Traumatic pneumoperitoneum. Implications of computed tomography diagnosis

Area of Science:

• Trauma Surgery
• Diagnostic Imaging
• Abdominal Radiology

Background:

• Pneumoperitoneum on plain radiographs after blunt abdominal trauma typically indicates bowel perforation, often necessitating surgery.
• The diagnostic significance of pneumoperitoneum identified via computed tomography (CT) in blunt abdominal trauma remains less defined.

Purpose of the Study:

• To evaluate the significance of CT-detected pneumoperitoneum in blunt abdominal trauma patients.
• To determine the rate of surgically confirmed bowel injury in patients with free intraperitoneal gas on CT scans.

Main Methods:

• Retrospective review of trauma patients over seven years with abdominal CT showing free intraperitoneal gas.
• Exclusion of patients with penetrating injuries or pre-CT peritoneal lavage.
• Analysis of surgical findings, diagnostic peritoneal lavage, GI studies, and clinical follow-up.

Main Results:

• Only 22% (4 of 18) of patients with CT-detected pneumoperitoneum had surgically confirmed bowel injury.
• The majority (14 of 18) had no evidence of gastrointestinal perforation after further evaluation.
• Potential alternative causes for pneumoperitoneum included pneumothorax (7 patients) and mechanical ventilation (2 patients).

Conclusions:

• CT-detected pneumoperitoneum in blunt abdominal trauma is not pathognomonic of bowel perforation.
• Exploratory laparotomy is not always mandatory; close clinical observation and further diagnostic tests are crucial.
• Diagnostic peritoneal lavage or contrast studies can aid in ruling out intestinal injury when surgery is not performed.