Investigation of the acute abdomen

The ‘acute abdomen’ accounts for the majority of general surgical emergency admissions. The causes range from life-threatening surgical emergencies to benign, gynaecological and even medical conditions. A systematic approach is required for accurate diagnosis. For most patients with an acute abdomen, investigations will supplement a careful structured history and examination. Appropriate investigations are important, to confirm the diagnosis and start treatment. However, over investigation can delay treatment and worsen outcome. It is essential to differentiate between those patients who require immediate surgery and resuscitation in theatre (e.g. abdominal aneurysm rupture) and those in whom further investigation will aid in their diagnosis and management. The goals of any investigation should be to (1) establish a diagnosis from a list of differentials; (2) provide information on the patient’s fitness for surgery; and (3) determine if or what type of surgical procedure is required (e.g. open or endovascular repair of a ruptured aneurysm). This contribution will discuss the differential diagnosis of an acute abdomen and the investigations that aid in the establishment of a diagnosis.