A prospective study of intrapulmonary fat accumulation in the newborn lung following intralipid infusion

In order to assess the safety and stability of a parenteral fat emulsion (Intralipid) in total parenteral nutrition (TPN), 29 infants were infused Vamin glucose and Dextrose electrolyte solution as well as one of two isocaloric regimens; either 25% Dextrose (Group I) or 10% Intralipid (Group II). Regular biochemical monitoring was performed in all cases and no infants became lipaemic nor developed abnormally high levels of total free fatty acid. Eight infants died and only those who had received fat emulsion had lipid staining material distending the pulmonary vessels. One infant having low infusion rates of Intralipid had massive fat accumulation in the lungs, but biochemistry during life had been normal. We speculate that in ill infants the emulsion becomes less stable and agglomeration of fat particles occurs which are then fully filtered out by the lungs before metabolism of the exogenous fat can occur.     

A Prospective Study of Intrapulmonary Fat Accumulation in the Newborn Lung Following Intralipid Infusion

In order to assess the safety and stability of a parenteral fat emulsion (Intralipid⁸) in total parenteral nutrition (TPN), 29 infants were infused Vamin glucose and Dextrose electrolyte solution as well as one of two isocaloric regimens; either 25 % Dextrose (Group I) or 10 % Intralipid (Group II). Regular biochemical monitoring was performed in all cases and no infants became lipaemic nor developed abnormally high levels of total free fatty acid. Eight infants died and only those who had received fat emulsion had lipid staining material distending the pulmonary vessels. One infant having low infusion rates of Intralipid had massive fat accumulation in the lungs, but biochemistry during life had been normal. We speculate that in ill infants the emulsion becomes less stable and agglomeration of fat particles occurs which are then fully filtered out by the lungs before metabolism of the exogenous fat can occur.     

Clinical Pharmacology of Gentamicin in the Newborn Infant

Newborn infants with suspected bacterial infection were treated with intramuscular gentamicin. Serum levels of the drug were measured 1 hour after the first dose, immediately before the second dose, and immediately before and 1 hour after a dose given on the third day.On a low dosage regimen (1 mg/kg every 8 hours) 9 of 17 infants had serum gentamicin levels below the required minimum level of 1 μg/ml immediately before the second dose, and 5 of 19 infants had similarly low levels on the third day. On a high dosage regimen (3 mg/kg initially, then 2 mg/kg every 8 hours) 2 of 10 infants had preinjection serum gentamicin levels below 1 μg/ml on the first day, and 3 out of 16 had similar levels on the third day. The mean (± SE) serum gentamicin level on the high dosage regimen was 5·0 ± 0·5 μg/ml 1 hour after the first injection, 1·9 ± 0·4 μg/ml just before the second injection, and on the third day 1·9 ± 0·3 μg/ml just before an injection and 5·1 ± 0·5 μg/ml 1 hour after injection. The highest serum gentamicin level recorded in any of the 40 infants studied was 8·2 μg/ml.On the first day of treatment with the low dose regimen, a mean of 21% (range 9-68%) of the injected dose was recovered from the urine; and on the third or fourth day a mean of 44% (range 17-76%) of the gentamicin injected on that day was recovered.In 4 infants who died tissue gentamicin levels were measured in the liver, lungs, heart, kidneys, and brain, the highest concentration being in the kidney with low levels in the heart, liver, and brain, while levels in the lungs were intermediate. Neonatal renal and pulmonary infections are thus likely to be suitably treated with gentamicin.Bacteriological studies confirmed the effectiveness of gentamicin in the treatment of neonatal infection, but a dosage regimen derived by extrapolation from older children frequently resulted in inadequate serum levels, and a higher dosage regimen giving more satisfactory results was therefore defined.     

