Secondary Responses and Insults Increased Intracranial Pressure
The brain is composed of brain tissue, blood, and cerebrospinal fluid encased in a rigid skull. Through the processes of accommodation and compliance, the ICP is maintained at its normal level of 10-15 mmHg despite transient increases in pressure that occur.
Increased ICP is the leading cause of death from head trauma in clients who reach the hospital alive. It occurs when compliance no longer takes place.
As the ICP increases, cerebral blood flow decreases, leading to tissue hypoxia, a decrease in serum pH level, and an increase in CO2 levels. This process causes cerebral vasodilation, edema, and a further increase in the ICP, and the cycle continues.