Hepatic--portal venous gas in adults: etiology, pathophysiology and clinical significance.

The roentgenographic finding hepatic--portal venous gas (HPVG) has been reported extensively in the pediatric and radiology literature. The surgical implications and clinical significance have yet to be fully defined. This study reviews the 60 reported cases in the literature and adds four new cases. HPVG appears as a branching radiolucency extending to within 2 cm of the liver capsule. HPVG is associated with necrotic bowel (72%), ulcerative colitis (8%), intra abdominal abscess (6%), small bowel obstruction (3%), and gastric ulcer (3%). Mucosal damage, bowel distention and sepsis predispose to HPVG. The current mortality rate of 75% represents an improvement from previous experience. Analysis of survivors indicates that the finding of HPVG requires urgent surgical exploration except when it is observed in patients with stable ulcerative colitis.