What does "rubbing the sternum" test for in an unresponsive patient?

"Rubbing the sternum," also known as a sternal rub, is a technique used to assess a patient's response to painful stimuli, which helps determine their level of consciousness. When applied, this method stimulates the nerves in the area and elicits a response if the patient is capable of reacting to discomfort.

In unresponsive patients, this physical stimulus can reveal whether the patient is in a state of altered consciousness, such as being in a deep sleep or more serious conditions like a coma. If the patient reacts to the sternal rub by moving, groaning, or opening their eyes, it provides critical information about their neurological status and overall responsiveness.

The other options focus on different types of responses. A response to verbal commands would assess cognitive function rather than a physical reaction to pain. The ability to follow simple commands also evaluates cognitive and auditory comprehension, and response to light touch tests for a more general awareness of sensation, rather than a specific pain response. Therefore, "rubbing the sternum" directly tests for pain response and helps gauge the individual's level of consciousness effectively.