Defining acute mild head injury in adults: A proposal based on prognostic factors, diagnosis, and management

The lack of a common, widely acceptable criterion for the definition of tri vial, minor, or Mild head injury has led to confusion and difficulty in com paring findings in published series. This review proposes that acute head-i njured patients previously described as minor, Mild, or trivial are defined as "mild head injury," and that further groups are recognized and classifi ed as "low-risk mild head injury," "medium risk mild head injury," or "high -risk mild head injury." Low-risk mild injury patients are those with a Gla sgow Coma Score (GCS) of 15 and without a history of loss of consciousness, amnesia, vomiting, or diffuse headache. The risk of intracranial hematoma requiring surgical evacuation is definitively less than 0.1:100. These pati ents can be sent home with written recommendations. Medium risk mild injury patients have a GCS of 15 and one or more of the following symptoms: loss of consciousness, amnesia, vomiting, or diffuse headache. The risk of intra cranial hematoma requiring surgical evacuation is in the range of 1-3:100. Where there is one computed tomography (CT) scanner available In an area, f or 100,000 people or less, a CT scan should be obtained for such patients. If CT scanning is not go. readily available, adults should have a skull x-r ay and, if this shows a fracture, should be moved to the "high-risk" catego ry and undergo CT scanning. High-risk mild head injury patients are those w ith an admission GCS of 14 or 15, with a skull fracture and/or neurological deficits. The risk of Intracranial hematoma requiring surgical evacuation is in the range 6-10:100. If a CT scan is available for 500,000 people or l ess, this examination must be obtained. Patients with one of the following risk factors-coagulopathy, drug or alcohol consumption, previous neurosurgi cal procedures, pretrauma epilepsy, or age over 60 years are included in th e high-risk group independent of the clinical presentation.