Plasma lecithin: cholesterol acyltransferase and plasma lipolytic activity in preterm infants given total parenteral nutrition with 10% or 20% Intralipid

The effect of 10% or 20% Intralipid on lipid clearing enzymes, plasma lipids and apoproteins was investigated during the first 5 days after birth in 37 premature infants maintained on total parenteral nutrition; 21 infants received 20% and 16 received 10% Intralipid, respectively. Lipid was infused over a 20-h period at rates of 1, 2 and 3 g/kg/day on consecutive days. Plasma lecithin: cholesterol acyltransferase (LCAT) activity was low and increased significantly (p < 0.05) only during infusion of 3 g/kg/day in both groups of infants. Plasma lipolytic activity was generally not affected by the regimen orpreparation(10% or 20%) of Intralipid infused, except for higher (p < 0.05) levels at 3 g/kg/ day of 20% compared with prelipid infusion. Plasma triglyceride concentrations were similar after 10% or 20% Intralipid, whereas plasma total cholesterol was significantly higher during infusion of 2 and 3 g/ kg/day of 10% compared with 20% Intralipid. The efficient clearing of 20% Intralipid might be related to the lower lecithin: triglyceride ratio which is compatible with the low LCAT activity of premature infants. Apoprotein A-J, apoprotein B, cholesterol, LCAT, plasma lipolytic activity, triglycerides     

Changes in protein turnover after the introduction of parenteral nutrition in premature infants: comparison of breast milk and egg protein-based amino acid solutions.

Rates of protein turnover were measured in 20 infants receiving either Vamin Infant (group A) or Vamin 9 glucose (group B) as the amino acid source in total parenteral nutrition. A constant infusion of L-[1-13C]leucine was used to measure whole body leucine flux, and leucine oxidation rates were derived from measurements of total urinary nitrogen excretion. Infants were first studied when receiving only i.v. glucose and again on each of the next 4 d as total parenteral nutrition was gradually increased to a maximum of 430 mg nitrogen/kg/d and 90 nonprotein kcal/kg/d. Net protein gain and protein synthesis and breakdown rates increased progressively for all infants taken together over the study period as i.v. nutrition was increasing (p less than 0.001). There were no differences between groups in the changes in net protein gain and rates of protein synthesis and breakdown throughout the study period. Nitrogen retention on d 5 for the two groups was similar (60 +/- 16% and 67 +/- 11% in groups A and B, respectively). In a subgroup of infants, measurements were repeated on d 8, when the intake had been constant for 3 d. Protein retention was the same as on d 5, but both synthesis and breakdown were increased. It is concluded that rates of protein turnover increase significantly in response to increasing i.v. nutrition and that this elevation was not influenced by the composition of the amino acid mixture given.     

Enhanced lipid utilization in infants receiving oral L-carnitine during long-term parenteral nutrition

Fourteen infants requiring long-term total parenteral nutrition but able to tolerate small quantities of enteral feedings were randomized into carnitine treatment and placebo control groups. All infants had received nutritional support devoid of carnitine. Plasma carnitine levels and observed plasma lipid indices were not different before supplementation. Under standardized, steady-state conditions, 0.5 g/kg fat emulsion (intralipid) was administered intravenously over 2 hours both before and after infants received 7 days of continuous nasogastric or gastric tube L-carnitine (50 mumol/kg/day) or placebo. Plasma triglyceride, free fatty acid, acetoacetate, beta-hydroxybutyrate, and carnitine concentrations were observed at 0 (start of lipid infusion), 2, and 4 hours for pre- and post-treatment periods, and in addition at 6 and 8 hours after carnitine supplementation. Infants receiving carnitine had significantly greater beta-hydroxybutyrate plasma concentrations (P less than 0.05) and carnitine (P less than 0.001) at 0, 2, 4, 6, and 8 hours, and greater plasma acetoacetate concentrations (P less than 0.05) at 2, 4, 6, and 8 hours, compared with controls. Twenty-four-hour urinary carnitine excretion was very low for both groups before supplementation; after supplementation, excretion was higher (P less than 0.05) in the carnitine group. No significant differences were found between groups for plasma triglyceride or free fatty acid concentrations at any observation period. This study demonstrated enhanced fatty acid oxidation, as evidenced by increased ketogenesis, with L-carnitine supplementation in infants receiving long-term total parenteral nutrition.     

