A neurologic assessment tells the nurse where a problem is in the nervous system and whether the client is getting better or worse. The single most important point is trend: one set of findings means little until it is compared with the baseline and the previous check.

Principles that explain most findings

• Level of consciousness (LOC) is the most sensitive and earliest indicator of a change in neurologic status. Restlessness, new confusion, or needing a stronger stimulus to wake up often appears before pupil or vital sign changes.
• Motor pathways cross. The corticospinal (pyramidal) tract crosses at the lower medulla, so a lesion in one cerebral hemisphere weakens the opposite side of the body.
• Crossed findings point to the brainstem. A brainstem lesion can damage a cranial nerve nucleus on the same side (e.g., facial weakness of the whole half of the face) and the corticospinal tract before it crosses, causing weakness of the opposite arm and leg. Example: left facial weakness with right arm and leg weakness suggests a left brainstem (pontine) lesion.
• Upper vs. lower face. The upper face receives input from both hemispheres. A cortical stroke (upper motor neuron) weakens mainly the lower face on the opposite side and spares the forehead. A facial nerve (lower motor neuron) lesion, such as Bell palsy, weakens the entire same side of the face, including the forehead.
• Sensory tracts: the dorsal columns carry fine touch, vibration, and position sense (cross in the medulla); the spinothalamic tract carries pain and temperature (crosses within one or two segments of entering the cord). The cerebellum coordinates movement on the same side.

Upper vs. lower motor neuron signs

Glasgow Coma Scale (GCS) — three areas: eye opening, verbal response, motor response. Score range 3–15. Record each component (e.g., E2 V3 M5 = 10), not just the total.

• GCS 8 or less = severe impairment; the client may not protect the airway ("less than 8, intubate" is a common teaching rule).
• A drop of 2 or more points is a significant decline — notify the provider promptly. Any fall in the motor score, even 1 point, or a new pupil change must also be reported.
• Apply a central or peripheral pressure stimulus only when the client does not respond to voice. Decerebrate posturing indicates deeper (brainstem) dysfunction than decorticate posturing.

Levels of consciousness (descriptive): alert → lethargic (drowsy, arouses easily) → obtunded (arouses with difficulty, slow responses) → stuporous (responds only to vigorous or painful stimuli) → comatose (no purposeful response). Describe the stimulus used and the response rather than relying on a label alone.

Pupils

• Size (in mm), shape, equality, and reaction to light (direct and consensual). Normal: PERRLA (pupils equal, round, reactive to light and accommodation).
• The pupillary light reflex tests cranial nerves II and III and is a key brainstem sign in head injury.
• A new unilateral dilated, sluggish, or fixed pupil suggests compression of CN III from uncal herniation — an emergency. Bilateral fixed, dilated pupils indicate severe brainstem injury. Pinpoint pupils suggest a pontine lesion or opioid effect.

Cranial nerves — high-yield tests

Motor strength (manual muscle testing, 0–5 scale)

Also check pronator drift (arms extended, palms up, eyes closed): the weak arm drifts down and pronates — a sensitive sign of mild upper motor neuron weakness.

Reflexes

• Deep tendon reflexes graded 0 (absent) to 4+ (hyperactive with sustained clonus); 2+ is normal. Symmetry matters most — asymmetric reflexes are more significant than a uniformly brisk or diminished response.
• Babinski sign: stroke the lateral sole; upward toe and fanning of toes is abnormal once a child is walking (after about 12–24 months) and indicates an upper motor neuron lesion.

Cerebellar function

• Finger-to-nose, heel-to-shin, rapid alternating movements, gait.
• Cerebellar dysfunction: intention tremor (worse as the hand approaches a target), ataxia, dysmetria, wide-based unsteady gait, nystagmus.
• Romberg test checks position sense (dorsal columns), not the cerebellum primarily: the client stands feet together; swaying or falling when eyes close is positive. Stand close to prevent a fall.

Meningeal signs (meningitis, subarachnoid hemorrhage)

• Nuchal rigidity — resistance and pain on neck flexion.
• Kernig sign — with the client supine, flex the hip and knee to 90°, then extend the knee; pain and resistance in the hamstrings/back is positive.
• Brudzinski sign — passive neck flexion causes involuntary flexion of the hips and knees.
• These signs have limited sensitivity; their absence does not rule out meningitis.

Stroke-specific tools

• NIH Stroke Scale (NIHSS) — standardized, rapid scoring of consciousness, gaze, visual fields, facial palsy, limb strength, ataxia, sensation, language, dysarthria, and neglect. Used for suspected stroke, to guide reperfusion decisions, and to track change. Score 0–42; higher is worse.
• Prehospital screens: BE FAST (Balance, Eyes, Face, Arm, Speech, Time).

