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
Sx of an ACA stroke?
LE > UE
Sx of an MCA stroke?
UE > LE
Face
aphasia (if dominant hemisphere) or neglect (if non-dominant hemisphere)
Sx of a PCA stroke?
Vision affected
Sx of a vertebrobasilar stroke?
Usually motor/sensory sx + CN sx.
D’s: diplopia, dysarthria, dysphagia, droopy face, dysequilibrium, dysmetria, and decreased level of consciousness
- N/V common here
What are lacunar infarcts?
Small strokes (measuring less than 1.5 cm) caused by occlusion of one of the deep perforating arteries which supplies the subcortical structures and brainstem.
Sx of a lacunar stroke?
the vast majority of lacunar strokes are described by the 5 most common lacunar syndromes:
- pure motor hemiparesis,
- sensorimotor stroke,
- ataxic hemiparesis,
- pure sensory stroke,
- dysarthria-clumsy hand syndrome.
Guidelines for Initial Evaluation and Treatment of Acute Stroke in the Emergency Department:
Door to physician: ___ minutes
Door to stroke team: ___ minutes
Door to lab work completed: ___ minutes (CBC, BMP, PT/PTT, UA, EKG, CXR)
Door to non-contrast CT-head ordered: ___ minutes
Door to CT interpretation: ___ minutes
Door to decision to give tPA: ___ minutes
Door to drug administration: ___ minutes (and less than 3 hours from onset)
Door to admission: ___ minutes
Door to physician: 10 minutes
Door to stroke team: 15 minutes
Door to lab work completed: 45 minutes (CBC, BMP, PT/PTT, UA, EKG, CXR)
Door to non-contrast CT-head ordered: 25 minutes
Door to CT interpretation: 45 minutes
Door to decision to give tPA: 45 minutes
Door to drug administration: 60 minutes (and less than 3 hours from onset)
Door to admission: 180 minutes
What are important tests to order in stroke w/u?
- CT Brain w/o
- EKG
- Glucose
- Labs: CBC, chemistries, PT/INR, aPTT, and cardiac markers
What is the main reason that CT brain w/o contrast is ordered in suspected stroke?
R/o ICH
Because radiologic changes associated with stroke are usually not visible on CT for several hours, the most common CT finding in acute ischemic stroke is _____________.
normal brain
rtPA has been FDA approved for use up to ___ hrs after symptom onset. In addition, the American Heart Association has recommended rtPA for use up to ___ hours after symptom onset in a select subgroup of patients.
3
4.5
What are some tPA exclusion criteria? (read)
Exclusion criteria
- Significant head trauma or prior stroke in previous 3 months
- Sx suggest SAH
- Arterial puncture at noncompressible site (internal/major organ) in previous 7 days
- H/o previous ICH
- Intracranial neoplasm, AVM, or aneurysm
- Recent intracranial or intraspinal surgery
- Elevated BP (systolic >185 mm Hg or diastolic >110 mm Hg)
- Active internal bleeding
- Acute bleeding diathesis
- Platelet count <100,000/mm³
- Heparin received within 48 hours, resulting in elevated aPTT greater than the ULN
- Current use of anticoagulant with INR >1.7 or PT >15 seconds
- Current use of direct thrombin inhibitors or direct factor Xa inhibitors with elevated laboratory tests
- Blood glucose concentration <50 mg/dL (2.7 mmol/L)
- CT demonstrates multilobar infarction (hypodensity >1/3 cerebral hemisphere)
Relative exclusion criteria:
- Only minor or rapidly improving stroke symptoms (clearing spontaneously)
- Pregnancy
- Seizure at onset with postictal residual neurological impairments
- Major surgery or serious trauma within previous 14 days
- Recent GI or GU hemorrhage (within previous 21 days)
- Recent acute MI (within previous 3 months)
- Age < 18 y/o
What should you monitor for after tPA administration? (1)
ICH sx
If a stroke pt doesn’t make it to tPA w/in the 4.5 hr window, what are 3 alternative therapies?
- Intra-arterial thrombolytic therapy,
- Mechanical thrombectomy
- Intracranial angioplasty and stenting in the setting of a clinical trial.
*In stroke pts, BP should be maintained below ___/___ mm Hg in the first 24 hours after receiving thrombolytic therapy.
180/105 mmHg
- The ideal BP range for acute stroke patients not receiving thrombolytic therapy has not yet been determined
Although not a hard rule, for acute stroke patients who do not have other medical conditions requiring aggressive blood pressure control and not undergoing thrombolytic therapy, antihypertensive treatment should not be initiated unless blood pressure exceeds ___/___ mm Hg.
