The treatment of mass lesions such as hematoma or tumor is their surgical removal as rapidly as possible before herniation and significant damage to other structures occurs. Treatment for patients with closed-head injury and patients who have undergone extensive surgical procedures on the brain utilize the same principles. Controlled respiration, steroids, and the control of ICP are the principal techniques although other treatments have been introduced recently. Controlled respiration assures an adequate O2 delivery to cells that are much more susceptible to anoxia after injury. Regulating the pCO2 adjusts the size of the vessels and intracranial volume in the uninjured brain and, thus, affects the intracranial pressure. This effect is however not long lasting and may have undesirable side effects if used over extended time period and is used for only short period of time during the most acute period.
Intravenous administration of large doses of steroids is used routinely in the treatment of brain tumors although its effectiveness in clinical trials of head trauma has not been demonstrated convincingly. It is aimed at improving the function of the injured cells by stabilizing their membranes and by decreasing the edema around the tumor. While steroids cannot be expected to restore the integrity of anatomically destroyed cells, they improve the function of cells at the periphery of the lesion and probably secondarily the microcirculation.
The administration of mannitol intravenously leads to a significant acute decrease in ICP which is useful as a temporary measure prior to a surgical removal of a mass lesion and during certain types of elective brain surgery. Its effectiveness in more chronic treatment of closed-head trauma is debated although it often is used empirically. Osmotic decrease in cellular and extracellular water in the uninjured brain, the prevention of secondary ischemic changes in the injured parts by decreasing intracranial pressure, changing the ionic milieu in the extracellular space, improving the perfusion, and decreasing the blood viscosity all have been suggested but the mode of action has not been fully defined.
The use of furosemide and other diuretics that affect the Na+/K+ pump action is based on their direct diuretic effect and on the laboratory-documented effect of decreasing the amount of cellular swelling induced by the elevated extracellular level of K+. Furosemide is used routinely in some centers, but its role in the treatment of closed-head injury is not well defined.
The use of high dose barbiturates or "barbiturate coma" has been advocated on the basis of their ability to decrease intracranial pressure and cerebral metabolic demand. Since barbiturates also have many other effects, their action may be through several other mechanisms as well. Despite great potential, their effectiveness in severe head trauma has not been demonstrated convincingly and they probably should not be used routinely at present without precise laboratory and EEG monitoring.
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