Total parenteral nutrition in infants. Blood levels of glucose, lactate, pyruvate, free fatty acids, glycerol, d-beta-hydroxybutyrate, triglycerides, free amino acids and insulin.

Two regimens (A and B) for TPN were designed to meet the requirements of newborn infants for calories, amino acids, fatty acids, electrolytes, trace elements and vitamins. Both "A" and "B" included fat emulsion (Intralipid). "A" contained fructose and glucose, "B" glucose only. "A" provided amino acids (Vamin) in proportions similar to those of whole egg, "B" similar to those of human milk. All nutrients were given simultaneously into peripheral veins by constant infusion. Nineteen patients (11 newborns, 8 infants) were studied for 1-28 days. Twelve infants recovered, 7 died. In none could TPN be regarded as the cause of death. Treatment was complicated by sepsis in 5 infants. During the course of treatment, blood levels of substrates and insulin were measured before, during and 30 min after discontinuation of TPN. Highly raised concentrations of circulating substrates seen in 3 infants seemed to be related to a poor clinical condition rather than to the regimen used. Infants in good condition tolerated TPN well. Low levels of branch-chained amino acids and tendency to ketonemia, when infusion was stopped, suggested that minimal rather than optimal supply of energy and of amino acids in relation to energy was provided with both regimens. Low insulin levels associated with elevated blood levels of substrates suggested that insulin administration to selected cases might be indicated. Fructose (0.30 g/kg X hour-1) given with regimen A increased blood lactate concentrations. Homocystinaemia appeared in 2 cases; disappearance after excess vitamin B6 administration indicated increased B6 requirement.     

ENHANCEMENT OF FAT ELIMINATION DURING INTRAVENOUS FEEDING

ABSTRACT. Forget, P. P. F. X., Fernandes, J. and Haverkamp Begemann, P. (Department of Paediatrics, Sophia Children's Hospital and Neonatal Unit, Erasmus University, Rotterdam, the Netherlands). Enhancement of fat utilization during prolonged intravenous feeding. AdaPaediatrScand, 63:750, 1974.-An 8-year-old girl with severe underweight caused by anorexia nervosa was treated with total intravenous nutrition for 4 weeks. During this period the Intralipid dose was stepwise increased, the doses of Vamin and glucose were kept constant. The Intralipid dose was monitored by the determination of the serum Intralipid levels. The fat utilization was investigated by intravenous fat tolerance tests and the estimation of postheparin lipoprotein lipase activity of the plasma. The Intralipid elimination constant increased from 796 to 2296/min, the postheparin lipoprotein lipase activity increased from 50 to 317 μEq fatty acid/min/l. These data enabled us to increase the Intralipid dose from 3 g fat/kg/per day to 8 g fat/kg/per day, without an increase of the triglyceride blood levels. We may conclude that lipoprotein lipase is an inducible enzyme. It is not clear which component of the hyper-caloric intravenous regime causes this induction.     

The role of parenteral lipids in supporting gluconeogenesis in very premature infants

We have previously demonstrated that very premature infants receiving glucose at 17 micromol/kg min plus appropriate supply of parenteral lipids (Intralipid) and amino acids (TrophAmine) maintained normoglycemia by glucose produced primarily via gluconeogenesis. The present study addressed the individual roles of parenteral lipids and amino acids in supporting gluconeogenesis. Fourteen premature infants (993 +/- 36 g 27 +/- 1 wk) (mean +/- SE) were studied for 8 h on d 5 +/- 1 of life. All infants were receiving standard TPN prior to the study. At start of study, the glucose infusion rate was decreased to approximately 17 micromol/kg min and either Intralipid (g + AA; n = 8) or TrophAmine (g + IL; n = 6) was discontinued. Data from 14 previously studied infants receiving glucose (approximately 17 micromol/kg min) + TrophAmine + Intralipid (g + AA + IL) are included for comparison. Gluconeogenesis was measured by [U-13 C]glucose, (g + AA) and (8 infants of the g + AA + IL group) or [2-13C]glycerol, (g + IL) and (6 infants of the g + AA + IL group). Infants studied by the same method were compared. Withdrawal of Intralipid resulted in decreased gluconeogenesis, 6.3 +/- 0.9 (g +AA) vs. 8.4 +/- 0.7 micromol/kg min (g + AA + IL) (p = 0.03). Withdrawal of TrophAmine affected neither total gluconeogenesis, 7.5 +/- 0.8 vs. 7.9 +/- 0.9 micromol/kg min nor gluconeogenesis from glycerol, 4.4 +/- 0.6 vs. 4.9 +/- 0.7 micromol/kg min (g+ IL and g + AA + IL groups, respectively). In conclusion, in parenterally fed very premature infants, lipids play a primary role in supporting gluconeogenesis.     

