PubMed Health⌕ Search

Biomedical subjects

R J Schanler

Publications and source records attributed to R J Schanler.

At least 37 records · Page 2Linked to original sources
PubMed1999

The use of human milk and breastfeeding in premature infants.

Human milk is beneficial in the management of premature infants. The beneficial effects generally relate to improvements in host defenses, digestion, and absorption of nutrients, gastrointestinal function, neurodevelopment, and maternal psychological well-being. The use of fortified human milk generally provides the premature infant adequate growth, nutrient retention, and biochemical indices of nutritional status when fed at approximately 180 mL/kg/day compared with unfortified human milk. Human milk can only support the needs of the premature infant if adequate milk volumes are produced. Intensive efforts at lactation support are desirable. Therefore, neonatal centers should encourage the feeding of fortified human milk for premature infants along with skin-to-skin contact as a reasonable method to enhance milk production and promote success with early breastfeeding, while potentially facilitating the development of an enteromammary response.

Breast Feeding↗
PubMed1998

Early feeding, feeding tolerance, and lactase activity in preterm infants.

OBJECTIVE: We sought to ascertain whether the timing of feeding initiation affected the development of intestinal lactase activity and whether there are clinical ramifications of lower lactase activity. STUDY DESIGN: Preterm infants (26 to 30 weeks' gestation; n = 135) were randomly assigned to begin enteral feedings at either 4 (early group) or 15 days of age (standard group). At 10, 28, and 50 days of age lactase activity was determined by measuring the urinary ratio of lactulose/lactose after the 2 sugars were administered. RESULTS: Lactase activity increased significantly over time. Infants in the early group had greater lactase activity at 10 days of age (by 100%) and 28 days of age (by 60%) than the standard group. At 10 days of age lactase activity was greater in milk- versus formula-fed infants. The time required to achieve full enteral feedings, the number of abnormal abdominal x-ray examinations, and the total number of abdominal x-ray examinations were inversely related to lactase activity. CONCLUSIONS: Early feeding increases intestinal lactase activity in preterm infants. Lactase activity is a marker of intestinal maturity and may influence clinical outcomes. Whether the effects of milk on lactase activity were due to the greater concentration of lactose in human milk compared with that in formula must be determined.

Age Factors↗
PubMed1998

Iron absorption and red blood cell incorporation in premature infants fed an iron-fortified infant formula.

This study was designed to identify differences in red blood cell (RBC) incorporation and iron absorption in premature infants between iron provided in a premature infant formula compared with iron provided as a supplement between feedings. We used a triple stable isotope technique in which 13 infants received 57Fe mixed with Enfamil Premature Formula on d 1 of the study, and 54Fe with a multivitamin supplement between meals on d 2. Two weeks later, blood was drawn for isotope analysis and 58Fe was given i.v. The percentage RBC incorporation of the 54Fe and 57Fe was calculated, and the percent absorption of these tracers was estimated by dividing by the percentage of 58Fe identified in RBCs 14 d after its infusion. We found a small, but significantly greater, percentage of RBC incorporation of the 54Fe given as a supplement compared with the 57Fe given in the formula (9.7 +/- 3.8% versus 7.8 +/- 3.1%, p = 0.02). The RBC 57Fe incorporation was closely correlated with the reticulocyte count (r = 0.80, p = 0.001), but not the serum ferritin or the Hb concentration. Approximately 68% of an i.v. dose of 58Fe was incorporated into RBCs. These findings indicate 1) iron is incorporated well into RBCs from preterm infant formula, with only a small increase in incorporation when given as a supplement, and 2) the reticulocyte count, but not the Hb concentration, is a good measure of RBC iron-incorporating capacity.

Birth Weight↗
PubMed1998

Early feeding, antenatal glucocorticoids, and human milk decrease intestinal permeability in preterm infants.

