Term
| what is a difference between the comatose evaluation and general neurologic exam? (*know this*) |
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Definition
| the sensory, motor, and reflex evaluations are grouped separately in the neurologic exam, but are grouped together in the comatose exam. |
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Term
| what are the top 3 most important tests in the evaluation of a comatose pt? (*know this*) |
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Definition
| LOC, **eye exam (pupils, EOM, fundi, corneal reflex), and motor/sensory/reflex |
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Term
| what is delirium? (*know this*) |
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Definition
| a condition characterized by disorientation, fear, irritability, and misperception of sensory stimuli w/associated visual hallucinations |
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Term
| what is the "state of consciousness"? (*know this*) |
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Definition
| a statement of the pt's actual behavioral response, usually determined by the glasgow coma scale - based on eye opening, verbal and motor responses. the lowest state is 3 and the highest is 15 (eyes 4, mouth 5, body 6 ). |
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Term
| what is the simple pathway when considering locations in neuro pathology? |
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Definition
| cerebral hemis, midbrain, pons, medulla, spinal cord, nerve roots, peripheral nerves, neuromuscular junction and muscle |
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Term
| what is the difference between the glasgow coma scale and comatose evaluation? (*know this*) |
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Definition
| glasgow coma scale really just evaluates the level of consciousness |
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Term
| what is the difference between coma and locked in syndrome? |
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Definition
| in locked in syndrome the lesion is in the ventral pons and the pt is awake/alert - they just can't move extremities or face. |
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Term
| what is cheyne-stokes breathing? (*know this*) |
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Definition
| crescendo, decrescendo and apnea in breathing pattern = diffuse bilateral hemisphere dysfunction (non-localized). can be related to drug OD or just "normal" during sleep for some pts. |
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Term
| what is biot's breathing? (*know this*) |
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Definition
| irregularly irregular breathing (like a-fib) due to a lesion in the medulla (terminal breathing). |
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Term
| what characterizes BP in a comatose pt? |
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Definition
increasing ICP will result in an elevation the systolic blood pressure, and a widening of the pulse pressure.
an increasing ICP will result in a slowing of the pulse (bradycardia) initially, and if there is a tachycardia in the presence of an increased ICP without hypovolemia, this usually is grave prognostic sign. |
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Term
| what characterizes respiration in a comatose pt? |
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Definition
| an increasing ICP will initially slow the respiratory rate, however, with severe increase in ICP, the patient may demonstrate a tachypnea. |
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Term
| what is the path of the sympathetics running to the pupillary constrictors? |
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Definition
| this sympathetic system begins in the hypothalamus, travels through the brainstem to the lower cervical spine cord region, (first order neuron), and then leaves the CNS. it then will traverse over the apex of the lung, under the subclavian artery, and eventually arrive at the superior cervical ganglion (second order neuron). the third order neuron will then accompany the carotid systems (both internal and external) to its final destinations (CN3 -> pupillary constrictors). if these sympathetics are impaired, the pupils are smaller (miosis), but still reactive to light. |
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Term
| what is horner's syndrome? (*know this*) |
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Definition
| miosis, ptosis, anhydrosis (little eye, little pupil, little sweat) |
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Term
| what is lateral medullary syndrome? |
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Definition
| aka wallenberg's - ataxia due to cerebellar dysfunction: 4 D's (dysphagia, dysarthria, diplopia, and dizziness) |
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Term
| what is a pancoast tumor? |
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Definition
| a tumor of lung pushing on to sympathetics, giving a horner’s syndrome on that side (outside CNS). also possible w/direct trauma to the internal carotid. |
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Term
| what is the path of the parasympathetics running to the pupillary dilators? |
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Definition
| afferent and efferent nerves enter CN2, and the efferent portion with CN3. there is a crossover of the afferent system, both at the optic chiasm and in the tectum of the mid-brain. |
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Term
| what does fixed pupils imply? |
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Definition
| knocked out parasympathetics and sympathetics |
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Term
| w/H-test, what does 1 eye not going medially when the other eye is going laterally imply? |
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Definition
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Term
| what does a CN3 injury tell you? |
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Definition
| likely an issue w/the midbrain (likely MS) |
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Term
| what does a CN6 injury tell you? |
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Definition
| likely an issue w/the pons (likely MS) |
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Term
| what does an issue w/the vestibular nucleus tell you? |
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Definition
| likely an issue w/the medulla (likely MS) |
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Term
| what is next if the pt has a negative doll's eye reflex (oculocephalic reflex: CN3+6)? |
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Definition
| oculovestibular reflex - not caloric test (COWS) if pt is in a coma - but the pt's eyes should look toward the ear you put cold water in (CN6). if the eye stays there = CN3 involvement. |
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Term
| what are you looking for in a funduscopic exam? |
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Definition
| optic disk swelling, hemorrhage (flamed shaped: in retinal layer [DM] or subhyloid: between retinal and vitreous later [SAH]), exudates (cotton woll = severe disease), which can reflect HTN and diabetes |
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Term
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Definition
| CN5: sensory, CN7: lid shutting. bell's phenomenon - eye rolling back to protect itself. |
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Term
| what characterizes motor/sensory/reflex examination in comatose pts? |
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Definition
| appropriate response is pulling away from noxious stimulation - but inappropriate: absent (acute injury), decorticate (flexion/abduction = above red nucleus), or decerebrate (jaw clenched/neck retracted/arm+leg extension+internal rotation = below red nucleus) |
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Term
| what are the major categories of pathology leading to a comatose state? |
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Definition
| content (cerebral) or state of arousal (brainstem). pathology here is usually either supratentorial, subtentorial or metabolic [**most common**] (also possibly psychological). |
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Term
| what characterizes supratentorial mass lesions? (*know this*) |
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Definition
| those which secondarily encroach upon deep diencephalic structures so as to compress or damage the physiological ascending reticular activating system. this includes SDH, ICH (aneurysm or amyloid angiopathy) = **4 types of herniation: cingulate gyrus (herniates under falx), uncal (herniating over falx), central (herniates straight down) or tonsillar (herniates through foramen magnum). (also transcalvarial – if pt has skull fracture or skull removed to give brain space and it’s swelling outside). |
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Term
| what characterizes subtentorial mass or destructive lesions? |
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Definition
| direct damage to brainstem central core |
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Term
| what characterizes metabolic disorders? |
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Definition
| those which widely depress or interrupt brain function |
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Term
| what is a duret's hemorrhage? |
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Definition
| hemorrhage in the brainstem due to herniation of the brain |
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Term
| what is kernahan's notch? |
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Definition
| start out with right hemisphere lesion that gives left side weakness, left side hyperreflexia, left extensor toe response - as uncus herniates over, get dilated pupil on right, 3rd nerve palsy on right - as the brainstem gets pushed over the left side gets injured on the tent because it can’t move (started out with right hemisphere lesion, left side symptoms, but when the notch forms, develop right side symptoms). |
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Term
| what is the one big subtentorial lesion? |
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Definition
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Term
| what are the metabolic etiologies leading to coma? |
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Definition
| hypoxia, sepsis, exogenous toxins, and endogenous toxins |
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Term
| what is the most important thing in tx of coma pts? (*know this*) |
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Definition
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