Chapter 6: Assessment and Observation of the Neurologic System

Introduction

The neurologic system is fundamental in controlling the body's functions, and in enabling responses (both automatic and voluntary) to external and internal stimuli. It is important that nurses are able to accurately and comprehensively assess this system, and this chapter introduces the fundamental knowledge and skills nurses require to do so. It begins with an overview of the fundamental anatomy and physiology of the neurologic system. The chapter then explains the processes involved in collecting a general health history for the neurologic system, and in performing a physical examination of the neurologic system. Finally, this chapter considers a number of special observation and assessment techniques which may be used in the physical examination of the neurologic system, and it discusses performing differential diagnosis relevant to the neurologic system.

Important note

This section of the chapter assumes a basic knowledge of human anatomy and physiology. If you feel you need to revise these concepts, you are encouraged to consult a quality nursing textbook.

Fundamental anatomy and physiology of the neurologic system

The neurologic system, comprised of the nervous systems, controls: (1) all the body's functions, and (2) responses, both automatic and voluntary, to external and internal stimuli. There are three divisions of the neurologic system:

1. The central nervous system, comprised of the brain, spinal cord and protective structures (e.g. cerebrospinal fluid).
2. The peripheral nervous system; a system of nerves which regulates the body's response to external stimuli. The peripheral nervous system is comprised of twelve pairs of cranial nerves and thirty-one pairs of spinal nerves, each controlling a different part of the body. As you will see in a later section of this chapter, the twelve pairs of cranial nerves are particularly important in the physical examination of a neurologic system; review the following information about these nerves:

3. The autonomic nervous system; another system of nerves which regulates the body's internal environment (in conjunction with the endocrine system).

Neurologic system - focused health history

As you have seen in previous chapters of this module, health observation and assessment involves three concurrent steps:

When assessing a patient's neurologic system, the nurse must commence by collecting a health history. This involves collecting data about:

In some cases, a person will present with a specific problem related to their neurologic system (e.g. headache, dizziness, seizures, loss of conscious, changes in movement [e.g. weakness, tremors, incoordination], changes in sensation [e.g. tingling, numbness], dysphagia, aphagia, etc.). Remember, nurses assess a patient's symptoms using the strategy remembered by the 'OLD CARTS' mnemonic (introduced in a previous chapter of this module).

Neurologic system - physical examination

Once a health history of the neurologic system has been obtained, as described in the previous section of this chapter, a nurse may commence a physical examination of the patient's neurologic system. A stepwise process of physically examining the patient's neurologic system, with normal (expected) and common abnormal findings, is presented in the following table:

When physically assessing a client's neurologic system, it is important for a nurse to note that there are a number of important age-related differences. You will study age-related differences in assessment in detail in a later chapter of this module; however, for now, consider these age-related differences specific to the assessment of the neurologic system:

• This section of the chapter identified a number of key reflexes which should be assessed in adults; however, a number of unique reflexes are assessed in infants (e.g. the Moro reflex).
• When undertaking a physical assessment of the neurologic system in older adults, nurses should be aware of normal age-related declines in physical functionality; these may impair a client's capacity to perform some parts of the assessment, but do not necessarily indicate problems with the neurologic system.

As you saw in a previous section of this unit, once a health history and physical examination have been completed, they should be documented so that the data collected can be used to: (1) assess the patient's condition, and (2) inform the care which is appropriate for that patient. Review the following example of how the findings from a physical examination of the neurologic system are documented (in this case, all the assessment findings are normal):

Special assessment techniques for the neurologic system

There are a number of special assessment techniques particular to the neurologic system; these will be explored in greater detail in this section of the chapter.

In some cases, when performing a physical examination of the neurologic system, a nurse may identify the need to test the function of one or more of the cranial nerves. This is done following:

