Raised intracranial pressure in acute viral encephalitis

There is paucity of data evaluating intracranial pressure (ICP) rise and its management in acute viral encephalitis (AVE). Noteworthy is the current prevalence of unselective and broad utilization of ICP lowering therapies in clinical practice. Trends in current management of ICP in AVE emanate from data extrapolated from results of studies done on cerebral malaria, bacterial meningitis, stroke, and brain trauma patients. In this article we review (1) clinical correlates of raised ICP, (2) pathology, (3) imaging data, (4) monitoring, and, (5) treatment, of raised ICP in AVE. ICP monitoring is a useful adjunct to management of raised ICP in adults, becoming especially important in Herpes encephalitis and encephalitis with status epilepticus. In children it substantially influences clinical management and continuous monitoring of mean blood pressure (MBP) and ICP can aid in early diagnosis and treatment when cerebral perfusion pressure (CPP) falls below critical levels. Current evidence suggests that the pathomechanisms that contribute to the development of raised intracranial pressure vary in viral encephalitides of different etiology, and different forms of cerebral edema result at different times in the course of the illness, thus creating a need for studies to investigate the usefulness of various edema-specific ICP lowering modalities in AVE.