**Question:** Complication of total parenteral nutrition is:-

A. Hyperglycemia
B. Hypertriglyceridemia
C. Hypercholesterolemia
D. Hypokalemia

**Core Concept:** Total parenteral nutrition (TPN) is a form of artificial nutrition that provides essential nutrients (glucose, amino acids, fatty acids, vitamins, and minerals) via a central vein to patients who are unable to absorb nutrients orally or through the gastrointestinal tract.

**Why the Correct Answer is Right:** The correct answer, D. Hypokalemia, occurs due to the infusion of glucose-free saline containing potassium chloride. In TPN, glucose is replaced by dextrose, which is a form of glucose. The infusion of a high volume of glucose-free saline may lead to a decrease in blood potassium levels (hypokalemia).

**Why Each Wrong Option is Incorrect:**

A. Hyperglycemia (Option A) is less likely as TPN is typically glucose-rich, causing increased blood glucose levels. However, this may occur in some cases where dextrose levels are excessively high or if the patient has insulin resistance.

B. Hypertriglyceridemia (Option B) may occur due to excess lipid infusion in patients with impaired lipoprotein lipase activity. However, this is less likely than hypokalemia.

C. Hypercholesterolemia (Option C) may occur due to lipid infusion, but this complication is less common compared to hypokalemia and hypertriglyceridemia.

**Clinical Pearl:** Careful monitoring and adjustment of TPN composition are crucial to prevent these complications. TPN is usually administered under close medical supervision to ensure appropriate fluid, electrolyte, and nutrient balance.

**Correct Answer:** D. Hypokalemia (K+ ion) is a significant complication of TPN due to the infusion of potassium-free fluids.