• CNI (olfactory nerve): the nurse should ask the client to close their eyes, occlude one nostril, and then ask a client to identify a common aromatic substance held under their nose (e.g. coffee, peppermint toothpaste, citrus, etc.).
• CNII (optic nerve): the client should be referred to an ophthalmologist or optometrist for an evaluation of their visual acuity. If a nurse has appropriate training, they may complete this test themselves using Snellen's chart.
• CNIII (oculomotor nerve), CNIV (trochlear nerve) and CNVI (abducens nerve): the client should be asked to move their eyes left-right, up-down and obliquely.
• CNV (trigeminal nerve): the patient should be asked to clench their teeth, and the nurse palpates the temporal and master muscles for mass and strength. The nurse should then ask the patient to close their eyes and lightly touch the patient's forehead, nose and jaw, ensuring the client can feel sensation equally over these areas.
• CNVII (acoustic nerve): the client should be referred to an otologist for an evaluation of their hearing. If a nurse has appropriate training, they may complete a Rinne test themselves using a tuning fork.
• CNIX (glossopharyngeal nerve): the nurse should apply small quantities of salt, sugar and lemon to the client's anterior and posterior tongue, and ensure the client can differentiate between the salty, sweet and bitter tastes.
• CNX (vagus nerve): the nurse should ask the client to open their mouth and say 'ah', and observe the movement of their soft palate (upward) and uvula (bilaterally).
• CNXI (spinal accessory nerve): the patient should be asked to shrug their shoulders upwards against the nurse's hands, with the nurse observing for strong and symmetric contraction of the trapezius muscles.
• CNXII (hypoglossal nerve):  the nurse should ask the client to protrude their tongue, and move it left-right and up-down.

As described in the above table, in addition to evaluating the cranial nerves it is important that the nurse assesses the peripheral nerves. This is done by:

• Asking the client to close their eyes, and using a cotton ball to apply superficial light touch to an area of the client's extremities (e.g. the underside of their foot). The client should be able to determine the location and type of touch.
• Asking the client to close their eyes, and using a moderately sharp object (e.g. a broken tongue blade) to touch to an area of the client's extremities. The client should be able to determine the location and type of touch.
• Asking the client to close their eyes, and using a vibrating object (e.g. a tuning fork) to touch to an area of the client's extremities. The client should be able to determine the location and type of touch.
• Asking the client to close their eyes, before grasping one of the client's finger / toe and moving it upwards or downwards. The client should be able to determine: (1) which toe was moved, and (2) the direction in which it was moved.

As described in the above table, it is necessary that a nurse assess a client's cerebellar function for balance and coordination. This can be done in a variety of different ways, depending on the client's age and overall physical ability - for example:

• Romberg's test: the client should be asked to stand with their feet together, arms resting at their sides and their eyes closed. The client may sway slightly, but their foot position and upright posture should be maintained. When performing this test, the nurse should stand close to the client to steady them, if required.
• The client should be asked to stand on one foot, and then on the other; they should be able to maintain each position for at least 5 seconds. The client should then be asked to hop from one foot to the other; they should have sufficient muscle strength, coordination and balance to accomplish this task.
• The client should be asked to walk heel-to-toe (i.e. placing the heel of one foot directly in front of the toes of the other); they should be able to walk in this way in a straight line for some distance.
• The client should be asked to hold their arms out in front of their body, and perform several knee-bends (which may be shallow or deep); they should have sufficient muscle strength, coordination and balance to accomplish this task.
• The client should be asked to walk on their toes, and then on their heels; the client should be able to walk several steps on both their toes and their heels.
• The client should be asked to sit, place their hands on their knees, and rapidly move their hands so their palms are alternately up and down; the client should be able to maintain a rapid pace with good coordination throughout this activity.
• The client should be asked to sit, close their eyes, and use each index finger to rapidly touch their nose. The client should then be asked to open their eyes and move their finger rapidly between the nurse's finger, held at a distance of approximately 50 centimetres from the client's face, and the client's own nose. The client should be able to touch their nose in a rhythmic pattern.
• The client should be asked to touch each finger on their hand to their thumb, in rapid sequence; the client should be able to perform this activity using a rhythmic pattern.

Also as described in the above table, it is important that a client's deep tendon reflexes are assessed. This is done as follows:

• To assess the triceps reflex, a nurse should grasp a patient's arm with the elbow flexed at a 90° angle. The triceps tendon - located just above the elbow, at the back of the arm - should be struck with a reflex hammer. The nurse should observe contraction of the triceps tendon with extension of the elbow.
• To assess the biceps reflex, a nurse should grasp a patient's arm with the elbow flexed at a 90° angle. The biceps tendon - located just above the elbow, on the inside of the arm - should be struck with a reflex hammer. The nurse should observe contraction of the biceps tendon with flexion of the elbow.
• To assess the patellar reflex, a nurse should position a patient so they are sitting with their legs hanging freely at a 90° angle. The patellar tendon - located just below the patellar, or kneecap - should be struck with a reflex hammer. The nurse should observe contraction of the patellar tendon with extension of the knee.
• To assess the Achilles tendon, a nurse should position a patient so they are sitting with their legs hanging freely at a 90° angle. The Achilles tendon - located at the back of the ankle - should be struck with a reflex hammer. The nurse should observe contraction of the gastrocnemius muscle with plantar flexion of the foot (i.e. the foot will turn upwards).

