Neuro Assessment PDF

 Chapter 60 Assessment of Neurologic Function   Function of the Nervous System ▪ Controls all motor, sensory, autonomic, cognitive, and behavioral activities. ▪ Communicates with every other system and maintains homeo...

 Chapter 60 Assessment of Neurologic Function   Function of the Nervous System ▪ Controls all motor, sensory, autonomic, cognitive, and behavioral activities. ▪ Communicates with every other system and maintains homeostasis   Structures of the Neurologic System ▪ Central Nervous System ▪ Brain and spinal cord ▪ Peripheral nervous system ▪ Includes cranial and spinal nerves ▪ Autonomic and somatic systems ▪ Basic functional unit—neuron (nerve cells. Some disease processes relate to damage to certain neurons)   Neurotransmitters ▪ (Deficits in neurotransmitters cause disorders) ▪ Communicate messages from one neuron to another or to a specific target tissue. ▪ Neurotransmitters can potentiate-speed up process, terminate-stop process, or modulate- change a specific action or can excite or inhibit a target cell. ▪ Ex. Parkinson's disease occurs when the nerve cells in the brain that make dopamine are slowly destroyed. Without dopamine, the nerve cells in that part of the brain cannot properly send messages. This leads to the loss of muscle function. (dopamine coordinates smooth muscle movement and fine muscle movement. Fine movements are a little bit off. Difficulty with holding utensils, tremors, etc.) ▪ Many neurologic disorders are due to imbalance in neurotransmitters.   3 major areas of the brain ▪ Cerebrum ▪ Brain stem ▪ Cerebellum   ▪ Cerebrum (largest area) Cerebrum ▪ Two hemispheres, thalamus and hypothalamus and basal ganglia ▪ Has four lobes Frontal: Parietal: Concentration, abstract thought, memory, Sensory, proprioception, size/shape motor fx discrimination, left-right orientation Broca’s area motor speech (may have issues (might be able to physically drive car but won’t with speech if damaged. Understand know if left or right foot is on the gas) everything you’re saying and know exactly what they want to say but they can’t get it out), affect, judgment, personality (might not act like themselves if damaged), inhibitions (pt. jumping out of bed, safety concerns, etc) Temporal: Occipital: Auditory receptive, memory of sound, Visual interpretation and memory understanding of language and music (might loose vision in one field, blurry vision= (temporal damages causes pt to have no clue what worried about occipital stroke) they are hearing. EX. Pt. had no clue what they sound was that she was hearing but it was her dog barking)   Cerebrum (continued) ▪ Hypothalamus ▪ Connects to the pituitary gland ▪ Center for autonomic nervous system activities ▪ Regulates pituitary secretion of hormones ▪ Fluid balance, temperature regulation, appetite control, sleep-wake cycle, blood pressure, emotional responses ▪ (worried about temp regulation- warming or cooling blanket- if hypothalamus issues)   Brain Stem ▪ (activities necessary for life in brainstem) ▪ Midbrain ▪ Contains sensory and motor pathways ▪ Center for auditory and visual reflexes ▪ Pons ▪ Contains sensory and motor pathways; assists with regulating respiration ▪ Medulla Oblongata ▪ Reflex centers for respiration, BP, HR, coughing, vomiting, sneezing, swallowing, and the sleep-wake cycle (responsible for reflexes that are protective in nature) ▪ (Brainstem injured pt. might not feeding tube, ventilator, respiratory support, cardiac support, etc. BAD)   Cerebellum ▪ Smooth coordinated movement and balance ▪ Proprioception (also called postural sense) (knowing where body parts are in relation to space) ▪ (often referred to as drunk center. Cerebellum injuries present as if they are intoxicated- stumbling, unsteady gait, speech disorganized, etc.)   Meninges and Related Structures Dura mater – tough mother – outermost tough, leather- like, in-elastic Arachnoid mater – spider mother – middle protective layer, thin, delicate, loosely hugs the brain and spinal cord, avascular Pia mater – tender mother – innermost covers and contours the spinal tissue and brain, vascular CSF circulates around the surface of the brain and spinal cord   Meninges ▪ Dura mater – tough mother – outermost tough, leather-like, in-elastic ▪ Epidural space (on top) and subdural space (towards bottom) (areas of brain that may collect blood or infection) ▪ Arachnoid mater – spider mother – middle protective layer, thin, delicate, loosely hugs the brain and spinal cord, avascular-no vessels running through ▪ Pia mater – tender mother – innermost covers and contours the spinal