Gastrointestinal (GI) complications following adult cardiac surgery are rare (0.3–3%) but carry high morbidity and mortality, contributing disproportionately to postoperative deaths (up to 38%). They arise mainly from splanchnic hypoperfusion, systemic inflammation, embolization, and low cardiac output, exacerbated by prolonged cardiopulmonary bypass (CPB), vasopressor dependence, and preoperative organ dysfunction. Common complications include GI bleeding (upper/lower), mesenteric ischemia, hepatic dysfunction, pancreatitis, ileus, colonic pseudo-obstruction, Clostridium difficile colitis, dysphagia, and acute cholecystitis. Mesenteric ischemia has the highest mortality due to delayed diagnosis. Key risk factors: advanced age, extended CPB, renal failure, mechanical ventilation, and high-dose inotropes. Symptoms are often subtle or obscured in sedated/critically ill patients, necessitating high clinical suspicion and rapid diagnostic evaluation. Management emphasizes prevention, early detection, and multidisciplinary intervention. Preventive measures include optimizing perfusion, minimizing CPB duration, hemodynamic stabilization, early enteral feeding, and avoiding ulcerogenic/hepatotoxic agents. Once diagnosed, care involves anesthesiologists, intensivists, surgeons, and gastroenterologists to restore perfusion, support organ function, and treat specific pathology. Vigilant perioperative monitoring and coordinated team-based care are critical to reducing GI complications and improving outcomes after cardiac surgery.