FWIW: If you are hospitalized for "scar tissue in the abdomen" related to a previous surgery, you have at the very least some type of bowel obstruction which is not an insignifficant problem.. and could lead to something much worse like a bowel perforation or infarction. This can be from adhesions, incisional hernias, internal hernias, or a combination thereof. Most commonly it affects the small bowel. Surgery for adhesions leads to more adhesions, especially if it requires an open approach. Most small bowel obstructions related to adhesions will resolve on their own with bowel decompression (nasogastric tube), IV fluids, and time. Surgical intervention is reserved for complete obstructions that will not resolve with conservative management, hernias, closed loop obstructions, perforation, or suspected bowel infarction.
From what I've read, Hayden required a combined laparotomy and sternotomy (completely open from top of the sternum to below his umbilicus) to repair a freak injury to his vena cava. It is truly amazing that he actually survived long enough to reach the hospital, let alone a surgical repair. That is possibly the worst vessel to injure. It carries the same amount of blood as the aorta, but handles like wet paper when trying to control it. A vena cava laceration typically exanguinates in a few minutes.