Hepatopulmoner Sendrom

 

Hepatopulmonary syndrome (HPS) is characterized by the triad of abnormal arterial oxygenation caused by intrapulmonary vascular dilatations (IPVDs) in the setting of liver disease, portal hypertension, or congenital portosystemic shunts

HPS is most commonly seen in patients with chronic liver disease, particularly those with portal hypertension

●Chronic liver disease – Chronic liver disease (CLD) of virtually any etiology including congenital liver disease that limit venous flow to the lung (eg, cavopulmonary shunt) and Abernethy malformation (congenital portosystemic shunt) can be associated with HPS, particularly when CLD is complicated by portal hypertension.

●Portal hypertension – HPS is most commonly seen in patients with portal hypertension in association with chronic liver disease but can also occur in those who have portal hypertension without underlying liver disease

In patients with liver disease, no risk factors other than the presence of portal hypertension are known to predispose to the development of HPS.

HPS may coexist with other pulmonary disease (eg, chronic obstructive pulmonary disease) and, in particular, portopulmonary hypertension, which may aggravate hypoxemia

HPS should be suspected in patients with chronic liver disease who have dyspnea, platypnea/orthodeoxia, spider nevi, and/or evidence of impaired oxygenation, such as a peripheral arterial oxygen saturation <96 percent.

Chest imaging (ie, chest radiography and computed tomography) and a low diffusing capacity on pulmonary function testing are not diagnostically helpful but are typically performed since they help to exclude alternate causes of dyspnea and hypoxemia and narrow the differential.

Additional diagnostic testing usually focuses on the objective demonstration of impaired oxygenation and the presence of shunt from intrapulmonary vascular abnormalities (IPVDs) using the following:

Oximetry and arterial blood gas (ABG) analysis

Transthoracic contrast echocardiography (TTCE) -

TTCE is usually sufficient to demonstrate the presence of an intrapulmonary shunt supportive of underlying IPVDs

 TTCE is the test of first choice for the evaluation of a right-to-left shunt due to suspected IPVDs because it is more sensitive than other methods and less invasive than pulmonary arteriography

 In patients with liver disease, detection of an intrapulmonary right-to-left shunt by TTCE ("bubble study") is strongly suggestive of IPVDs. TTCE is performed by injecting contrast material (usually agitated saline) intravenously during echocardiography.

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