Imipenem/Cilastatin Sodium as Reabsorbable Embolic Agent in Acute Lower Gastrointestinal Bleeding: A Multicentric Prospective Study

Background/Objectives: This study aims to analyze safety and effectiveness of imipenem/cilastatin sodium (IPM/CS) as an off-label embolic agent in acute lower gastrointestinal bleeding (LGIB). Methods: This is a multicentric prospective study including patients treated in emergency with endovascular embolization for acute LGIB. IPM/CS particles were prepared using one vial containing 500 mg/500 mg of IPM/CS in powder diluted with 5 mL of pure iodine contrast agent. Inclusion criteria were: acute bleeding managed with IMP/CS embolization, unfeasible/ineffective endoscopic management, availability of a pre-procedural contrast-enhanced Computed Tomography (CT) scan, pre- and post-procedural blood count, pre- and post-procedural hemodynamic balance evaluation, and follow-up to 30 days. Exclusion criteria were: patients treated in elective conditions, LGIB embolization performed without IMP/CS, IMP/CS adoption after other embolics, incomplete clinical–laboratoristic follow-up, and age < 18 years. Technical success was intended as angiographic disappearance of extravasation or significant reduction/stasis of blood flow to the target; clinical success was considered as hemoglobin values increase and/or stop transfusions and/or hemodynamic restoration. Result: Twenty-one patients were enrolled; bleeding etiologies included angiodysplasia, diverticular disease, gastrointestinal tumor-related bleeding, and post-surgical hemorrhage. Technical success rate was 100%, and clinical success rate at 30 days was 85.7%. Rebleeding occurred in three patients: two managed with surgery and one with coil re-embolization. Neither major and IPM/CS related complications occurred. Conclusions: In this study IPM/CS was a safe and feasible embolic agent in selected patients with acute LGIB; no bowel ischemia occurred during the 30 day follow-up. Future studies with larger samples are required to confirm these findings to include IPM/CS as an off-label alternative embolic agent in LGIB.