Effect of two amino acid solutions on leucine turnover in preterm infants

OBJECTIVE: To assess the effect of two different parenteral amino acid mixtures, Trophamine and Primene, on leucine turnover in preterm infants. METHOD: Leucine kinetics were measured with [5,5,5 D3]leucine tracer in 15 infants receiving Trophamine (group 'T') (mean birth weight 1,263 g) and 22 who received Primene (group 'P') (mean birth weight 1,336 g) during two study periods, within a few hours after birth but before introduction of parenteral amino acid solution, and again at postnatal day 7. The rate of appearance of leucine was calculated from the enrichment of alpha-ketoisocaproic acid in plasma. RESULTS: There were no significant differences in leucine turnover within a few hours after birth in the two groups. In the infants who received Primene leucine turnover on day 7 was significantly lower than in those who received Trophamine (269 +/- 43 vs. 335 +/- 27, p < 0.05). Despite a higher intake of leucine in the Trophamine group (108 +/- 10 vs. 77 +/- 8 micromol.kg(-1).h(-1)), leucine released from proteins at day 7 was higher in this group compared to Primene (227 +/- 27 vs. 192 +/- 42 micromol.kg(-1).h(-1)). CONCLUSIONS: Primene administration results in lower leucine released from proteins, an estimate of protein breakdown, than Trophamine in preterm infants. Increases in whole body leucine turnover in response to administration of i.v. amino acids is influenced by the composition of the amino acid mixture. The factors responsible for this difference remain to be elucidated.     

Evaluation of serum granulocyte colony stimulating factor levels in infants of preeclamptic mothers

In this study we aimed to evaluate the relationship between serum granulocyte colony stimulating factor (G-CSF) levels and absolute neutrophil counts (ANC) in infants of preeclamptic mothers. The study group consisted of 31 infants of preeclamptic mothers while the control group consisted of 24 gestational age-adjusted infants of normotensive mothers. G-CSF levels were determined by enzyme-linked immunosorbent assay (ELISA). The mean G-CSF level was 981.8 +/- 1682.5 (25.7-5924) pg/ml in the study group and 770.8 +/- 1779 (18-8526) pg/ml in control group (p > 0.05). There was no correlation between G-CSF levels and absolute or total neutrophil counts on the 1st, 2nd and 7th days in infants of preeclamptic mothers. There were positive correlations between G-CSF levels and ANC on the 1st and 7th days of life in infants of normotensive mothers. Neutropenia developed in 42.3% of the study group and in 21.7% of the control group on the 1st day of life (p > 0.05). On the 2nd day, neutropenia was observed in 61.5% of the study group and 26.1% of the control group (p = 0.013). Serum G-CSF levels were not low in neutropenic babies of preeclamptic mothers. In contrast, higher G-CSF levels in neutropenic infants suggest impaired G-CSF response in infants of preeclamptic mothers.     

Thyroid function tests in preterm infants born to preeclamptic mothers with placental insufficiency

OBJECTIVE: Since preeclampsia causes placental insufficiency, it can be hypothesized that it decreases placental passage of thyroxine (T4) from mother to infant and thus may deepen the transient hypothyroxinemia seen in preterm infants after birth. The aim of this study was to compare thyroid function tests of preterm infants born to preeclamptic mothers with placental insufficiency with preterm infants born to mothers without placental insufficiency. METHODS: Thirty-one preterm infants born to preeclamptic mothers with placental insufficiency were included in the study (group I) and 31 preterm infants born to mothers without placental insufficiency were included as the control group (group II). Thyroid hormone levels were assayed from blood samples obtained from the women before birth and thereafter from the infants at delivery (cord) and on the 1st, 3rd, 7th, and 21st days of life. RESULTS: Cord blood triiodothyronine (T3), free T3 (FT3) and free thyroxine (FT4) levels in group I were lower than in group II, whereas thyrotropin (TSH) and thyroxine binding globulin (TBG) levels were higher. No statistical difference in hormone levels studied at postnatal 1st, 3rd, 7th, and 21st day was found between the two groups. CONCLUSION: Low levels of thyroid hormones and high level of TSH in cord blood in premature infants born to preeclamptic mothers with placental insufficiency suggest intrauterine hypothyroidism. Increase in TSH and thyroid hormone concentrations after birth reveal that the hypothalamic-pituitary-thyroid axis is intact.     