To determine the effects of age, feeding regimen, and antenatal glucocorticoids on intestinal permeability, preterm infants (n = 132) were stratified by gestational age and by diet (mothers' own milk versus preterm formula), and assigned randomly to one of four feeding regimens: early-continuous, early-bolus, standard-continuous, and standard-bolus. At 10, 28, and 50 d of age permeability was determined by measuring the ratio of lactulose/ mannitol in the urine after the two sugars were administered enterally for 30 h. The mean (+/-SE) birth weight and gestational age of the infants were 1044 +/- 13 g and 27 +/- 0.1 wk, respectively. Permeability changed as a function of age (p = 0.003). Early feeding was associated with a reduction in permeability at 10 d of age (p = 0.01). Antenatal steroid administration was associated with decreased permeability at 28 d of age (p = 0.017). The feeding of human milk (versus formula) was associated with decreased permeability at 28 d of age (p = 0.02). Continuous versus bolus feeding did not affect permeability.

Aging↗
PubMed1998

The role of human milk fortification for premature infants.

This article focuses on the current experience with the use of fortified milk in feeding premature infants. The use of fortified human milk provides the premature infant adequate growth, nutrient retention, and biochemical indices of nutritional status when fed at approximately 180 mL/kg/d compared with unfortified human milk. When compared with preterm formula, the feeding of fortified human milk may provide significant protection from infection and necrotizing enterocolitis. Neonatal centers should encourage the feeding of fortified milk for premature infants. Skin-to-skin contact is a reasonable method to enhance milk production while potentially facilitating the development of an enteromammary response.

Food, Formulated↗
PubMed1997

Oral feeding in low birth weight infants.

To gain a better understanding of the development of sucking behavior in low birth weight infants, the aims of this study were as follows: (1) to assess these infants' oral feeding performance when milk delivery was unrestricted, as routinely administered in nurseries, versus restricted when milk flow occurred only when the infant was sucking; (2) to determine whether the term sucking pattern of suction/ expression was necessary for feeding success; and (3) to identify clinical indicators of successful oral feeding. Infants (26 to 29 weeks of gestation) were evaluated at their first oral feeding and on achieving independent oral feeding. Bottle nipples were adapted to monitor suction and expression. To assess performance during a feeding, proficiency (percent volume transferred during the first 5 minutes of a feeding/total volume ordered), efficiency (volume transferred per unit time), and overall transfer (percent volume transferred) were calculated. Restricted milk flow enhanced all three parameters. Successful oral feeding did not require the term sucking pattern. Infants who demonstrated both a proficiency > or = 30% and efficiency > or = 1.5 ml/min at their first oral feeding were successful with that feeding and attained independent oral feeding at a significantly earlier postmenstrual age than their counterparts with lower proficiency, efficiency, or both. Thus a restricted milk flow facilitates oral feeding in infants younger than 30 weeks of gestation, the term sucking pattern is not necessary for successful oral feeding, and proficiency and efficiency together may be used as reliable indicators of early attainment of independent oral feeding in low birth weight infants.

Bottle Feeding↗
PubMed1997

Nutrient accretion in preterm infants fed formula with different protein:energy ratios.

BACKGROUND: Although standard formulas for preterm infants promote intrauterine rates of weight gain, fat deposition in preterm infants fed these formulas has been reported to be considerably higher than that in the fetus. We hypothesized that a preterm infant formula with a higher protein:energy (P:E) ratio would promote accretion rates of fat, fat-free mass, and minerals closer to those of the fetus. METHODS: As part of a larger study to determine whether accretion rates of fat and fat-free mass closer to those of the fetus can be achieved with a higher P:E ratio, we present a descriptive analysis of 72-h nutrient balance studies performed on a subset (n = 15/30) of the infants randomly assigned to be fed formula with a P:E ratio of either 3.2 g/100 kcal or 2.6 g/100 kcal. RESULTS: Despite the higher intake and net absorption of nitrogen by infants fed the higher P:E formula, there was no statistically significant difference in net nitrogen retention between groups. There also were no statistically significant differences between groups in digestible energy, metabolizable energy, energy expenditure, or energy storage. Thus, partitioning of stored energy as protein and fat did not differ between groups. The retention of calcium, phosphorus, sodium, potassium, copper, and zinc also did not differ between groups, and nitrogen intake did not affect mineral retention. CONCLUSIONS: In this study, formula for preterm infants with a P:E ratio of 3.2 g/100 kcal vs. 2.6 g/100 kcal provided no apparent benefit in terms of the proportion of fat to lean tissue accretion as determined from nutrient balance data.

