Certification of Pharmacy Technicians (ExCPT) Practice Exam

A heparin lock is used with a/an?

1. Short piece of tubing

2. LVP solution

3. TPN solution

4. Peristalic pump

The correct answer is: TPN solution

A heparin lock, often referred to as a locking system, is primarily used with a short piece of tubing. It is designed to prevent clotting in intravenous lines while allowing for intermittent access to the vascular system. This is especially useful when a patient requires regular infusions or blood draws but does not need continuous IV therapy. For instance, if a heparin lock is placed, it can be flushed with heparin to maintain patency, ensuring the line remains open for future access without needing continuous infusion. While LVP (large volume parenteral) solutions and TPN (total parenteral nutrition) solutions may be administered through IV lines, a heparin lock itself does not directly relate to these types of solutions. Instead, it is typically used with short lengths of tubing to facilitate quick access to the venous system. A peristaltic pump is a device used to dispense fluids and is not inherently related to the function of a heparin lock. In summary, the primary purpose of a heparin lock aligns with the need for quick and safe venous access, fitting best with the use of a short piece of tubing rather than the other options listed.