One of the larger veins of the upper limb is the median antebrachial vein. It runs along the forearm, which extends between the elbow and the wrist. Many veins correlate with synonymous arteries (with parallel branching and distribution patterns). However, this independent vein is one of the exceptions to the rule. The median antebrachial vein drains the palm and anterior forearm into the basilica vein or median cubital vein. It stems off into smaller superficial branches in the palm and anterior forearm. These are known as tributaries. Given its size, the median antebrachial vein is an easy place to insert an intravenous fluid drip (IV). However, IV insertion in this region restricts a patient's mobility. IVs are used to help administer solutions into the body through the veins. Lying near the skin's surface, veins have thin walls, lower blood pressure than the arteries, and the ability to expand. This makes veins well-suited for IV needle insertion and carrying the injected fluid. IV administration enlists larger veins for long-term therapy or for treatments that use high volumes of fluid, such as total parenteral nutrition (TPN) when nutrition is received on an exclusively intravenous basis. TPN is used when a patient cannot digest their food in the normal way. This may occur if a person has a gastrointestinal disorder. TPN may also be used for people who have lost the ability to swallow.