Acute coma

The approach to a comatose patient should be organized and initially focused on treatable causes. Having a checklist (written or just mental) is very useful to avoid missing possible diagnoses or tests that should be conducted. On the other hand, indiscriminate testing is ill-advised because it can result in misdiagnosis from false-positive results in addition to sometimes exposing the patient to unnecessary risks and increasing costs of care. Empiric treatment is sometimes indicated, such as in the case of possible bacterial meningitis or HSV-1 encephalitis, until certain diagnoses can be excluded. Prognosis depends on diagnosis and should generally not be discussed before a diagnosis is established. This chapter provides a brief overview and practice recommendations for the diagnosis, treatment, and prognosis of the most common causes of acute coma in adult patients.