Effect of carnitine on lipid metabolism in the neonate. II. Carnitine addition to lipid infusion during prolonged total parenteral nutrition

The effect of carnitine administration on lipid metabolism and carnitine and acylcarnitine plasma values of newborn infants, given total parenteral nutrition for the first 7 days of life, was studied during a 4-hour infusion of Intralipid. An increase in plasma concentrations of total carnitine, free carnitine, and short-chain and long-chain acylcarnitine was found, but no significant change in triglycerides, free fatty acids, glycerol, or beta-hydroxybutyrate plasma values was noted, as compared with values obtained without carnitine administration. Moreover, the low free carnitine and short-chain and long-chain acylcarnitine plasma levels found in newborn infants after 7 days of total parenteral nutrition did not seem to impair the utilization of infused lipids. The results support the concept that the relation between the carnitine pool and lipid metabolism can be influenced by intravenous glucose infusion. Low carnitine plasma concentrations do not necessarily signify a depletion of body carnitine, and sufficient tissue carnitine concentrations can probably maintain good lipid utilization for an extended period.     

Total parenteral nutrition with intralipid in premature infants receiving TPN with heparin: effect on plasma lipolytic enzymes, lipids, and glucose

Plasma lipolytic activity (lipoprotein lipase and hepatic lipase), free fatty acids (FFA), triglycerides, cholesterol, and glucose levels were measured in 21 premature infants [gestational age 26-37 weeks (mean +/- SEM 30.4 +/- 0.63 weeks), aged 1-8 days (mean +/- SEM 3.00 +/- 0.35 days)]. All infants were maintained on total parenteral nutrition with heparin (1 U/ml) and were given Intralipid, 1, 2, and 3 g/kg/day, over 15 h on days 1, 2, and 3, respectively. Blood samples were drawn before and at the end of Intralipid administration. Baseline plasma lipolytic activity, before the start of lipid infusion, was 1.54 +/- 0.24 U/ml (1 U = 1 mumol [3H]oleic acid released from tri[3H]olein/h). Lipolytic activity increased after lipid infusion to 4.04 +/- 0.96, 4.32 +/- 0.63, and 6.09 +/- 1.00 U/ml on days 1, 2, and 3 of the study. Hepatic lipase amounted to 38-47% of total lipolytic activity. During the 3 days of lipid infusion, there were dose-dependent increases in plasma FFA, triglyceride, and cholesterol. Whereas FFA and triglyceride concentrations returned to prelipid infusion levels 9 h after stopping the infusion of Intralipid, 1, 2, or 3 g/kg, there was a cumulative increase in plasma cholesterol and glucose concentrations. The close correlation between FFA concentrations and plasma lipolytic activity (r = 0.655, p less than 0.001) suggests considerable intravascular lipolysis. The positive correlation between plasma FFA and triglycerides (r = 0.632, p less than 0.001) and FFA and cholesterol (r = 0.582, p less than 0.001) indicate, however, that intravascular lipolysis does not prevent the lipemia associated with Intralipid infusion to low birth weight infants.(ABSTRACT TRUNCATED AT 250 WORDS)     

Early versus Late Trophic Feeding in Very Low Birth Weight Preterm Infants

Objective

Improved survival of preterm infants, beneficial effects of trophic feeding and limited data on timing management of enteral feeding for very low birth weight preterm infants requires more researches to determine the exact starting time and increased volumes. This study aims to compare early (<48 h) versus late (>72h) trophic feeding with respect to important neonatal outcomes.

