PubMed Health⌕ Search

Biomedical subjects

G R Pereira

Publications and source records attributed to G R Pereira.

At least 19 recordsLinked to original sources

Necrotizing enterocolitis in neonates with congenital heart disease: risk factors and outcomes.

OBJECTIVE: Necrotizing enterocolitis (NEC) is primarily a disease of the premature infant. Among children born at term, however, congenital heart disease may be an important predisposing factor for this condition. To determine risk factors for NEC in patients with congenital heart disease, we conducted a case-control study of neonates with cardiac disease admitted to the cardiac intensive care unit at our center during the 4-year period from January 1995 to December 1998. METHODS: Cardiac diagnosis and age at admission were analyzed for association with NEC among the 643-patient inception cohort. Demographic, preoperative, and operative variables were recorded retrospectively in 21 neonates with congenital heart disease who developed NEC and 70 control neonates matched by diagnosis and age at admission. Using parametric and nonparametric analysis, cases and controls were compared with respect to previously identified risk factors for NEC. RESULTS: Among the entire cohort of 643 neonates with heart disease admitted to the cardiac intensive care unit, diagnoses of hypoplastic left heart syndrome (odds ratio [OR] = 3.8 [1.6-9.1]) and truncus arteriosus or aortopulmonary window (OR = 6.3 [1.7-23.6]) were independently associated with development of NEC by multivariable analysis. In the case-control analysis, earlier gestational age at birth (36.7 +/- 2. 7 weeks vs 38.1 +/- 2.3 weeks), prematurity (OR = 3.9 [1.2-12.5]), highest dose of prostaglandin >0.05 microg/kg/minute (OR = 3.9 [1. 2-12.5]), and episodes of low cardiac output (meeting specific laboratory criteria) or clinical shock (OR = 6.5 [1.8-23.5]) correlated with the development of NEC. Earlier gestational age and episodes of low output were the only factors that remained significantly associated with NEC by multivariable analysis. Although there was no difference in hospital mortality between patients with and without NEC, mean hospital stay was significantly longer in those who developed NEC (36 +/- 22 days vs 19 +/- 14 days). CONCLUSIONS: The risk of NEC in neonates with congenital heart disease is substantial. Factors associated with an elevated risk of NEC in infants with heart disease include premature birth, hypoplastic left heart syndrome, truncus arteriosus, and episodes of poor systemic perfusion or shock. Heightened suspicion is warranted in newborns with these risk factors.

Case-Control Studies↗

Effects of sweet taste stimulation on growth and sucking in preterm infants.

OBJECTIVE: To evaluate the effect of sweet taste stimulation in augmenting the reported growth-enhancing effects of nonnutritive sucking in preterm infants who are gavage-fed. DESIGN: Random assignment of preterm infants to receive stimulation by one of three methods during each feeding until totally orally fed. SETTING: Hospital intensive-care and infant transitional units. PATIENTS: Eligibility criteria included body weight greater than or equal to 1,250 g, gestational age younger than 34 weeks, growth parameters appropriate for gestational age, tolerating at least 100 kcals/kg/day by gavage feeding with evidence of weight gain, and no clinical evidence of health complications. Data are presented for 42 infants who completed 14 days of treatment. INTERVENTIONS: Exposure to a sweet pacifier, a latex pacifier, or maternal heartbeat sounds during gavage feedings. MAIN OUTCOME MEASURES: Growth, time to total oral feeding, and sucking responses. RESULTS: No significant differences in sucking measures were noted among treatment groups. Differences in progression time to total oral feedings and weight gain favored the sweet-pacifier group but were not statistically significant. CONCLUSIONS: Oral stimulation of gavage-fed, preterm infants during a 2-week hospitalization was not sufficient to elicit a significant improvement in growth efficiency, progression to total oral feedings, or sucking maturation. Additional studies may show a beneficial effect of chemosensory stimulation in preterm infants.

Child Development↗

Nutritional care of the extremely premature infant.

