EPIDEMIOLOGY

Traumatic brain injury (TBI) is a major cause of morbidity, mortality, and healthcare expense in the United States and Europe. Each year approximately 1 million head-injured patients are treated and released from United States emergency departments (EDs). The incidence rate of hospitalized plus fatal TBI in the United States (103 per 100,000 population) is considerably lower than in Europe (235 per 100,000 population). The mortality rate remains similar for the United States and Europe (15–20 per 100,000 population/year).

1. ▪In the United States, transportation-related crashes (involving motor vehicles, bicycles, pedestrians, and recreational vehicles) accounted for 49% of all TBIs; falls accounted for an additional 26% and firearm use (including suicide attempts) accounted for 10% of all TBIs.

2. ▪In Europe, transportation-related crashes are still the main cause of injury. However, falls represents approximately 40% of injuries and violence/ assaults fewer than 5%.

CLASSIFICATION OF TBI

The Glasgow Coma Scale (GCS; Table 16.2) is widely used to evaluate the severity of brain injuries. This scale corresponds to the definition of coma as no eye opening (E < 2), no verbal utterances (V < 3), and not following commands (M < 6). However, the assessment of the components of the GCS is limited by widespread use of sedation and intubation before hospital arrival.

1. ▪TBI is stratified according to the GCS score as mild (scores 14–15), moderate (9–13), or severe (3–8).

2. ▪Increased severity of injury on admission is associated with an increased rate of death or vegetative state and a decreased rate of good recovery.