Methods

In a cohort study from September 2007 to October 2008, a total of 170 preterm infants (1000-1500 gram, 26-31 weeks) consisting of 125 who received trophic feeding enterally within the first 48 hours of birth (early group) and 45 fed enterally after 72 h0urs (late group), without major congenital birth defects and severe asphyxia entered the study. Bolus feeding was started in both groups at 1-2 cc/kg every 4-6 hours of human milk or preterm infant formula and was advanced 1-2 cc/kg/day if tolerated along with parenteral nutrition. Feeding intolerance, possibility of necrotizing entrocolitis (NEC), episodes of sepsis, body weight, length of NICU stay, and duration of parenteral nutrition were assessed serially.

Findings

There were no statistically significant differences in the clinical and maternal characteristics of infants in the two groups. The time to gain birth weight (13.75±5.21 vs 20.53±6.31 (P < 0.001)), duration of parenteral nutrition (9.26±4.572 days vs 14.11±6.415 days (P < 0.001)), hospital stay (12.14±8.612 vs 21.11±1.156 (P < 0.001)) were significantly shorter in early compared to late feeding group; none of the two groups experienced a high incidence of late onset sepsis (P = 0.73). There was 1 case of confirmed NEC in every group.

Conclusion

The benefits of early trophic feeding shown by this study strongly support its use for the preterm infants without adding to complications.     

Carnitine deficiency in premature infants receiving total parenteral nutrition: effect of L-carnitine supplementation

To investigate whether L-carnitine supplementation may correct nutritional carnitine deficiency and associated metabolic disturbances in premature infants receiving total parenteral nutrition, an intravenous fat tolerance test (1 gm/kg Intralipid over four hours) was performed in 29 premature infants 6 to 10 days of age (15 receiving carnitine supplement 10 mg/kg . day L-carnitine IV, and 14 receiving no supplement). Total carnitine plasma values were normal or slightly elevated in supplemented but decreased in nonsupplemented infants. In both groups, fat infusion resulted in an increase in plasma concentrations of triglycerides, free fatty acids, D-beta-hydroxybutyrate, and short-chain and long-chain acylcarnitine, but total carnitine values did not change. After fat infusion, the free fatty acids/D-beta-hydroxybutyrate ratios were lower and the increase of acylcarnitine greater in supplemented infants of 29 to 33 weeks' gestation than in nonsupplemented infants of the same gestational age. This study provides evidence that premature infants of less than 34 weeks' gestation requiring total parenteral nutrition develop nutritional carnitine deficiency with impaired fatty acid oxidation and ketogenesis. Carnitine supplementation improves this metabolic disturbance.     

早期不同剂量氨基酸在早产儿静脉营养中的应用价值研究

目的 探讨应用不同剂量氨基酸在早产儿静脉营养中的近期疗效及耐受情况.方法 根据早期应用氨基酸剂量的不同,将2013 年3 月至2014 年6 月收治的生后24 h 内入院,出生体重1 000~2 000 g 的86 例早产儿随机分成低剂量组(n=29,每日1.0 g/kg,每天增加1.0 g/kg,最大达每日3.5 g/kg),中剂量组(n=28,每日2.0 g/kg,每天增加1.0 g/kg,最大达每日3.7 g/kg),高剂量组(n=29,每日3.0 g/kg,每天增加0.5~1.0 g/kg,最大达每日4.0 g/kg),同时进行常规的其他静脉营养及肠内营养支持.结果 早产儿最大体重下降程度随氨基酸输注量增加而降低,恢复出生体重天数、肠道营养达100 kcal/(kg · d)天数、住院时间及住院费用均随氨基酸输注量增加而减少,头围增长则随氨基酸输注量增加而增加(均P<0.05).高剂量组早产儿血尿素氮(BUN)水平在生后7 d 时高于中剂量组和低剂量组(均P<0.05);肌酐、pH 值、碳酸氢盐、胆红素及转氨酶水平在生后7 d,以及并发症发生率在各组间差异均无统计学意义(均P>0.05).结论 早产儿在生后24 h内静脉应用高剂量氨基酸可以改善早产儿生后近期营养状况,但有一过性BUN 升高.     

