Neuroscience nursing is challenging, and, possibly due to the lack of measurable criteria, it may be frightening. "I know he's not behaving quite like he did an hour ago" is so much harder to defend to a neurologist than "his systolic blood pressure has increased 50 mm Hg in the last ..." Learning and practicing the following assessment techniques may give you the ability to define those subtle clinical changes and more confidence in your assessment skills.
An accurate, focused neurologic assessment, while not difficult, does require consistency and attention to detail. Consistency helps develop assessment skills and assures no steps are missed. A thorough assessment is vital to quickly recognize changes. In order to maintain consistency you should complete a thorough assessment with the nurse from whom you receive report. No matter how well trained the nurse, some parts of an assessment are subjective and should be verified together. A focused neurologic assessment should be performed in a systematic head-to-toe manner, and includes the Glasgow Coma Scale (GCS), cranial nerve assessment, muscle strength and coordination. Balance and reflexes are also assessed, but usually by the healthcare provider and based on the patient's clinical status.1,2
The GCS is a rapid assessment tool developed to objectively assess level of consciousness (LOC), but it can't detect finer changes in neurologic status. (See Glasgow Coma Scale.)
Mental status
Early clues to neurologic deterioration include forgetfulness, new-onset agitation or restlessness, or other changes in LOC. Assessing the awake patient begins with entering the room and introducing yourself. While you observe the patient's general appearance and behavior, ask his or her name, location, date, and situation.3 Begin with general and move to more precise data, such as "tell me the year, now the month, and today's date." After a stay in the hospital it's easy for patients to forget which day it is. If your patient requires a reminder of the day and later in the interaction you ask again what day it is and he gets it right, score the patient as oriented. Beware the trap of asking the exact same questions each time! Patients could be confused, but learn to answer these by rote, and you may miss a change. Avoid asking yes/no questions, as the patient may guess right, leading to inaccurate assessment data. Often the first signs of neurologic deterioration are subtle changes in LOC and are best detected during conversation, or by family members. If the patient's spouse or partner tells you the patient is "different," he's different.
Early in your assessment give the patient three unrelated words to remember (such as apple, dog, and house). Ask the patient to repeat the words to confirm that they were heard and understood, which assesses immediate recall. After about 3 to 5 minutes, ask the patient to repeat the words again to assess new learning ability. In conversation with the patient, you can assess short-term memory by asking who visited recently or what the patient had for breakfast, as long as you can verify that the patient's responses are accurate. Assess remote or long-term memory by asking how long he or she has been married, place of birth, or other information you can verify in the medical record or through family members. Recognition of family members or visitors, or even staff members who are frequently in the room can be done easily. "Would you introduce me to your visitor?" will prompt a response while not appearing clinical. Patients who need frequent neurologic assessments will become tired and frustrated with the repetition, especially at night when they're awakened. Change the questions and make it as conversational as much as possible.
Assess your patient's attention span by how well he or she gets "back on track" during conversations. You can also say a five-letter word, spell it, and ask the patient to spell it backward. Use simple math problems to assess your patient's calculating ability, such as asking, "What is 4 + 3?" Take into consideration your patient's literacy level, medications, and other factors that affect the ability to perform arithmetical calculations. Focus on topics that interest your patient, such as sports, politics, or TV programs when assessing higher cognitive functions.
Cranial nerve assessment
Next, assess cranial nerve function. Your patient is following commands if he's able to assist you in any of the cranial nerve assessments. "Give me a thumbs up" works for even the barely conscious patient and determines the ability to follow and understand commands. (See Reviewing cranial nerve function)
Cranial nerve I-olfactory. The sense of smell isn't often assessed in a hospital environment, but if indicated, use a familiar and nonirritating odor, such as coffee. First, confirm patency of each nasal passage by asking the patient to occlude one nare, while inhaling through the other. Test each nare separately after asking the patient to close both eyes and ask if the patient can smell anything and identify it. Avoid irritating and noxious odors such as ammonia.
Cranial nerve II-optic. Assess visual acuity by asking your patient to read any available print such as your name badge or a newspaper, but be sure he's wearing reading glasses or contact lenses normally worn.
Cranial nerves II and III-optic and oculomotor. Test the pupillary reactions to light in a darkened room if possible, one eye at a time. Ask the patient to look into the distance and shine a bright light obliquely into each pupil. Look for the direct reaction (pupillary constriction in the same eye) and the consensual reaction (pupillary constriction in the opposite eye).
Cranial nerves III, IV, and VI-oculomotor, trochlear, and abducens are assessed together as extraocular movements (EOMs) in the six cardinal directions of gaze. Instruct your patient to follow your finger with her eyes, while holding her head still. Make a wide H in the air and lead her gaze to her extreme right, to the right and upward, and down on the right; then without pausing in the middle to the extreme left, to the left and upward, and down on the left.
Cranial nerve IV allows a patient to look toward his nose, cranial nerve VI toward his ear, and cranial nerve III controls the remaining EOMs.
Cranial nerve V-trigeminal. Palpate the temporal and masseter muscles in turn while asking the patient to clench her teeth. Then with the patient's eyes closed, test for light touch by using a fine wisp of cotton and touching her forehead, cheeks, and jaw on each side.