tissue and brain, vascular ▪ CSF circulates around the surface of the brain and spinal cord (meningitis- looks at entire meninges that hug spinal cord and brain. Can have problems anywhere in that covering) ▪ Immune and metabolic functions of brain (if CSF gets too high, we see increased cranial pressure that could compromise the brain)   Arterial Blood Supply of the Brain -Vessels are really delicate -No valves in the brain. BP needs to be strong enough and you need enough blood volume to pump blood to brain. Need BP and HR to be good to oxygenate and get blood to brain –Brain and cardiac are dependent on each other. Symbiotic relationship   Brain blood flow ▪ Up through the common carotid arteries from the aorta, down through the IJ vein back to the heart ▪ No valves – rely on BP and gravity ▪ 750ml of blood per min (15% of cardiac output) ▪ Circle of Willis collateral circulation allows blood flow to be redirected as needed (How brain protects itself if it ever gets blocked off from blood from clot or disease. Might only lose function of small piece) ▪ Cerebral circulation allows redirection of blood flow ▪ decreases with aging ▪ Double layered, not triple ▪ Weakened, ruptures ▪ The circle of Willis is formed when the internal carotid artery (ICA) enters the cranial cavity bilaterally and divides into the anterior cerebral artery (ACA) and middle cerebral artery (MCA). The anterior cerebral arteries are then united by an anterior communicating (ACOM) artery. These connections form the anterior half (anterior circulation) of the circle of Willis. Posteriorly, the basilar artery, formed by the left and right vertebral arteries, branches into a left and right posterior cerebral artery (PCA), forming the posterior circulation. The PCAs complete the circle of Willis by joining the internal carotid system anteriorly via the posterior communicating (PCOM) arteries   Blood - Brain Barrier ▪ The CNS is inaccessable to many substances that circulate in the blood plasma ▪ Formed by endothelial cells of the brain’s capillaries ▪ (Blood brain barrier is good at keeping things out. However, if there is a meningitis, it is hard to get medications in)   Peripheral Nervous System ▪ Spinal Nervous: 31 pair ▪ Cranial Nerves: 12 pair ▪ Autonomic Nervous System   Spinal Nerves ▪ Each spinal nerve has a ventral and dorsal root ▪ Dorsal: transmit sensory information along dermatomes-specific places within spinal network that stop at midline (shingles- lesions break out along roots of nerves. Itchy, painful and stop at midline. Lesions stop and wont cross and go the whole way over. It stops midline) ▪ Ventral: motor   Dermatome Distribution/Spinal Nerves Pg. 1973 Don’t need to memorize   Cranial Nerves pg 1972 ▪ 1 (olfactory- smell) ▪ 2 (optic- visual acuity. Snellen chart) ▪ 3 (occular motor- pupillary response) ▪ 4 (trochlear- eye movement looking up and down) ▪ 5 (trigeminal- sensation of face. Touch forehead, cheek, and jaw) ▪ 6 (abducens- eye movement side to side) ▪ 7 (facial- check smile, symmetry) ▪ 8 (acoustic- vestibular- controls hearing. Dizziness, vertigo, tinnitus) ▪ 9 (glossopharyngeal- tongue- TASTE, swallow, gag reflex) ▪ 10 (vagus- swallowing and gag reflex) ▪ 11 (spinal accessory- shrug shoulders) ▪ 12 (hypoglossal- stick out tongue- motor response)   Autonomic Nervous System ▪ Functions to regulates activities of internal organs and to maintain and restore internal homeostasis ▪ Regulates activities in heart, lungs, digestive organ, blood vessels ▪ Sympathetic NS “Fight or flight” responses *next slide ▪ Main neurotransmitter is norepinephrine…releases epinephrine ▪ Parasympathetic NS (visceral function -everything slows) ▪ Controls mostly visceral functions ▪ Main neurotransmitter is acetylcholine ▪ Regulated by centers in the spinal cord, brainstem, and hypothalamus ▪ (any injury in brainstem can cause deficit in both of systems)   Fight or Flight ▪ Bronchioles dilate (More oxygen in to send to muscles) ▪ Heart beats stronger and faster (Pushing more blood to core organs) ▪ Arteries dilate ▪ Peripheral vessels constrict (Might feel cool hands and feet. Shuffling blood to heart, brain, muscles, etc.) ▪ Pupils dilate ▪ Liver releases glucose   Neurological Assessment ▪ History of present illness ▪ Alert and oriented (do you know who you are, why you are here, etc) ▪ Stable or progressive? (Slow decline over time or did it just start? Sudden, stable, or progressive) ▪ May have symptom free period or symptoms fluctuate ▪ Impact on lifestyle (may have sensory deficits, weakness in extremities that impairs driving, walking, ADLs, etc) ▪ Past health, family and social history (do they have access to resources they might need?) ▪ Seizures-fever? Drug/alcohol? (even just meds in general) Hypoglycemia? (electrolyte imbalances) Brain Lesions? ▪ Presence of pain-acute or chronic? ▪ Abnormal sensations (Numbess, tingling, pins and needles, where located, does anything change it), Weakness, Dizziness or Vertigo (common in elderly) (dizziness is abnormal sensation of being off balance with movement. Vertigo is illusion that everything is moving around you in rotation) ▪ Dizziness: abnormal sensation of imbalance or movement ▪ Vertigo: illusion no movement, usually rotation   Neurologic Physical Assessment ▪ Consciousness and Cognition; further broken down into: ▪ mental status ▪ Behavior, dress, grooming* (often something family notices over period of time), orientation ▪ intellectual function ▪ Proverbs, counting backward by 7’s (hold out two objects and ask how they are similar, What does dog and cat have in common, etc) ▪ thought content - spontaneous? Clear and relevant? Answers questions appropriately? Hallucinations? ▪ emotional status – irritable? Flat? (are emotions appropriate to situation? Laughing during difficult time, etc) ▪ language ability – aphasia (is speech clear, coherent, speaking with comprehendible pathway and not jumbling things together) ▪ LOC –pinch? (alert and responding, responsive to verbal cues, sternal rub, pinch test, etc) *Note the impact of any neurologic impairment on lifestyle and patient abilities and limitations ▪   Assessment of the Nervous System (cont) ▪ Cranial nerves (later) Nice assess. review on P 1972 ▪ Motor system; posture (can they sit upright unsupported), gait, muscle tone and strength, coordination and balance, Romberg test (always comparing left to the right side) ▪ Sensory system; tactile sensation (can they feel you touching them), superficial pain, vibration and position sense ▪ Reflexes* ▪ DTRs (patellar reflex- often don’t assess in hospital) ▪ plantar (Babinski) abnormal after age 2 (toes fan out and flare. Normal for newborn but should disappear after 2. Head injury might cause this reflex to pop back up) ▪ Are they able to blink, swallow, cough, etc? ▪ Babinski's reflex occurs when the big toe moves toward the top surface of the foot and the other toes fan out after the sole of the foot has been firmly stroked. This reflex, or sign, is normal in very young children. It is not normal after age 2.   Gerontological Considerations ▪ Important to distinguish normal aging changes from abnormal changes ▪ Determine previous mental status for comparison (talk to family, etc). Assess mental status carefully to distinguish delirium from dementia (delirium has pathological cause- new environment, low BS, lack of oxygen, infection, etc.; dementia is progressive and not reversible) ▪ Normal changes may include: ▪ Losses in strength and agility; changes in gait, posture and balance (stance different with age as muscles decrease); slowed reaction times and decreased reflexes; visual and hearing alterations; deceased sense of taste and smell; dulling of tactile sensations; changes in the perception of pain; and decreased thermoregulatory ability   Diagnostic Tests ▪ Computed tomography(CT) ▪ Positron emission tomography (PET) ▪ Magnetic resonance imaging (MRI) ▪ Cerebral angiography ▪ Noninvasive carotid flow studies ▪ Electroencephalography (EEG) ▪ Lumbar puncture ▪ (do labs, CBC, differential, look for infection, etc)   CT ▪ Cross sectional (use radiation to produce image- really quick to do- between 5-15 min. Good in emergent situation) ▪ X ray beams “slice through you like a spiral ham” ▪ Quick, painless, small amount radiation ▪ With or without contrast – shellfish? (really hard on kidneys- watch BUN and CR to make sure kidneys can tolerate; may be hydrated before or after contrast to flush it out; watch for allergies to shellfish or iodine; contrast be oral or iv. If hives, they might premedicate with Benadryl. If respiratory rxn, they won’t order contrast) ▪ Hold head perfectly still – what if they can’t? (if they don’t hold still, we might medicate with a little sedation) ▪ Renal function ▪ IV access (need to have this)   CT CT brain Scanner   MRI ▪ (More clear image than a CT scan) ▪ Magnet→ signals→ images ▪ With or without contrast (same rules apply for contrast) ▪ Can find abnormality earlier and more clearly than other tests ▪ 1 hr, not for emergencies (take a long time. Wouldn’t do this if worried about brain bleed, etc) ▪ Metal objects (pacemakers, med patches, jewelry) (can’t have implants, occupational things like