- Clinical science
Portal hypertension refers to a pathological elevation of portal venous pressure resulting from obstructions in portal blood flow, which may be either prehepatic (e.g., portal vein thrombosis), hepatic (e.g., liver cirrhosis), or posthepatic (e.g., right-sided heart failure). The subsequent backflow of blood may lead to portosystemic anastomoses, splenomegaly, and/or ascites. While portal hypertension may be diagnosed purely based on the presence of clinical signs and potential risk factors, medical imaging and laboratory tests are used to support the diagnosis in suspected cases. Management requires treating the underlying condition and reducing portal pressure with nonselective beta-blockers and portosystemic shunts.
A potentially life-threatening complication is acute hemorrhage of the esophageal varices caused by increased blood flow via portosystemic anastomoses. Patients present with sudden hematemesis and melena, as well as hypovolemic shock in some cases. In addition to stabilizing the patient, acute management of variceal bleeding includes reducing splanchnic blood flow with octreotide and endoscopic variceal band ligation. Prevention of (recurring) bleeding involves nonselective beta-blockers, endoscopic variceal ligation, or placement of transjugular intrahepatic portosystemic shunts (TIPS).
Portal hypertension is present if the portal venous pressure is ≥ 6 mm Hg (normal value: 1–5 mm Hg). Portal venous pressure > 10 mm Hg is clinically significant and > 12 mm Hg is associated with complications. Causes of portal hypertension can be classified as follows:
- Intrahepatic (most common)
Depending on the cause, portal hypertension may be either acute or chronic. Acute portal hypertension arises from acute portal vein thrombosis, while chronic portal hypertension may be due to chronic thrombosis, cirrhosis, or schistosomiasis.
- Signs and symptoms of the underlying disease (e.g., ),
- ↑ Blood flow via portosystemic anastomoses
- Congestive splenomegaly, followed by
- Upper gastrointestinal bleeding from portal hypertensive gastropathy, gastrointestinal ulcers, or diffuse lower gastrointestinal bleeding
- Transudative ascites
Clinical manifestations of portal hypertension (e.g., ascites) in a patient with a known risk factor (e.g., cirrhosis) may already suffice for diagnosis. In addition to investigating underlying conditions, diagnostic steps may include:
- Specific findings: : on duplex ultrasonography, visualization of a cavernous transformation of the portal vein indicates (chronic) portal vein thrombosis
- Unspecific finding: portal vein dilated to > 13 mm
- Indirect indications
- Abdominal CT: portal vein thrombosis is visible
- Esophagogastroduodenoscopy (EGD): assessment of and, if necessary, treatment of esophageal varices
- First line medication: nonselective beta-blocker (i.e., propanolol or nadolol)
Beta-blocker treatment in patients suffering from advanced liver cirrhosis (Child's class C) may lead to circulatory dysregulation. If negative effects outweigh the benefits, beta-blocker treatment should be reconsidered!
Transjugular intrahepatic portosystemic shunt (TIPS or TIPSS)
- A needle catheter inserted via the internal jugular vein → passed along to hepatic vein → pierced through liver parenchyma to intrahepatic branch of the portal vein → expandable metal stent is placed → side-to-side portocaval shunt
- Assures blood drainage from the portal to the systemic system, thus lowering portal pressure
- Total portosystemic shunts: The portal vein is completely shunted to the vena cava, thereby reducing portal pressure.
- Selective portosystemic shunts: The portal vein is partially shunted to the vena cava, thereby reducing portal pressure. This partial shunt prevents varices while continuing to allow portal perfusion
Esophageal variceal hemorrhage; refers to the bleeding of dilated sub-mucosal veins (varices) of the distal esophagus; and is a dangerous consequence of portal hypertension. It is the most common form of upper gastrointestinal (GI) bleeding in patients presenting with cirrhosis.
- Symptoms of upper GI bleeding (see ): signs of circulatory insufficiency, hematemesis, melena, and/or hematochezia
- Sudden onset of severe upper GI bleeding in a patient with signs of portal hypertension, typically in combination with liver failure
- If bleeding occurs following retching or vomiting, consider a Mallory-Weiss tear as a differential diagnosis.
Acute management of variceal hemorrhage
- Resuscitation and stabilization
- Octreotide for 3–5 days → inhibits secretion of vasodilative hormones, e.g., glucagon → indirect splanchnic vasoconstriction → reduces splanchnic blood flow
- Vitamin K is indicated for patients with coagulation disorders
- IV antibiotic prophylaxis (e.g., ciprofloxacin or trimethoprim-sulfamethoxazole): prevention of infections (SBP, urinary tract infection, pneumonia) and of septic complications due to bacteremia, as well as colon decontamination to reduce ammonia production of gut flora
- Erythromycin (a strong prokinetic agent) may be administered before gastroscopy.
Endoscopic band ligation (procedure of choice)
- Used for primary prophylaxis and prevention of recurring hemorrhage
- Alternative: injection sclerotherapy, absolute alcohol, and fibrin glue, as well as cyanoacrylate, to stop acute variceal bleeding
Balloon tamponade using a Sengstaken-Blakemore tube or Minnesota tube
- Indication: alternative treatment in case of extreme hemorrhage, unsuccessful endoscopic treatment, or ineffective hemostatic medication; consider in hemodynamically unstable patients until they can be stabilized
- Complication: risk of decubitus gangrene → prevention: deflation of balloon every 5 hours for 5 minutes
- Endoscopic band ligation (procedure of choice)
- Interventional radiologic treatment: See “ ” above.
- Primary prophylaxis
- Secondary prophylaxis
- Portal hypertensive gastropathy: gastrointestinal ulcers, or diffuse lower gastrointestinal bleeding
We list the most important complications. The selection is not exhaustive.