Growth and neurodevelopment outcome of very low birth weight infants delivered by preeclamptic mothers

AIM: To investigate growth and neurodevelopment outcome of very low birth weight (VLBW) infants delivered by preeclamptic mothers. METHODS: A cohort including all VLBW infants delivered between December 2003 and May 2005 was followed up to 12 and 18 months corrected age (CA). Exclusion criteria: death before 1 year corrected age, major malformations, deafness and blindness. Weight, length and head circumference were plotted on NCHS curves. Bayley Scales were performed at 12 and 18 months CA. RESULTS: 40 infants in preeclamptic and 46 in control groups were studied. Birth weight and gestational age were 1148 g+/-236 and 1195 g+/-240, and 31.3 weeks+/-1 and 30.6 weeks+/-2 for preeclamptic and control groups, respectively. At 12 and 18 months, CA, weight for age (Z score) was significantly higher in control than in preeclamptic. PDI scores were higher in preeclamptic than in controls at 18 months CA. CONCLUSIONS: Catch-up of body weight did not occur in the first 18 months CA in preeclamptic infants. Neurodevelopment outcome was better in infants delivered by preeclamptic mothers than in controls at 18 months CA.     

Feeding problems in preterm infants of preeclamptic mothers

Aim: Maternal disease can cause prematurity and neonatal complications, notably feeding problems. To determine the relationship between maternal disease and the nature and severity of neonatal feeding problems, we compared feeding profiles, time to demand feeding and length of hospital stay between preterm infants of preeclamptic mothers, mothers with amniotic infection and mothers with other disease causing prematurity. Methods: The retrospective study used labour ward data collected from 2002 to 2005 in a tertiary university centre to analyse three groups of singletons born at <32 completed gestational weeks to mothers with preeclampsia (n = 61), amniotic infection (n = 55) and non‐preeclamptic non‐amniotic infection controls (n = 55). The groups were similar in gestational age, birthweight and sex ratio; all infants received enteral feeding according to departmental guidelines. Feeding profiles and enteral/oral nutrition were compared. Results: Feeding problems occurred in 46% of the preeclamptic group, 11% of the amniotic infection group and 13% of controls. Full oral demand feeding was established at 36 0/7 weeks postmenstrual age, 35 3/7 weeks (P = 0.03) and 35 2/7 weeks (P < 0.0001), respectively. Feeding problems were the main cause of delay (7–10 days) in hospital discharge in the preeclamptic group (P = 0.0002). Conclusions: Feeding problems are greater, and hospital stay longer, in preterm infants of preeclamptic mothers than in other preterm infants.     

Beta endorphin concentrations in human milk

BACKGROUND: The source and regulatory mechanisms that elevate beta-endorphin (beta-EP) approximately twofold higher than circulating plasma levels in the colostrum of lactating mothers are still unknown, and no studies have examined beta-EP availability previously during maturation phases of human milk. Therefore, the aim of this study was to determine whether concentrations of beta-EP vary over time between colostrum, transitional, and mature breast-milk and to evaluate whether this depends on the method of delivery. METHODS: Mothers of healthy full-term and pre-term newborn infants who planned to breast-feed their newborn infants were considered for this study. They were consecutively recruited in one of 3 groups of 14, according to delivery method: group 1, vaginal delivery at term (gestational age 40.2 +/- 0.3 weeks; birth weight, 3.48 +/- 0.09 kg); group 2, preterm vaginal delivery (gestational age, 35.6 +/- 0.3 weeks; birth weight, 2.49 +/- 0.08 kg); and group 3, at-term elective cesarean section (gestational age, 39.0 +/- 0.3 weeks; birth weight, 3.32 +/- 0.14 kg). Three consecutive breast milk samples were obtained on the fourth day after birth, before each mother's discharge, and thereafter on the 10th and 30th postpartum days, close to expression of the colostrum, transitional, and mature milk production phases, respectively, to test beta-EP concentrations (beta-Endorphin 125I RIA; INCSTAR Corporation, Stillwater, MN). Data are presented as mean +/- standard deviation. Statistical comparison of beta-EP concentration among the three lactating mother groups was performed using the Kruskal-Wallis nonparametric test. In addition, to test the hypothesis of a trend toward smaller values with time of beta-EP, the authors computed within each mother group a P value per trend (Kruskal-Wallis test) of beta-EP concentration averages on the 4th, 10th, and 30th days, respectively. Student's t test for independent samples was used for the analysis of the other data. The 0.05 significance level was used in the statistical analysis. All computations were made by computer. RESULTS: Colostrum beta-EP concentrations on the fourth postpartum day of group 1 and group 2 mothers who were delivered of a neonate vaginally, at term, or prematurely were significantly higher (P < 0.01) than colostrum levels of group 3 mothers who underwent cesarean section. Group 2 mothers who were delivered of a neonate vaginally and prematurely presented the highest beta-EP concentrations (P < 0.05), lasting until the transitional milk phase (10th day). No significant differences were found across all 3 groups of lactating mothers in mature milk (30th day) beta-EP concentrations. In addition, the beta-EP trend toward smaller values with time within each of the three groups on days 4, 10, and 30 was statistically significant (P < 0.01 per trend). CONCLUSIONS: It is hypothesized that elevated beta-EP concentrations in colostrum and transitional milk of mothers who were vaginally delivered of infants may contribute to postnatal fetal adaptation, to overcoming birth stress of natural labor and delivery, and at the same time to the postnatal development of several related biologic functions of breast-fed infants.     

