Acute Abdomen for Intensive Care Medicine Purposes The acute abdomen in intensive care unit patients still remains a diagnostic and therapeutic challenge. Without any delay it has to be decided when to start with surgical interventions. Bedside diagnostic procedures such as sonography, analysis of fluid drainage, endoscopy and X-ray studies can identify the underlying problem in more than 60% of all cases. The therapeutic spectrum in patients with acute abdomen following surgical procedures has changed by the development of new interventional techniques. Intra-abdominal abscesses can be effectively managed by percutaneous drainage in more than 80% of cases. In diffuse peritonitis the surgical strategy based on primarily resolving the source of infections is generally accepted as the most important feature. In most cases surgical options are restricted to control of infectious focus, débridement and purging the abdominal cavity (standard procedure). Today, additive surgical measures are not required on a routine base. The advantage to the patient is obvious. Due to reduction of the number of reoperations, stabilization of organic functions, e. g., with early spontaneous breathing, mobilization, and enteral feeding, can be achieved in a faster way. In these patients intensive care medicine is easier, less invasive and more safe.