Calcium↗
PubMed1997

Effects of long-term maternal intravenous magnesium sulfate therapy on neonatal calcium metabolism and bone mineral content.

A prospective study was designed to determine whether calcium homeostasis and bone mineral content were affected adversely in preterm infants born to mothers receiving long-term antenatal therapy with magnesium sulfate. Preterm infants born to mothers receiving long-term antenatal therapy with magnesium sulfate and requiring prolonged bed rest for preterm labor were compared with infants of mothers not receiving magnesium sulfate but in whom prolonged bed rest was also required. Serum magnesium, calcium, phosphorus, osteocalcin, and parathyroid hormone were measured in infants at 0, 24, 48, and 72 h after delivery. Bone mineral content of the distal radius was measured 1 week postnatally and at term-equivalent postmenstrual age. Maternal serum mineral status indices obtained near delivery and bone indices were compared with those of their infants. The clinical characteristics and morbidities of the infants were similar between groups. We observed significantly greater serum concentrations of magnesium, phosphorus, and osteocalcin during the 72 h after delivery and a lower serum calcium concentration which normalized by 72 h in preterm infants whose mothers were treated with magnesium sulfate compared with infants whose mothers did not receive magnesium sulfate. Both groups, however, had similar radius bone mineral content measurements and anthropometric indices after delivery. These data suggest that although preterm infants born to mothers treated with magnesium sulfate have delayed clearance of magnesium and phosphorus, they have a normalization of serum calcium by 72 h after delivery and no significant differences in bone mineral content after delivery compared with infants whose mothers do not receive magnesium sulfate.

Adult↗
PubMed1997

The effects of nutrient fortification and varying storage conditions on host defense properties of human milk.

OBJECTIVE: Data are scarce regarding the effects of nutrient fortification and storage on the immunoprotective properties of human milk. These effects are important considerations when feeding premature infants. We hypothesized that total bacterial colony counts (TBCC) and immunoglobulin A (IgA) concentration were not affected by the addition of fortifier even when tested under extreme storage conditions and that osmolality of fortified human milk does not increase with storage. METHODS: Ten frozen and five fresh milk samples from mothers of premature infants were divided into fortified and unfortified milk, and stored for 72 hours at either refrigerator or room temperature. Aliquots were obtained at 0 to 72 hours for TBCC, osmolality, and total IgA, and analyzed by repeated measures analysis of variance (ANOVA). RESULTS: Log10 TBCC in milk stored at refrigerator temperature for 0, 24, 48, and 72 hours were significantly greater in fortified vs unfortified milk; both increased similarly with storage. Osmolality was greater in fortified than unfortified milk; both increased by approximately 4% with storage. IgA concentration was not affected by fortification or storage. To simulate the usual nursery use of fortified human milk, a separate evaluation was performed. Fortified milk was stored at refrigerator temperature for 20 hours, warmed in a 40 degrees C laboratory incubator for 20 minutes, and placed in a 34 degrees C infant incubator for 4 hours. Samples for TBCC were obtained at 0, 20, and 24 hours and analyzed by repeated measures ANOVA. Log10 TBCC in fortified, refrigerated milk did not change over the 20-hour storage but increased during the simulated 4-hour usage. CONCLUSIONS: These findings may warrant consideration when using human milk in the neonatal nursery but support recommendations to use commercially fortified human milk within 24 hours.

