If arterial blood is returned after placing an IV catheter in the antecubital fossa, which artery is involved?

When blood is returned after placing an IV catheter in the antecubital fossa, it indicates that the catheter is positioned in a location where it has accessed a major vessel. The antecubital fossa is a space located at the front of the elbow, which is close to several anatomical structures, including major veins and arteries.

The brachial artery is the main artery supplying blood to the arm and runs through the antecubital fossa, making it the most likely candidate for involvement when arterial blood is returned from an IV catheter placed in that area. The brachial artery branches into the radial and ulnar arteries below the elbow, primarily supplying the forearm and hand. Hence, if the catheter inadvertently punctures the brachial artery, it would lead to the return of arterial blood.

Understanding the anatomical relationships within the antecubital fossa is crucial for recognizing the implications of arterial involvement during IV catheter placement. When blood is returned, healthcare providers should take precautions, as the presence of arterial blood can indicate a need to reposition the catheter to avoid complications such as hematoma or arterial injury.