Partial pressure of NH₃ in cirrhotic patients with and without hepatic encephalopathy.

Although the exact pathogenetic factor in hepatic encephalopathy is still unknown, ammonia is considered to be the major cause of neurotoxicity. However, previous studies on the relationship between ammonia and the severity of hepatic encephalopathy have yielded variable results. Since unionized ammonia is the only form of ammonia that is able to freely spread through the blood-brain barrier and cause cerebral dysfunction, we tested the...