Urinary excretion of prostacyclin metabolites in infants born after maternal preeclampsia or with birth asphyxia

Decreased fetoplacental prostacyclin (PGI2) production has been shown in preeclampsia, and increased pulmonary PGI2 synthesis has been demonstrated in experimental hypoxia. We measured the urinary excretion of the main metabolites of PGI2, 6-keto-prostaglandin F1 alpha (6-keto) and 2,3-dinor-6-keto-prostaglandin F1 alpha (2,3-dinor), during the first day of life in infants born to mothers with preeclampsia (n = 26), in infants with birth asphyxia (n = 12), and in control infants (n = 14). The mean excretion of 6-keto in control infants increased from 9.3 to 14.3 ng/h/1.73 m2 from 0-12 to 12-24 h of age, and a corresponding change from 3.5 to 7.0 ng/h/1.73 m2 was seen in 2,3-dinor excretion. In infants of preeclamptic mothers the excretion values at 0-12 and 12-24 h and the pattern of change were not significantly different from controls. In asphyxiated infants, the mean excretion values at 0-12 and 12-24 h of 6-keto (11.0 and 11.6 ng/h/1.73 m2) and 2,3-dinor (6.0 and 5.8 ng/h/1.73 m2) were not significantly different from control infants, but no increase was seen. We conclude that PGI2 production in infants of preeclamptic mothers is not impaired, but after perinatal asphyxia there is an altered pattern of PGI2 metabolite excretion, suggesting decreased production capacity.     

Maternal preeclampsia and jitteriness in preterm infants

AIM: To clarify the role of maternal preeclampsia in jitteriness in preterm infants. METHODS: Sixteen premature infants of preeclamptic mothers were observed for occurrence of jitteriness and were compared with 32 premature infants born to normotensive women. RESULTS: Jitteriness was present in a significantly higher percentage (75 vs 6%) and persisted longer (4.5 +/- 5.6 vs 1.5 +/- 0.7 days) in the preterm infants of preeclamptic mothers. CONCLUSIONS: Maternal preeclampsia could be included among the pathological factors that cause jitteriness in preterm babies.     

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目的研究早产儿甲状腺功能。方法将青岛大学医学院附属医院2004年10月至2005年10月收治的早产儿60例按胎龄分成两组小胎龄早产儿组(A组,胎龄<34周,n1=30),大胎龄早产儿组(B组,胎龄≥34周,n2=30)。对照组为我院出生的正常足月儿30例,应用放免法对3组新生儿生后第1,7天血清游离三碘甲腺原氨酸(FT3)、游离甲状腺素(FT4)、促甲状腺激素(TSH)水平进行测定。结果A、B组及对照组血清FT3、FT4生后1～7d呈下降趋势;对照组生后第1,7天血清FT3、FT4明显高于A、B组,B组明显高于A组;血清TSH在A、B及对照组生后呈下降过程;生后第1天对照组TSH>A组>B组;生后第7天,血清TSHA组高于B组和对照组,而B组与对照组差异无显著性。结论早产儿生后甲状腺功能有暂时性低下,胎龄越小,功能越低,生后应激反应持续时间越长。     

Maternal preeclampsia is associated with increased risk of necrotizing enterocolitis in preterm infants

Background

Necrotizing enterocolitis (NEC) is an important cause of mortality and morbidity in preterm infants.

