Impaired consciousness

Assessing disordered perception of self and the environment can indicate a potentially dangerous disruption in brain, respiratory, circulatory, or metabolic function. Clinicians typically assess consciousness through conversation and examination of gaze and reflexes. To determine a person’s consciousness, they ask them a simple question like their name or how they feel and request a specific action such as extending their hand or touching their nose.

It’s possible to mistake disturbances of consciousness for sleep, so if there’s doubt, the common approach involves audibly calling the person by name or asking them to open their eyes. If the person fails to respond, physical contact such as shaking their hand or gently pinching the skin is typically the next step. When the person cannot awaken, clinicians may test gaze and knee reflexes.

We can categorize disturbances in consciousness into four degrees:

1. Disoriented orientation – A decrease in consciousness level where the individual can still converse but responds to questions slowly, exhibiting disturbed self-awareness and perception of time and place.

2. Stupor – The person experiences deep sleep and upon awakening, responds incoherently and off-topic to questions.

3. Sopor – The individual is in unarousable sleep, but gaze and knee reflexes persist.

4. Coma – The person remains in unarousable sleep with absent gaze and knee reflexes.