Staffan Polberger

Growth of Very Low Birth Weight Infants on Varying Amounts of Human Milk Protein

ABSTRACT: In a double-blind, randomized study, 28 healthy, growing very low birth wt, appropriate-for-gestational- age infants were fed human milk, preferably mothers own, fortified daily with human milk protein and/or human milk fat. The infants entered the study when they were stable on complete enteral intakes of 170 ml/kgd (mean) age=19 d). The study lasted for a mean of 4 wk, Samples from all the milks were collected daily, and intakes of protein, fat, carbohydrates, energy, and electrolytes were calculated weekly during the whole study period. Protein intakes ranged from 1.7 to 3.9 g/kg/d, and energy intakes from 100 to 150 kcal/kg/d. Wt and length gain in the nonprotein-enriched groups were 15.6 ± 2.7 g/kg/d (mean ± SD) and 0.88 ± 0.17 cm/wk; the corresponding figures for the protein-enriched groups were 20.2 ± 2.1 g/ kg/d and 1.24 ± 0.14 cm/wk. There was a strong correlation between protein intake and growth in wt and length up to an intake of about 3 g/kg/d; more protein did not result in increased growth. The same was true for energy intake, with a maximal growth rate at an intake of about 120 kcal/ kg/d. A protein intake of more than 3 g/kg/d resulted in a growth rate equal to or higher than the estimated intrauterine growth rate. Some infants fed mature banked human milk alone had a poor growth. Sodium intake was low, ranging from 1.5 to 2.6 mmol/kg/d. No correlation was found between sodium intake and growth rates.

Individualized protein fortification of human milk for preterm infants: comparison of ultrafiltrated human milk protein and a bovine whey fortifier

BACKGROUND To improve the nutritional management of pre-term infants, a new individualized human milk fortification system based on presupplementation milk protein analyses was evaluated. METHODS In an open, prospective, randomized multicenter study, 32 healthy preterm infants (birth weights, 920-1750 g) were enrolled at a mean of 21 days of age (range, 9-36 days) when tolerating exclusive enteral feedings of 150 ml/kg per day. All infants were fed human milk and were randomly allocated to fortification with a bovine whey protein fortifier (n = 16) or ultrafiltrated human milk protein (n = 16). All human milk was analyzed for protein content before fortification with the goal of a daily protein intake of 3.5 g/kg. During the study period (mean, 24 days) daily aliquots of the fortified milk were obtained for subsequent analyses of the protein content. RESULTS Both fortifiers were well tolerated, and growth gain in weight, length, and head circumference, as well as final preprandial concentrations of serum urea, transthyretin, transferrin, and albumin were similar in both groups. The ultimate estimated protein intake was equivalent in both groups (mean 3.1+/-0.1 g/kg per day). Serum amino acid profiles were similar in both feeding groups, except for threonine (significantly higher in the bovine fortifier group) and proline and ornithine (significantly higher in the human milk protein group). CONCLUSIONS Protein analyses of the milk before individual fortification provides a new tool for an individualized feeding system of the preterm infant. The bovine whey protein fortifier attained biochemical and growth results similar to those found in infants fed human milk protein exclusively with the corresponding protein intakes.

Macromolecular Absorption in Preterm and Term Infants

ABSTRACT. Human o‐lactalbumin (α‐LA) has been used as a marker for measuring macromolecular absorption. The serum concentration of human α‐LA after a human milk feed has been studied in 32 healthy very low birthweight infants (VLBW), fed human milk (gestational age 26–32 weeks) and in 56 term, breast‐fed infants, age 3–140 days. At 31 weeks of gestation the serum concentration of human α‐LA was more than 10 times higher (mean value 3000 and median value 2101 μg/1 serum/1 human milk/kg body weight, n= 11) than in the term infants aged 3–30 days (mean value 257 and median value 152, n= 29). The serum concentration of o‐LA decreased with increasing maturity in the VLBW‐infants. At a postconceptional age of 37 weeks the values were similar (mean value 200 and median value 99, n= 8) to those found for term infants during the first month. In the term infants a decreasing absorption of α‐LA was found with increasing postnatal age.

