FACTORS OF SECONDARY ISCHEMIC CEREBRAL DAMAGE AT CRANIOCEREBRAL TRAUMA PART 2. GUIDELINES FOR CORRECTION OF THE SECONDARY CEREBRAL DAMAGE FACTORS
Current concepts of traumatic brain injury (TBI) pathogenesis are based on identifying the primary and secondary factors of cerebral damage. Primary cerebral damage is the result of a direct physical impact on the brain by a traumatizing agent, and is manifested by brain matter necrosis, damaged pathways and vascular wall in the area of brain injury. Secondary cerebral damage is inherently an evolutionary generated reaction that occurs in response to a primary mechanical injury. The secondary cerebral damage is induced at the moment of trauma and evolves over time causing an irreversible ischemic cellular damage in the area of primary injury and involving new intact cells in this pathologic process. The development of secondary cerebral damage considerably aggravates the severity of patients with TBI, impairs their mental and motor recovery, and increases the risk of adverse outcome. Factors contributing to the development of the secondary ischemic cerebral damage are divided into intracranial and extracranial. Intracranial factors include: intracranial hypertension, impaired cerebral hemodynamics, obstructive hydrocephalus, ischemia, cerebral edema, and dislocation syndrome. Extracranial factors of the secondary cerebral damage include: arterial hypotension, hypoxemia, hyperthermia, anemia, hyper- and hypocapnia, impaired water-electrolyte metabolism and energy metabolism. Preventing and restraining the effects of factors causing secondary ischemic cerebral damage, we can signifi cantly improve an outcome in severe TBI. Methods for the prevention and treatment of the secondary cerebral damage factors in severe TBI are subdivided into conservative and surgical. Conservative methods are usually used for the correction of extracranial factors of the secondary cerebral damage. Conservative treatment includes the following measures: the maintenance of an adequate cerebral perfusion and oxygenation, an intracranial pressure (ICP) reduction, the replacement of circulating blood volume (CBP), normocapnia maintenance, hyperthermia control, and spasm relief, the provision of nutritive support, the prevention and treatment of septic complications. Surgical treatment methods are usually used to eliminate intracranial factors of the secondary cerebral damage (intracranial hypertension, cerebral edema, obstructive hydrocephalus, and dislocation syndrome). The paper describes in detail the conservative and surgical methods of the prevention and correction therapy for the factors of secondary cerebral damage.