Hepatopulmonary syndrome in children-an update

Hepato-pulmonary syndrome (HPS) is an uncommon complication of liver disease. It can be acute or chronic and occur with or without portal hypertension. The reported frequency of HPS in patients with liver disease ranges between 4% and 32%. It occurs as a result of vasodilatation of the pulmonary vasculature which is most likely to be mediated by nitric oxide (NO). Three components are essential to the definition of HPS: 1. liver disease, 2. intra-pulmonary vascular dilatation (IPVD) and 3. impaired oxygenation. .Disease severity is determined by quantifying the degree of oxygenation impairment. Contrast enhanced echocardiography (CE-TTE) and Tc-99 labeled macro-aggregated albumin lung scan with uptake in brain are the gold standard investigations to diagnose HPS and plan management. Clinical features which are characteristic of HPS include orthodeoxia and platypnea in the presence of liver disease. Although there are anecdotal reports on the use of several drugs in the medical management of HPS, none have been shown to result in either sustained improvement in oxygenation or reduce mortality. Liver transplantation is possible and no longer considered to be contraindicated in HPS. However it is important to carefully select and prioritize patients with HPS for liver transplantation for optimum results.