Review article: hepatic hydrothorax

Patients with cirrhosis and portal hypertension often have abnormal extracellular fluid volume regulation, resulting in accumulation of fluid as ascites, oedema or pleural effusion. These complications carry a poor prognosis with nearly half of the patients with ascites dying in the ensuing 2-3 years. In contrast to what happens in the abdominal cavity where large amounts of fluid (5-8 L) accumulate with the patient only experiencing only mild symptoms, in the thoracic cavity smaller amounts of fluid (1-2 L) cause severe symptoms such as shortness of breath, cough and hypoxaemia. Hepatic hydrothorax is defined as a pleural effusion, usually >500 mL, in patients with cirrhosis without cardiopulmonary disease. The pathophysiology involves the direct movement of ascitic fluid from the peritoneal cavity into the pleural space through diaphragmatic defects. The estimated prevalence among cirrhotic patients is 5-10%. The effusion, which is a transudate, most commonly occurs in the right hemithorax. The mainstay of therapy is similar to that of portal hypertensive ascites and includes sodium restriction and administration of diuretics. Refractory hydrothorax can be managed with transjugular intrahepatic portosystemic shunt in selected cases. Pleurodesis is not routinely recommended. Suitable patients with hepatic hydrothorax should be considered candidates for liver transplantation.