Neuro Flashcards
Of the ABCs, how can “breathing” be related to AMS?
- Lack of O2 -> resp acidosis -> AMS
- Resp depression -> consider narcotic OD
What is the D and E from ABCDE?
D = disability, neurologic (e.g. do GCS) E = expose (do head -> toe exam)
At a minimum, all AMS patients deserve (initially):
- Assessment of the ABC’s
- Cardiac monitoring and pulse oximetry
- Supplemental oxygen if hyperemic
- Bedside glucose testing
- Intravenous access
- Evaluation for signs of trauma and consider c-spine stabilization
- Consider naloxone administration if narcotic overdose is suspected
What are 2 easily and quickly reversible causes of AMS?
Hypoglycemia
Narcotic OD
*What’s the mnemonic for AMS ddx?
AEIOU TIPS
A Alcohol E Epilepsy, Electrolytes, Encephalopathy I Insulin O Opiates and Oxygen U Uremia
T Trauma and Temperature
I Infection
P Poisons and Psychogenic
S Shock, Stroke, SAH, Space-Occupying Lesion
Which of the following often have abnormal vital signs?
Delirium
Dementia
Psychosis
Delirium
Describe the hallucinations seen in the following:
Delirium
Dementia
Psychosis
Delirium: visual (external stimuli)
Dementia: rare
Psychosis: auditory (internal stimuli)
Although typically managed by PCPs, why are dementia pts sometimes seen by ED physicians?
Admission for safety, social assessment and placement.
- Psychosis managed by psychiatry
Normal consciousness requires both _______ and ________.
arousal and cognition
Delirium is brain dysfunction resulting in alterations of both level of arousal and ______________.
thought content
Many medical conditions manifest as AMS when decompensated. For example:
- diabetes (DKA, HHNK),
- HTN (hypertensive encephalopathy or medication OD)
- endocrine disease (thyroid, Addison)
- renal failure
- cancer (paraneoplastic syndromes, Na+, Ca++)
- dementia
- cardiovascular and cerebrovascular disease
- seizure (atypical?)
- psychiatric issues
Recall the 3 categories of GCS and their point values.
Eyes (4
Verbal (5)
Motor (6)
List the point value of “eyes” in the GCS.
4 - Spontaneous
3 - Loud voice
2 - To Pain
1 - None
List the point value of “verbal” in the GCS.
5 – Oriented 4 – Confused 3 – Inappropriate words 2 – Incomprehensible sounds 1 – No Sounds
List the point value of “motor” in the GCS.
6 – Obeys 5 – Localizes to pain 4 – Withdraws to pain 3 – Abnormal flexion posturing 2 – Abnormal extension posturing 1 – None
Why was GCS designed?
How is it useful in intubation?
to predict outcome after head trauma
“less that eight, intubate!”
What should you do before a pt w/AMS tries to sign out AMA?
Document decision-making capacity
Describe the classic onset of a subarachnoid hemorrhage (SAH).
acute onset “thunderclap” headache that may be accompanied by loss of consciousness, vomiting, neck stiffness, or seizure.
- Occipital in location, often
- Sometimes warning (sentinal) headache
Review this Hunt and Hess Grading System for SAH.
- Asymptomatic, mild headache, slight nuchal rigidity 1
- Moderate to severe headache, nuchal rigidity , no neurologic deficit other than cranial nerve palsy 2
- Drowsiness / confusion, mild focal neurologic deficit 3
- Stupor, moderate-severe hemiparesis 4
- Coma, decerebrate posturing 5
What are some r/f’s for SAH and intracerebral bleeds?
*Which is the #1 r/f for SAH?
Recent exertion, hypertension, excessive alcohol consumption, sympathomimetic use, and cigarette smoking
The strongest risk factor for SAH is family history, which carries a 3 – 5 fold risk.
Most SAH is due to the rupture of _________________.
saccular aneurysms
- It is important to note that most aneurysms do not rupture.
Describe the classic presentation of epidural hematoma (EDH).
Brief loss of consciousness after a blow to the head, followed by a lucid period.
- Soon after, level of consciousness deteriorates again, possibly progressing into herniation and death.
- ‘talk and die’ phenomenon.
Which type of head bleed is a/w rupture of the middle meningeal artery?
Epidural hematoma
Subdural hematomas are extra axial blood collections between the dura and the arachnoid mater. Subdural hematomas form from this pathophysiological mechanism.
