MA Orellana-Barrios MDa, D Sotello MDa, R Medrano MDb
Correspondence to M Orellana-Barrios MD
Figure 1,2. CT scans showing extensive gas within the hepatic portal venous system.
Figure 3. CT abdomen showing extensive vessel calcification, bowel dilatation, wall edema, and pneumatosis intestinalis.
A 73-year-old-woman presented with acute onset, severe (10/10), generalized abdominal pain associated with nausea and “coffee ground” emesis. The pain had been constant since onset approximately two hours before presentation. Her past medical history included hypertension, hyperlipidemia, diabetes mellitus type 2, peripheral arterial disease with bilateral subclavian stent placement, ESRD on hemodialysis, mild dementia, and depression. Current medications were quetiapine, amlodipine, simvastatin, aspirin, and sevelamer.
Physical examination: blood pressure 128/54 mmHg, heart rate 82 beats per minute, respiratory rate 20 breaths per minute, and room air O2 saturation 90%. The patient was in moderate distress. Her abdomen was distended and rigid with decreased bowel sounds.
Initial laboratory values: hemoglobin 11.2 g/dL, hematocrit 34.8%, leukocytes 4.4K/µL, platelets 172K/µL, BUN 27 mg/dL, creatinine 1.7 mg/dL, CO2 28 meq/L, glucose 137 mg/dL, Na 134 mEq/L, K 3.2 mEq/L, Ca 9.0 mg/dL, total bilirubin 2.9 mg/dL, AST 102 IU/L, alkaline phosphatase 248 IU/L, amylase 20 IU/L, lactic Acid 1.2 mmol/L. ECG showed atrial fibrillation with a heart rate in the 80s.
A computed tomography (CT) scan of the abdomen showed a distended small bowel with pneumatosis intestinalis, highly suggestive of bowel ischemia leading to necrosis. Extensive air in the portal venous system was present, mainly in the left hepatic lobe (Figure 1). The patient developed refractory shock despite resuscitation with IV fluids and vasopressor therapy. Surgical consultation was sought, but the patient and family decided to focus on comfort care. She died 4.5 days after symptom onset.
Acute mesenteric ischemia (AMI) is an uncommon urgent medical condition, almost always occurring in patients with significant cardiovascular comorbidities. Without surgical treatment, the mortality of acute mesenteric ischemia ranges from 87.1% to 99.4%, depending on the exact etiology (arterial embolism, arterial thrombosis, venous thrombosis, or non-occlusive mesenteric ischemia).1
CT scans of the abdomen with angiography have become the “new gold standard” in the early diagnosis of gastrointestinal ischemic injuries and are now recommended as the first imaging approach in patients with AMI. CT scan imaging has the advantage of showing both vascular and nonvascular findings associated with AMI.2 Hepatic portal venous gas (HPVG) is the presence of gas within the portal vein and its intrahepatic branches. The mechanism by which this occurs is not definitely known, since several conditions are associated with its occurrence. Some are lethal, and some are benign. Necrotic bowel is the main etiology in >70% of HPVG in adults.3 Necrotizing enterocolitis is a common cause of HPVG in children; HPVG is associated with particularly severe presentations or with Clostridium perfringens infections.4-7
Our case illustrates the association of multiple preexisting cardiovascular risk factors, ESRD, undiagnosed atrial fibrillation, and acute mesenteric ischemia. The computed tomography scan images in Figures 1-3 show some diffuse vascular calcification and some nonvascular findings of AMI, including bowel wall thickening, bowel dilatation, pneumatosis intestinalis, and HPVG. It is important to differentiate HPVG from pneumobilia, also called aerobilia. The latter tends to occur more centrally in the liver than HPVG, as the flow of bile is toward the liver hilum. Air in the gallbladder should also suggest that air within the liver parenchyma has traveled via the biliary system. Although, the images may be quite similar, pneumobilia is not associated with mesenteric ischemia. 8
Classically thought of as an “ominous radiologic sign,”9,10 HPVG has been historically associated with 75 to >90% acute mortality in the setting of abdominal pain and acute mesenteric ischemia.3 However, some recent case reports have shown that HPVG can be also present in transient conditions with much lower acute mortality, such Crohn’s disease11, gastric dilatation12,13, viral gastroenteritis14, and uncomplicated endoscopic procedures.15,16 The recent decrease in overall mortality of HPVG is associated with higher detection in benign conditions.17 The radiologic characteristics of HPVG on ultrasound may aid in determining the outcome of patients with HPVG, as dot-like patterns are associated with benign outcomes and streak or fruit-pulp like patterns are associated with poor outcomes.18
- Schoots IG, Koffeman GI, Legemate DA, Levi M, van Gulik TM. Systematic review of survival after acute mesenteric ischaemia according to disease aetiology. Br J Surg 2004;91(1):17-27.
