Reasons to leave surgery clips in thoracic inlet during/after graft procedure?

My mother has severe hand pain ever since her graft was placed in her upper left arm. It was easy to gather that the surgery didn't go as well as planned, but could never get a straight answer. We were led to believe her discomfort was due to 'Steeling' syndrome, meaning the graft was working to well, taking more blood than it should, and starving the hand. Her graft has clotted 5 times. The IR surgeon put in a temp catheter as well after the 4th clotting. It clotted for the 5th time (and she's on Plavix and aspirin) last Thursday so they used the temp catheter successfully. The temp catheter clotted Saturday and Activaze didn't work. I just switched her to Original Medicare so we went to normal hospital. They ran labs and used activaze which worked the last 2 days. I've recently been told of a Subclavian artery blockage, keeping some blood from her dailysis arm, that they wanted to go in and fix. With the switch going on i request med files recently and found an x-ray showing surgical clips in the left thoracic inlet right about where the Subclavian Artery goes through the thoracic inlet. The only procedure done in this area is the Graft. I would like to know if anyone can think of a reason to purposely lleave surgery clips in this spot for a graft procedure (see attached).

Thanks folks.