A patient recovering from head injury. Which activity demonstrates understanding measures to prevent elevation of intracranial pressure?

A patient recovering from head injury. Which activity demonstrates understanding measures to prevent elevation of intracranial pressure?

• A. Eating high-fiber foods rather than using enemas and laxatives
• B. Taking a hot bath daily
• C. Straining to have a bowel movement
• D. Breathing rapidly into a bag

Answer: (A)

Preventing rises in intracranial pressure is about avoiding anything that increases venous pressure or cerebral blood flow. Constipation can lead to straining during a bowel movement, which includes a Valsalva maneuver that markedly raises intrathoracic and venous pressure, reducing drainage from the brain and raising ICP. A high-fiber diet keeps stools soft and regular, minimizing the need to strain and helping maintain stable ICP. Other choices would tend to raise ICP or worsen cerebral perfusion: a hot bath can cause vasodilation and increased cerebral blood flow, potentially elevating ICP; straining to have a bowel movement directly increases intrathoracic pressure; and breathing rapidly into a bag raises CO2 levels, causing cerebral vasodilation and increased ICP.

Preventing rises in intracranial pressure is about avoiding anything that increases venous pressure or cerebral blood flow. Constipation can lead to straining during a bowel movement, which includes a Valsalva maneuver that markedly raises intrathoracic and venous pressure, reducing drainage from the brain and raising ICP. A high-fiber diet keeps stools soft and regular, minimizing the need to strain and helping maintain stable ICP.

Other choices would tend to raise ICP or worsen cerebral perfusion: a hot bath can cause vasodilation and increased cerebral blood flow, potentially elevating ICP; straining to have a bowel movement directly increases intrathoracic pressure; and breathing rapidly into a bag raises CO2 levels, causing cerebral vasodilation and increased ICP.