Aims

To evaluate the effect of maternal preeclampsia on the development and severity of NEC in premature infants.

Study design

Prospective observational study in a tertiary neonatal intensive care unit.

Subjects

The preterm infants of ≤ 37 gestational age who were consecutively hospitalized were enrolled. The study group contained preterm infants born to a preeclamptic mother and the comparison group contained preterm infants born to a normotensive mother.

Outcome measures

The primary outcome was to determine the association between preeclampsia and NEC.

Results

A total of 88 infants had NEC diagnosis. The incidence of NEC in infants born to preeclamptic mothers (22.9%) was significantly higher compared with those born to normotensive mothers (14.6%). According to NEC stages, NEC was more advanced in preeclamptic mother infants. NEC developed significantly earlier in infants with NEC in the study group. The duration of NEC was also significantly longer in infants born to preeclamptic mothers. In multiple logistic regression model, preeclampsia was found to be predictive of NEC with an odds ratio of 1.74 (95% confidence interval 0.64–0.92).

Conclusions

Maternal preeclampsia may be an important risk factor for the development of NEC in premature infants as NEC incidence and severity of NEC were found to be significantly higher in premature infants born to preeclamptic mothers. The onset of NEC was significantly earlier and duration of NEC was longer in these infants.     

妊娠期高血压疾病对胎龄28~34周早产儿外周静脉血细胞计数的影响

目的 探讨母亲妊娠期高血压疾病（hypertensive disorders of pregnancy,HDP）对胎龄28~34周早产儿外周静脉血细胞计数的影响。 方法 选取2020年1~12月昆明医科大学第一附属医院儿科收治的母亲合并HDP的胎龄28~34周早产儿227例为研究组,另选取同期收治的母亲无HDP的胎龄28~34周早产儿227例为对照组。研究组根据母亲妊娠期血压分为妊娠期高血压亚组（75例）、轻度子痫前期亚组（81例）、重度子痫前期亚组（71例）;根据早产儿出生体重分为小于胎龄儿（small for gestational age,SGA）亚组（113例）及适于胎龄儿（appropriate for gestational age,AGA）亚组（114例）。比较研究组和对照组、研究组各亚组间早产儿生后第1天外周血细胞计数的差异。 结果 研究组患儿生后第1天外周静脉血白细胞（white blood cell,WBC）计数、中性粒细胞绝对计数（absolute neutrophil count,ANC）及血小板（platelet,PLT）计数均低于对照组（P<0.05）,白细胞减少症、中性粒细胞减少症发生率高于对照组（P<0.05）。亚组分析中,轻度子痫前期亚组、重度子痫前期亚组WBC计数、ANC、PLT计数均低于妊娠期高血压亚组（P<0.05）;SGA亚组WBC计数、ANC、PLT计数低于AGA亚组（P<0.05）。 结论 HDP可对早产儿外周静脉血细胞计数产生影响,这一影响在母亲子痫前期及SGA早产儿中更为显著。     

Effects of antenatal steroids on protein metabolism in preterm infants on the first day of life

OBJECTIVE: To analyze, in an existing cohort of infants, whether antenatal administered corticosteroids influence protein metabolism in preterm infants on the first day of life. Study design Three groups of infants were studied. The mothers of 25 infants had received 2 or more doses of corticosteroids, the mothers of 5 had received 1 dose, and there was no antenatal steroid exposure for 8 infants. Within a few hours after birth, a double-tracer leucine infusion was started by intravenous and intragastric routes and continued for 5 hours while the infants received only intravenous glucose. RESULTS: The plasma alpha-keto-isocaproic acid (KIC) enrichment (mol percent excess, MPE) from the intravenous tracer was not different between infants who reveived no antenatal steroids (8.58+/-1.64), 1 dose (7.60+/-0.78), and 2 or more doses (7.61+/-1.29). From the intragastric tracer, the plasma KIC enrichment from the intragastric tracer was different among the 3 groups, 7.62+/-2.35 for 0 doses, 5.78+/-0.85 for 1 dose, and 5.53+/-1.58 for 2 or more doses of antenatal steroids.Plasma KIC enrichment from the intravenous tracer was significantly higher than from the intragastric tracer in infants who received antenatal steroids, whereas there was no difference in infants who had not received antenatal steroids. Plasma leucine enrichment showed the same results. CONCLUSIONS: Antenatal corticosteroid administration to the fetus has no effect on whole-body leucine metabolism on the first day of life. However, it is associated with an increase in splanchnic leucine uptake at birth.     