Group B Streptococci at Delivery: High Count in Urine Increases Risk for Neonatal Colonization

Of 858 pregnant women studied in matched rectal, urethral and urine cultured specimens, 186 (22%) were found to be colonized by group B streptococci (GBS). GBS were detected significantly more often in rectal specimens (159) than in urethral specimens (108) or in urine specimens (64). This is supporting evidence for the gastrointestinal tract as the main habitat of GBS. Of 1786 women whose urine was sampled at delivery, GBS were isolated from 128 (7%), in 22 of whom (1% of the total) GBS were present in quantities greater than or equal to 10(4) colony forming units (cfu)/ml urine. Neonates born to women with greater than or equal to 10(4) cfu GBS/ml urine were apparently at greater risk for neonatal infection, as they were more commonly and more heavily colonized than were the newborns of women with lower quantities of GBS in urine, or if positive urethral or rectal specimens were considered. The incidence of preterm delivery or obstetric infection was not higher among women in whom GBS were isolated in specimens from any of the 3 sites; foetal distress was more common among their children, but not neonatal respiratory or infectious diseases of which the incidence was low and difficult to assess statistically.

Urinary and Serum Urea as Indicators of Protein Metabolism in Very Low Birthweight Infants Fed Varying Human Milk Protein Intakes

ABSTRACT. Urea concentrations in serum and urine were measured in 28 growing, very low birth weight, appropriate‐for‐gestational age infants fed varying human milk protein intakes (range 1.7 to 3.9 g/kg/day). We found a high correlation between serum urea values at the end of the study and mean protein intake (r3=0.85, p<0.001) and between urinary urea concentrations in eight‐hour urine collections and protein intake (r3=0.81, p<0.001). All serum and urine urea values were below 1.6 and 18 mmol/l, respectively, at protein intakes less than 3 g/kg/day. Higher protein intakes caused higher serum and urinary urea concentrations. We also found a strong correlation between the individual serum and urinary urea values at the end of the study (r3=0.90, p<0.001). The presented data are consistent with the growth data previously reported and indicate that inadequate or excessive protein intakes can be detected by measurement of urea concentrations in serum and/or urine. If urine urea samples alone can be used for estimating optimal protein intake, painful blood sampling procedures could be obviated.

Simple and rapid macronutrient analysis of human milk for individualized fortification: basis for improved nutritional management of very-low-birth-weight infants?

Feeding human milk exclusively to the very-low-birth-weight infant may lead to insufficient intakes of protein and energy. Although the milk is therefore often supplemented with protein and additional calories, there is usually no prior information on its macronutrient composition. If such data were available, it would be possible to individualize the fortification of the milk. To find simple, rapid, and inexpensive methods of enriching it, we evaluated existing macronutrient assays of human milk. Thirty frozen samples of early human milk (3-20 days of lactation) were analyzed for contents of protein (Kjeldahl, Lowry, and Bio-Rad protein assays), fat (Folch, total lipids assay, and creamatocrit), and carbohydrates (lactose and orcinol assays). The methods were modified to minimize cost and time. From these data, we find it appropriate to recommend the use of the Lowry (or, alternatively, the Bio-Rad) protein assay, the total lipids assay, and the orcinol carbohydrate assay for reasonably accurate determinations of the protein and energy contents of human milk. Because the variation in the carbohydrate content of human milk is very small, a more simple alternative approach would be to include only an average carbohydrate value for an estimate of energy content. These low-cost methods can be used in all laboratories affiliated to neonatal units taking care of preterm infants. Such individualized fortification should serve to further improve the nutritional management of very-low-birth-weight infants.

Hip Joint Instability in Breech Pregnancy

ABSTRACT. 222 consecutive fetuses found by ultrasound to be in breech presentation in the 33rd gestational week were followed with repeated examinations in weeks 35 and 38. Ninety‐one of these fetuses persisted in breech presentation until delivery, while cephalic version occurred in 131. The frequency of hip joint instability was 21% in the breech delivered group and 1.5% in the vertex delivered group. The position of the fetal legs was established at each ultrasound examination. The intrauterine fetal attitude was classified as extended when the fetuses had extended knees and maximally flexed hips at all ultrasound examinations. This occurred in 30 breech delivered fetuses, 47% of which developed hip joint instability. Only 8% of the breech born infants with flexed legs in utero developed hip joint instability. It is concluded that instability of the hip joint is a consequence of the intrauterine attitude, rather than of the breech delivery per se.

