Compression of brain tissue due to high intracranial pressure leads to which syndrome, typically presenting with hypertension, bradycardia, and altered respiratory pattern?

• A. Cushing's reflex
• B. Herniation syndrome
• C. Subdural hematoma
• D. Intracerebral hemorrhage

Answer: (D)

Compression of brain tissue from rising intracranial pressure triggers the Cushing reflex, also called the Cushing triad. This pattern—high blood pressure, slow heart rate, and irregular or altered breathing—reflects the brainstem’s response to reduced cerebral perfusion as ICP climbs. When ICP increases, cerebral perfusion pressure falls, and the body raises systolic blood pressure in a last-ditch effort to push blood through the narrowed system. The high blood pressure triggers baroreceptors that slow the heart, producing bradycardia. Brainstem involvement then leads to changes in respiration. This triad is a dangerous sign that the brain is under threat and that herniation may be imminent, making it an emergency to address ICP immediately.

Underlying causes like intracerebral hemorrhage or subdural hematoma can raise ICP, and herniation syndrome can follow if ICP continues to rise, but the specific syndrome described by the triad is the Cushing reflex.