早产儿血中胃动素水平对其胃肠道营养影响的研究

目的　探讨早产儿生后血中胃动素水平的变化及其对胃肠道营养的影响。方法　对72例早产儿应用放射免疫法监测其生后 12h内开奶前及第 3、7天空腹血中胃动素浓度 ;并以 16例正常足月新生儿作为对照。结果　 (1)早产儿组生后开奶前及第 3、7天空腹血中胃动素浓度分别为198 65± 5 8 42ng/L、2 48 83± 5 6 0 0ng/L、3 76 77± 13 9 46ng/L ,明显低于足月对照组的 3 0 0 3 3± 67 15ng/L、3 3 4 2 6± 83 81ng/L、5 10 64± 179 85ng/L(P <0 0 0 1及P <0 0 1) ;但随胎龄、日龄、奶量增加而升高 ,呈正相关 ;第 7天时已超过足月对照组生后开奶前水平。 (2 )喂养不耐受组早产儿生后空腹血中胃动素浓度均较喂养正常组低 ,尤以生后第 3天为显著 (P <0 0 5 ) ;(3 )早期喂养能改善早产儿胃动素水平和胃肠道动力 ,提高肠道喂养的耐受性。结论　早产儿消化道机能能适应胃肠道营养 ,早期喂养 (含微量喂养和非营养性吸吮 )可刺激其胃肠道出现迅速的适应性生长发育     

Cord transferrin and ferritin values in newborn infants at risk for prenatal uteroplacental insufficiency and chronic hypoxia

We measured cord transferrin and ferritin levels in 50 newborn infants with fetal conditions associated with either uteroplacental vascular insufficiency or chronic hypoxia. Sixteen small for gestational age infants, 21 infants of mothers with preeclampsia, and 13 symptomatic infants of diabetic mothers had significantly higher transferrin levels and lower ferritin levels and calculated iron stores than did asymptomatic gestational age-matched control infants without these conditions. Cord ferritin levels and calculated iron stores were significantly lower in the infants of diabetic mothers than in any other group of infants. Cord transferrin levels were inversely correlated with ferritin levels (r = -0.59, P less than 0.001) and were unrelated to transthyretin levels and birth weight in the high-risk infants, but were positively correlated with ferritin levels (r = 0.50, P less than 0.001), transthyretin levels (r = 0.65, P less than 0.001), and birth weight (r = 0.75, P less than 0.001) in the control infants. We conclude that cord transferrin levels do not reflect protein-energy status in newborn infants with prenatal histories suggesting uteroplacental insufficiency or chronic hypoxia, and that when associated with decreased cord ferritin levels, indicate possible impaired iron stores in these infants.     

Population-based case-control study of oral ketoconazole treatment for birth outcomes

The objective of the study presented here was to check the effect of oral ketoconazole treatment on fetal development. Ketoconazole has been given a teratogenic classification of C by the US Food and Drug Administration, but human controlled epidemiological studies of the treatment's effects have not been reported. The occurrence of ketoconazole use in the second to third months of gestation was compared between cases with congenital abnormalities and their matched controls in the large population-based data set of the Hungarian Case-Control Surveillance of Congenital Abnormalities, 1980-1996. Birth weight and gestational age were evaluated in control newborn infants born to mothers with or without ketoconazole treatment. The case group comprised 22,843 cases with congenital abnormalities, while the control group contained 38,151 newborn infants without any defects. Six infants (0.03%) and 12 controls (0.03%) had mothers who had received oral ketoconazole treatment (prevalence odds ratio: with 95% confidence interval: 0.8, 0.3-2.2). No group of infants with congenital abnormalities had mothers with a higher incidence of use of the drug. The mean gestational age was somewhat longer while birth weight was somewhat larger in controls with ketoconazole treated mothers. Our study failed to demonstrate a higher rate of congenital abnormalities in infants with mothers who had received oral ketoconazole treatment during pregnancy.     

