Parenteral nutrition requires careful monitoring. Because the typical patient is in a protein-wasting state, parenteral nutrition therapy causes marked changes in fluid and electrolyte status and in glucose, amino acid, mineral, and vitamin levels. If the patient displays an adverse reaction or signs of complications, the parenteral nutrition regimen can be changed, as needed. (See “Parenteral nutrition administration,” page 546.) Assessing a patient’s nutritional status includes a physical examination as well as reviewing body weight, body composition, somatic and visceral protein stores, and laboratory values. Assessing the patient’s condition to detect complications requires recognizing the signs and symptoms of such complications, understanding of laboratory test results, and keeping careful records.

Because the parenteral nutrition solution is high in glucose content, the infusion must start slowly to allow the patient’s pancreatic beta cells to adapt to it by increasing insulin output. Within the first 3 to 5 days of parenteral nutrition, the typical adult patient can tolerate 3 L of solution daily without adverse reactions. Lipid emulsions also require monitoring.