Clamping the descending aorta by emergency thoracotomy is a well-known effective procedure to stop bleeding from lesions under the diaphragm. We successfully treated a case of cardiopulmonary arrest resulting from a massive duodenal ulcer hemorrhage using an intraaortic balloon occlusion (IABO) catheter instead of the conventional technique. Our experience suggests that IABO catheters can be used to treat patients with hemorrhagic shock regardless of the presence of cardiopulmonary arrest. This can be a life-saving procedure, which prevents ischemic brain injury. This article describes the advantages of using IABO catheters and our experience with this case.