220/120 mmHg
In those who did not receive tPA, administration of _________ within ___ hours after stroke has been shown to improve outcomes by reducing the rate of early recurrent stroke.
Aspirin
24-48 hrs
At least how long should you wait to Rx ASA in someone who received tPA?
24 hrs
What are the 2 most common viruses to cause aseptic meningitis?
Enteroviruses and echoviruses are the most common
- herpes simplex virus (HSV)
- drugs/toxins
Encephalitis is an infection of the brain parenchyma causing inflammation within the CNS and is often due to _________.
viral infxn
- HSV most treatable cause
List as many causes of aseptic meningitis that you can.
- drugs,
- rheumatologic conditions,
- viruses (HIV, HSV)
- parasitic infections,
- fungal infections,
- malignancy,
- Syphilis,
- Lyme disease,
- Rocky Mountain Spotted Fever,
- Ehrlichiosis,
- autoimmune diseases
*Commonly reported descriptions of patients with meningitis typically include the classic clinical triad of:
- fever
- neck stiffness
- AMS
List some possible sx of meningitis in an infant.
nonspecific, include irritability, lethargy, poor feeding, rash, or a bulging fontanelle
The clinical presentation of patients with encephalitis can be similar to patients with meningitis, including fever, headache, or stiff neck, but the diagnosis of encephalitis is characterized by the presence of _____________.
AMS or neurologic symptoms
What is Kernig’s sign?
flexing the hip and extending the knee to elicit pain in the back and the legs
What is Brudzinski’s sign?
passive flexion of the neck elicits flexion of the hips
Petechiae and purpura are classically associated with _______________ meningitis.
meningococcal
_______________ is the preferred diagnostic procedure in patients with suspected bacterial meningitis or encephalitis.
LP
- With what presentations of suspected meningitis should you order a CT Brain before doing an LP?
- *Why?
AMS, new onset seizures, an immunocompromised state, focal neurologic signs, or papilledema.
- Identify pts w/contraindications to LP such as an occult mass from infection or brain tumor, or signs of brain shift or herniation.
What is the major LP finding that is diagnostic for meningitis/encephalitis?
^ WBC
- Describe the following expected CSF findings in BACTERIAL meningitis:
- Opening pressure
- WBC
- PMNs
- Glucose
- Protein
- Gram stain
- Opening pressure: elevated
- WBC: Lots (1,000 to 10,000)
- PMNs: Most (> 80%)
- Glucose: Reduced
- Protein: Elevated
- Gram stain: Positive
- Describe the following expected CSF findings in VIRAL meningitis:
- Opening pressure
- WBC
- PMNs
- Glucose
- Protein
- Gram stain
- Opening pressure: normal
- WBC: < 300
- PMNs: 1-50%
- Glucose: Normal
- Protein: Normal
- Gram stain: Negative
- Describe the following expected CSF findings in FUNGAL meningitis:
- Opening pressure
- WBC
- PMNs
- Glucose
- Protein
- Gram stain
- Opening pressure: elevated
- WBC: < 500
- PMNs: 1-50%
- Glucose: Reduced
- Protein: Elevated
- Gram stain: Negative
How are CSF studies similar or different from meningitis in encephalitis?
CSF studies for patients with encephalitis will lead to similarly abnormal results with elevated WBCs in the CSF, generally with a *lymphocytic predominance. Results may also reveal increased numbers of RBCs in the CSF due to neuronal cell death leading to edema, hemorrhage, and necrosis
*What is the empiric therapy for patients with suspected bacterial meningitis for neonates to < 1 month old?
Ampicillin and Cefotaxime
- Alternative: Ampicillin and Gentamicin
*What is the empiric therapy for patients with suspected bacterial meningitis for infants 1-3 months old?
Ampicillin and Cefotaxime
*What is the empiric therapy for patients with suspected bacterial meningitis for children >3 months old?
*Dexamethasone (consider initiating before first dose of antibiotics) and (Cefotaxime or Ceftriaxone) and *Vancomycin
*What is the empiric therapy for patients with suspected bacterial meningitis for adults < 50 years old?
*Dexamethasone (consider initiating before first dose of antibiotics) and (Cefotaxime or Ceftriaxone) and *Vancomycin
*What is the empiric therapy for patients with suspected bacterial meningitis for adults > 50 years old?