A Prospective Study of Rotavirus Infections in Neonatal and Maternity Wards

ABSTRACT. The occurrence and symptomatology of rotavirus infections was studied at three maternity wards and one neonatal unit. Rotavirus was identified in 12.7% of 553 infants and 1.3% of 542 mothers at the maternity wards. Infections were more frequent in a mixed obstetric/ gynecology ward than in the pure obstetric wards. Only 10% of the infants had symptomatic infections. Subgroups of rotavirus was determined in 41 infants: 22 of subgroup I and 19 of subgroup II, which is the subgroup accounting for the majority of childhood gastroenteritis. Rotavirus was found in faecal samples from 37% of the infants at the neonatal unit during an eight‐month survey. A seasonal variation with most infections during colder months was seen. Subgroup determination was possible in 29 cases, 14 subgroup I and 15 subgroup II. Fifteen per cent of the infections demonstrated diarrheal symptoms. No significant difference among other clinical data registered was seen among rotavirus infected compared to the non‐infected infants. We conclude that neonatal rotavirus infections occur as an endemic infection at our maternity wards possibly combined with infections due to external sources of virus in mixed wards and neonatal units

Tolerance to early human milk feeding is not compromised by indomethacin in preterm infants with persistent ductus arteriosus.

Aim: Early human milk feeding is beneficial for gut and brain development. Persistent ductus arteriosus (PDA) and indomethacin may compromise enteral function in preterm infants. For many years enteral milk feedings have continued in preterm infants receiving indomethacin for PDA. The aim of this study was to investigate whether this strategy is efficient in terms of risks and tolerance to early enteral feeding. Methods: This retrospective study included 64 inborn infants of <29 wk gestational age (GA), 32 infants who received indomethacin for symptomatic PDA (case infants) and 32 matched controls. Case infants had a mean (SD) GA of 26.3 wk (1.3) and body weight 839 g (203) versus controls GA 26.4 wk (1.2) and body weight 896 g (213) (p= 0.82 and 0.27, respectively). Case infants had higher respiratory morbidity; 90.6% versus 50% of controls needed mechanical ventilation (p= 0.000). Results: Case infants received human milk from a median (range) age of 4.0 h (1.5‐27.5), and controls from 5.3 h (2.0‐38.0) (p= 0.092). The first dose of indomethacin was given at a mean age of 1.7 d (1.0). There were no differences between the two groups in feeding volumes or gastric residuals on days 1 to 7. Mean (SD) feeding volume on day 7 was 64 ml/kg (31) in case infants and 76 ml/kg (30) in controls (p= 0.23). Four infants developed necrotizing enterocolitis: two case infants and two controls (p= 1.00).

Perinatal Outcome in Growth Retarded Pregnancies Dated by Ultrasound

To analyse the incidence of fetal growth retardation and its impact on perinatal mortality and neonatal morbidity, pregnancies complicated by intra‐uterine growth retardation (IUGR) were compared with matched non‐IUGR pregnancies. The IUGR group included all infants born in the city of Malmö during the study period and having a birthweight of 2 standard deviations or more below the mean birthweight for gestational age. The gestational age of all pregnancies was assessed with ultrasound in the first half of pregnancy. The IUGR fetuses were more vulnerable during delivery, and emergency cesarean section due to imminent fetal asphyxia was performed more frequently, but Apgar scores were similar in both groups. The frequency of respiratory disorders was lower in the IUGR group than in the non‐IUGR group when corticosteroid‐treated pregnancies were excluded. The IUGR group required slightly longer care on the neonatal ward than the non‐IUGR group, but not more intervention. The IUGR group as a whole had an unexpectedly low neonatal complication rate, such complications as did occur being related to preterm birth rather than to growth retardation.