Generic name: isoleucine, leucine, lysine acetate, methionine, phenylalanine, threonine, tryptophan, valine, alanine, arginine, glycine, histidine, proline, serine and cysteine hydrochloride
Dosage form: injection
Medically reviewed by Drugs.com. Last updated on May 11, 2020.
The objective of nutritional management of patients with liver disease is the provision of sufficient amino acid and caloric support for protein synthesis without exacerbating hepatic encephalopathy.
The total daily dose of Aminosyn-HF 8% (amino acid injection 8%) depends on daily protein requirements and on the patient’s metabolic and clinical response. The determination of nitrogen balance and accurate daily body weights, corrected for fluid balance, are probably the best means of assessing individual protein requirements. Dosage should also be guided by the patient’s fluid intake limits and glucose and nitrogen tolerances, as well as by metabolic and clinical response.
The recommended dosage is 80 to 120 g of amino acids (12 to 18 g of nitrogen) as Aminosyn-HF 8% per day. Typically, 500 mL of Aminosyn-HF 8% appropriately mixed with 500 mL of 50% dextrose supplemented with electrolytes and vitamins is administered over an 8 to 12 hour period. This results in a total daily fluid intake of approximately 2 to 3 liters. Patients with fluid restrictions may only tolerate 1 to 2 liters. Although nitrogen requirements may be higher in severely hypercatabolic or depleted patients, provision of additional nitrogen may not be possible due to fluid intake limits, nitrogen, or glucose intolerance.
In many patients, provision of adequate calories in the form of hypertonic dextrose may require the administration of exogenous insulin to prevent hyperglycemia and glycosuria. To prevent rebound hypoglycemia, a solution containing 5% dextrose should be administered when hypertonic dextrose solutions are abruptly discontinued.
Fat emulsion co-administration should be considered when prolonged (more than 5 days) parenteral nutrition is required in order to prevent essential fatty acid deficiency (EFAD). Serum lipids should be monitored for evidence of EFAD in patients maintained on fat-free TPN. Caution should be exercised in administering fat emulsions to patients with severe liver damage. Fat emulsion may obscure the presence of precipitate formation.
The provision of sufficient intracellular electrolytes, principally potassium, magnesium, and phosphate, is required for optimum utilization of amino acids. Approximately 60 to 180 mEq of potassium, 10 to 30 mEq of magnesium, and 10 to 40 mMol of phosphorus per day appear necessary to achieve optimum metabolic response. In addition, sufficient quantities of the major extracellular electrolytes (sodium, calcium, and chloride) must be given. In patients with hyperchloremic or other metabolic acidoses, sodium and potassium may be added as the acetate salts to provide bicarbonate precursor. The electrolyte content of Aminosyn-HF 8% must be considered when calculating daily electrolyte intake. Serum electrolytes, including magnesium and phosphorus, should be monitored frequently.
Hypertonic mixtures of amino acid and dextrose may be safely administered by continuous infusion through a central venous catheter with the tip located in the superior vena cava. Initial infusion rates should be slow, and gradually increased to the recommended 60 to 125 mL/hour. If the administration rate should fall behind schedule, no attempt to "catch up" to planned intake should be made. In addition to meeting protein needs, the rate of administration, particularly during the first few days of therapy, is governed by the patient’s glucose tolerance. Daily intake of amino acids and dextrose should be increased gradually to the maximum required dose as indicated by frequent determinations of glucose levels in blood and urine.
For patients in whom the central venous route is not indicated and who can consume adequate calories enterally, Aminosyn-HF 8% may be administered by peripheral vein with or without parenteral carbohydrate calories. Such infusates can be prepared by dilutions of Aminosyn-HF 8% with Sterile Water for Injection, USP or 5% to 10% dextrose to prepare isotonic or slightly hypertonic solutions for peripheral infusion. It is essential that peripheral infusion be accompanied by adequate caloric supplementation.
Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration, whenever solution and container permit. COLOR VARIATION FROM PALE YELLOW TO YELLOW IS NORMAL AND DOES NOT ALTER EFFICACY.
Care must be taken to avoid incompatible admixtures. Consult with pharmacist.
WARNING: Do not use flexible container in series connections.