Review Question - QID 102645

This patient with suddenly worsening abdominal pain and frequent over the counter pain medication (likely NSAID) usage has likely developed a perforated viscus as evidenced by the upright radiograph demonstrating pneumoperitoneum.

A perforated peptic ulcer is the most common cause of bowel perforation. Patients will often give a history of pain that comes and goes over the course of days to weeks, followed by a sudden worsening of pain. Exam typically reveals severe abdominal pain with peritoneal signs such as abdominal rigidity, guarding, and rebound tenderness. If there is high clinical suspicion, an abdominal or chest radiograph can be ordered to look for abdominal free air. If present, operative intervention is typically required to find the source of perforation and repair the affected bowel. Emergent exploratory laparotomy with surgical repair is indicated for all patients with bowel perforation.

Tanner et. al review pneumoperitoneum. They discuss the wide differential for this radiographic finding to include operative emergencies such as perforated viscus, as well as benign causes such as the presence of postoperative air.

Figure A shows a radiograph demonstrating free air under the diaphragm which is concerning for a perforated viscus. Note the lucent area between the liver and diaphragm, characteristic of this condition.

Incorrect Answers:
Answer 1: Acute pancreatitis would also present with abdominal pain. However, associated nausea and vomiting as well as a history of alcohol use or gallstone disease would be expected. Acute pancreatitis would not explain pneumoperitoneum visualized on an upright radiograph.

Answer 2: Gastritis typically presents with abdominal pain and associated vomiting. This patient who is likely frequently using NSAID medications probably had developed some degree of gastritis or peptic ulcer disease prior to this presentation. However, the sudden worsening of pain and pneumoperitoneum visualized on an upright radiograph suggests a perforated viscus.

Answer 4: Pneumothorax would present with pleuritic chest pain and hypoxia. Chest radiograph would demonstrate an absence of lung markings that extend to the periphery. The free air on this patient's radiograph is visualized below the diaphragm, not in the pleural space.

Answer 5: Ruptured abdominal aortic aneurysm would present with sudden abdominal or back pain, hypotension, and tachycardia and requires blood products and emergency vascular surgery. It would not present with pneumoperitoneum visualized on an upright radiograph.

Bullet Summary:
A perforated viscus presents with sudden and severe abdominal pain, peritoneal exam findings, and pneumoperitoneum visualized on an upright radiograph.