Cranial nerve VII-facial. Ask your patient to raise his eyebrows, frown, close both eyes tightly so that you can't open them, show both upper and lower teeth, smile, and puff out both cheeks.
Cranial nerve VIII-acoustic. Hearing can be assessed during conversation, but to detect a deficit in one ear rub your fingers together next to both of your patient's ears and ask if the sound is the same on both sides.
Cranial nerves IX, X, and XII-glossopharyngeal, vagus, and hypoglossal. Listen to the patient's voice and articulation. Ask your patient to stick out his tongue and say "ahhh," while you watch the movements of the soft palate and pharynx. Is the uvula midline? Assess swallowing ability and the gag reflex. Inspect the tongue for midline position, or atrophy. Assess the patient's ability to move the tongue from side to side. Deficits in cranial nerve XII may also be observed if the patient is unable to clearly articulate D, L, N or T sounds.
Cranial nerve XI-spinal accessory. Ask the patient to shrug both shoulders upward against your hands and turn her head to each side against your hand.
Assess muscle strength by asking the patient to move actively against your resistance or to resist your movement. Commands given to assess the muscle strength in the upper extremities include testing flexion and extension at the elbow by having the patient pull and push against your hand. The most common scale for grading muscle strength is the Medical Research Council Scale for Muscle Strength.4,5 Use the grading system used in your facility for continuity. (See Grading Muscle Strength)
Assess for pronator drift by asking the patient to close both eyes and hold both arms straight forward, palms up, as if holding an imaginary pizza box for 5 seconds. Downward drift of one arm, with or without forearm pronation, indicates weakness.
Assessing muscle strength of the lower extremities includes testing flexion at the hip by placing your hand on the patient's shin and asking the patient to raise his leg against your hand. Assess dorsiflexion and plantar flexion at the ankle by asking the patient to pull up and push down against your hand, to "push on the gas" and point her toes toward her nose.
Assess coordination of muscle movement by assessing point-to-point movements. Ask the patient to touch your index finger and then his nose alternately several times, while you move your finger each time. Assess rapid alternating movements by asking the patient to strike one hand on her thigh, raise the hand, turn it over, and then strike the back of her hand down on the same place as rapidly as possible. Lower extremity coordination may be assessed by having the patient lift one leg and slide the heel down the shin of the other leg, or tap your hand as with the great toe of each foot in turn. Remember, we're all less coordinated with our feet compared with our hands!
The unresponsive patient
Assessing the unresponsive patient is more challenging, but is even more vital as signs of neurologic deterioration are easier to miss. In assessing these patients, the GCS is helpful.
Appropriate methods of assessing response to noxious stimuli include sternal rub, trapezius squeeze, supraorbital pressure, and mandibular pressure.6 A sternal rub is best performed without causing friction to the skin, but may cause ecchymoses even when properly performed. Explain to family members what you're doing and why beforehand. The trapezius muscle lies between the neck and shoulder, and you must grab and pinch at least 2 in (5.08 cm) to assure you have muscle, not just skin. Supraorbital pressure is achieved by pressing upward into the notch in the orbital bone above the eye. Mandibular pressure is upward pressure at the angle of the jaw. Perform each of these on yourself to the point of mild pain in order to best understand what you're doing to your patient and what response to expect.
The above methods of applying a central pain stimulus should induce a global response; each extremity should respond. If you see that one extremity doesn't respond you can apply a peripheral pain stimulus to that extremity. Nailbed pressure may induce a spinal response, and you can inform the healthcare provider that global response was negative but the spinal response was positive. This helps in determining the cause of new changes. Inappropriate methods of eliciting a pain response include nipple twisting or pinching the inner aspect of the arm or thigh. While ecchymoses is possible when utilizing the appropriate methods, rotation of sites may help reduce its incidence.
Some cranial nerve functions can be assessed in the unresponsive patient. Testing the pupillary light reflex in each eye will evaluate cranial nerves II and III. EOMs can be evaluated by assessing eye position noting the presence of deviation such as persistent lateral and downward eye deviation. Horizontal eye movements can be assessed by the oculocephalic maneuver (doll's eyes) and vertical eye movements can be assessed by moving the head and neck vertically. Assess cranial nerves V and VII by testing the corneal reflex. The sensory limb of this reflex is carried in cranial nerve V, and the motor response in cranial nerve VII. Cranial nerves IX and X can be tested by assessing the gag reflex.
Assess motor response in each limb, using painful stimuli if necessary. Localizing includes crossing the midline, approaching the stimulus, or pushing your hand away. Withdrawing from the stimulus is a passive response. Note any abnormal flexion (decorticate) or extension (decerebrate) posturing. Always compare the left side of the body to the right and grade muscle strength whenever possible.
Developing your assessment skills
Remember to incorporate the family as well as your knowledge of medications and treatments that may influence neurological response. If the patient has recently received pain medication, sedation or medication with sedative side effects you may have to put forth a little more effort to obtain the same responses. Also things like ventilator weaning trials may tire a patient, emotional visits, time of day or even accumulated hours of frequent neurological exams impairing sleep may affect the response you obtain. An older patient will have slowed responses and may have deficits related to age instead of an acute neurological change.6
If you use the above process consistently, you'll develop your neurologic assessment skills to the point that you can approach a neurosurgeon or neurologist with confidence, describe a neurologic change you noted, and assure the best possible care for your patient.
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