What is TPN

Parenteral nutrition in childhood: what's new?

introduction

The new guidelines for parenteral nutrition (PE) in childhood have been expected for years. The last recommendations of the European Society for Pediatric Gastroenterology and Nutrition (ESPGHAN) were published in 2010. The currently published guidelines are a revision of the recommendations that were published in 2005 and were drawn up in coordination and cooperation with the most important specialist societies.1,2,3)

A challenge in performing PE arises from the wide range of physiology of infants, toddlers, children and adolescents, ranging from extremely immature babies to adolescents with a body weight of more than 100 kg. The physiological and pathophysiological differences in the fluid, nutrient, mineral and vitamin balance are so significant in the various age groups that it is not possible to establish uniform guidelines.

Taking into account the special pediatric aspects, we would like to summarize the most important changes and the resulting recommendations in the following article. The literature used is compiled in the corresponding bibliography in the appendix.

Indications

  • All premature infants <35 weeks of gestation, as well as term infants who can only gain food after a delay, should receive total parenteral nutrition (TPN) or partial parenteral nutrition.
  • If the energy and nutrient requirements of a preschool or school age patient cannot be covered by enteral nutrient intake, a needs-based PE should be started within 7 days, depending on the nutritional status and the illness.

Peripheral and central venous access

  • Peripheral venous accesses have a lower complication rate compared to central accesses. They should be used especially with infants.
  • Routine addition of heparin to prevent thrombosis or to extend the duration of use has no proven benefit and is not recommended.
  • Taurolidine protects against catheter-associated bacterial infections and should be used during long-term use of central catheters.
  • Central catheters for long-term PE should preferably be made of silicone or polyurethane, not have an antimicrobial coating and the tip should project radiologically 0.5-1.0 cm above the carina. This increases the likelihood that the catheter tip will end up in the vena cava and thus outside the pericardial sac.
  • Standard solutions that are manufactured by a hospital pharmacy or a commercial supplier and are adapted to the nutritional needs and the age of the target group offer potential advantages in terms of safety, ease of use and costs.4)

Fluid, nutrient and energy requirements

The fluid and energy requirements 5) is age-dependent and is influenced by various factors such as illness, activity and therapy. For this reason, corresponding guideline values ​​for children who have to be looked after in the intensive care unit have now been added. In the Tables 1 and 2 the recommendations for the fluid and energy requirements of all non-intensive care patients are shown. The new recommendations regarding energy requirements are lower than before. No additional energy (5-10% of the total amount of energy) should be taken into account for enteral absorption.

carbohydrates

  • In term infants and children up to 2 years of age, the glucose intake should usually not exceed approx. 12 mg / kg body weight / min in order to avoid net lipogenesis with fat deposition and steatosis of the liver.
  • In newborns with a very low birth weight (<1500g), parenteral glucose intake should be accompanied by a parenteral intake of amino acids of 2-3g / kg body weight / day from the first day of life in order to reduce the risk of a negative nitrogen balance and hyperglycaemia.
  • A glucose intake of 8.6-14 g / kg body weight / day is recommended for children aged 28 days and up to a body weight of 10 kg. Children with a body weight between 11 and 30 kg should receive 4.3-8.6 g / kg body weight glucose per day, those with a weight between 31 and 45 kg 4.3-5.8 g / kg body weight / day. For adolescents with a body weight of over 45 kg, 2.9-4.3 g glucose per kg body weight / day are recommended.6)
  • Hyperglycaemia should be prevented because of the increased morbidity and mortality. Repeatedly measured hyperglycaemia> 10 mmol / L in patients in the intensive care unit and in neonates should be treated with continuous insulin infusion (if the hyperglycaemia persists after reducing the glucose intake).
  • Repetitive and / or prolonged hypoglycaemia below 2.5mmol / L should be avoided.

amino acids

  • The need for essential amino acids (per kilogram of body weight) in infants and premature babies is higher than in older children or adults.
  • The composition of amino acid preparations for pediatric PE is still suboptimal. This is because the solubility and stability requirements of free amino acids cannot be met.
  • Some amino acids are classified as non-essential in older children and adults, but as conditionally essential in newborns. Therefore, pediatric amino acid solutions should be used in infants and young children.
  • The supply of amino acids in premature babies with a very low birth weight should begin on the first day of life.
  • The minimum amino acid intake in the newborn should be 1.5 g / kg body weight / day in order to compensate for unavoidable protein losses and to avoid a negative protein balance. The intake of more than 4g / kg / day should not be exceeded at this age.7)
  • The minimum amino acid intake in children between the ages of one month and 3 years should be 1.0 g / kg / day in order to avoid a negative nitrogen balance. More than 2.5g / kg / day is not recommended because of the unclear effects on growth.
  • For patients between the ages of 3 and 12, an intake of 1.0-2.0 g / kg body weight / day is recommended, for adolescents 1.0 g / kg body weight / day.

Lipids and lipid emulsions

  • Lipid emulsions should typically represent 25-40% of the non-protein energy in totally parenterally fed patients.
  • Parenteral fat intake should not exceed 3-4 g / kg body weight per day in infants and 2-3 g / kg body weight per day in older children.
  • In premature and term newborns and infants, lipid emulsions should be administered over 24 hours or as a cyclical infusion for the duration of the usual PE in light-protected bags and infusion sets.
  • Lipid emulsions based on pure soybean oil should not be used for premature and term newborns and infants, as the sepsis rate is increased for these products.
  • Triglyceride concentrations in plasma should be checked regularly.
  • 2nd and 3rd generation lipid emulsions (mixture of soybean oil and other oils such as short-chain fatty acids, olive oil, fish oil) should be used for all age groups.8)
  • In critically ill children (especially with sepsis), the triglyceride concentrations should be checked more frequently and the fat intake reduced, but not stopped.
  • Elevated triglyceride levels can not only be caused by fats, but also by excessively high glucose intake (lipogenesis).

Electrolytes

  • With regard to the recommendations for electrolyte supplementation, little has changed: slightly higher doses of calcium and phosphate are now recommended in order to improve bone mineralization.9,10)