What is the medical term or diagnosis name for hepatic venous gas in a critically ill patient?

Hepatic Portal Venous Gas (HPVG)

The medical term is hepatic portal venous gas (HPVG) or portal venous gas, which describes the radiographic finding of gas within the portal venous system of the liver 1, 2.

Clinical Significance and Context

HPVG is not a diagnosis itself but rather a radiographic sign that requires urgent evaluation to determine the underlying cause, which ranges from life-threatening bowel ischemia to benign conditions 2, 3.

Life-Threatening Associations

The most critical association is with bowel infarction and mesenteric ischemia, where HPVG indicates that intraluminal gas or gas produced by intestinal bacteria has entered the portal circulation 1, 2, 4:

• Bowel ischemia/infarction is the most common serious cause, particularly in the setting of acute mesenteric ischemia where HPVG strongly suggests bowel necrosis 1, 2, 3
• Necrotizing enterocolitis is another severe presentation 5, 2
• Severe acute pancreatitis with concurrent bowel ischemia can present with HPVG and carries grave prognosis 6

Non-Life-Threatening Causes

With increased use of CT imaging, HPVG is increasingly recognized in benign conditions 2, 3:

• Inflammatory bowel disease (ulcerative colitis, Crohn's disease) can cause HPVG without bowel necrosis 5, 4
• Post-procedural following colonoscopy or air contrast barium enema 5, 4
• Intra-abdominal abscesses and severe enteritis 4, 3
• Cholangitis with appropriate antibiotic treatment can resolve without surgery 3

Diagnostic Approach

CT scan is the most sensitive modality for detecting HPVG and should be performed urgently to assess for bowel ischemia 1, 2, 3:

• CT demonstrates gas in portal venous branches and can identify associated findings of bowel ischemia (pneumatosis intestinalis, bowel wall thickening, abnormal enhancement, free air) 1
• Plain radiography and ultrasound can detect HPVG but are less sensitive than CT 2, 4
• Color Doppler ultrasound may show characteristic findings 2

Management Algorithm

HPVG itself is not an automatic surgical indication—management depends entirely on the underlying cause and clinical presentation 2, 3:

Immediate Surgical Exploration Required When:

• Clinical signs of peritonitis (guarding, rebound tenderness, rigidity) are present 1, 3
• CT findings suggest bowel ischemia or infarction (pneumatosis, abnormal bowel wall enhancement, free air) 1, 3
• Patient has hemodynamic instability, metabolic acidosis, or organ failure suggesting mesenteric ischemia 1, 7

Conservative Management Appropriate When:

• Patient is hemodynamically stable without peritoneal signs 3
• CT shows HPVG but no evidence of bowel ischemia 3
• Known underlying condition (inflammatory bowel disease, recent endoscopy) explains the finding 5, 4
• Treatment includes broad-spectrum antibiotics, bowel rest, and management of underlying disease 4, 3

Critical Pitfalls

Do not assume all HPVG requires immediate laparotomy—detailed clinical assessment and CT findings must guide decision-making 3:

• Unnecessary exploratory laparotomy should be avoided in nonischemic conditions that respond to medical management 3
• However, delay in surgical intervention when bowel ischemia is present leads to mortality rates exceeding 60% 8
• The presence of HPVG in critically ill patients on vasopressors should raise high suspicion for non-occlusive mesenteric ischemia (NOMI) 1, 7

Prognosis

Prognosis is determined by the underlying pathology, not by the presence of HPVG itself 2:

• HPVG associated with bowel infarction carries mortality rates of 75-90% 2
• HPVG from benign causes (post-procedural, inflammatory bowel disease) has excellent prognosis with conservative management 5, 4, 3