- Oliva IB, Davarpanah AH, Rybicki FJ, et al. ACR Appropriateness Criteria (R) imaging of mesenteric ischemia. Abdom Imaging 2013;38(4):714-719.
- Liebman PR, Patten MT, Manny J, Benfield JR, Hechtman HB. Hepatic--portal venous gas in adults: etiology, pathophysiology and clinical significance. Ann Surg 1978;187(3):281-287.
- Arnon RG, Fishbein JF. Portal venous gas in the pediatric age group. Review of the literature and report of twelve new cases. J Pediatr 1971;79(2):255-259.
- Kennedy J, Holt CL, Ricketts RR. The significance of portal vein gas in necrotizing enterocolitis. Am Surg 1987;53(4):231-234.
- Molik KA, West KW, Rescorla FJ, Scherer LR, Engum SA, Grosfeld JL. Portal venous air: The poor prognosis persists. Journal of Pediatric Surgery 2001;36(8):1143-1145.
- Dittmar E, Beyer P, Fischer D, et al. Necrotizing enterocolitis of the neonate with Clostridium perfringens: diagnosis, clinical course, and role of alpha toxin. Eur J Pediatr 2008;167(8):891-895.
- Sherman SC, Tran H. Pneumobilia: Benign or life-threatening. The Journal of Emergency Medicine 2006;30(2):147-153.
- Khalaf N, Mittal S. Hepatic portal venous gas: an ominous sign of mesenteric ischemia. Clin Gastroenterol Hepatol 2014;12(6):xxix-xxx.
- Abboud B, El Hachem J, Yazbeck T, Doumit C. Hepatic portal venous gas: physiopathology, etiology, prognosis and treatment. World J Gastroenterol 2009;15(29):3585-3590.
- Delamarre J, Capron JP, Dupas JL, Deschepper B, Jouet-Gondry C, Rudelli A. Spontaneous portal venous gas in a patient with Crohn's ileocolitis. Gastrointest Radiol1991;16(1):38-40.
- Bani-Hani KE, Heis HA. Iatrogenic gastric dilatation: a rare and transient cause of hepatic-portal venous gas. Yonsei Med J 2008;49(4):669-671.
- Allaparthi SB, Anand CP. Acute gastric dilatation: a transient cause of hepatic portal venous gas-case report and review of the literature. Case Rep Gastrointest Med 2013;2013:723160.
- Mirmanesh M, Nguyen QS, Markelov A. A case of hepatic portal venous gas due to viral gastroenteritis. Hepat Med 2013;5:63-65.
- Kuo SM, Chang WK, Yu CY, Hsieh CB. Silent hepatic portal venous gas following upper gastrointestinal endoscopy. Endoscopy 2009;41 Suppl 2:E121-122.
- Salyers WJ, Jr., Mansour A. Portal venous gas following colonoscopy and small bowel follow-through in a patient with Crohn's disease. Endoscopy 2007;39 Suppl 1:E130.
- Nelson AL, Millington TM, Sahani D, et al. Hepatic portal venous gas: the ABCs of management. Arch Surg 2009;144(6):575-581; discussion 581.
- Pan HB, Huang JS, Yang TL, Liang HL. Hepatic portal venous gas in ultrasonogram--benign or noxious. Ultrasound Med Biol 2007;33(8):1179-1183.
Reviewers: Tinsay Woreta MD
Published electronically: 4/15/2015
Conflict of Interest Disclosures: none