In summary, the nutritional care of extremely premature babies includes special attention to glucose homeostasis and fluid and electrolyte balance in the immediate postnatal period. Parenteral nutrition should be started routinely on the 2nd or 3rd day of life, if the infant is metabolically stable, and continued until the infant is receiving sufficient enteral feedings to promote growth. If not clinically contraindicated, minimal enteral feedings should be started before the end of the first week of life. The decision to either advance or maintain minimal enteral feedings at a constant level should take into account the clinical status of the infant. Fortified preterm human milk is the preferred feeding and premature infant formulas, the best substitute. Multivitamin supplements may be necessary, depending on formula intake. Iron supplements can be initiated as early as 2 weeks of age and high levels of intake appear to be necessary during erythropoietin therapy.

Fluid Therapy↗

Use of high-fat formula for premature infants with bronchopulmonary dysplasia: metabolic, pulmonary, and nutritional studies.

The use of dietary fat in preference to carbohydrate offers the theoretic advantage of diminishing carbon dioxide production and thus the respiratory quotient, which may be beneficial for babies with chronic lung disease. Ten premature infants (birth weight (mean +/- SEM), 1.13 +/- 0.12 kg; postnatal age, 9 +/- 1 weeks) with bronchopulmonary dysplasia were alternately fed a high-fat and a high-carbohydrate formula each for 1 week, in randomized order. Lower rates of carbon dioxide production (6.6 +/- 0.3 versus 7.4 +/- 0.4 ml/kg per minute; p < 0.05), and consequently lower respiratory quotients (0.80 +/- 0.02 versus 0.94 +/- 0.01 ml/kg per minute; p < 0.005), were observed during the administration of the high-fat formula. There were no significant differences in results of pulmonary function tests with the use of either formula. Both formulas were equally well tolerated and able to promote adequate growth and normal biochemical profiles. However, weight gain was significantly greater with the administration of the high-carbohydrate formula, possibly because of an increase in the accretion of body fat. We conclude that the short-term use of high-fat formula for infants with bronchopulmonary dysplasia decreases carbon dioxide production while maintaining adequate growth and nutritional status.

Bottle Feeding↗

Enteral theophylline and necrotizing enterocolitis in the low-birthweight infant.

In a two-phased retrospective study, clinical factors associated with the development of necrotizing enterocolitis (NEC) in neonates were identified. The first phase found 13 infants with NEC who had been treated more frequently with enteral theophylline (P < .025) and fed higher volumes (> 150 mL/kg/day; P < .05) than controls of comparable birthweight and postnatal age. Seven of the 13 infants with NEC, weighing < 1,250 g at birth, had previously received intravenous aminophylline and been changed to enteral theophylline within six days before the onset of NEC. Prolonged rupture of membranes was more prevalent (P < .025) in infants with birthweight > 1,250 g who developed NEC in the first week of life. Maternal preeclampsia helped protect against the development of NEC (P < .05). In the second study phase, 59 infants with birthweights < 1,250 g were evaluated for gastrointestinal disturbance within five days of the introduction of any enteral medication. The frequencies of NEC, NEC scare, and feeding intolerance were greater in infants treated with enteral theophylline than in those treated with all other enteral medications combined (P < .05). This two-phased study confirms the multifactorial etiology of NEC and indicates that the administration of enteral theophylline to young infants < 1,250 g may be a predisposing factor to GI disturbances and NEC. These findings warrant a further prospective investigation.

Administration, Oral↗

Umbilical vs peripheral vein catheterization for parenteral nutrition in sick premature neonates.

The efficacy and safety of using umbilical venous catheters vs. peripheral venous catheters for the delivery of parenteral nutrition was studied in 129 critically ill premature infants who were treated in a neonatal intensive care unit for the first 3 weeks of life. Infants who received parenteral nutrition by umbilical venous catheter had greater parenteral caloric intake, lower physiologic weight loss and greater weight gain during the study as compared to infants who received parenteral nutrition by peripheral vein. While the overall incidence of sepsis was comparable in both groups (19% vs 19.7%), benign and transient episodes of hyperglycemia were seen more commonly in infants receiving parenteral nutrition by umbilical catheters. None of the hyperglycemic infants, however, required insulin therapy. The incidence of other metabolic complication was comparable in both groups. At follow up, no evidence of portal hypertension was detected in any of the infants up to 66 months of age treated with umbilical venous catheters. We conclude that the use of umbilical venous catheter allows for a comparably safe and a more appropriate parenteral nutrition support than peripheral catheters in critically ill premature neonates.