The relationship between abdominal aortic intima-media thickness and lipid profile in neonates born to mothers with preeclampsia

Neonates born to mothers with preeclampsia are known to be associated with lipid alterations that might increase the risk for cardiovascular disease in adult life. The aim of this study was to investigate the effect of preeclampsia on lipid metabolism, aortic intimamedia thickness (aIMT) and subsequent atherogenic risk in newborn infants. Aortic intima-media thickness was measured in 60 neonates of mothers with preeclampsia (group I; 30 neonates of mothers with preeclampsia and group II; 30 neonates of mothers with severe preeclampsia) and 30 healthy neonates (group III). Maternal and cord serum lipid profiles were determined in all groups. Mean abdominal aIMT measurements were higher in the neonates born to mothers with preeclampsia (group I; 0.36 +/- 0.03 mm and group II; 0.36 +/- 0.04 mm) compared with the control group (group III; 0.33 +/- 0.03 mm, p = 0.006). Serum triglyceride levels were significantly higher in the neonates born to mothers with preeclampsia (group I; 39.2 +/- 42.0 mg/dl and group II; 39.5 +/- 56.5 mg/dl) compared with the control group (group III; 14.9 +/- 18.8 mg/dl, p = 0,039). Serum HDL cholesterol levels were significantly lower in the neonates born to mothers with preeclampsia (group I; 17.3 +/- 12.3 mg/dl and group II; 17.1 +/- 12.8 mg/dl) compared with the control group (group III; 27.6 +/- 13.0 mg/dl, p = 0.002). In conclusion; neonates of mothers with preeclampsia have significantly higher aIMT with lipid alterations. This may play a role in the pathogenesis of atherosclerosis in adult life.     

Superoxide dismutase and glutathione peroxidase content of human milk from mothers of premature and full-term infants during the first 3 months of lactation

BACKGROUND: Human milk contains various bioactive compounds including numerous immunologic factors, enzymes, growth factors, and hormones. However, the change during the course of lactation in many of these compounds has not been fully characterized. Therefore, the objective of the present study was to measure the activity of the enzymes superoxide dismutase (SOD; Enzyme Commission number [EC] 1.15.1.1) and glutathione peroxidase (SeGSHPx; EC 1.11.1.9) in human milk, to record changes in enzyme activity over time and to determine whether there are differences in activity between the milk of mothers of full-term (FT) and premature (PT) infants. METHODS: Nine samples were collected from each of 15 mothers (32 +/- 4 years of age; mean +/- standard deviation) of FT infants (gestational age, 40 +/- 1 weeks; birth weight, 3544 +/- 417 g) and 19 mothers (28 +/- 5 years of age) of healthy PT infants (gestational age, 29 +/- 4 weeks; birth weight, 1312 +/- 479 g). Samples were collected within a week of birth (+/- 1 day) and thereafter for 8 weeks, with a final collection at 12 weeks. RESULTS: During the 12-week study period, in both groups, total milliunits of GHSPx and SeGHSPx per milligram protein and SOD per per milligram protein increased, whereas protein content declined. SeGHSPx per milliliter milk was higher in the PT group at week 1 (92 +/- 30 mU/mL vs. 73 +/- 21 mU/mL), week 2 (93 +/- 28 mU/mL vs. 75 +/- 24 mU/mL), and week 7 (85 +/- 24 mU/mL vs. 68 +/- 22 mU/mL). The SOD activity per milliliter milk and milligram protein was higher throughout the entire study in the FT milk. CONCLUSIONS: Because mothers of PT infants may produce less milk than those of FT infants, PT infants may be at a disadvantage for antioxidant protection from these enzymes.     

