Which activity could most disrupt readings of an intracranial pressure monitor during physical therapy?

• A. Having a snack in the room
• B. Reading the monitor
• C. Turning off the monitor
• D. Changing the bed height

Answer: (D)

Intracranial pressure readings are highly sensitive to position and the resulting effects on cerebral venous drainage and arterial inflow. When you change the bed height, you alter head and neck alignment relative to gravity and the heart, which changes venous outflow from the brain and can quickly shift ICP. Even a small adjustment in bed height can cause a noticeable fluctuation in the monitor readings, making the data harder to interpret during therapy.

The other actions don’t physiologically shift ICP in the moment: snacking in the room doesn’t affect brain pressure, simply reading the monitor doesn’t change the physiology, and turning off the monitor would stop data entirely rather than reflect a change in intracranial dynamics. So, changing bed height is the most disruptive to ICP readings during physical therapy.