Where are vascular access devices placed and why?

Where are vascular access devices placed and why?

• A. In peripheral veins to ease insertion
• B. In the central venous system to accommodate hyperosmolar PN solution
• C. In the subclavian for comfort
• D. In the femoral for accessibility

Answer: (B)

Central venous access is used for parenteral nutrition because these solutions are highly concentrated and osmolar, requiring rapid dilution in a large, high-flow vein. Peripheral veins cannot safely tolerate such osmolar loads, leading to irritation, phlebitis, thrombosis, or tissue injury if a hyperosmolar solution is infused there. Delivering PN into the central venous system allows adequate dilution, accommodates higher concentrations and lipid emulsions, and is suitable for long-term use. While various central sites (such as subclavian or internal jugular routes) may be chosen based on clinical factors, the essential point is that central placement enables safe administration of hyperosmolar PN solutions.

Central venous access is used for parenteral nutrition because these solutions are highly concentrated and osmolar, requiring rapid dilution in a large, high-flow vein. Peripheral veins cannot safely tolerate such osmolar loads, leading to irritation, phlebitis, thrombosis, or tissue injury if a hyperosmolar solution is infused there. Delivering PN into the central venous system allows adequate dilution, accommodates higher concentrations and lipid emulsions, and is suitable for long-term use. While various central sites (such as subclavian or internal jugular routes) may be chosen based on clinical factors, the essential point is that central placement enables safe administration of hyperosmolar PN solutions.