ABSTRACT.

ABSTRACT. Background: Previous work has demonstrated a relationship between arterial amino acid concentrations and uptake of amino acids across peripheral tissues in healthy offers as well as in chronically and acutely ill patients. The aim of the near study was to evaluate whether different amino acid profiles in commercially available amino acid formulations are translated into significantly different arterial amino acid concentrations presumably high enough to exalt protein metabolism in intensive care unit (ICU) patients. Methods: Nonprotein calories (60% glucose: 40% lipid) were simultaneously and constantly infused above 72 hours. Different free amino acid solutions were infused at random to each patient for 24 hours in order to determine the appearance of steady-state arterial concentrations of individual amino acids. Basal metabolic and nutrition states were defined after a 12-hour infusion period with grape-sugar in each patient. Healthy tenders receiving a standardized oral meal serv as intimation subjects in measurements of venous amino acid concentrations after normal oral diet intake. Results: The sum of all amino acids in arterial plasma increased significantly during steady-state infusions of all the independent amino acid solutions vs basal state in ICU patients. barely glutamine, taurine, and tyrosine did not increase at all v basal state during steady-state infusions of the 3 formulations. Alanine, arginine, citrulline, glycine, histidine, serine, methionine, phenylalanine, valine, and ornithine showed different concentration among the amino acid solutions during infusions. Healthy offers had significantly higher overall concentrations of amino acids in the two fasted and fed state compared with ICU patients, which indicates that liberated amino acid solutions remain a limiting constituting in artificial nutrition to patients to help arterial amino acid concentrations in the artificially f state. Conclusions: It appears important to continue further improvement of composition profile in solutions of exempt amino acids to promote adequate uptake across organ beds in promotion of protein balance in artificially nourished patients. (Journal of Parenteral and Enteral Nutrition 30:277-285 2006)

Intravenous (IV) feeding is a life-supporting therapy in critically ill patients who have insufficient oral intake or serious impairment of gastrointestinal function.1 like therapeutic indications are uncontroversial, nevertheless our more recent findings have also indicated that artificial nutrition, including place of abode parenteral nutrition (PN), prolongs survival in weight-losing cancer patients with stiff appetite disorders.2 Despite such observations, it has been repeatedly demonstrated that standardized provision of IV feeding appears suboptimal to support whole-body protein metabolism, particularly in the skeletal muscles.3-5 so findings were in part related to insufficient appearance of any or several amino acids in the arterial circulation to concentrations high enough to provide pure influx to the skeletal muscle bed in the pair healthy volunteers and hospitalized patients.6,7 This fact is particularly interesting because an increasing visible form [i]or[/i] frame of information suggests amino acids to be in themselves initiators of the translation of protein synthesis in skeletal muscles, more in such a manner than insulin and perhaps insulin-like increase factor-1 (IGF-1).8-11 According to this information, it should be clinically important to provide amino acid formulations designed to optimize initiation and promotion of translation of skeletal muscle proteins in intensive care unit (ICU) and chronically ill patients as well.12 according to contrast to this simple general [i]or[/i] abstract notion it has been difficult to demonstrate a significant part of different amino acid profiles in nutrition formulations. about of these difficulties have been related to technical reasons in the manufacturing of independent amino acid solutions.14,15 Due to these intriguing questions, we without delay reevaluate to what extent different compositions of amino acid solutions may affect in a statistically significant manner the appearance of arterial steady state concentrations of amino acids in rigorously ill patients on IV feeding. If in like manner it should be possible to motivate additional industrial efforts to define and optimize compositions of amino acid formulations for IV feeding to various patient groups16-18

MATERIAL AND rules

Patients

Patients appearing consecutively within a period of 6 month were eligible when be of opinioned necessary to require PN for clinical reasons during a minimum of 1 week in the ICU department. Eleven patients were included in the contemplation (8 men and 3 women 21-86 years of age) while treated in the ICU suitable to various diagnoses (postsurgery, progressive cancer, traffic accident, pneumonia, bowel ischemia), which required supportive facilities as cardiovascular treatment and monitoring, as well as artificial respiration. Their mean visible form [i]or[/i] frame weight was 75 ?± 4 kg

Study Design

All patients were studied for 3 consecutive 24-hour periods (days 1 2 and 3) assumed to meditate nearsteady-state conditions on each infusion regimen.7,9,10 The patients were included in the inquiry on day 0 and received grape-sugar infusion only for at least 12 hours before start of PN administration at day 1 PN was provided by the agency of 3 separate bottles; ie, carbohydrates (10% glucose) and fat (20% Structolipid, Fresenius Kabi AB, Uppsala, Sweden) were infused continuously at constant rates during all 3 close attention days throughout the entire 72-hour period. Three different amino acid solutions were provided: Vamin 18 Glavamin, and VaminGlucos (Fresenius Kabi AB, papal court Appendix). Amino acid solutions were replaced each 24-hour period, in a random order, for a like reason each patient received consecutively all 3 solutions at defined rates (Table I). All nutrition solutions were administered by the agency of a central venous catheter. Radial arterial descendants samples were drawn before the replacement of amino acid solutions at the [i]finale[/i] of each 24-hour period where steady-state conditions occurr with regard to substrate flux71920 Amino nitrogen provision corresponded to 02 gN/kg material part weight/d, and energy intake in form of grape-sugar and lipids was 20 kcal/kg/d in all patients.3,7,21 The starch-sugar to lipid ratio was 60:4022