Accuracy and indications of diagnostic studies for extracranial carotid disease.

We reviewed extracranial carotid studies in two groups of patients. The first group consisted of 200 patients who had been evaluated by both duplex scanning (DS) and direct arch-selective carotid arteriography (SCA). The second group consisted of 100 patients who had been evaluated by both intravenous digital subtraction angiography (IDSA) and conventional SCA. In 200 patients DS disclosed a 92% accuracy in delineating stenotic internal carotid disease and was accurate in recognizing ulcerative disease in 76% of patients. A review of the 100 patients studied by both IDSA and SCA showed that in 40% IDSA gave excellent correlation with SCA; in 35%, good correlation; and in 25%, poor correlation. In 10% DS was more accurate in delineating ulcerative disease than was IDSA, and on occasion DS was even more diagnostic than SCA. The relative accuracy, cost, risk, and clinical usefulness of each carotid diagnostic modality are discussed.

Complications of renal dialysis access procedures.

The complications of 2,179 dialysis access procedures of various types have been reviewed in an effort to determine their possible prevention and management. Scribner arteriovenous shunts or central venous catheters were preferred for temporary dialysis. Infection was a common complication of central venous catheters, but responded well to removal of the catheter. Brescia-Cimino fistulae were preferred for long-term dialysis, but were often not possible because of inadequate veins or the need for relatively urgent hemodialysis. The most useful secondary shunt was the straight forearm synthetic polytetrafluoroethylene (PTFE) graft whose most common complication was thrombosis due to intimal hyperplasia at the venous anastomosis. In most cases, this complication could be corrected by patch grafting or by extension bypass. Infection was infrequent with PTFE shunts and, when localized, was sometimes successfully treated by drainage, antibiotic therapy, and topical povidone-iodine. The principal complications of long-term peritoneal dialysis were peritonitis and tunnel infection that responded to antibiotic therapy and/or removal of the catheter. Compulsive care in access insertion and meticulous management during dialysis has permitted very satisfactory long-term hemodialysis and peritoneal dialysis.

Aortoenteric fistula.

Because of the unacceptably high mortality rate associated with aortoenteric fistula, we have constantly re-evaluated our experience with this lesion. A study of 31 cases of aortoenteric fistula proven at operation has provided a better understanding of the prevention and management of aortoenteric fistula. Prevention remains the primary goal, as the treatment of this complication even with the adoption of recommendations made in our paper can be expected to continue to carry a significant late mortality rate. The most important point in prevention is to provide adequate protection between gut and graft, using tissue, prosthetic cuff and correct reperitonealization techniques. Systemic or groin infection should be followed by prompt total removal of the graft before the onset of aortoenteric fistula. Once aortoenteric fistula is present, early operation with removal of the graft, proper closure of the aortic and enteric openings, and sump drainage of the area is indicated. Blood supply to the extremities is supplied by extra-anatomic bypass or endarterectomy if the underlying problem is arterial occlusive disease. Paraprosthetic aortoenteric fistulas may be diagnosed early by the presence of fever, blood culture, and a high degree of suspicion. CAT and gallium 67 scanning can be helpful in identifying this early type of fistula.