Pneumoperitoneum is defined as the presence of free air in the abdominal cavity. The most common cause of pneumoperitoneum is intestinal perforation, which usually requires surgical intervention. Nonsurgical pneumoperitoneum (NPS) is defined as the presence of free air in the abdominal cavity without visceral perforation by an intrathoracic route, which commonly occurs in patients on mechanical ventilation in intensive care units. NSP, when properly diagnosed, can be successfully treated conservatively without surgery, and intensivists and surgeons should be aware of this entity associated with mechanical ventilation to avoid unnecessary surgical intervention.