Hypoxic hepatitis: a challenging diagnosis

Hypoxic hepatitis (HH), one of the most common causes of acute liver injury, has a prevalence of up to 10% of admissions in intensive care units across the world. Inadequate oxygen uptake by the hepatocytes resulting in centrilobular necrosis associated with abnormally raised levels of the serum transaminases (ALT, AST) in patients with clinical history of cardiac, respiratory, or circulatory failures is the key feature of this condition. Abstracts, reviews, case reports, and research letters from various sources such as Pubmed, Proquest, Ovid, Google Scholar, and ISI Web of Knowledge dating from 1970 to 2011 were read and analyzed thoroughly. A study of 100 patients with HH, carried out from 2009 to 2010 at Tongji Hospital of Tongji University, Shanghai, People's Republic of China, is also documented. The contributing factors leading to HH are passive congestion, ischemia, and arterial hypoxemia of the liver. Ischemia/reperfusion injury also has a major role in HH. Some of its complications are spontaneous hypoglycemia, a high level of serum ammonia, and respiratory insufficiency due to hepatopulmonary syndrome. The therapy of HH lies mainly in the treatment of the main underlying causes, and this leads to the successful reversion of HH. The aim of this review is to present a simplified concept about the etiology, pathophysiology, mechanism, clinical manifestations, diagnosis, and treatment of HH.