*Dexamethasone (consider initiating before first dose of antibiotics) and (Cefotaxime or Ceftriaxone) and *Vancomycin and *Ampicillin
When treating meningitis, remember to add ________ in cases where HSV encephalitis is suspected.
Acyclovir
The treatment for most cases of encephalitis is:
Supportive care
- HSV encephalitis is the only cause of this disease with a specific treatment, and IV acyclovir is recommended
*When a CT scan is necessary in meningitis w/u, what should you do while waiting for CT results?
Draw blood cultures and administer steroids and appropriate antibiotics BEFORE the LP
Differentiate generalized vs focal (partial), and simple partial vs. complex partial seizures.
- Generalized: involving both hemispheres of the brain with loss of consciousness
- Focal (partial): only one hemisphere is involved.
> Simple partial: when cognition is not impaired
> Complex partial: when cognition is impaired
What is a partial seizure with secondary generalization?
When focal seizures generalize to involve both cerebral hemispheres
List some common PE signs to look for in suspected seizure.
- Common findings:
> postictal confusion that resolves while in the ED
> evidence of tongue trauma from biting
> urinary or bowel incontinence. - Minor head trauma may be present
What is Todd’s paralysis?
A focal neurologic deficit mimicking a stroke seen after seizures
What are some s/sx of a seizure induced by ETOH withdrawal, drug use, or hypoglycemia?
- Tachycardia
- Diaphoresis
- Tremulousness
- Anxiety
*What defines status epilepticus? (2)
- Seizure of greater than 5 minutes duration
or - Two or more seizures in a row without a return to baseline.
Etiologies of secondary, or reactive, seizures include:
Hypoglycemia (most common cause of reactive seizure) Hyponatremia Alcohol withdrawal Trauma Drugs/Toxins Tumor Infection (e.g., meningitis, encephalitis, CNS abscess) Eclampsia
- For new-onset, first-time seizure, the only lab/studies routinely recommended in the ED are: (3), and what are you r/o’ing???
- *What 2 additional should they have as an outpatient?
- Chemistry panel (r/o hyponatremia, r/o hypoglycemia)
- Pregnancy test (r/o eclampsia)
- CT Brain (r/o intracranial lesions)
Outpatient:
- MRI
- EEG
While only chem panel and u-preg is recommended for 1st time seizures, patients in status epilepticus should receive a more complete laboratory profile including _________ (1).
LP
While all first-episode seizures should get a CT Brain, patients with recurrent seizures should undergo head CT scan if:
- a change in their seizure pattern
- significant trauma
- fever
- prolonged postictal time
- new neurological deficit
- other concerning sx
In a seizure pt, head CT scan should be performed (before/after) LP.
Before
- to rule out an intracranial lesion that may cause herniation during LP
All female patients presenting with seizure or possible seizure must be assessed for ___________.
Pregnancy (r/o eclampsia)
What are some s/sx of eclampsia?
- vision complaints,
- edema of the face, hands, and feet,
- proteinuria on urine analysis,
- hypertension
Which TB drug can cause seizures?
isoniazid
As many as ___% of patients initially thought to have pseudoseizure are eventually diagnosed with a true seizure disorder.
25%
*What are some clues of a pseudoseizure?
- rhythmic, controlled shaking activity,
- ability to talk or follow commands during the seizure,
- recall of a seizure that involves both sides of the body,
- lack of a postictal period.
Tx of seizure?
Benzos, benzos, and more benzos (usually lorazepam)
- IV preferred
Review the 1st, 2nd, and 3rd line meds for seizure tx.
- First line: benzodiazepines (usually lorazepam)
- Second line: fosphenytoin/phenobarbital/valproic acid
- Third line: versed/pentobarbital/propofol infusions
What benzos can be given IM, when IV difficult to access?
lorazepam, midazolam, and diazepam
- Rectal also available at some EDs
Review a common lorazepam dosing regimen for seizure tx.
2 mg of lorazepam or midazolam (5 mg of diazepam) every 2-5 min until seizures are controlled.
True or fales:
Patients in status epilepticus will usually need to be intubated to control the airway.
True
*What is the specific tx for a seizure due to eclampsia?
Magnesium sulfate
*What is the specific tx for a seizure due to isoniazid?
Pyridoxine
What is the specific tx for a seizure due to hypernatremia?
Hypotonic saline
What is the specific tx for a seizure due to hypoglycemia?
Dextrose
____________________ is the most common cause of recurrent seizures
Medication noncompliance
