Abstract
INTRODUCTION: Gastrointestinal (GI) bleeding is still a rare but serious complication after cardiac surgery, with a reported mortality rate of 30%-50%. Acute hemorrhagic rectal ulcer (AHRU) is an uncommon cause of massive lower GI bleeding, typically seen in bed-ridden or critically ill patients, but has not previously reported following cardiac surgery. PRESENTATION OF CASE: We report two cases of AHRU occurring in the intensive care unit after cardiac surgery. The first patient, a 64-year-old man on chronic hemodialysis for diabetic nephropathy, and the second, a 71-year-old man with similar comorbidities, both developed sudden, painless hematochezia and hemorrhagic shock within 1 week postoperatively. Endoscopy revealed ulcerative lesions 3-10 cm above the dentate line. Hemostasis was achieved with heat probe cautery and clipping; both patients required repeated endoscopic interventions but ultimately recovered and were discharged. DISCUSSION: The pathogenesis of AHRU may involve ischemic mucosal injury related to diabetes, hemodialysis, anticoagulation, and prolonged supine positioning. Early mobilization and careful management of anticoagulation may reduce risk. Given the high recurrence rate of AHRU, scheduled second-look endoscopy may be beneficial. CONCLUSIONS: This is the first report of AHRU following cardiac surgery. Prompt bedside endoscopic intervention, intensive management of hemorrhagic shock, and early postoperative rehabilitation are essential for favorable outcomes. Development of a preventive care bundle for high-risk postoperative patients is recommended.