Wayne L. Andrews

The epidemiology of clinical neonatal seizures in Newfoundland : A population-based study

OBJECTIVE To study the incidence, clinical features, etiologic distribution, and day of seizure onset by etiology in neonates with seizures. DESIGN Prospective, population-based study involving all the obstetric and neonatal units across the province of Newfoundland, Canada. All units were given educational sessions on neonatal seizure symptomatology. SUBJECTS Detailed questionnaires were prospectively collected for all infants with probable neonatal seizures for a period of 5 years. RESULTS The incidence rate was 2. 6 per 1000 live births, 2.00 for term neonates, 11.1 for preterm neonates, and 13.5 for infants weighing <2500 g at birth. Seizures lasting 30 minutes or longer were present in 5%, and the neonatal death rate among infants with seizures was 9%. Hypoxic-ischemic encephalopathy was the presumed cause in 40%, infections in 20%, and metabolic abnormalities in 19%. CONCLUSIONS Clinical neonatal seizures occur 6 times more often in preterm infants than in term infants. Hypoxic-ischemic encephalopathy continues to be a major marker of the likelihood of seizures.

Zinc supplementation in very-low-birth-weight infants

Inadequate zinc intake may lead to poor growth and developmental outcome in very-low-birth-weight (VLBW; < 1,500 g) infants. Fifty-two infants (mean birth weight, 1,117 +/- 287 g; mean gestational age, 29 +/- 2.9 weeks) were randomly allocated to two groups. SUPP infants received a regular term formula plus zinc supplements (4.4 mg/L; final content, 11 mg/L); PLAC infants received the same formula plus placebo (final content, 6.7 mg/L). Infants started their formula at 1,853 +/- 109 g and consumed the formula for 6 months. All subjects were evaluated at 3, 6, 9, and 12 +/- 0.75 months corrected-for-gestational-age. At each evaluation, weight, length, and head circumference were measured, a Griffiths developmental assessment was performed, and a blood sample was taken. Higher plasma zinc levels (p < 0.05) were found in the SUPP group at 1 and 3 months, and improved linear growth velocity was found in the SUPP group over the study period for the whole group as well as for girls alone. Maximum motor development scores were higher (p = 0.018) in the SUPP (98 +/- 10) than the PLAC (90 +/- 8) group, indicating that increased zinc intake in early infancy may be beneficial to VLBW infants.

A double-masked, randomized control trial of iron supplementation in early infancy in healthy term breast-fed infants

OBJECTIVES To test whether iron supplementation affects hematologic, biochemical, and developmental status in term breast-fed infants. STUDY DESIGN Term breast-fed infants (n=77) were randomly selected to receive either 7.5 mg per day of elemental iron as ferrous sulfate or placebo from 1 to 6 months of age. Investigators and families were unaware of group assignment. Complete blood count and ferritin, red cell superoxide dismutase, catalase, plasma ferric reducing antioxidant power, and zinc and copper levels were analyzed at 1, 3.5, 6, and 12 months of age. Bayley mental and psychomotor developmental indexes (MDI and PDI) and visual acuity (with the use of Teller acuity cards) were assessed from 12 to 18 months of age. Analysis performed by analysis of variance and t tests was by intention to treat. RESULTS Iron supplementation resulted in higher hemoglobin and mean corpuscular volume at 6 months of age and significantly higher visual acuity and PDI at 13 months of age (100+/-12 vs 93+/-9 [+/-SD]). Treatment and placebo groups did not differ in anthropometric indexes, compliance, biochemical status, or demographic characteristics. CONCLUSIONS Iron supplementation of breast-fed infants appears safe and might have beneficial hematologic and developmental effects for some infants.

Outcomes of preterm infants <29 weeks gestation over 10-year period in Canada: a cause for concern?