The deep tendon reflexes are scored as follows:

Differential diagnosis in the neurologic system

When assessing a patient's neurologic system, there are a number of common problems and conditions a nurse may identify. Consider the conditions and their key clinical findings, outlined in the following table. This information can be useful in assisting a nurse to make a differential diagnosis of a neurologic condition:

Conclusion

As you learned in this chapter, the neurologic system is fundamental in controlling the body's functions, and in enabling responses (both automatic and voluntary) to external and internal stimuli. It is important that nurses are able to accurately and comprehensively assess this system, and this chapter has introduced the fundamental knowledge and skills nurses require to do so. It began with an overview of the fundamental anatomy and physiology of the neurologic system. The chapter then explained the processes involved in collecting a general health history for the neurologic system, and in performing a physical examination of the neurologic system. Finally, this chapter considered a number of special observation and assessment techniques which may be used in the physical examination of the respiratory system, and it discussed performing differential diagnosis relevant to the neurologic system. In completing this chapter, you have equipped yourself with the knowledge and skills necessary to complete a comprehensive assessment of a person's neurological system.

Reference list

Cox, C. (2009). Physical Assessment for Nurses (2nd edn.). West Sussex, UK: Blackwell Publishing, Ltd.

Jensen, S. (2014). Nursing Health Assessment: A Best Practice Approach. London, UK: Wolters Kluwer Publishing.

Wilson, S.F. & Giddens, J.F. (2005). Health Assessment for Nursing Practice (4th edn.). St Louis, MI: Mosby Elsevier.

Example essay

Critically reflect on your own practice to identify and describe a time when you applied critical thinking to the results of a patient assessment to make a differential diagnosis. Your paper should be structured using one of the models of critical reflection.

To develop and improve their professional practice, it is essential that nurses engage in a process of critical reflection (Price & Harrington, 2010). Reflection involves nurses seeking to understand their past practice, with the goal of improving their future practice (Bulman, 2013). For undergraduate nurses in particular, using a reflective model such as the Gibbs Model to structure a critical reflection can contribute significantly to an improvement in practice (Harrison & Fopma-Loy, 2010; Pai, 2015). In this paper, the author will use the Gibbs Model - which involves five phases of structured reflection (Gibbs, 1988) - to reflect on their own undergraduate nursing practice in relation to a time when they applied critical thinking to the results of a patient assessment to make a differential diagnosis.

In the first phase of the Gibbs Model, the nurse describes the event on which they are critically reflecting (Gibbs, 1988). The event on which the author has chosen to critically reflect took place during the author's recent nursing practicum, in the accident and emergency department of a large tertiary hospital. During one evening shift, a forty-five year old woman presented with an acute headache - a disorder which the National Institute for Health and Clinical Excellence (2012: p. 23) describes as one of the most common neurological disorders, but also a "painful and debilitating" one. The woman reported a four-month history of recurrent similar headaches, accompanied by osmophobia, photophobia, aura and nausea. The patient was distressed about her condition, and also because she had not received a diagnosis. She stated to the treating team that she was experiencing "severe pain", that she was "afraid" and that she "need[ed] to know what is going on".

This author recognised the importance of contributing to the patient's differential diagnosis, including through the physical assessment of the patient. There are a number of possible causes for headaches, such as the one the patient on which this critical reflection is based was experiencing. The causes of such headaches include, but are not limited to, migraine, muscle tension, epilepsy, vestibular dysfunction, mild traumatic brain injury, aneurysm and intracranial masses, etc. (Silvia-Neto et al., 2014; Anderson et al., 2015; Cohen & Escasena, 2015; Hartl et al., 2015). The National Institute for Health and Care Excellence's (2012) Headaches in Over-12s: Diagnosis and Management guideline suggests that headaches, regardless of their cause, can be categorised into one of three groups: (1) tension-type headache, (2) migraine (with or without aura), or (3) cluster headache. By undertaking a comprehensive neurological examination of the patient, this author contributed to the process of making a differential diagnosis.

