blood flow. PI and RI of the MCA did not differ significantly during this period. Immediately after birth PSFV, TMFV and EDFV decreased significantly and remained lower during the first 5 postnatal days compared to fetal values. PI and RI of the MCA tended to decrease during the first postnatal day, but stabilized afterwards.

Superior mesenteric artery blood flow velocity and estimated volume flow: duplex Doppler US study of preterm and term neonates.

To obtain information about intestinal hemodynamics of healthy neonates, the authors assessed velocity and volume of blood flow with duplex Doppler sonography in the superior mesenteric artery (SMA) in 91 stable preterm and term neonates. Blood flow velocity in the SMA and estimated volume blood flow increased linearly with gestational age and increasing body weight. The mean estimated volume blood flow (+/- standard deviation) was 43 mL/kg/min +/- 13 and did not depend on differences in body weight. The authors also assessed blood flow velocity in the SMA and volume blood flow in 18 infants with conditions that may affect blood supply to the bowel. Twelve infants who were small for gestational age appeared to have an abnormally low resistance of the vascular bed of the SMA during the 1st days of life, as compared with stable appropriate-for-gestational-age infants matched for gestational age. Three of six term neonates with cardiovascular abnormalities had left ventricular outflow obstruction and an abnormal blood flow velocity waveform of the SMA, suggesting a decrease in blood supply to the bowel. The results of this study may help in evaluations of intestinal perfusion in infants with abnormal conditions.