Neurological Assessment

A patient's pupils are equal and reactive, but they can't squeeze both your hands equally. You almost missed a stroke — because you stopped at the cranial nerves.

A complete neurological assessment has four components: mental status (level of consciousness, orientation, speech), cranial nerves (I–XII), motor/sensory function, and reflexes. Level of consciousness is the most sensitive indicator of neurological change — it deteriorates before vital signs do. Use the Glasgow Coma Scale (GCS) to standardize LOC: Eye opening (1–4), Verbal response (1–5), Motor response (1–6), total range 3–15. A GCS of 8 or below typically indicates coma and inability to protect the airway. Pupil assessment includes size (2–6 mm normal), shape (round), equality, and reactivity to light — both direct and consensual responses. A fixed, dilated pupil signals increased intracranial pressure on the ipsilateral side. Motor strength is graded 0–5 bilaterally; asymmetry matters more than absolute score because unilateral weakness localizes a lesion. Assess orientation in order of loss: time goes first, then place, then person. Document changes from baseline, not just a snapshot — trending is what catches deterioration early.

Key Distinctions

Don't confuse GCS motor response (best response to stimuli, scored 1–6) with muscle strength grading (0–5 scale for voluntary movement) — they measure different things and use different scales. Students often assess orientation as simply "alert and oriented x3" without specifying which spheres are intact. A sluggish pupil is not the same as a nonreactive pupil — sluggish is early warning, nonreactive is emergency.

Clinical Pearl

LOC drops before vitals crash. If the patient who was talking to you five minutes ago now won't open their eyes, don't wait for the blood pressure to confirm what you already know.