In assessing the patient's neurologic system, this author recorded a number of key pieces of data which contributed to the differential diagnosis. In addition to the symptoms described in an earlier section of this paper, during the physical examination the author identified: (1) her pain to be unilateral (usually focused above one eye and along the corresponding side of the face), (2) her pain to be "throbbing" in nature, and (3) her pain to be very severe, at 10/10 on the pain scale. The patient reported the headaches occurred for upwards of 4 hours with each episode, and the frequency of episodes to be approximately once per week. The patient also reported feeling agitated in the lead-up to a headache, and she stated that the headaches significantly disrupted her capacity to complete normal activities of daily living. This data was documented, and shared with the patient's interdisciplinary health care team to help inform the differential diagnosis.

There are a number of tools which can be used to differentially diagnose a headache; for example, the National Institute for Health and Care Excellence's (2012) Headaches in Over-12s: Diagnosis and Management guideline presents one tool which can be used to differentiate between tension-type headache, migraine (with or without aura) or cluster headache based on the signs and symptoms identified during assessment. According to this tool (National Institute for Health and Care Excellence, 2012), the symptoms experienced by the patient on which this critical reflection is based - including the location, quality, intensity, frequency and duration of the headache-related pain she experienced, the effect of this pain on her capacity to engage in normal activities, the associated symptoms - are characteristic of 'chronic migraine headaches' (National Institute for Health and Care Excellence, 2012). It was this condition with which the patient was diagnosed.

It is important that diagnostic tools - such as the one presented in the National Institute for Health and Care Excellence's (2012) Headaches in Over-12s: Diagnosis and Management guideline, and used in this critical reflection - are used in conjunction with current research evidence about the causes and differential diagnosis of headaches. In this case, the patient's diagnosis of 'chronic migraine headaches' was supported by the research literature reviewed by this author. For example, research suggests that short-lasting visual auras, as experienced by the patient in this case study, are very unlikely to be of epileptic origin and are more likely with migraine headaches (Hartl et al, 2015). Additionally, osmophobia and photophobia, also experienced by the patient in this case study, are seen significantly more often in patients with migraine than any other type of headache (Silvia-Neto et al., 2014).

Once a differential diagnosis was made, treatment commenced. As per the National Institute for Health and Care Excellence's (2012) Headaches in Over-12s: Diagnosis and Management guideline, an oral triptan in combination with paracetamol, plus an anti-emetic, were administered to the patient, with her informed consent. Also consistent with the guideline (National Institute of Health and Care Excellence, 2012), the use of prophylactic propranolol and / or amitriptyline, and other preventive strategies, were discussed with the patient. After these interventions, the patient reported that she "felt much better", was "relieved" and was also "much happier" with the quality of the care she had received.

In the second stage of the Gibbs Model, the nurse reflects on the feelings associated with the event (Gibbs, 1988). In response to this event, the author experienced a number of complex emotions. The author was initially alarmed at the potential seriousness of the patient's condition, and at the fact that she had not received a diagnosis despite suffering from a recurrence of the problem, and presenting repeatedly to the accident and emergency department, on a number of occasions in the previous four months. The author was also confronted by the challenge of contributing to the differential diagnosis of the patient, including undertaking a neurological assessment, as the author recognised the differential diagnosis of headache to be a complicated undertaking (Kim et al., 2016). Finally, at the end of the scenario the author was satisfied that their assessment of the patient contributed to the development of a differential diagnosis, and that this meant the patient's condition could be more effectively managed.

In the third and fourth stages of the Gibbs Model, the nurse evaluates and analyses the event (Gibbs, 1988). It was clear at the beginning of the case study on which this critical reflection is based that differential diagnosis was necessary, but that diagnostic activities had not been undertaken during any of the patient's previous recent presentations to the accident and emergency department. In a subsequent review of the literature, this author found that it is relatively common for patients who present to acute health care settings with headache, including recurrent headache, to not receive a diagnosis, because the causes of headache are varied and complex (Kim et al., 2016). Furthermore, research suggests that migraine - the condition with which the patient in this case study was diagnosed - is particularly difficult to identify, with less than 25% of patients with migraine receiving an accurate diagnosis in their initial presentations to an acute health care setting (Dodick et al., 2016). Minen et al. (2016) find that when clinicians are appropriately educated about the differential diagnosis of headache, as was the case in this scenario, they are more capable of correctly diagnosing and effectively treating headache, including migraine.

In the fifth and sixth stages of the Gibbs Model, the nurse draws conclusions about the event - explaining what else might have been done and what has been learned - and develops and action plan to improve their future practice based on the reflection undertaken (Gibbs, 1988). In critically reflecting on this event, the author has recognised the importance of differential diagnosis, both in: (1) enabling the correct treatment of a patient's condition, and the subsequent relief of their symptoms, and (2) in improving the patient's satisfaction with the care they receive. The author has also recognised the importance of comprehensive patient assessment in contributing to an accurate differential diagnosis. These are key findings the author can apply to improve their future nursing practice.