Bridging veins are sheared during acceleration-deceleration of the head.
In the pediatric population, presence of acute or chronic SDH should raise suspicion of for _____________.
child abuse
- Also from birth trauma
What are some major signs of “shaken baby syndrome”?
- subdural hematoma
- retinal hemorrhages
- long bone fractures
- bulging fontanelle
- enlarged head circumference
- emesis
- FTT
- seizure
Which of the brain bleeds is known as the “great imitator”?
CHRONIC subdural hematoma
- Most often p/w AMS
What is the preferred method of controlling the airway in brain bleeds?
A neuroprotective rapid-sequence intubation protocol
- Check fingerstick glucose first
In brain bleeds, neurosurgeons often find the documentation of a pre-intubation _____________________ to be helpful in determining prognosis.
neurological exam
*What documentation should you include in your pre-intubation neuro exam of the brain bleed pt?
At minimum, such an assessment should include documentation of the GCS, the pupillary size and reactivity, and motor strength in the four limbs.
- Sensation and reflexes can be included if time permits.
- Cushing’s triad describes the physiologic response to ____________________________________.
- Its features are: (3)
rapidly increasing ICP and imminent brain herniation
- Hypertension
- Bradycardia
- Abnormal respiratory patterns
_____________ is the mainstay of diagnosis in ICH.
Head CT
*Describe how blood appears at the acute, subacute, and after 2 week time points during an intracranial hemorrhage. (3)
- Acute bleeding appears hyperdense (whiter)
- The subacute phase occurs between days 3 and 14, when blood becomes isodense to the brain parenchyma (most difficult time to spot bleed)
- After ~ 2 weeks, blood appears hypodense (darker)
In blood is seen on LP, what are the 3 possible scenarios to cause this?
SAH, infection, or a traumatic tap
How can you tell if the blood on an LP is due to a “traumatic tap”?
If the # of RBCs decreases by 50% from tube 1 to tube 4.
- This can occur in SAH as well, so the tap should only be labeled ‘traumatic‘ if the fourth tube is almost completely free of blood (less than 5 rbc’s per high powered field).
What is “xanthochromia” on LP, and what does it result from?
A yellow or pink discoloration of the supernatant once the CSF is centrifuged. It results from the breakdown of blood cells within the CSF
*What dx does the presence of xanthochromia point to?
The presence of xanthochromia is highly sensitive for SAH.
*If the initial CT or LP is c/w SAH, what is the next diagnostic step?
Some form of angiography is necessary.
- Digital subtraction angiography (DSA) is the gold standard
- Since CT angiography is rapid and non-invasive, it is commonly used
What do you need to do/consider (labs, tests, tx’s) for all pts with brain bleed? (review)
- Assess and reassess the ABCD’s
- Discontinue or reverse anticoagulation
- Prevent hypotension and hypoxemia
- Control ICP
- Prevent seizure: prophylaxis may be necessary
- Treat fever and infection aggressively
- Control blood glucose (target 140-185 mg/dL)
- How can you manage ICP in a brain bleed:
- Should you raise or flatten the head of bed?
- Does sedation/analgesia help or hurt?
- *If rapidly rising ICP, what’s a med and a tx you could consider?
- Monitoring/lowering BP in consultation with neurosurgery
- Elevating the head of the bead to 30 degrees
- Providing adequate sedation and analgesia
- If signs of rapidly rising ICP or herniation, considering mannitol or mild hyperventilation (target CO2 around 30 mmHg)
If your patient consents to an LP, be sure to warn them of the risk of ___________________ (frequency ranges 10-20%) and other complications
post-LP headache
Review the ddx of ischemic stroke.
Structural brain lesion (tumor, AVM, aneurysm, hemorrhage)
Infection (cerebral abscess, septic emboli)
Seizure Disorder and post-seizure neurologic deficit (Todd’s paralysis)
Peripheral Neuropathy (Bell’s palsy)
Complicated Migraine
Hypoglycemia
Conversion Disorder
Toxins
Hypertensive encephalopathy
Demyelinating dz
In strokes, the single most important component of the history is _________________.
“last known well” time
List some stroke r/f’s.
- hypertension,
- diabetes,
- hyperlipidemia,
- tobacco abuse,
- advanced age,
- a-fib,
- prosthetic heart valve,
- prior stroke
In patients receiving thrombolytic therapy, the most common stroke mimics include: (3)
- complicated migraine,
- seizure
- conversion disorde