Analysis of Variance↗
PubMed1996

Effect of carbohydrates on calcium absorption in premature infants.

Premature infants are susceptible to disease related to deficient dietary calcium intake. Studies in adults suggest carbohydrates can enhance calcium absorption. However, little is known about how carbohydrates affect calcium absorption in premature infants due to a lack of direct in vivo studies. We adapted the triple lumen perfusion method for use in premature infants to compare calcium absorption 36 mmol/L (1.44 g/L) in the absence and presence of either 70 g/L lactose or glucose polymers. 44Ca was added to determine endogenous calcium losses. Fourteen infants were studied (gestational age: 31 +/- 0.4 wk; study weight: 1590 +/- 105 g; mean +/- SEM). Calcium absorption from the glucose polymer solution was greater than that from the control and lactose solutions (0.17 +/- 0.05 mumol.min-1.cm-1 versus 0.04 +/- 0.04 and 0.008 +/- 0.045 mumol.min-1.cm-1, respectively). Calcium absorption correlated positively with water and carbohydrate absorption. The rate of carbohydrate absorption was greater from the glucose polymers than from the lactose solution (0.40 +/- 0.10 mg.min-1.cm-1 versus 0.22 +/- 0.06, respectively). Based upon 44Ca absorption, endogenous calcium loss appeared to account for less than 1% of total calcium flux. We conclude that glucose polymers, but not lactose, enhance calcium absorption in the premature infant, a fact that may be useful in formula design.

Calcium, Dietary↗
PubMed1996

Oral motor function in the neonate.

The information in this article illustrates the importance of evaluating oral motor function of the infant, not only as function of his or her own ability but also of external and maternal assistance. The proper development of maternal behavior as a contribution toward the development of sucking behavior may not be readily evident; however, awareness is growing that a close mother-infant interaction can positively affect the infant's ability to feed, as well as his or her psychosomatic development. As a consequence, it becomes essential that the integrity of the nursing dyad be protected. More often than not, caretakers have seen the latter break down when mother or infant becomes too involved. Studies focusing on maternal and neonatal non-nutritional attributes stress the importance of acquiring a better appreciation of the psychosomatic benefits that can be generated by the nursing dyad. With such understanding, interventions may be developed to enhance the expression of these factors to help safeguard mother-infant relationship during difficult times.

Bottle Feeding↗
PubMed1995

Postnatal attainment of intrauterine macromineral accretion rates in low birth weight infants fed fortified human milk.

HYPOTHESIS: Provision of more bioavailable mineral sources as human milk supplements enables very low birth weight (VLBW) infants to meet the intrauterine accretion rate for calcium and phosphorus. DESIGN: Comparison of currently formulated human milk fortifier with previous formulation. SETTING: Neonatal level II and III nurseries. PATIENTS: Twenty-six healthy, VLBW infants, whose mothers chose to breast-feed. INTERVENTIONS: We tested the effects of two formulations designed for VLBW infants as human milk supplements and differing primarily in their quantity and source of Ca, P, and magnesium. The study interval began with a milk intake of 100 ml.kg-1.day-1 and ended when a body weight reached 2.0 kg. MAIN OUTCOME MEASURES: Net absorption and retention of Ca, P, and Mg during a nutritional balance study conducted once during the study interval, growth during the entire study interval, and bone mineral content of the radius were measured at the beginning and end of the study interval. RESULTS: The newer Ca gluconate-glycerophosphate preparation (given to group CaGP) resulted in greater net absorption and retention of Ca and P (p < 0.01) than in infants given Ca phosphate (group CaTB). Mg retention was greater than (in group CaGP) or equivalent to (in group CaTB) the intrauterine accretion rate. Radius bone mineral content was significantly greater in group CaGP than in group CaTB (p < 0.001). Volumes of the fortified human milk preparation needed to meet the needs for gain in body weight were higher in group CaGP than in group CaTB (p < 0.001). CONCLUSIONS: Intrauterine accretion rates for Ca and P can be achieved when VLBW infants are fed human milk supplemented with Ca gluconate-glycerophosphate. Supplementation of human milk with Mg may not be indicated. In this study, greater intakes of Ca and P, and not improvements in bioavailability, result in improved net retention and bone mineral content of VLBW infants.

