Is a Perforated Peptic Ulcer the Most Common Cause of Free Intraperitoneal Gas?

Free gas under the diaphragm, also known as pneumoperitoneum, is most commonly associated with perforations in hollow viscera such as the stomach or intestines. The abdominal cavity is generally a closed space that does not contain air. When gas is detected within this area, it often indicates a rupture or perforation in an organ like the stomach or bowel, allowing air and other contents to escape into the peritoneal cavity. This condition can be clearly visualized using an upright or lateral decubitus abdominal X-ray, where the presence of gas beneath the diaphragm becomes evident.

A key clinical sign, the detection of free intra-abdominal gas should prompt immediate evaluation for gastrointestinal perforation. Patients with a history of peptic ulcer disease—particularly gastric ulcers—are at higher risk for developing such perforations. In these cases, the accumulation of gas may be more pronounced due to repeated or chronic damage to the stomach lining. This type of perforation often requires urgent surgical intervention to prevent life-threatening complications such as peritonitis or sepsis.

Severe abdominal pain is one of the primary symptoms associated with this condition, and individuals experiencing sudden, intense pain should seek medical attention immediately. Early diagnosis and treatment are crucial in minimizing complications and improving patient outcomes. Imaging studies, including computed tomography (CT) scans and plain abdominal X-rays, play a vital role in confirming the presence of free gas and identifying its source.