In this paper, the author used the Gibbs Model to reflect on their own undergraduate nursing practice in relation to a time when they applied critical thinking to the results of a patient assessment to make a differential diagnosis. The author demonstrated how their comprehensive neurological assessment of a patient presenting to an accident and emergency department with an acute headache and associated symptoms contributed to the development of a differential diagnosis for that patient. This differential diagnosis led to the correct treatment of a patient's condition (and the subsequent relief of their symptoms) and an increase in the patient's satisfaction with the care they received. In completing this critical reflection, the author has identified these as important strategies they can use to improve their own future nursing practice.

References

Anderson, K., Tinawi, S., Lamoureux, J., Feyz, M. & de Guise, E. (2015). Detecting migraine in patients with mild traumatic brain injury using three different headache measures. Behavioural Neurology [ePublication].

Bulman, C. (2013) Reflective Practice in Nursing. In C. Bulman & S. Schultz. (eds.). Reflective Practice in Nursing. Oxford: Wiley-Blackwell.

Cohen, J.M. & Ecasena, C.A. (2015). Headache and dizziness: How to differentiate vestibular migraine from other conditions. Current Pain and Headache Reports, 19(7), 31-39.

Dodick, D.W., Loder, E.W., Manack Adams, A. & Buse, D.C. (2016). Assessing barriers to chronic migraine consultation, diagnosis and treatment: Results from the chronic migraine epidemiology and outcomes (CaMEO) study. Headache: The Journal of Head & Face Pain, 56(5), 821-828.

Forrest, M.E.S. (2008). On becoming a critically reflective practitioner. Health Information and Libraries Journal, 25(3), 229-232.

Gibbs, G. (1988). Learning by Doing: A Guide to Teaching Learning Methods. Oxford: Oxford Brookes University.

Harrison, P.A. & Fopma-Loy, J.L. (2010). Reflective journal prompts: A vehicle for stimulating emotional competence in nursing. Journal of Nursing Education, 41(11), 644-652.

Hartl, E., Remi, J. & Noachtar, S. (2015). Two patients with visual aura: Migraine, epilepsy or migralepsy? Headache: The Journal of Head & Face Pain, 55(8), 1148-1151.

Kim, S.K., Moon, H.S., Cha, M.J., Kim, B.S., Kim, BK., Park, J.W., Park, K.Y, Soh, J.H., Chu, M.K., Song, T.J., Kim, J.M. & Cho, S.J. (2016). Prevalence and features of a probable diagnosis in first-visit headache patients based on the criteria of the third beta edition of the international classification of headache disorders: A prospective, cross-sectional multicenter study. Headache: The Journal of Head & Face Pain, 56(2), 267-275.

Minen, M., Shome, A., Halpern, A., Tishler, L., Brennan, K.C., Loder, E., Lipton, R. & Silbersweig, D. (2016). A migraine management training program for primary care providers: An overview of a survey and pilot study findings, lessons learned and considerations for further research. Headache: The Journal of Head & Face Pain, 56(4), 725-735.

National Institute for Health and Clinical Excellence. (2012). Headaches in Over-12s: Diagnosis and Management. Retrieved from: https://www.nice.org.uk/guidance/cg150/resources/headaches-in-over-12s-diagnosis-and-management-35109624582853

Pai, HC. (2015). The effect of a self-reflection and insight program on the nursing competence

of nursing students: A longitudinal study. Journal of Professional Nursing, 31(5), 424-431.

Price, B. & Harrington, A. (2010). Critical Thinking and Writing for Nursing Students. London: Learning Matters.

Scaife, J. (2010). Supervising the reflective practitioner: An essential guide to theory and practice. London: Routledge.

Silva-Neto, R.P., Peres, M.F.P. & Valenca, M.M. (2014). Accuracy of osmophobia in the differential diagnosis between migraine and tension-type headache. Journal of Neurological Sciences, 311(1-2), pp. 118-122.

Timmins, F., Murphy, M., Howe, R., & Dennehy, C. (2013). 'I hate Gibbs' Reflective Cycle 1998' (Facebook© 2009): Registered nurses' experiences of supporting nursing students' reflective practice in the context of student's public commentary. Procedia Social and Behavioural Sciences, 93(1), 1371-1375.