Activities of trypsin and lipase in duodenal aspirates of preterm infants: influence of dietary protein and fat composition.

The influence of three different feeding regimens on the activities of pancreatic lipase and trypsin in duodenal aspirates and on fecal nitrogen and fat excretion was studied in 35 healthy preterm infants after a 2-wk feeding period. Eleven infants received a standard preterm formula (without long-chain polyunsaturated fatty acids), 12 were fed with an experimental formula that only differed from the standard formula in fat blend composition (with long-chain polyunsaturated fatty acids), and 12 infants received human milk fortified with protein and energy to have similar nitrogen and energy contents as the two formulas. There were no significant differences in duodenal trypsin activities among the groups. In the group fed the standard formula, lipase activity was significantly lower than in the group fed the experimental formula (standard formula group: 8.4 +/- 3.5 kU/L; experimental formula group: 13.8 +/- 4.8 kU/L; P < 0.05) but there was no significant difference between the experimental formula group and the human milk group (15.1 +/- 4.2 kU/L). Fecal nitrogen as well as fat excretion were similar in the three feeding groups. The data suggest that dietary fat composition can influence the postnatal development of duodenal lipase activity in preterm infants.

Essential fatty acid status in premature newborns fed by nasoduodenal technique.

The fatty acid composition of plasma phospholipids and the triene (20:3, n=9) to tetraene (20:4, n=6) ratio in the same lipid fraction have been determined, as indices of the essential fatty acid status, in a group of 22 healthy premature newborns fed by the nasoduodenal technique. Determinations have been carried out on the first and fifth day of life for all 22 newborns, and also on the tenth and 30th day of life for 12 of them. The normal plasma levels of essential fatty acids obtained indicate a satisfactory utilization of dietary essential fatty acids under these unusual nutritional conditions.

Taurine and cholesterol supplementation in the term infant: responses of growth and metabolism.

The effects of taurine and of cholesterol supplementation to a whey-protein-predominant formula fed ad libitum on the growth and biochemical responses of term infants were studied. The responses of these infants were compared to those of infants fed formula without a supplement and infants that were breastfed. These infants were followed for 12 weeks. No effect of cholesterol was observed on any of the measurements and no effect of taurine was observed on any of the biochemical measures with the exception that taurine concentrations in plasma and urine (reduced in infants fed formula alone) were corrected to concentrations observed in breastfed infants. Taurine supplementation had no effect on the rate of weight gain or on linear growth over the complete course of the study. Thus, taurine supplementation of formulas returns plasma and urine concentrations of this amino acid to those found in human milk-fed infants. However, these data indicate that the supplementation of formulas with taurine has no benefit with respect to growth.

Management of extremely low-birth-weight infants.

Better health care of women during pregnancy and delivery, improvement in neonatal intensive therapy and technology have led to a decrease in neonatal mortality and morbidity and to lower limits of birth weight and gestational age for survival. This paper refers to the management protocol used in the Department of Perinatal Pathology of the Provincial Maternity Hospital of Milan for extremely low-birth-weight (ELBW) infants (birth weight < 1000 g). In this hospital, all newborn infants presenting evidence of life, irrespective of birth weight and gestational age, are resuscitated and transferred to the Neonatal Intensive Care Unit (NICU) for clinical management. After the introduction of this protocol the mortality rate of ELBW infants dropped from 71.4% in 1977-78 to 48% in 1987-88. In a group of 72 ELBW infants with a mean birth weight of 850 g and a mean gestational age of 27 weeks, 80% presented a normal outcome, 12% presented a mild neurological impairment and 8% were affected by severe cerebral palsy at the age of two years. The intact survival of a newborn infant of 450 g at birth is also reported.

Adult outcomes of three newborns with a combined weight of 1100 grams.

OBJECTIVE: To present the short- and long-term (20 years) growth and developmental outcomes of four micropremies (birth weight of less than 500 grams). METHOD: Retrospective review of medical records and prospective assessment/interview with patients and their families. RESULTS: One infant was lost at long-term follow-up. The other three showed a quite satisfactory health status and life style in early adulthood. CONCLUSIONS: Despite extreme low birth weight (less than 500 grams) normal outcomes are possible. In the case of micropremies, gestational age appears to be of greater importance than birth weight as well as female gender in the decision-making process regarding initiation of resuscitation.

Constraints of intensive care units and follow-up studies in prematures.

This paper reviews the main known causes of deafness in newborns at risk. Some of them, like infections, anoxia, prematurity, etc. can be classified as 'clinical factors'. Others, like the ototoxicity of some antibiotics and the noise of the life-supporting equipment, are described in the paragraph on the 'constraints of intensive care'. Finally, the possible potentiating effect that some of the above mentioned factors may have on each other is mentioned in the paragraph entitled 'combined effects'. The need of accurate follow-up studies of neonatal intensive care unit (NICU) babies treated in different ways is stressed in the last paragraph.