Catheterization, Peripheral↗

Lecithin:cholesterol acyltransferase (LCAT) activity during lipid infusion in premature infants.

Plasma cholesterol and lecithin concentrations are regulated by the serum enzyme lecithin: cholesterol acyltransferase (LCAT). LCAT activity is low in cord blood of premature infants, suggesting that in these infants the hypercholesterolemia associated with Intralipid infusion might be due to low LCAT activity. The serum LCAT activity has not been quantitated in preterm infants receiving intravenous fat emulsions. We have therefore quantitated LCAT activity in eleven premature infants maintained on total parenteral nutrition (TPN). Ten infants were studied during the first 2 weeks after birth; they received daily infusions of Intralipid at a rate of 0.5-2.0 g/kg/day over 15 h. One infant received 3.8 g/kg/day during the second week. In addition to LCAT, serum apoprotein A1 (the cofactor of LCAT), cholesterol, triglycerides, and free fatty acids were quantitated. Blood specimens were taken before the start of the infusion and 15-45 min before its completion. The LCAT activity and apoprotein A1 concentrations remained, respectively, 21-24% and 30-35% of adult levels. However, serum cholesterol levels remained in the normal range during the fat infusion. It remains to be established whether low LCAT activity and apoprotein A1 levels are due to the administration of Intralipid (which lowers LCAT activity in rats), to the lack of enteral feedings, or to prematurity per se. Our data suggest that administration of Intralipid at a rate not exceeding 1-2 g/kg/day does not impair the clearing of Intralipid-lecithin and the metabolism of cholesterol.

Analysis of Variance↗

Serum myoinositol concentrations in premature infants fed human milk, formula for infants, and parenteral nutrition.

Myoinositol concentration was studied in serum of 65 neonates and their mothers at the time of birth, in samples of various types of feedings for infants, and in serial serum samples of 15 premature infants receiving human milk, formulas for infants, or parenteral nutrition over a 3-wk period. At birth the serum concentration of myoinositol was greater in neonates than in their mothers (108 +/- 10 vs 52 +/- 6 mumol/L, respectively, means +/- SEM, p less than 0.01). In feedings for infants, the concentrations of myoinositol were significantly greater in human milk than in formulas or parenteral nutrition solutions (1840 +/- 451 vs 420 +/- 110 vs 100 +/- 8 mumol/L, respectively, p less than 0.001). Over a 3-wk period the serum concentration of myoinositol increased in infants receiving human milk but not in those receiving formulas or parenteral nutrition. Serum concentrations of myoinositol in neonates are greater than in adults and are directly influenced by myoinositol intake.

Adult↗

Nutritional care of the surgical neonate.

The surgical neonate is at great risk of developing nutritional deficiencies. However, recent advances in nutritional support, including the development of special elemental diets, infant formulas, nutritional supplements and more suitable additives for parenteral nutrition, have allowed health professionals effectively to prevent the occurrence of malnutrition in sick neonates. Strict monitoring of dietary intake, growth velocity, and biochemical parameters are essential while providing nutritional support. The complication of parenteral nutrition can be reduced by following standard recommendations for preparing solutions, caring for the central and the peripheral catheters, and biochemically monitoring the infant. The organization of a hospital nutrition support service composed of physicians, nurses, nutritionists, and pharmacists is essential in establishing guidelines for the safe delivery of nutritional therapy and in educating hospital personnel and parents on how to best meet the nutritional needs of the surgical neonate.

Enteral Nutrition↗

Effect of heparin dose and infusion rate on lipid clearance and bilirubin binding in premature infants receiving intravenous fat emulsions.

The effect of heparin dose and infusion rate on plasma lipids, lipases, and unbound bilirubin was investigated in 22 premature infants with physiologic jaundice. Infants were randomly assigned to receive low or high intravenous doses (24 vs 137.3 U/day) of heparin. Each patient then received 2 g/kg/day of 10% Intralipid on 2 successive days: one day during a 15-hour period and the other day over 24 hours, with the order assigned randomly. The results demonstrate a significantly greater change in serum-free fatty acids in infants receiving the high heparin dose during the 15-hour lipid infusion period. Lipoprotein lipase activity rose more with the high heparin dose and equally at either infusion rate. We conclude that lipid infusions of 2 g/kg/day with low heparin dosage infused over 24 hours resulted in less elevation in serum-free fatty acids. There were no adverse effects on unbound bilirubin at either infusion rate or heparin dosage.

