Retroperitoneal hematoma formation following elective open abdominal aortic aneurysm (AAA) repair may be occult. We report a case of recurrent hypotensive episodes in the postanesthesia care unit (PACU) that were temporarily treated successfully with fluid, blood products, and vasopressors. At reoperation, active bleeding was excluded; however, upon reopening the bovine pericardial patch closure of the retroperitoneum, hematoma between the aneurysmal sac and inferior vena cava (IVC) had caused IVC compression. Evacuation of the hematoma rapidly restored venous return and hemodynamics. This report describes a case of retroperitoneal hematoma formation and highlights challenges associated with diagnosing bleeding in this compartment.