Metabolic complications of parenteral nutrition in adults, part 1

Purpose. Common metabolic complications associated with parenteral nutrition (PN) are reviewed, and the consequences of overfeeding and variables for patient monitoring are discussed. Summary. Although PN is a lifesaving therapy in patients with gastrointestinal failure, its use may be associated with metabolic, infectious, and technical complications. The metabolic complications associated with PN in adult patients include hyperglycemia, hypoglycemia, hyperlipidemia, hypercapnia, refeeding syndrome, acid-base disturbances, liver complications, manganese toxicity, and metabolic bone disease. These complications may occur in the acute care or chronic care patient. The frequency and severity of these complications depend on patient- and PN-specific factors. Proper assessment of the patient's nutritional status; tailoring the macronutrient, micronutrient, fluid, and electrolyte requirements on the basis of the patient's underlying diseases, clinical status, and drug therapy; and monitoring the patient's tolerance of and response to nutritional support are essential in avoiding these complications. Early recognition of the signs and symptoms of complications and knowledge of the available pharmacologic and nonpharmacologic therapies are essential to proper management. PN should be used for the shortest period possible, and oral or enteral feeding should be initiated as soon as is clinically feasible. The gastrointestinal route remains the most physiologically appropriate and cost-effective way of providing nutritional support. Conclusion. PN can lead to serious complications, many of which are associated with overfeeding. Close management is necessary to recognize and manage these complications.