The hepatopulmonary syndrome is characterized by defects in oxygenation due to pulmonary abnormalities associated with chronic liver disease.
Hepatic findings — Most patients with HPS have symptoms and signs of chronic liver disease. These may include weakness, fatigue, anorexia, ascites, a large or small liver, splenomegaly, spider angiomata, palmar erythema, jaundice, asterixis, anasarca, nail changes, digital clubbing, hypertrophic osteoarthropathy, caput medusae, gynecomastia, and testicular atrophy Platypnea – Platypnea is an increase in dyspnea that is induced by moving into an upright position and relieved by recumbency.Orthodeoxia – Orthodeoxia refers to a decrease in the arterial oxygen tension (by more than 4 mmHg [0.5 kPa]) or arterial oxyhemoglobin desaturation (by more than 5 percent) when the patient moves from a supine to an upright position, which is improved by returning to the recumbent position. The presence of orthodeoxia in a patient with liver disease is strongly suggestive of HPS, although it can be seen in other situations (eg, post-pneumonectomy, recurrent pulmonary emboli, atrial septal defects, and chronic lung disease) [ 18 ]. Orthodeoxia affects up to 88 percent of patients with HPS, compared to 5 percent or fewer of patients with cirrhosis alone
The presence of orthodeoxia in a patient with liver disease is strongly suggestive of HPS, although it can be seen in other situations (eg, post-pneumonectomy, recurrent pulmonary emboli, atrial septal defects, and chronic lung disease)
Mechanisms of Arterial Hypoxemia in the Hepatopulmonary Syndrome in a Two-Compartment Model of Gas Exchange in the Lung
agitated saline (forms a stream of microbubbles 60 to 150 microns in diameter)