Egg and breast milk based nitrogen sources compared.

A nitrogen source based on egg protein (Vamin 9 glucose) and an alternative with an amino acid profile more similar to breast milk (Vaminolact), were compared in 14 parenterally fed infants. Subjects were randomly allocated to receive one or other amino acid solution, but were otherwise given identical diets. At the start of the study the two groups did not differ significantly in postconceptual age, postnatal age, or weight. Over a six day study period on a stable intake of intravenous nutrients there was no significant difference in growth or nitrogen retention between the two groups. Plasma amino acid profiles in those receiving Vamin 9 glucose, however, were frequently abnormal. Notably, mean concentrations of potentially neurotoxic phenylalanine and tyrosine were significantly higher (140% and 420%, respectively) in patients fed Vamin 9 compared with those given Vaminolact. An amino acid solution based on the composition of breast milk protein therefore brings plasma amino acid profiles during parenteral nutrition closer to those found in breast fed infants, and reduces in particular, the risks of hyperphenylalaninaemia and hypertyrosinaemia.     

Lipid clearing in premature infants during continuous heparin infusion: role of circulating lipases

The nature of the lipases released into the circulation during low level continuous infusion of heparin (1 unit/ml total parenteral nutrition) and after bolus heparin injection (10 units/kg) was investigated in a group of 11 low birth weight infants (gestational age 27-34 wk, and postnatal age of 7-26 days) receiving total parenteral nutrition with Intralipid (0.5 g/kg). Hepatic lipase and extra-hepatic lipoprotein lipase were differentiated with the aid of an antibody specific for human hepatic lipase. The data show that continuous low level heparin infusion leads to a constant baseline postheparin lipolytic activity of 0.77 +/- 0.18 mumol free fatty acids released per milliliter serum per hour. Bolus heparin injection leads to peak lipolytic activity levels of 3.77 +/- 0.46 mumol free fatty acids per milliliter serum per hour, 10 min after injection. About two-thirds of the total postheparin lipolytic activity was of the hepatic type during low level continuous infusion or after bolus injection of heparin.     

Effect of parenteral fat emulsion on the pulmonary and reticuloendothelial systems in the newborn infant.

Analysis of phospholipids (PL), cholesterol esters, triglycerides (TG), and free fatty acids (FFA) was performed on plasma and RBCs in two sick low-birth-weight infants who received total parenteral nutrition including Intralipid for the first 9 and 12 weeks of life, respectively. There was an increase in the total concentration of the plasma IG and FFA in the infants receiving Intralipid as compared with controls. These elevated lipid levels were not detected by visual inspection of the plasma. When compared with control infants, higher levels of linoleic acid were found in the plasma and RBCs of infants receiving Intralipid while plasma PL contained less arachidonate. Histological examination of the lung in both infants who received Intralipid revealed numerous globules of sudanophilic material in alveolar macrophages and capillaries. There is a possibility that prolonged administration of Intralipid may be associated with altered pulmonary and reticuloendothelial system function.     

A modified vitamin regimen for vitamin B2, A, and E administration in very-low-birth-weight infants