Bilirubin↗

A comparison of the mid-arm circumference/head circumference ratio and ponderal index for the evaluation of newborn infants after abnormal intrauterine growth.

We studied the accuracy of the ponderal index and the mid-arm circumference/head circumference ratio for detecting newborn infants who were likely to be symptomatic because of aberrant intrauterine growth. Sixty infants were evaluated because of suspected intrauterine growth retardation; both the mean ponderal index and mid-arm circumference/head circumference ratio were significantly lower in the group of 30 symptomatic infants than in the group of 30 asymptomatic infants (p less than 0.05). However, the mid-arm circumference/head circumference ratio identified a significantly higher percentage of the symptomatic infants than the ponderal index (80% vs. 47%; p = 0.007). An additional 60 infants were evaluated because of suspected abnormal intrauterine growth acceleration. The mean mid-arm circumference/head circumference ratio, but not the ponderal index, was significantly higher in the group of 30 symptomatic infants than in the group of 30 asymptomatic infants (p less than 0.005). Again, the mid-arm circumference/head circumference ratio identified a significantly higher percentage of the symptomatic infants than the ponderal index (79% vs. 33%; p less than 0.001). The mid-arm circumference/head circumference ratio is more accurate than the ponderal index for the evaluation of potentially symptomatic newborn infants who suffered abnormal fetal growth. The ponderal index is not useful for the detection of symptomatic large-for-dates infants.

Arm↗

Mid-arm circumference and mid-arm/head circumference ratios: standard curves for anthropometric assessment of neonatal nutritional status.

Two hundred four neonates, 25 to 42 weeks estimated gestational age (EGA), were measured on day 2 or 3 of life for upper mid-arm circumference (MAC) and head circumference. Regression analysis was used to construct standard curves for MAC versus EGA and mid-arm circumference/head circumference ratio (MAC/HC) versus EGA. Correlation coefficients were 0.93 for MAC versus EGA, and 0.84 for MAC/HC versus EGA. MAC, MAC/HC, and head circumference were also highly correlated with birth weight. These measurements may more accurately assess intrauterine growth and body proportionality at birth than weight, length, and head circumference.

Anthropometry↗

Mid-arm circumference/head circumference ratios for identification of symptomatic LGA, AGA, and SGA newborn infants.

Mid-arm circumference/head circumference ratios (MAC/HC) and birth weights obtained in 73 neonates were studied to compare which of these growth measurements could more accurately predict risk of metabolic complications resulting from either acceleration or retardation of fetal growth. The MAC/HC ratio was more sensitive than birth weight in distinguishing symptomatic large for gestational age (LGA) infants who were born to diabetic mothers from other LGA infants who were asymptomatic, and symptomatic from asymptomatic small for gestational age infants. In addition, the MAC/HC ratio identified symptomatic appropriate for gestational age (AGA) infants born to diabetic mothers and AGA infants with signs and symptoms of growth retardation. The MAC/HC is more useful than birth weight in assessing newborn infants at risk for the metabolic complications associated with fetal growth disorders.

Anthropometry↗

Cord prealbumin values in newborn infants: effect of prenatal steroids, pulmonary maturity, and size for dates.

We assessed cord prealbumin concentrations in 214 appropriate for gestational age newborn infants, 21 small for gestational age infants, and 27 large for gestational age infants to establish normal values and to assess the effect of intrauterine growth, prenatal steroids, and pulmonary maturity on prealbumin levels. Cord prealbumin values were significantly correlated with increasing gestational age (r = 0.33; P less than 0.001) and birth weight (r = 0.40, P less than 0.001) in the AGA neonates. Neonates born before 37 weeks gestation had significantly lower prealbumin levels than those born at term (P less than 0.001). The SGA infants had significantly lower levels than age-matched AGA controls (P less than 0.01), and LGA infants had significantly higher levels than age-matched AGA controls (P less than 0.001). In preterm infants, those with exposure to prenatal steroids (betamethasone or premature rupture of membranes) had significantly higher prealbumin values than control infants of comparable age and weight (P less than 0.001). Infants without respiratory distress syndrome had higher levels than those of comparable age and weight with hyaline membrane disease (P less than 0.05). This study demonstrates that a correlation of gestational age and birth weight exists with cord prealbumin levels, and that the large variability at each gestational age may be accounted for in part by appropriateness of size for dates, prenatal steroid exposure, and pulmonary maturity.

