Which vein is most commonly used for IV insertion in adults?

The median cubital vein is the most commonly used site for IV insertion in adults due to several key factors. This vein is located in the antecubital fossa, which is the region of the arm near the elbow. Its prominent, superficial position makes it easily accessible, reducing the likelihood of complications during insertion.

Additionally, the median cubital vein generally has a larger diameter compared to other veins, allowing for the accommodation of larger gauge catheters, which are often needed for fluid resuscitation or blood transfusions. It typically has fewer nearby nerves and arteries, providing a safer placement option for the health professional performing the IV insertion.

The femoral vein, while larger, is less commonly used in routine settings due to its deeper location and higher risk for complications, such as bleeding and infection. The jugular vein is often reserved for specific situations, such as in this scenario, where central venous access is required. Lastly, the radial vein is not a primary site for IV therapy due to its smaller size and the proximity of the radial artery, which increases the potential for complications. Thus, the median cubital vein is the preferred choice for IV insertion in adults, balancing accessibility, safety, and effectiveness.