Objective:To compare risk-adjusted changes in outcomes of preterm infants <29 weeks gestation born in 1996 to 1997 with those born in 2006 to 2007.Study Design:Observational retrospective comparison of data from 15 units that participated in the Canadian Neonatal Network during 1996 to 1997 and 2006 to 2007 was performed. Rates of mortality and common neonatal morbidities were compared after adjustment for confounders.Result:Data on 1897 infants in 1996 to 1997 and 1866 infants in 2006 to 2007 were analyzed. A higher proportion of patients in the later cohort received antenatal steroids and had lower acuity of illness on admission. Unadjusted analyses revealed reduction in mortality (unadjusted odds ratio (UAOR): 0.83, 95% confidence interval (CI): 0.63, 0.98), severe retinopathy (UAOR: 0.68, 95% CI: 0.50 to 0.92), but increase in bronchopulmonary dysplasia (UAOR: 1.61, 95% CI: 1.39 to 1.86) and patent ductus arteriosus (UAOR: 1.22, 95% CI: 1.07 to 1.39). Adjusted analyses revealed increases in the later cohort for bronchopulmonary dysplasia (adjusted odds ratio (AOR): 1.88, 95% CI: 1.60 to 2.20) and severe neurological injury (AOR: 1.49, 95% CI: 1.22 to 1.80). However, the ascertainment methods for neurological findings and ductus arteriosus differed between the two time periods.Conclusion:Improvements in prenatal care has resulted in improvement in the quality of care, as reflected by reduced severity of illness and mortality. However, after adjustment of prenatal factors, no improvement in any of the outcomes was observed and on the contrary bronchopulmonary dysplasia increased. There is need for identification and application of postnatal strategies to improve outcomes of extreme preterm infants.

Variations in rates of nosocomial infection among Canadian neonatal intensive care units may be practice-related

BackgroundNosocomial infection (NI), particularly with positive blood or cerebrospinal fluid bacterial cultures, is a major cause of morbidity in neonatal intensive care units (NICUs). Rates of NI appear to vary substantially between NICUs. The aim of this study was to determine risk factors for NI, as well as the risk-adjusted variations in NI rates among Canadian NICUs.MethodsFrom January 1996 to October 1997, data on demographics, intervention, illness severity and NI rates were submitted from 17 Canadian NICUs. Infants admitted at <4 days of age were included. NI was defined as a positive blood or cerebrospinal fluid culture after > 48 hrs in hospital.Results765 (23.5%) of 3253 infants <1500 g and 328 (2.5%) of 13228 infants ≥1500 g developed at least one episode of NI. Over 95% of episodes were due to nosocomial bacteremia. Major morbidity was more common amongst those with NI versus those without. Mortality was more strongly associated with NI versus those without for infants ≥1500 g, but not for infants <1500 g. Multiple logistic regression analysis showed that for infants <1500 g, risk factors for NI included gestation <29 weeks, outborn status, increased acuity on day 1, mechanical ventilation and parenteral nutrition. When NICUs were compared for babies <1500 g, the odds ratios for NI ranged from 0.2 (95% confidence interval [CI] 0.1 to 0.4) to 8.6 (95% CI 4.1 to 18.2) when compared to a reference site. This trend persisted after adjustment for risk factors, and was also found in larger babies.ConclusionRates of nosocomial infection in Canadian NICUs vary considerably, even after adjustment for known risk factors. The implication is that this variation is due to differences in clinical practices and therefore may be amenable to interventions that alter practice.

ELEMENTAL COMPOSITION OF HUMAN MILK FROM MOTHERS OF PREMATURE AND FULL-TERM INFANTS DURING THE FIRST 3 MONTHS OF LACTATION

To examine longitudinal and gestational effects of mineral content in human milk, we analyzed human milk from lactating mothers of premature (PRT,n = 24, < 2000g birth weight, < 37 wk gestation) and fullterm (FT,n = 19, > 2500g, 39–41 wk gestation), living in Newfoundland, Canada. Samples were collected once a week for 8 wk with one final sample collected at 3 mo. Milk samples collected in acid-washed containers were wet ashed with concentrated HNO3, and barium, cadmium, calcium, cesium, cobalt, copper, cerium, lanthanum, magnesium, manganese, molybdenum, nickel, lead, rubidium, tin, strontium, and zinc were measured using inductively coupled plasma-mass spectrometry. Data were analyzed using standard multiple-regression procedures with correlated data analyses to take account of the relationship between successive weeks. Results indicated lower Ca and Pb in PRT milk. Calcium was the only nutritionally significant element to differ between groups. Molybdenum in both PRT and FT milk showed a definite decrease with time, suggesting that the Mo content in milk is homeostatically regulated. However, Ce, La, Ba, and Sn did not display any pattern indicative of biological regulation and potential human requirement.

