Is there any part of an AV fistula that exits the skin?

The correct choice indicates that there is no part of an arteriovenous (AV) fistula that exits the skin. An AV fistula is a surgically created connection between an artery and a vein, typically performed for patients requiring chronic hemodialysis. The intention of this procedure is to facilitate easier access to the bloodstream for dialysis by providing a larger, more durable vessel for blood drawing and return.

In this case, the entire structure of the AV fistula is internal, designed to remain beneath the skin's surface once the surgical site has healed. This connectivity allows blood to flow from the artery into the vein, increasing the vein's size and strength over time, which is vital for the effectiveness of periodic dialysis.

In terms of contrasting the other options, some may suggest that the procedure could involve external components, but that is not the case with a typical AV fistula—those characteristics may apply to catheters or grafts designed for short-term use. So, for a properly created AV fistula, the answer must emphasize that nothing exits the skin, underscoring the internal nature of this important medical intervention.