However, a recent study of Moriwaki and al [1] found ultrasound was 85% sensitive and 100% specific for detection of free air in a prospective study of 484 patients. Some small studies have also investigated the utility of ultrasound contrast agents to detect active bleeding [2]. Ultrasound is relatively sensitive for free abdominal fluid. In a study, continuous scanning of Morison’s pouch during infusion of DPL fluid revealed a mean detection limit of 619 mL. Only 10% of ultrasonographers (attending physicians and residents in emergency medicine, radiology, and surgery) detected volumes less than 400 mL