Intravenous Iron Administration to Very-Low-Birth-Weight Newborns Receiving Total and Partial Parenteral Nutrition

BACKGROUND Intravenous iron supplements are not routinely administered to very-low-birth-weight newborns receiving total parenteral nutrition because of the possible increased risk of infection and because iron needs may be met with blood transfusions. METHODS To assess the benefits of a prudent IV iron supplement (200 to 250 micrograms/kg/d), 26 very-low-birth-weight newborns (birth weight, 1005 +/- 302 g; gestational age, 28 +/- 2.3 weeks; mean +/- SD) were randomly allocated to receive total parenteral nutrition without iron (No-Iron) or with iron supplied as iron dextran (Iron). These newborns were followed at baseline (2 to 3 days after birth) and at weeks 1 to 4 thereafter. At each sampling time, urine samples, fecal samples (rarely), unused total parenteral nutrition solutions, blood products, and a blood sample (1 mL) were collected. RESULTS There were no differences between the two groups in anthropometric measurements, hematologic or biochemical parameters, number or amount of blood transfusions (2.3 +/- 1.9), amount of blood removed for diagnostic purposes (44 +/- 16 mL), or number of septic events (n = 16). There was no difference between the groups for the total iron excreted; however, the Iron group retained more iron. Iron balance was negative for all but 10 newborns (No-Iron, 3; Iron, 7) throughout the study. CONCLUSIONS A total iron intake of 400 micrograms/kg/d, half of which was provided by IV iron, is not sufficient to maintain iron balance or to meet fetal accretion rates (1000 micrograms/kg/d) in very-low-birth-weight newborns receiving total parenteral nutrition. Furthermore, endogenous iron from blood transfusions does not provide an adequate supply of iron.

Visual acuity development and fatty acid composition of erythrocytes in full-term infants fed breast milk, commercial formula, or evaporated milk

&NA; The effects of feeding breast milk (BM), commercial formula (F), or evaporated cow milk (EM) formula on visual acuity and erythrocyte phosphatidylethanolamine fatty acid levels were examined in full‐term infants. Visual acuity was assessed at 3, 6 (BM, F, EM), and 18 (BM, EM) months, and erythrocyte phosphatidylethanolamine levels were determined at birth, 3, and 6 months of age. Visual acuity was significantly higher in the BM‐fed than in the EM‐fed group at 3 months and at 6 months, with intermediate but not significantly different values in the F‐fed group at both ages. Docosahexaenoic acid levels were significantly higher in the BM‐fed than in the F‐fed or EM‐fed group at 3 and 6 months of age and were lowest in the F‐fed group; this might be related to high levels of linoleic acid in F. F‐fed and EM‐fed infants had lower arachidonic acid levels than did BM‐fed infants at 3 months but not at 6 months.

Selenium Status of Very Low Birth Weight Infants

ABSTRACT: The selenium (Se) intake and status of 82 very low birth weight infants (birth weight 1110 ± 286 g, gestational age 29.2 ± 3 wk, mean ± SD) was assessed at 36.3 ± 3 postconceptional wk, at 40.1 ± 4 wk (hospital discharge), and at 3, 6, 9, and 12 ± 0.75 mo corrected for gestational age. Infants were fed formula containing 0.13 μmol/L (10 μg/L) Se. Se-dependent glutathione peroxidase activity in red blood cells declined corresponding to low Se intakes (μg/kd/d) for the first 6 mo. With increased consumption of solid foods, intakes of dietary Se and Se-dependent glutathione peroxidase activity increased at 9 mo, suggesting that the earlier supply of Se was suboptimal. Se-dependent glutathione peroxidase activity and intakes of Se were lower in males than in females (p < 0.05). We suggest that infant formulas should probably contain 0.26–0.33 μmol/L (20–25 μg/L) Se, particularly those formulas consumed by very low birth weight infants.

Molybdenum Requirements in Low-Birth-Weight Infants Receiving Parenteral and Enteral Nutrition:

Background: Molybdenum (Mo) is an essential trace element required by three enzymatic systems, yet there are no reports of Mo deficiency in infants. Low-birth-weight infants (LBW) might be at risk for Mo deficiency because they are born before adequate stores for Mo can be acquired, they have rapid growth requiring increased intakes, and they frequently receive supplemental parenteral nutrition (SPN) and total parenteral nutrition (TPN) unsupplemented with molybdenum. Methods: To investigate Mo requirements of LBW infants (n = 16; birth weight, 1336 ± 351 g; gestational age, 29.8 ± 2.5 weeks; M ± SD), the authors collected all feeds, urine, and feces prior to TPN (baseline, n = 16, collections = 16), during TPN (n = 9, collections = 19), during SPN (n = 13, collections = 17), and after one week of full oral feeds (FOFs) of formula or human milk (FOF, n = 16, collections = 16). Results: Infant weights at collection times were: 1.3 ± 0.3 g, 1.27 ± 0.4 g, 1.4 ± 0.3 g, and 1.7 ± 0.5 g, respectively. Mo intake...