Milk protein intake in the term infant. I. Metabolic responses and effects on growth.

Thirty healthy term infants were studied during the three first months of life. The infants were divided into three feeding groups consisting of 10 infants in each. The feeding regimens were: human milk by breast feeding, a formula (F-I) containing 1.2 g/100 ml of protein and a control formula (F-II) containing 1.6 g protein/100 ml. Both formulas were whey predominant and isocaloric. Protein intake was significantly higher with formula F-II when compared to the human milk group and to formula F-I. No significant differences with respect to weight, length and head circumference were found among the groups, but the rate of growth between 2 to 12 weeks was higher in the control formula (F-II) group. Serum albumin concentrations were normal and similar in all feeding groups. Blood urea nitrogen and urine total nitrogen concentration was significantly lower in the low protein formula I group when compared to the control formula II. After the fourth week of life the low protein formula infants had similar blood urea nitrogen and urine nitrogen concentrations as those of the breast-fed infants. The results indicate that current formulas in use provide excessive protein intakes after the first months of life.

[Effect of the amino acid content of breast milk supplements on the amino acid profile in the plasma of newborn infants: human albumin in comparison with Eoprotin]. / Einfluss der Aminosäurezusammensetzung von Frauenmilchsupplementen auf das Aminosäureprofil im Plasma Frühgeborener: Humanalbumin im Vergleich mit Eoprotin.

The influence of amino acid composition of two human milk fortifiers (Eoprotin, Milupa AG, Germany, and human albumin) on plasma amino acid profiles was studied in 28 preterm infants after a 14-day feeding period. The concentrations of total essential amino acids increased in both feeding groups significantly if compared to the period without supplementation; only the concentrations of methionine and phenylalanine in the eoprotin group and those of threonine, methionine and isoleucine in the human albumin group did not increase significantly. However, only the concentrations of isoleucine (Eoprotin: 79 +/- 19 mumol/l; human albumin: 45 +/- 20 mumol/l, p < 0.001) and methionine (Eoprotin: 26 +/- 10 mumol/l, human albumin: 16 +/- 10 mumol/l, p = 0.014) were significantly different between the two feeding groups. There was a significant correlation between the differences in the serum concentrations and the ones of each essential amino acid concentration in the fortifiers (r = 0.951). The results indicate that the amino acid composition of human milk fortifiers must be taken into consideration to achieve optimal nutritional management of preterm infants.

Bile acid concentrations in serum and duodenal aspirates of healthy preterm infants: effects of gestational and postnatal age.

In 41 healthy human-milk-fed preterm infants the preprandial total bile acid (BA) concentrations in serum and duodenal juice were simultaneous measured during the first 60 days of life. The infants were subdivided into four groups according to their gestational age: 6 infants with a gestational age of 27 and 28 weeks, 7 infants with a gestational age of 29 and 30 weeks, 21 infants with a gestational age of 31 and 32 weeks and 7 infants with a gestational age of 33 and 34 weeks. The BA levels were enzymatically determined using 3-alpha-hydroxysteroid dehydrogenase. In the duodenal juice, cholic acid (CA), chenodeoxycholic acid (CDCA), deoxycholic acid and lithocholic acid were separately quantified by thin-layer chromatography. During the first month of life, the serum BA concentrations increased significantly with postnatal age (p < 0.01) but remained nearly constant during the second month of life. In the duodenal aspirates, the BA concentrations increased continuously up to the end of the observations period (p < 0.001). In the duodenal aspirates, the CA/CDCA ratio was high immediately after birth and decreased significantly with increasing postnatal age (p < 0.001). During the first weeks of life, the BA levels were preferentially conjugated with taurine, but in spite of the taurine-rich diet during the whole observation period the taurine/glycine ratio decreased with postnatal age (p < 0.001). In all samples of duodenal juice, the sum of primary BA was > 98% of total 3-alpha-hydroxy-BA. These data indicate that the establishment of an intestinal microbial flora necessary for intestinal BA transformation and the development of the enterohepatic BA circulation lasts some months of postnatal life. The serum BA concentration reflects hepatic synthesis, intestinal absorption, renal excretion and hepatocellular transport into bile in a very complex way which may limit the diagnostic value of serum BA during this time. Additionally, a duodenal BA concentration below 4 mmol/l, as found in this study during the first 2 weeks of life, may be of clinical importance due to its possible effects on fat absorption.

Milk protein intake in the term infant. II. Effects on plasma amino acid concentrations.