welder having metal in places of body, etc) (Pulls metal pieces out. Heating up from inside out) (titanium joint replacements are fine because they are not magnetic) ▪ Malfunction (esp if pacemaker or internal AED), dislodge or heat up ▪ Equipment IV poles, stethoscopes (don’t take anything metal into the room. Have to room any IV meds from pole and put it in IV poles implanted into the ground. They also have oxygen in the room that is stationary) ▪ Painless, loud thumping (often give earphones), claustrophobia →sedation  Magnetic Resonance Imaging   ▪ Computer based nuclear imaging of actual organ function (shows organ working in real time) PET ▪ Radioactive gas inhaled, or radioactive tracer/glucose is injected IV ▪ Two dimensional views are meshed by a computer, giving a composite picture of the brain at work ▪ Measures brain metabolism (“eating” the glucose) ▪ Tumors (they gobble up glucose really quickly), blood flow issues, metabolic changes (Alzheimer’s, Parkinsons, neurotransmitter issues) ▪ 30 min to 2 hours ▪ PET and PET/CT scans are performed to: ▪ detect cancer. ▪ determine whether a cancer has spread in the body. ▪ assess the effectiveness of a treatment plan, such as cancer therapy. ▪ determine if a cancer has returned after treatment. ▪ determine blood flow to the heart muscle. ▪ determine the effects of a heart attack, or myocardial infarction, on areas of the heart. ▪ identify areas of the heart muscle that would benefit from a procedure such as angioplasty or coronary artery bypass surgery (in combination with a myocardial perfusion scan). ▪ evaluate brain abnormalities, such as tumors, memory disorders and seizures and other central nervous system disorders. ▪ to map normal human brain and heart function.   PET brain Red is area of glucose metabolism   Cerebral Angiography ▪ Invasive test ▪ X ray study of cerebral circulation ▪ Shaved groin, femoral artery, catheter with contrast, we then take pictures (Looks for blockages, masses, blood flow issues, etc. Usually, other stuff is done first. This is a later test) ▪ Check BUN/Creatinine before ▪ Assess puncture site for hematoma (No bleeding, swelling, hematoma) ▪ Neuro assessment during and after (alert/oriented, speech clear, looking at extremity involved, pulses, temp, sensation, movement, weakness, etc. Concern that piece of clot where it is starting to heal breaks off and goes somewhere else) ▪ Altered LOC, unilateral weakness, motor sensory or speech deficits ▪ embolism   Carotid Doppler ▪ Ultrasound ▪ Detects arterial flow, stenosis, or occlusion   EEG ▪ Record of electrical activity (bunch of electrodes glued on scalp) ▪ Seizures, coma (pt who has been unresponsive for days, we can look for brain activity) ▪ 45 min or 12 hour (can be done over days) ▪ Hold sedatives, seizure meds 24 to 48 hrs prior to study, may mask seizure activity on EEG (might wean pt off meds. We want them to seize so we can see what part of the brain the abnormal activity is happening. If not super important, they might just take that area of the brain out) ▪ If assessing for seizure activity, withhold sleep night before eval ▪ Do not withhold meal, because altered blood glucose levels change brain wave patterns, but avoid stimulants like caffeine  EEG   LP ▪ Also invasive ▪ “Spinal Tap” (remove CSF and send it to get analyzed) ▪ CSF examination, reduce CSF pressure (can treat hydrocephalus which increases intracranial pressure) ▪ Needle into the Subarachnoid space between third and fourth or fourth and fifth lumbar vertebrae (low in back) ▪ Position patient to “stretch” the canal (cannonball position. Might have them lean over bedside table if able or curl into a ball while on their side) ▪ CSF should be clear, odorless, colorless ▪ Pink/bloody indicates SAH (subarachnoid hemorrhage) ▪ Headache, throbbing, hours to days, blood patch (worried about bleeding and infection. Monitor vitals, labs, spinal headache- CSF leaks out of puncture site- feel fine laying flat on back but when sitting up, they immediately get a headache. Will increase fluids, give caffeine, or give blood patch- withdraw blood from arm and inject into site to close it off) ▪ Page 1990 ▪ Inserting a needle into the lumbar subarachnoid space (between the 3rd and 4th or 4th and 5th lumbar vertebrate.) the spinal cord ends at the first lumbar vertebrate…..we insert below that level to avoid puncture. ▪ Used to withdraw CSF….used to decrease pressure, CSF examination...also looks for the presense or absense of blood in the csF,,,can also be used to administer medication intrathecally (into the spinal canal) ▪ Normal CSF is 8-14