13.1. Traumatic brain injury
Traumatic brain injury (TBI) is the most common and severe form of injury to the central nervous system. It occurs in 30-40% of victims with mechanical injuries and ranks first among the causes of death and disability caused by injuries.
Classification. Closed and open TBI are distinguished.
In c l o s e d T B I, while cranial bones and the brain sustain an injury, there may be no wounds of soft head tissues, or such wounds are accompanied by injury to epicranial aponeurosis.
Open TBI is an injury to the skull and brain, in which epicranial aponeu-rosis is damaged, or there are basal skull fractures accompanied by bleeding and liquorrhea (discharge of cerebrospinal fluid from the ear or nose). If the dura mater is intact, open TBI is considered impenetrable, if it is compromised, the injury is classified as penetrating. With open injuries, there is always a risk of infection of intracranial contents, which determines the tactics of treatment.
According to presence of an accompanying injury, TBI can further be classified into isolated injury, polytrauma (injury accompanied by mechanical damage to other organs and systems), and combined injury (when other injuring factors are at work: thermal, radiation, chemical factors). Development of shock aggravates the course of TBI significantly, affecting clinical presentations, making diagnosis difficult and disguising developing complications. In assessing the severity of TBI, one should also take into account possible alcohol or drug intoxication.
According to degree of severity we distinguish mild TBI (mild degree of concussion and brain injury), moderate TBI (of moderate severity) and severe TBI (severe cerebral contusion, diffuse axonal injury of the brain, compression of brain) (Fig. 13.1).