ACS is due to a rapid increase in intra-abdominal pressure. Although ACS may occur in both surgical and nonsurgical patients, patients who have abdominal or pelvic trauma and/or require massive fluid replacement are at increased risk. Critical care nurses are in a unique position to recognize early signs and symptoms of increased intra-abdominal pressure to ensure timely intervention. Aggressive hemodynamic, pulmonary, and operative management is essential for the optimal outcome of patients with ACS. Without definitive treatment, multisystem organ dysfunction and death ultimately ensue.