The response of plasma amino acids to two bovine protein formulas with different protein content (1.6 and 1.2 g/100 ml containing 60% whey proteins and 40% caseins) was measured in term infants. These two groups of infants were compared with a group of infants that were breast-fed; all infants were fed ad libitum. Concentrations of threonine, valine and total branched chain amino acids reflected the amount of protein provided. Thus, the concentrations were higher in the higher protein formula infants from the second week of the study. In the low protein formula infants these amino acids were lower but differed from the infants on breast milk at eight and twelve weeks. Concentration of taurine was lower in the formula fed infants than they were in breast-fed infants at the end of the study. The valine/glycine ratio in the low protein formula group was lower than in the breast-fed group for the first four weeks of the study. After this time it was equal to that of the breast-fed group. These differences in plasma amino acid concentrations give further evidence that formulas now in common use for term infants provide a protein intake in excess of protein requirements after the first months of life.

Limited fat digestion in infants with bronchopulmonary dysplasia.

In 10 hyaline membrane disease patients with development of bronchopulmonary dysplasia, 16 hyaline membrane disease patients without development of bronchopulmonary dysplasia, and 12 very-low-birthweight infants without major medical problems, we measured the lipase and trypsin activity as well as the bile acids concentrations in preprandially aspirated duodenal juice. In addition, fat and nitrogen balances were performed during the 5th and 6th weeks of postnatal life. The mean duodenal lipase activity in the patients with bronchopulmonary dysplasia was significantly lower than those of the patients without bronchopulmonary dysplasia (4.41 +/- 3.0 versus 9.95 +/- 3.0 U/ml, p < 0.05) and of the controls (19.94 +/- 6.8 U/ml). The mean total bile acid concentration was below the critical micellar concentration of 4 mmol/L only in the patients with bronchopulmonary dysplasia. The fecal fat excretion rate in the patients with bronchopulmonary dysplasia was significantly higher than in the patients without bronchopulmonary dysplasia (21.4 +/- 4.6% versus 11.3 +/- 3.4% of intake, p < 0.01) as well as that of the controls (7.9 +/- 2.8% of intake). The serum urea concentrations were similar in the patients without bronchopulmonary dysplasia and in the controls (1.97 +/- 0.6 and 1.89 +/- 0.4 mmol/L, respectively) but significantly higher in the patients with bronchopulmonary dysplasia (2.54 +/- 0.5 mmol/L). The lowest weight gain was found in the patients with bronchopulmonary dysplasia (8.2 +/- 4.7 g/kg/day). It was significantly lower than one of the patients without bronchopulmonary dysplasia or the controls (13.5 +/- 4.0 and 16.2 +/- 3.7 g/kg/day, respectively). The data indicate that patients who develop bronchopulmonary dysplasia have a limited fat absorption, which may help to explain the inadequate weight gain.

Nasoduodenal feeding in high risk newborns.

Recent reports indicate that nasoduodenal feeding is a suitable technique for high risk newborns, in particular those with a low birth weight. In the period between February 1975 and June 1976, 100 high risk newborns, divided into four cohorts on the basis of birth weight in 500 g divisions, were fed by nasoduodenal tube. The effect of nasoduodenal feeding has been measured in several ways, but particularly consideration has been given to weight gain, its caloric cost, the mortality rates observed in the Unit before and after the introduction of this nutritional regime and complications. The use of nasoduodenal feeding abolished the physiological loss of weight which normally occurs during the first week of life and was associated with a subsequent rate of weight gain equal to or better than that observed in infants fed by other routes. The mean caloric intake was greater in smaller infants than in larger ones and it was accompanied by a steady decrease in weight gain per unit of caloric intake with increasing birth weight. In 1974 the overall mortality rate in the Unit was 18% and in 1975 following the introduction of nasoduodenal feeding fell to 11.4%. No serious complications were observed associated with nasoduodenal feeding. The conclusion is that this form of feeding is particularly suitable for infants with a birth weight of 1 500 g or less.

[Feeding the newborn infant with respiratory insufficiency]. / Come alimentare il neonato con insufficienza respiratoria.

In feeding the newborn with respiratory distress it must be considered the increased metabolic and water requirements. To feed this newborn we can choose among total parenteral nutrition, total enteral nutrition and a combination of the two methods. Data concerning 98 newborns with respiratory distress, admitted into Neonatal Intensive Care Unit of the Provincial Maternity Hospital of Milan, are described.

[Mineral bone content in full-term infants. Effect of anthropometric characteristics]. / Il contenuto minerale osseo nei neonati a termine. Influenza delle caratteristiche antropometriche.