Lumbar puncture — nursing care

• Before: consent; the provider usually checks for signs of increased ICP or a mass lesion first (CT before LP when there is papilledema, focal deficit, new seizure, altered consciousness, or immunocompromise), because removing CSF with high ICP can cause herniation. Review anticoagulants and platelet count. Have the client void.
• Position: side-lying with knees drawn to the chest and chin tucked ("fetal" position), or sitting and leaning over a bedside table. The needle enters below the end of the spinal cord, usually at L3–L4 or L4–L5.
• Label CSF tubes in order and send promptly.
• After: monitor the puncture site for leakage or bleeding and check leg sensation and movement. Encourage fluids unless restricted. Prolonged flat bed rest is not proven to prevent headache; follow local orders.
• Post-LP headache is worse when upright and better lying flat; treat with fluids, analgesics, caffeine as ordered; persistent cases may need an epidural blood patch.

Normal CSF (adult): clear and colorless; opening pressure about 10–20 cm H₂O (up to about 25 in some references); WBC 0–5 cells/µL (mostly lymphocytes); protein about 15–45 mg/dL (0.15–0.45 g/L); glucose about 50–80 mg/dL (2.8–4.4 mmol/L), roughly 60% of blood glucose.

Neurologic assessment is a team process. The nurse performs serial checks at the ordered frequency and escalates changes; the provider orders imaging and definitive treatment.

• Baseline first, then serial checks — typically every 1–4 hours for unstable clients, and more often (for example, every 15 minutes) during and after thrombolysis for stroke.
• Handoff at the bedside: outgoing and incoming nurses assess together so that the same stimulus and the same interpretation are used.
• Rapid response or stroke team activation for a new deficit, a GCS drop of 2 or more, a new pupil change, or a seizure.
• Sedation: document drug and timing, because sedatives and opioids confound the exam. Brief sedation interruptions may be ordered to allow a neurologic check.

Listed in priority order.

1. Airway and breathing first
   • Clients with low GCS may lose airway reflexes; position side-lying or with the head of bed elevated, suction as needed, prepare for intubation when GCS is 8 or less or protective reflexes are lost.
   • Note respiratory pattern (Cheyne-Stokes, ataxic, apneustic) — changes can reflect rising pressure on the brainstem.
2. Detect deterioration early
   • Compare every check with baseline: LOC, GCS components, pupils, motor strength, speech, vital signs.
   • Report immediately: decreasing LOC, new unilateral pupil dilation, new weakness, new seizure, or Cushing triad (rising systolic pressure with widening pulse pressure, bradycardia, irregular respirations — a late sign).
3. Safety
   • Fall precautions for weakness, ataxia, visual field cuts, neglect, impulsivity, or confusion.
   • Seizure precautions when indicated.
   • Stand close during Romberg and gait testing.
4. Communicate effectively
   • For aphasia, use short questions, gestures, and yes/no methods; allow time to respond.
5. Procedure care
   • Prepare and support the client during LP, MRI, EEG, and angiography, and monitor afterward as above.

• Explain why frequent neurologic checks, including waking at night, are needed — to catch changes early.
• Before MRI: remove all metal; report implants, pacemakers, shrapnel, or pregnancy.
• Before EEG: shampoo hair and avoid hair products; follow instructions about caffeine and sleep deprivation; take usual medicines unless told otherwise.
• After LP: drink fluids if allowed; report severe headache when upright, fever, neck stiffness, drainage from the site, or new leg numbness or weakness.
• Teach families the warning signs of stroke (BE FAST) and to call emergency services right away.

• LOC is the earliest and most sensitive sign of neurologic change.
• GCS = eye opening, verbal, motor; range 3–15; ≤ 8 = severe, protect the airway.
• Pupillary light reflex = key brainstem sign; a new unilateral dilated pupil = herniation risk.
• Cortical lesions cause contralateral weakness; brainstem lesions can cause crossed findings (same-side face, opposite-side limbs).
• UMN lesion = increased tone, hyperreflexia, Babinski; LMN lesion = flaccid, areflexia, atrophy.
• Muscle strength 3/5 = against gravity but not resistance.
• Reflexes: 2+ normal; symmetry matters.
• Cerebellar damage = intention tremor, ataxia, same side.
• Kernig: hip and knee flexed to 90°, then extend knee → pain = meningeal irritation.
• NIHSS is the standard rapid scale for suspected stroke.
• LP: fetal position; CT first if increased ICP is suspected; post-LP headache improves lying flat.