Effects of early therapy with indomethacin on the manifestation of a persistent ductus arteriosus in extremely underweight premature infants

In a randomized study the effect of an early prophylactic indomethacin treatment on the incidence of the patent ductus arteriosus (PDA) in very low birth weight infants (VLBWI) and their postnatal course were investigated. 19 VLBWI (weight 1221 +/- 158 g, gestational age 28.2 +/- 1.3 weeks) received 0.2 mg/kg indomethacin 3 times p.o. in 12 h intervals beginning on the 3rd day of life. 22 VLBWI with comparable weight (1250 +/- 154 g, gestational age 28.4 +/- 1 weeks), mode of delivery and postnatal adaptation served as controls. PDA was diagnosed clinically and by a decreased ratio of the systolic time intervals preejection period (PEP)/left ventricular ejection time (LVET) less than 0.3. PDA were seen in 7 indomethacin treated VLBWI and in 13 newborns of the control group. A symptomatic PDA developed in 4 infants of the latter group only. The indomethacin group was characterized by an increased ratio PEP/LVET from day 3 to 5 as an evidence for a diminished ductal shunt. Their weight loss was 3% lower and they regained their birth weight 5 days earlier. Otherwise, there were no differences in mortality and morbidity. Despite the proven efficacy of an early indomethacin treatment its use is recommended only for infants with a high risk for a PDA substantiated by a low ratio PEP/LVET less than or equal to 0.24 at the 3rd day of life.     

Whole body protein turnover measured with 13C-leucine and energy expenditure in preterm infants

Our study was undertaken in preterm infants to examine the relationship of whole body protein kinetics with protein intake and energy expenditure. Leucine kinetics were determined in seven low birth wt preterm infants fed human milk or human milk enriched with protein (2.5 to 4.3 g protein/kg.d). The infants received a short (4-h) constant infusion of L-[1-13C]leucine and leucine turnover and oxidation were calculated from 13C-plasma leucine and expired 13CO2 enrichments measured by mass spectrometry. Energy expenditure was measured by indirect calorimetry. Nonoxidative leucine disposal (an estimate of protein synthesis) and leucine derived from protein (an estimate of protein breakdown) were, respectively, 2.98 +/- 0.82 and 2.06 +/- 0.74 mumol/kg.min. Whole body protein turnover and deposition, derived from leucine kinetics, were 8.22 +/- 2.31 and 2.17 +/- 0.50 g/kg.d, whereas energy expenditure was 56.3 kcal/kg.day. Protein turnover was correlated with protein intake but not with protein deposition. Energy expenditure was correlated with protein turnover, synthesis, and breakdown but not with protein deposition. These data are in agreement with the fact that protein deposition depends upon protein intake, but they also suggest that an elevated protein deposition is not necessarily the result of a rapid protein turnover or associated with an elevated energy expenditure.     

Acute effects of intravenous glutamine supplementation on protein metabolism in very low birth weight infants: a stable isotope study.

Although very low birth weight infants are subjected to severe stress and glutamine is now considered a conditionally essential amino acid that may attenuate stress-induced protein wasting in adults, current amino acid solutions designed for neonatal parenteral nutrition do not contain glutamine. To determine whether a short-term supplementation with i.v. glutamine would affect protein metabolism in very low birth weight infants, 13 preterm neonates (gestational age, 28-30 wk; birth weight, 820-1610 g) receiving parenteral nutrition supplying 1.5 g x kg(-1) x d(-1) amino acids and approximately 60 nonprotein kcal x kg(-1) x d(-1) were randomized to receive an i.v. supplement made of either 1) natural L-glutamine (0.5 g x kg(-1) x d(-1); glutamine group), or 2) an isonitrogenous glutamine-free amino acid mixture (control group), for 24 h starting on the third day of life. On the fourth day of life, they received a 2-h infusion of NaH(13)CO(3) to assess the recovery of (13)C in breath, immediately followed by a 3-h L-[1-(13)C]leucine infusion. Plasma ammonia did not differ between the groups. Glutamine supplementation was associated with 1) higher plasma glutamine (629 +/- 94 versus 503 +/- 83 microM, mean +/- SD; p < 0.05, one-tailed unpaired t test), 2) lower rates of leucine release from protein breakdown (-16%, p < 0.05) and leucine oxidation (-35%, p < 0.05), 3) a lower rate of nonoxidative leucine disposal, an index of protein synthesis (-20%, p < 0.05), and 4) no change in protein balance (nonoxidative leucine disposal - leucine release from protein breakdown, NS). We conclude that although parenteral glutamine failed to enhance rates of protein synthesis, glutamine may have an acute protein-sparing effect, as it suppressed leucine oxidation and protein breakdown, in parenterally fed very low birth weight infants.