Though it is rare to puncture an artery in an attempt to cannulate a vein, it does happen. The brachial artery is located near the basilic vein, and is one that is of importance since it is in an area that may be selected for venipuncture. Because arteries are deeper than veins these events most likely happen when blindly digging for a vein or attempting to find deeper veins due to difficult venous access.
“The danger of a complication from an inadvertent arterial puncture is that a leak could go undetected and cause an accumulation of blood in an area that can cause a compression injury to a nearby nerve. This type of injury could permanently damage the nerve and lead to a lawsuit.”
When palpating the vein that is selected it is important to feel for a pulse as that is an indication that the selected area may be an artery. In addition, the use of vein illumination may assist in finding more suitable venipuncture sites that allow you to avoid veins in the vicinity of an artery.
Source: Allied Health Blog