INTRODUCTION: Very-low-birth-weight (VLBW; birth weight, <1,500 g) infants receive preterm infant formulas and parenteral multivitamin preparations that provide more riboflavin (vitamin B2) than does human milk and more than that recommended by the American Society of Clinical Nutrition. VLBW infants who are not breast-fed may have plasma riboflavin concentrations up to 50 times higher than those in cord blood. The authors examined a vitamin regimen designed to reduce daily riboflavin intake, with the hypothesis that this new regimen would result in lower plasma riboflavin concentrations while maintaining lipid-soluble vitamin levels. METHODS: Preterm infants with birth weight < or =1,000 g received either standard preterm infant nutrition providing 0.42 to 0.75 mg riboflavin/kg/day (standard group), or a modified regimen providing 0.19 to 0.35 mg/kg/day (modified group). The modified group parenteral vitamin infusion was premixed in Intralipid. Enteral feedings were selected to meet daily riboflavin administration guidelines. Plasma riboflavin, vitamin A, and vitamin E concentrations were measured weekly by high-performance liquid chromatography. Data were analyzed with the independent t test, chi, and analysis of variance. RESULTS: The 36 infants (17 standard group, 19 modified group) had birth weight and gestational age of 779 +/- 29 g and 25.5 +/- 0.3 weeks (mean +/- SEM) with no differences between groups. Modified group infants received 38% less riboflavin (0.281 +/- 0.009 mg/kg/day), 35% more vitamin A (318.3 +/- 11.4 microg/kg/day), and 14% more vitamin E (3.17 +/- 0.14 mg/kg/day) than standard group infants. Plasma riboflavin rose from baseline in both groups but was 37% lower in the modified group during the first postnatal month (133.3 +/- 9.9 ng/mL). Riboflavin intake and plasma riboflavin concentrations were directly correlated. Plasma vitamin A (0.222 +/- 0.022 microg/mL) and vitamin E (22.26 +/- 1.61 /mL) concentrations were greater in the modified group. CONCLUSIONS: The modified vitamin regimen resulted in reduced riboflavin intake and plasma riboflavin concentration, suggesting plasma riboflavin concentration is partially dose dependent during the first postnatal month in VLBW infants. Modified group plasma vitamin A and vitamin E concentrations were greater during the first month, possibly because the vitamins were premixed with parenteral lipid emulsion. Because of the complexity of this protocol, the authors suggest that a parenteral multivitamin product designed for VLBW infants which uses weight-based dosing should be developed.     

Postheparin plasma lipases and carnitine in infants during parenteral nutrition

Lipoprotein lipase is the rate-limiting factor for hydrolyzing triglycerides to glycerol and fatty acids. Carnitine is a cofactor in the transport of long-chain fatty acids through the mitochondrial membrane for oxidation. To assess these determinants of fat utilization during total parenteral nutrition, lipoprotein and hepatic lipase activities and carnitine concentrations of nine newborn infants, operated on because of gastrointestinal anomalies during the first day of life, were measured with specific methods. Total parenteral nutrition was built up in 3 days whereafter the infants received 3 g/kg of fat at a constant rate of infusion for 24 h/day. Lipoprotein lipase activity of post-heparin plasma increased from 14 to 35 mumol free fatty acids/ml/h during parenteral nutrition whereas hepatic lipase activity remained unchanged at 40 mumol free fatty acids/ml/h. Serum free carnitine and acylcarnitine levels decreased significantly during parenteral nutrition; urinary excretion of carnitine decreased also. In addition, serum cholesterol and phospholipids increased markedly during parenteral nutrition whereas serum triglycerides, free fatty acids, and blood beta-hydroxybutyrate remained unchanged. Serum apolipoprotein A-I concentrations were unaltered, apolipoprotein A-II underwent a transient increase, and apolipoprotein B increased monotonically during parenteral nutrition. The results suggest that under the present circumstances neither lipoprotein lipase activity nor carnitine resources are rate-limiting for the utilization of fat in newborn infants during total parenteral nutrition.     

Sequential Trial of Effect of Phenobarbitone on Serum Bilirubin of Preterm Infants

(1) Phenobarbitone in a dose of 8 mg/kg per day was given in twice-daily intramuscular doses to preterm infants with a gestational age of 36 completed weeks or less. The phenobarbitone was started within the first 24 hours after birth. (2) The peak serum bilirubin levels of these infants and matched, randomly selected, control infants were compared sequentially. A significantly lower (P [unk]0·05) peak bilirubin level was found in the treated group. (3) This lower level of serum bilirubin may be less liable to produce neurological damage in preterm infants.