Retinol (vitamin A) and the neonate: special problems of the human premature infant

Article Abstract:

Premature infants are at risk for retinol (vitamin A) deficiency; supplementation may help manage respiratory problems in these babies. Infants born prematurely are automatically at a disadvantage in terms of retinol stores because this vitamin accumulates in the baby throughout pregnancy. If the pregnancy is shorter than full-term, there is less time for vitamin A to be stored in the fetal liver. Other factors interact with the amount of retinol stored; the level of retinol binding protein (RBP), which carries retinol through the bloodstream, is also important. The RBP level is in turn influenced by the infant's protein and zinc nutrition; protein is commonly deficient in newborn premature babies. Thus RBP levels tend to be abnormally low in premature infants. Whether the cause of retinol deficiency is inadequate retinol stores or reduced RBP to carry it, the infant needs supplementation. The technology for achieving intravenous (into a vein) retinol supplementation is still being developed. The intravenous retinol preparation tends to adhere to the inside of the tubing used to infuse it, so a portion of the vitamin is lost and must be replaced. Retinol is vital to the health of premature infants with lung problems. This vitamin maintains and heals the epithelial (skin) cells that line the lungs. Many premature infants have initial respiratory difficulties and some treatments necessary to save their lives, such as oxygen delivery to the lungs, can also damage the lung tissue. Retinol supplementation may be useful for repairing injured lung tissue in this population, but more research is needed to discover how retinol functions in these infants.

Newborn infants, Vitamin A, Respiratory therapy, Respiratory therapy for newborn infants

---

Effects of high carnitine supplementation on substrate utilization in low-birth-weight infants receiving total parental nutrition

Article Abstract:

Carnitine is a fat-related molecule which is essential for cells to be able to utilize fats. Infants who have received total parenteral nutrition (TPN; feeding by intravenous means only) which was lacking in carnitine have developed carnitine deficiency and are possibly subject to difficulties in fat usage and thermogenesis (production of body heat), although this has been studied somewhat indirectly. The effect of supplementation with high doses of carnitine on fat utilization in 24 small premature infants was studied. Carnitine levels in 12 infants not given supplements were lower than those in preterm infants given human milk, while levels in supplemented infants were high, being closer to adult levels. Fat was not oxidized (used for energy by cells) well in unsupplemented infants but was significantly higher in infants given carnitine, and body fat stores were lower. The metabolic rate was higher in supplemented infants as well. However, these infants excreted more nitrogen, indicating breakdown of more protein, and this may have contributed to their slower attainment of birth weight (newborns usually lose weight after birth). The results suggest that high doses of carnitine are not advisable in low-birth-weight infants on TPN. (Consumer Summary produced by Reliance Medical Information, Inc.)

Physiological aspects, Parenteral feeding, Parenteral nutrition, Carnitine

---

Quantitative fecal carbohydrate excretion in premature infants

Article Abstract:

Although they are somewhat short of lactase and have insufficient pancreas function, premature infants are fed formulas containing half lactose (sugar found in milk) and half forms of glucose (a sugar). (Lactase is an enzyme needed to digest lactose; the pancreas secretes insulin into the blood to convert carbohydrates to energy and secretes enzymes into the intestines to digest proteins). Fecal carbohydrate excretion was measured in six healthy premature (32 weeks in womb) infants who were fed similar formulas except for the carbohydrate source. One formula used 100 percent lactose; the other used 50 percent lactose plus 50 percent forms of glucose. There were no significant differences in carbohydrate intake between the two formulas, stool output, or fecal carbohydrate excretion. Average fecal carbohydrate excretion was less than 0.2 grams per day, less than one percent of carbohydrate intake. Thus older (32 week) premature infants fed either 100 percent lactose or 50 percent lactose plus 50 percent glucose have minimal fecal losses of carbohydrates that have not yet been broken down by the digestion.

Analysis, Carbohydrates, Feces, Lactase, Beta galactosidase, Intestinal absorption, Lactose intolerance

Similar abstracts:

• Abstracts: Cassandra and the clinician: are clinical prediction rules changing the practice of medicine? A new mechanism for controlling the number of red cells in the blood
• Abstracts: Demonstration of specific binding of cocaine to human spermatozoa. Migrainelike headache and cocaine use
• Abstracts: Medical and nonmedical uses of anabolic-androgenic steroids. Physical activity counseling for healthy adults as a primary preventive intervention in the clinical setting: report for the US Preventive Services Task Force
• Abstracts: Radiation sensitivity of resting and activated nonspecific cytotoxic cells of T lineage and NK lineage. Rapid expression of protooncogenes c-fos and c-myc in B-chronic lymphocytic leukemia cells during differentiation induced by phorbol ester and calcium ionophore
• Abstracts: Gastrointestinal intraluminal pH in normal subjects and those with colorectal adenoma or carcinoma. Epidemiological study of asymptomatic inflammatory bowel disease: the identification of cases during a screening programme for colorectal cancer

This website is not affiliated with document authors or copyright owners. This page is provided for informational purposes only. Unintentional errors are possible.