Final answer:
During phlebotomy, the healthcare professional, not the restrainer, is responsible for occluding the blood vessel to make the veins more prominent for needle insertion. This is critical for successful blood collection and patient safety.
Step-by-step explanation:
The practice of occluding a blood vessel is commonly done during phlebotomy, which is the process of drawing blood. The healthcare professional drawing the blood will apply pressure to occlude, or block, the vessel to cause the veins to become more prominent, thereby facilitating the insertion of the needle.
This action is not the responsibility of the restrainer, if there is one, but of the one performing the phlebotomy. It is essential for the success of blood collection and the safety of the patient.
Occlusion during phlebotomy must be done carefully to avoid complications such as exercise-induced reduction in blood flow or stress-related vessel spasm.