Morphological fatty changes and function of the liver, serum free fatty acids, and triglycerides during parenteral nutrition.

Morphological fatty changes and function of the liver and serum free fatty acids and triglycerides were investigated in 37 catabolic patients (22 men, 15 women) given different parenteral nutrition regimens. In the glucose group energy was supplied as carbohydrate alone, in the lipid group as carbohydrates and fats, and in addition both groups received amino acids. In the amino acid group amino acids were given in excess and less energy was supplied as carbohydrates. Each patient served as his own control. During parenteral nutrition liver steatosis rose from 5% to 35% (p less than 0.001) in the glucose group and from 7% to 23% (p less than 0.01) in the amino acid group, but no increase occurred in the lipid group. Liver fat accumulation was associated with the rises in serum aminotransferase activities and with the lack of or a poor rise in serum prothrombin and proconvertin. The conjugation function of the liver was not disturbed. No cholestatis was found. During lipid infusion serum free fatty acids increased to 4.41 mmol/l (p less than 0.01) and serum triglycerides to 3.06 mmol/l (p less than 0.01), but they decreased to normal range 12 h after lipid infusion was stopped. In the glucose and amino acid groups serum free fatty acid levels fell, as expected, below the normal range. Serum triglycerides rose 1.4-fold (p less than 0.05) in the amino acid group. On the basis of liver tests and histological examination steatosis in the liver caused only a minor disturbance in hepatocellular integrity. The very high levels of serum free fatty acids and triglycerides during lipid infusion may be harmful in certain pathological states.