By definition, one speaks of portal hypertension when the pressure gradient between the portal vein and the inferior vena cava is greater than 12 mmHg. The normal gradient is equal to 5 mmHg. The causes of portal hypertension without hepatic cirrhosis are due either to an increase of portal blood flow or an increase in resistance to the portal flow. 

They are reported in the table below:

Table:  child portal hypertension causes without cirrhosis

Clinical signs are: 

-         a collateral circulation at the abdominal level;

-         a splenomegaly often accompanied by a hypersplenism with major low platelets count; 

-         esophageal and/or gastric varices, leading to GI bleeding;

-         sometimes a hepato-pulmonary syndrome (see this topic).

In case of pre-hepatic portal hypertension, the liver is small and atrophic.

Hepatopulmonary syndrome (see this topic) or pulmonary hypertension. Hepato-pulmonary hypertension (HPoP) develops in approximately 2 % of patients who have portal hypertension: this lung vascular damage could be due to the passage through the pulmonary circulation of toxic substances of splanchnic origin (perhaps associated residual activity of pancreatic enzymes) which escape the 'liver filter. These substances lead to specific abnormal pulmonary angiogenesis and the progressive development of intimal fibrosis, plexiform lesions and thrombosis (organized and recanalized) at the level of the pulmonary artery distal... HPoP diagnostic criteria are a mean PAP  > 25 mmHg at rest with high pulmonary resistance (> 240 dynes.s.cm5, instead of pulmonary hypertension associated with hyperdynamic circulation) and a  low occlusion pressure (contrary to a situation of hypervolemia). The HPoP is known as moderate when the mean PAP is > 35 mmHg and severe if it is > 45 mmHg. The symptoms are: the emergence of an effort dyspnea, palpitations, syncope. The diagnosis is made by transthoracic cardiac ultrasound (doppler) which must be done regularly in any patient with portal hypertension. The proposed treatments are prostacyclin, bosentan (but risk of liver toxicity), sildenafil. The presence of a HPoP is not an indication of liver transplantation ( the perioperative mortality of which is major in these cases ).

Medical treatment: β-blockers to reduce the cardiac output and thus the portal pressure, diuretics if ascites.

Surgical treatment: portal hypertension can be corrected by deriving the portal blood:

-         to the inferior vena cava:  porto-caval or meso-caval shunt;

-         to the left renal vein:Warren  spleno-renal shunt, rarely used nowadays;

-         mesenteric vein to the left side of the portal vein (Rex recessus): this technique, which is feasible only in case of pre-hepatic portal hypertension, has the advantage of restoring a portal flow in the liver, which restores the metabolic liver functions and provide intestinal trophic factors 

Anesthetic implications: 

check liver function and hemostasis (coagulation factors, low platelets, etc.); room air SpO2: suspect hepatopulmonary syndrome if SpO2 decreases by > 5 % from supine to upright position (orthodeoxia); cardiac ultrasound, for early diagnosis of pulmonary hypertension or hepatopulmonary syndrome. Portal hypertension makes all laparotomies hemorrhagic. In the event of thrombophilia, it is advisable to seek specialist advice: heparin therapy (AT3, protein S or factor V Leyden deficiency) or administration of fresh frozen plasma (protein C deficiency) during major surgery to correct the deficiency and avoid postoperative thrombotic events (shunt thrombosis, for example). Treatment with â-blockers ?

A laparoscopy in children with portal hypertension, with or without hepatic insufficiency, increases PaCO2 significantly more than in normal children. This increased absorption of CO2 is likely due to the collateral circulation at the level of the peritoneum, the increase in cardiac output and the increased arterial flow at the splanchnic level    

References : 

-         Bozkurt P, Kaya G, Yeker Y et al. 
Arterial carbon dioxide markedly increases during diagnostic laparoscopy in portal hypertensive children. 
Anesth Analg 2002; 95:1236-40.

-        Mack CL, Superina RA, Whitington PF. 
Surgical restoration of portal flow corrects procoagulant and anticoagulant deficiencies associated with extrahepatic portal vein thrombosis. 
J Pediatr 2003; 142:197-9.

Updated: May 2015