The clinical importance of the measurement of bone mineral content (BMC) in fullterm infants by photon absorptiometry relies on a comparatively narrow normative range that is necessary requisite to interpret the data from a single child. In the attempt to reduce the artifactual scattering of data, it was undertaken a normative study to control all variables that might affect BMC at birth. Thus, growth parameters and birth season (as an index of maternal vit. D status) were related to BMC, Bone Width (BW) and the considered growth parameters did not show any significant difference related to sex and birth season. Thus, all data were analyzed together. It appears that BMC at birth in fullterm infants averaged 92.2 +/- 14.6 mg/cm. BMC did not correlate with skeletal length, crown length and gestational age in the considered range. Conversely, significant correlation were found between BMC and BW and between BMC and body weight. We conclude that: a) birth season and sex do not affect bone mineralization in fullterm infants, b) any comparison among BMC should be established within populations homogeneous for weight and BW.

Protein quality of human milk fortifier in low birth weight infants: effects on growth and plasma amino acid profiles.

Serum preprandial essential amino acid, urea and prealbumin concentrations, and growth rates were studied in appropriate for gestational age low birth weight infants fed one of three regimens: (1) human milk enriched with human milk protein (n = 17); (2) bovine whey protein hydrolysate (n = 18; and (3) a mixture of bovine proteins, peptides and amino acids designed to have an amino acid composition close to that of human milk proteins (n = 18). Energy and nitrogen intakes were similar in all groups. Growth rates and gross metabolic responses did not differ between the feeding groups. There were also no differences in the amino acid profiles between those infants fed human milk protein fortifier and mixed bovine protein fortifier. Infants fed the whey fortifier had significantly higher threonine concentrations in comparison to those fed exclusively human milk protein (287 +/- 63 mumol/l vs 168 +/- 26 mumol/l) whereas the levels of some other essential amino acids (i.e. valine, leucine, lysine, histidine, phenylalanine and tryptophan) were lower. The results indicate that growth rates and gross metabolic indices do not depend on the protein quality of human milk fortifiers. However, the addition of well balanced mixtures of bovine proteins to human milk results in amino acid profiles similar to those observed in LBW infants fed similar amounts of human milk proteins.

Fetal lung maturity evaluation with fluorescence polarization of the amniotic fluid.

Fluorescence polarization of the amniotic fluid from 39 high risk pregnancies requiring preterm delivery was measured in order to assess the maturity of the fetal lung. The study population included 15 cases of intrauterine growth retardation, ten maternal hypertension, five maternal Hodgkin's disease, three placenta previa, two fetal malformation, two polyamnios, one untreated diabetes, one maternal nephropathy. All patients underwent a single amniocentesis before deciding whether to deliver a preterm baby and FP of the amniotic fluid was done within two hours from amniocentesis. In five cases this was > 0.311, the cut-off limit taken as an indicator of fetal pulmonary status, and three of these developed respiratory distress syndrome. In 34 cases FP values were < or = 0.311; in spite of the apparent lung maturity two of these newborns developed respiratory distress syndrome. On the basis of these results the FP sensitivity was calculated as 60%, specificity 94% and the overall accuracy 90%.

Growth and metabolic responses in low-birth-weight infants fed human milk fortified with human milk protein or with a bovine milk protein preparation.

Unfortified human milk does not normally provide enough protein to secure maximal growth in low-body-weight (LBW) infants. Due to the practical difficulties in obtaining human milk protein (HMP), a bovine milk protein preparation (BMP) was designed by computer calculation to contain as close as possible the amino acid composition of the nutritionally available human milk proteins. Twenty-one AGA, LBW infants (BW of 1,180 to 1,600 g, GA of 27 to 33 weeks) were randomly assigned to be fed HM enriched either with HMP (9 infants) or BMP (12 infants). When full volume intake (170 ml/kg/day) was reached, the protein intakes were 3.6 +/- 0.5 and 3.3 +/- 0.3 g/kg/day, respectively, in the two diet groups. During the study period of 24 days, the infants achieved intrauterine or better weight gains: 32.9 +/- 3.3 g/day (17.7 +/- 1.9 g/kg/day) in the HMP group and 34.7 +/- 7.3 g/day (18.3 +/- 3.5 g/kg/day) in the BMP group. Serum urea nitrogen, acid-base status, and albumin values were normal and similar in both groups of infants. Plasma concentrations of total essential and total amino acids at the end of the study were 3,999 and 1,539 mumol/L and 3,899 and 1,422 mumol/L in the HMP and the BMP groups, respectively. The concentrations of all individual plasma amino acids were similar in both feeding groups. These results show that feeding human milk fortified with a modified bovine milk protein preparation produces satisfactory growth and a plasma amino acid profile similar to that found in LBW infants fed exclusively human milk protein at similar intakes.