Neurocritical care of patients with central nervous system infections

Bacterial meningitis and viral encephalitis are life-threatening infections with high mortality rates. Patients who survive these infections often remain permanently disabled. Potential neurologic complications requiring careful attention include impaired consciousness, elevated intracranial pressure (ICP), hydrocephalus, stroke, and seizures. Systemic complications are also common and are frequently the immediate cause of death. The importance of emergent administration of appropriate antimicrobial therapy cannot be overstated, but critical care of these patients should focus not only on treatment of the underlying infection and its immediate complications but also on minimizing secondary brain injury. Given the increasing complexity of the diagnostic and therapeutic modalities available to manage central nervous system (CNS) infections, the involvement of neurocritical care units and neurointensivists may be particularly helpful in improving outcomes. It is our opinion that ICP measurement should be strongly considered in selected patients with CNS infections, particularly those who are comatose. Treatments for intracranial hypertension, specifically in the setting of CNS infection, are described in this paper. For bacterial meningitis, intravenous dexamethasone should be administered, beginning concomitantly with the initial dose of antibiotics, at least until Streptococcus pneumoniae can be excluded as a pathogen. Clinicians should maintain a high index of suspicion for nonconvulsive seizures. Deterioration in neurologic status should also prompt early use of CT or magnetic resonance angiography and venography to exclude cerebrovascular complications.