Assessment of the Nervous System Chapter 43 Assessment of the Nervous System Mrs. Marion Kreisel MSN, RN Nu230 Adult Health 2 Fall 2011

Anatomy and Physiology Neurons: The basic unit of the NS, the neuron transmits impulses. Mechanism for nerve impulse conduction: Motor neurons for movement and sensory neurons for sensation Neuroglial cells: provide protection , structure & nutrion for the neurons ANS, sympathetic and parasympathetic

Anatomy and Physiology (Cont.)

Assessment Family history and genetic risk Current health problems Level of consciousness and orientation Memory and attention Language and higher levels of cognition

Assessment (Cont’d) Cranial nerves: KNOW CHART 43-4 on PAGE 935 Sensory function Motor function Cerebellar function

Assessment (Cont’d) Reflex activity

Glasgow Coma Scale A score of 15 is normal neurological functioning. A score of 7 represents a comatose state. The lower the score the lower the patients LOC Intubated patients and cannot talk get a “T” after the number. The highest they can score is an 11

Posturing DECORTICATE DECEREBRATE

Laboratory Tests Blood cultures necessary Skull and spine x-ray tests Cerebral angiography CT scan—possible use of contrast medium, assess for allergic response, fluids MRI Positron emission tomography Single-photon emission CT Magnetoencephalography (MEG)

Electroencephalography (EEG) Graphically records the electrical activity of the cerebral hemispheres Sleep deprivation requirement Anticonvulsants possibly withheld

Evoked Potentials Measure the electrical signals to the brain generated by hearing, touch, or sight Auditory evoked potentials: assess high frequency hearing loss, damage to the acoustic nerve. Sound proof room, one ear at a time. Visual evoked potentials: detect loss of vision from optic nerve damage particularly in MS. On eye at a time and focus on a shifting checker board pattern Somatosensory evoked potentials: measure response from stimuli to the peripheral nerves. Detects nerve or spinal cord damage/degeneration esp. in MS. Tiny shocks to arm & leg

Cerebral Blood Flow Evaluation Particularly useful in evaluating cerebral vasospasms Use radioactive substances measure the uptake of it in an area.

Lumbar Puncture (Spinal Tap) Insertion of spinal needle into the subarachnoid space (between the third and fourth lumbar vertebrae) CSF pressure readings Check for blockage by SC lesion Inject contrast for test Inject medications Rarely used to reduce some ICP Contraindicated in patients with increased intracranial pressure b/c sudden release of SF Empty bladder Position Spinal headache possible from spinal tap

Lumbar Puncture (Spinal Tap) continued Normal Pressure <20 mm H20 Normal Color: Clear Normal Cells: 0-5 lymphocytes more than that means infection! Normal Protein: 15-45 mg/dl. High means infection! Normal Glucose: 50-75mg/dl KNOW THIS SLIDE!

Cerebrospinal Fluid

Other Studies Transcranial Doppler ultrasonography: Uses sound waves to measure blood flow through the arteries. Muscle and nerve biopsy: used to DX neuromuscular disorders.

NCLEX TIME

Question 1 The nurse can best assess the patient’s cognition by: Asking the patient about how he was transported to the clinic Asking the patient about the meaning of various proverbs Asking the patient to count backward from 100 by 7s Writing down a simple command and giving it to the patient Answer: B Rationale: Asking the patient about the meaning of various proverbs would assess the patient’s abstract reasoning, which is part of cognition. Asking the patient about how he came to the clinic would assess memory. Counting backward from 100 by 7s would assess the patient’s attention. Giving the patient a simple written command would assess language and copying skills.

Question 2 The most common cause responsible for changes in an older patient’s mental state is: Changes in extracellular electrolytes Insufficient oxygen Sedative agents Changes in acetylcholine levels Answer: B Rationale: Many things influence transmission of nerve impulses affecting mental state. In the older adult, a lack of oxygen often causes mental status changes. Changes in extracellular electrolytes, specifically sodium, can also alter mental status, as can hypnotic, anesthetic, and sedating agents. Acetylcholine will also influence effectiveness of neuronal function.

Question 3 Approximately how much cerebrospinal fluid (CSF) is produced daily by the choroid plexus? <100 ml 125 ml to 150 ml 200 ml to 300 ml 500 ml Answer: D Rationale: Approximately 125 to 150 ml of cerebrospinal fluid is constantly circulating in the ventricles and subarachnoid space and reabsorbed. Approximately 500 ml of cerebrospinal fluid is produced daily by the choroid plexus.

Question 4 The nurse provided colostomy care instruction to an older adult yesterday. Today, the nurse observes that the patient is not applying the colostomy collection device correctly. The nurse should: Request the patient’s daughter learn how to care for the patient’s colostomy. Re-instruct the patient on the care of the colostomy. Offer to complete the colostomy care for the patient. Ask the patient what he remembers about the colostomy care instruction he received the day prior. Answer: B Rationale: Intellect does not decline as a result of aging. However, subtle memory changes such as difficulties with short-term recall are typical with many older adults. When providing new information to an older adult, he or she may need more time or more repetition to process the new information. Thus offering to re-instruct the patient on the care of the colostomy may be needed for the older adult. Completing the colostomy care may be helpful, as may be offering instruction to the patient’s daughter. Asking the patient what he remembers will also give the nurse information about the patient’s short-term memory or retention of new information.

Question 5 Which assessment variable is the best indicator of a change in a patient’s neurologic status? Alert and oriented to place, person, time Alert but not oriented to place, person, or time Lethargic but arousable Deep stimulation needed to arouse patient Answer: B Rationale: A change in level of consciousness (LOC) is the first indication that central neurologic function has declined. A patient may be alert but not oriented to person, place, or time. Patients who are less than alert are labeled lethargic, stuporous, or comatose. A lethargic patient is drowsy or sleepy but is easily awakened. One who is arousable only with vigorous or painful stimulation is stuporous. The comatose patient is unconscious and cannot be aroused.