Absorption↗
PubMed1995

Suitability of human milk for the low-birthweight infant.

Information is emerging now that supports the use of human milk for low-birthweight (LBW) infants. The nutritional benefits, in terms of protein digestion, amino and fatty acid patterns, fat absorption, and lactose digestion are recognized. Gastrointestinal function may be enhanced with human milk feeding. Profound effects on host defense, including a reduction in the rates of neonatal infection and necrotizing enterocolitis, recently have been acknowledged. To enable the LBW infant to continue to receive a mother's own milk, attention needs to be focused on specific nutrient limitations. Calcium and phosphorus require supplementation. Protein and sodium supplements may be needed. Commercial formulations are available that enable the fortification of human milk. Approaches that facilitate the feeding of a mother's own milk should be adopted by neonatal units.

Amino Acids↗
PubMed1994

Parenteral nutrient needs of very low birth weight infants.

OBJECTIVE: To determine nitrogen and mineral needs in parenterally nourished very low birth weight infants. DESIGN: Prospective observational study. SETTING: Neonatal intensive care unit. PATIENTS: Twenty-four very low birth weight infants (< 1.2 kg) expected to receive parenteral nutrition (PN) exclusively for 3 weeks beginning 3 days after birth. INTERVENTIONS: Infants received PN solutions according to nursery protocol. Serial 24-hour balance studies were conducted twice weekly. Clinical therapies were tabulated. MAIN OUTCOME MEASURES: Intake, urinary excretion, and apparent retention of nitrogen, sodium, potassium, zinc, copper, calcium, phosphorus, and magnesium after initiation of PN. RESULTS: Although urinary K, Zn, Ca, P, and Mg excretion (but not N, Na, and Cu excretion) increased after PN therapy was begun, net nutrient retention increased significantly above baseline for all nutrients. Average weekly nutrient retention was significantly below intrauterine estimates of nutrient accretion for N, Na, Ca, P, and Cu; closely approximated estimates for Zn; and significantly exceeded those for K and Mg. Regression analysis was used to predict parenteral nutrient intakes that would support postnatal nutrient retentions equivalent to the intrauterine estimates. Postnatal therapy with dexamethasone affected N, P, and K excretion and retention. CONCLUSIONS: Soon after PN administration is begun, positive nutrient balance may be achieved early in the neonatal period. The magnitude of this effect remains uniform during PN administration. Adjustments in parenteral nutrient intake are needed to provide nutrient intakes sufficient to support postnatal retention at rates similar to those of intrauterine accretion. These data should be considered in the design of future studies to determine optimal PN needs of very low birth weight infants.

Calcium↗
PubMed1994

Hypercalciuria in premature infants receiving high mineral-containing diets.

We evaluated urinary calcium excretion in 21 premature infants fed either a formula containing high concentrations of calcium (Ca) and phosphorus (P) or human milk fortified with a commercially available human milk fortifier. Dual-tracer stable-isotope Ca absorption studies were performed on all infants. Urinary Ca excretion was not significantly related to Ca or P intake or true Ca absorption. The recovery of the orally administered tracer in the urine was used to evaluate the source of calciuria in study subjects. In almost all subjects, tissue-derived (Vbu), rather than diet-derived (Vou), Ca was the principal source of urinary Ca. Hypercalciuric subjects demonstrated greater Vbu and Vou than nonhypercalciuric subjects. Our data demonstrate that moderate hypercalciuria is common in premature infants whose diets are high in mineral content and that hypercalciuria is not related to inadequate mineral intake or Ca absorption but is related, instead, to losses of both tissue and dietary Ca.

Birth Weight↗