Final answer:
Removing the needle while the tourniquet is in place can cause injury to the blood vessel, leading to bleeding and leakage of blood components from the site.
Step-by-step explanation:
Removing the needle while the tourniquet is still in place during a blood draw or intravenous (IV) therapy can lead to an injury. If the blood vessel is still constricted by the tourniquet when the needle is removed, there is a higher chance that the blood vessel may be severed. This situation could cause bleeding and allow blood and blood components, such as erythrocytes (red blood cells) and white blood cells, to leak out of the puncture site. In severe cases, it can also lead to a hematoma, where blood collects under the skin, causing discomfort and potentially more serious complications.