Reoperative versus conservative management for gastrointestinal fistulas. Development of a fistula is a serious complication. It is necessary to identify its anatomic and pathologic features, as these can influence the outcome of treatment independent of the primary disease. Electrolyte abnormalities should be addressed as volume deficits are being restored. Sepsis, the most common cause of death in patients with fistulas, must be controlled, and the skin must be protected. Reoperation and conservative management are not opposing forms of therapy but rather are complementary. 