Arterial embolization in gastrointestinal bleeding

BACKGROUND. Gastrointestinal bleeding is a common surgical emergency resulting in significant morbidity and mortality. The first line intervention in most cases is therapeutic endoscopy. When endoscopy fails or is not feasible, the traditional second line treatment is surgery. Emergency surgery is associated with significant morbidity and mortality, and the less invasive transcatheter arterial embolization (TAE) has become routine practice. The thesis aimed at studying the safety, efficacy and feasibility of TAE in the treatment of gastrointestinal bleeding. PATIENTS AND METHODS. The thesis comprises four original studies reviewing TAE in the management of bleeding pancreatic pseudoaneurysms (Study I), bleeding gastric and duodenal ulcers (Study II), lower gastrointestinal bleeding (Study III), and spontaneous hepatic tumor hemorrhage (Study IV). Studies I, II and IV are retrospective studies. Study II is a retrospective case-control study comparing TAE and surgery. The study included all patients undergoing angiography and embolization attempt for gastrointestinal bleeding in the Helsinki University Hospital during 2004-2017. Studied outcomes included the 30-day rebleeding, complication and mortality rates, need for blood transfusions, the durations of intensive care unit and hospital admissions, the incidence of delayed rebleeding and complications, and the analysis of overall survival. RESULTS. In Study I, TAE was technically feasible in 100% of patients and controlled the bleeding initially in 85%. The 30-day complication and mortality rates were 31% and 3%, respectively. Occurring in 50% of patients after splenic artery embolization, the most common complication was splenic infarction. In Study II, TAE was feasible in 92% and surgery in 100% of patients. The 30-day complication rate was lower after TAE than surgery (38% vs. 67%, P = 0.018). The 30-day rebleeding rates (25% vs. 16%, P = 0.641) and mortality rates (13% vs. 26%, P = 0.347) did not differ between TAE and surgery. In Study III, TAE was feasible in 96% of patients and controlled the bleeding initially in 74%. The 30-day complication rate was 36%. The most common complication was bowel ischemia occurring in 19% of patients and requiring surgical management in six patients (11%). The 30-day mortality rate was 6%. In Study IV, TAE was feasible in 92% of patients and controlled the bleeding in 84%. The 30-day complication and mortality rates were 55% and 33%, respectively. In-hospital mortality was higher in cirrhotic than non-cirrhotic patients (55% vs. 7%, P <0.001), whereas patients with bleeding hepatic metastases, but no cirrhosis, had an in-hospital mortality of 0%. CONCLUSIONS. TAE is an effective method in controlling gastrointestinal bleeding. Ischemic complications remain a concern especially in lower gastrointestinal hemorrhage. Although only a small percentage of bleeding patients require TAE, it has established its role in the multidisciplinary management of gastrointestinal bleeding and should be the preferred method over surgery in most non-traumatic bleeding emergencies.