Week 2: Reinforcing concepts

The second week of my immersion experience has been characterized by the reinforcement of the concepts introduced during the first week through shadowing similar procedures in the OR and reading clinical literature. 

The week began with an angiography and angioplasty to treat a stent plagued by stenosis. This endovascular procedure began with gaining access to the blood vessels via the femoral artery. Guide wires were introduced into the blood vessels and advanced to the stent. Subsequently, a catheter was advanced along the guide wire and used to release radio-opaque contrast agent. Using real-time X-ray imaging (fluoroscopy) and digital subtraction angiography (removes bones and other non-contrast agent signal), flow through the blood vessels was evaluated. Once flow was characterized, angioplasty was utilized to address the stenosis. This involves introducing a balloon catheter, and inflating the balloon. Following deflation, angiography was used to confirm successful treatment of the stenosis. After addressing the stenosis, the surgeons did not choose to deploy a stent to ensure the vessel did not become occluded again. However, in a similar procedure I observed later during the week, a balloon-expandable stent was deployed to ensure vessel patency. This patient presented with claudication (pain in lower leg due to inadequate blood flow) due to atherosclerotic plaques occluding blood vessels supplying muscles in the leg. Angiography, angioplasty, and stent deployment were utilized to treat the occlusion.

Thus far, my shadowing experience has been dominated by observing procedures in the OR with very little exposure to the patient experience pre- or post-surgical intervention. However, this week I joined a patient prior to their arrival in the OR. This person was scheduled to receive an above the knee amputation due to tissue death in her leg. Her suffering was obvious, and I very much hope that the removal of her necrotic tissue brings relief. I observed a similar procedure during the previous week (below the knee amputation), and again I was struck by the precision of the surgeons and minimal blood loss sustained during this procedure.

 

Although I had the opportunity to observe a variety procedures in the OR, the vascular surgery team was away for a conference, making the week rather slow. However, I had the chance to begin reading the clinical literature related to the possible research project outlined by Dr. Schneider. The focus of the project is tentatively on vessel mobility after repair with fenestrated vs. branched stents or flexible, self-expanding vs. rigid, balloon-expandable stents. Our hypothesis is that flexible, self-expanding stents permit greater vessel mobility which allows greater respiratory-induced vascular deformation that contributes to reduced abdominal branch vessel stent failure. Thus far, I've been reading articles broadly related to the topic to get a good background on the methods utilized in the field. For instance, researchers from Stanford evaluated the geometry and respiratory-induced deformation of these vessels via computed tomography angiography during inspiratory and expiratory breath holds. This group used this imaging and subsequent analysis to ask a similar question to our hypothesis which indicates it will be a useful resource as we continue to develop this potential study.