Betamethasone↗

Controversies in neonatal nutrition.

The assessment of growth parameters remains one of the most practical and valuable tools to estimate nutritional status in neonates. Growth assessment in full-term infants is performed by using charts developed by the National Center for Health and Statistics. The assessment of post-natal growth in premature infants is controversial and can be performed by using either intrauterine or extrauterine standards. The selection of appropriate growth charts should be based on clinical, demographic, ethnic, and socioeconomic similarities of the population used for reference. Daily energy intakes ranging from 100 to 120 kcal/kg/day have been recommended for full-term infants, while higher intakes ranging from 114 to 181 kcal/kg/day have been recommended for premature neonates. Full-term infants should be nursed or nipple fed on demand; however, premature infants should ideally be tube fed by intermittent gastric feeding (gavage). Continuous gastric and transpyloric feedings are indicated in selected infants. Human milk is a preferred food for full-term infants during the first six months of life; however, this precept does not suggest that all infants who are exclusively breast-fed will grow adequately. Preterm human milk is also a preferred food for the low birthweight infant, provided nutritional supplements are used. It is unclear whether the supplementation of vitamin D, iron, and fluoride in full-term breast-fed infants should be started at birth, at the time of initiation of solid foods, or at the age of six months. The routine supplementation of multivitamins, folic acid, and vitamin E to all low birthweight infants is controversial. Most investigators suggest vitamin supplementation be given until the intake of formula or breast milk is sufficient to meet daily requirements. Vitamin E appears to exert a protective effect in premature infants against the development of severe retinopathy. The supplementation of vitamin E should be dependent upon the serum vitamin E concentration. It is controversial whether iron supplementation for premature infants should be initiated soon after birth or at two months of age, or whether higher doses of iron should be given to very low birthweight infants. If iron supplementation is started at birth, vitamin E status should be closely monitored. Although the optimal intakes of calcium and phosphorus in infant feedings have not been firmly established, the levels of calcium and phosphorus in human milk appear to be inadequate for the growing low birthweight infant.(ABSTRACT TRUNCATED AT 400 WORDS)

Body Weight↗

Effect of gestational age upon prealbumin and retinol binding protein in preterm and term infants.

The relationships between maternal and umbilical cord levels of prealbumin and retinol binding protein (RBP) were studied in 68 mothers and in their appropriate-for-gestational-age neonates delivered between 25 and 42 weeks gestation. Arterial and venous concentrations of prealbumin and RBP in cord sera were also studied in a subsample of eight infants. In cord sera, prealbumin and RBP levels increased with gestational age (prealbumin, r = 0.47; RBP, r = 0.40, p less than 0.01), and were significantly different in neonates born at term compared to those born prematurely (mean +/- SD, prealbumin 12.0 +/- 3.9 mg/dl vs. 8.8 +/- 2.3 mg/dl, p less than 0.001; RBP, 2.3 +/- 0.8 vs. 1.8 +/- 0.5 mg/dl, p less than 0.005). No significant differences between arterial and venous concentrations of prealbumin and RBP were observed in cord blood. In maternal blood, serum prealbumin and RBP concentrations did not increase with length of gestation (25-42 weeks). Maternal prealbumin was not correlated significantly with infants' cord serum levels; the correlation coefficient for RBP was 0.29, p less than 0.05. Maternal prealbumin and RBP serum levels were approximately twice the values seen in neonates born both at term and prematurely. Although the difference between premature and full-term cord levels of prealbumin and RBP may reflect an increase in hepatic protein synthesis that occurs with maturation of the fetus and/or a change in placental function after 37 weeks gestation, neither of these factors sufficiently explains the variance in neonatal prealbumin and RBP levels.

Female↗