Internal Med- Neurology Flashcards
How would you define stroke?
What is the etiology?
Stroke is the sudden onset of a neurological deficit from the death of brain tissue.
Stroke is caused by a sudden blockage in the flow of blood to the brain in 85% of cases and by bleeding in 15% of cases.
Where can the Emboli that cause a stroke originate from?
- Heart: atrial fibrillation, valvular heart disease, or a DVT paradoxically getting into the brain through a patent foramen ovale (PFO).
- Carotid stenosis
Which blood vessel is usually affected by a stroke?
Middle cerebral artery (MCA) stroke (more than 90% of cases):
What Sx does a Middle cerebral artery (MCA) stroke elicit?
-Weakness or sensory loss on the opposite (contralateral) side of the lesions causing stroke.
-Homonymous hemianopsia: loss of visual field on the opposite side of the stroke. A left-sided MCA stroke results in loss of the right visual fields. The eyes can’t see the right side, so the eyes deviate to the left. Hence the eyes “look towards the side of the lesion.”
-Aphasia if the stroke occurs on the same side as the speech center. This is the left side in 90% of patients.
Speech is controlled by the same side as “handedness.” Right-handed people (left brain dominant) have a speech center on the left-hand side of the brain.
What Sx does an Anterior cerebral artery (ACA) stroke elicit?
- Personality/cognitive defects such as confusion
- Urinary incontinence
- Leg more than arm weakness
What Sx does a Posterior cerebral artery (PCA) stroke elicit?
Ipsilateral sensory loss of the face, 9th and 10th cranial nerves
Contralateral sensory loss of the limbs
Limb ataxia
What is the best initial test when suspecting a stroke?
What is the most accurate test?
The best initial test in any kind of stroke is a CT scan of the head without contrast. The most accurate test is an MRI. CT scan is done first, not because it is the most sensitive test for stroke, but in order to exclude hemorrhage as a cause of the stroke prior to initiating treatment.
What is the latest time that thrombolytics can be initiated in a Pt with a Stroke?
4,5 hours after the onset of stroke.
How would you Mgx nonhemorrhagic (Ischemic) and hemorrhagic stroke?
- Less than 3 hours since onset of stroke: thrombolytics (TPA)
- More than 3 hours since onset of stroke: aspirin
- Hemorrhagic stroke: nothing. Hemorrhagic stroke has no treatment to reverse it. Surgical drainage will not help outside posterior fossa.
What is your next best step if a Pt with a stroke is already on Aspirin?
Add dipyridamole
or
Switch to clopidogrel
If Pt’s Sx (stroke Sx) last <24hr and then resolve, what is the next best step in Mgx?
Its a TIA so Tx with;
Aspirin + dipyridamole
or
Switch to clopidogrel if Pt is already on Aspirin
If a Pt you suspect has a stroke comes in after 4.5 hours, what is the next best step in Mgx?
Remove clot via catheter. Catheter retrieval pulls the clot out like a corkscrew. It is useful up to 6–8 hours after stroke, but angioplasty is not. Angioplasty would rupture the vessel.
Besides blood thinners (aspirin or clopidogrel), which medication should be given to every patient with a stroke?
A Statin.
Although target-based therapy for lipid management is unclear at this time, we want to bring the LDL to at least under 70.
How does acute blood appear on a CT? If there is a need for contrast, what type of contrast is needed?
Acute blood appears white on a CT scan. Contrast is not needed to detect blood.
What tests can be done to evaluate causes of a Stroke?
- Echocardiogram
- EKG
- Holter monitor (24 to 48 hour ambulatory EKG)- If the initial EKG is normal, a Holter monitor should be performed to detect atrial arrhythmias with greater sensitivity.
- Carotid duplex ultrasound
In a Stroke Pt, if the Echocardiogram reveals a thrombi, what is the next best step in Mgx?
Heparin followed by Warfarin to an INR of 2 to 3. Rivaroxaban and Dabigatran are alternative medications.
In a Stroke Pt, if the EKG reveals Atrial fibrillation or flutter, what is the next best step in Mgx?
Tx with a NOAC or warfarin as long as the arrhythmia persists.
In a Stroke Pt, if the EKG is normal, what is the next best step?
a Holter monitor should be performed, as it detects atrial arrhythmias with greater sensitivity.
In a Stroke Pt, if the Carotid duplex ultrasound reveals stenosis more than 70%, what is the next best step in Mgx?
Endarterectomy.
If the stenosis is 100%, however, no intervention is needed. There is no point in opening a passage that is 100% occluded.
In a Stroke Pt, if the Carotid duplex ultrasound reveals stenosis less than 50%, what is the next best step in Mgx?
No intervention is needed.
Which of the following has greater value in the Mgx of Stroke, Endarterectomy or Angioplasty and Stenting?
Endarterectomy is superior to carotid angioplasty and stenting.
What are some of the clinical features that would make a Migraine be the cause of a Pt’s headache?
Visual disturbance (flashes, sparks, stars, luminous hallucinations), photophobia, aura, relationship to menses, association with food (chocolate, red wine, cheese). May be precipitated by emotions
What are some of the clinical features that would make a Tension headache be the cause of a Pt’s headache?
A headache with no physical findings.
What are some of the clinical features that would make a Cluster headache be the cause of a Pt’s headache?
Frequent, short duration, high intensity headaches, with men affected 10 times more than women. Tearing eye with rhinorrhea; Horner syndrome occasionally
What are some of the clinical features that would make Giant cell (temporal) arteritis be the cause of a Pt’s headache?
Visual disturbance, systemic symptoms such as muscle pain, fatigue, and weakness. Jaw claudication. Tenderness of the temporal area
What are some of the clinical features that would make Pseudotumor cerebri be the cause of a Pt’s headache?
Obesity, venous sinus thrombosis, oral contraceptives, and vitamin A toxicity. Mimics a brain tumor with nausea, vomiting, and visual disturbance.
How would you Dx Pseudotumor cerebri?
CT or MRI without an intracranial mass lesion and a lumbar puncture (LP) showing increased pressure. Only the pressure is abnormal. The CSF itself is normal.
What is the most accurate Dx test for Giant cell arteritis and how would you Mgx it?
It is associated with a markedly elevated ESR and the most accurate test is a biopsy.
It is critical to start steroids (prednisone) without waiting for biopsy in giant cell arteritis.
How would you Mgx a Tension headache?
NSAIDs and other analgesics
How would you Mgx a Migraine?
Triptans (sumaptriptan, eletriptan, almotriptan, zolmitriptan) or ergotamine as abortive therapy
How would you Mgx a Cluster headache?
Triptans, ergotamine, or 100% oxygen as abortive therapy
How would you Mgx a headache from Pseudotumor cerebri?
weight loss; acetazolamide to decrease production of cerebrospinal fluid. Steroids help. Repeated lumbar puncture rapidly lowers intracranial pressure. Place a ventriculoperitoneal shunt or fenestrate (cut into) the optic nerve if medical therapy does not control it.
What would you give to provide prophylaxis for Cluster headaches?
Verapamil
What is the indication for prophylactic Tx for Migraines?
What is the best preventive therapy?
More than 3 migraine headaches per month.
Propranolol. Other preventive medications are: -Calcium channel blockers -Tricyclic antidepressants (amitriptyline) -SSRIs, topiramate -Botulinum toxin injections
What is Trigeminal Neuralgia and what are its clinical features?
Trigeminal neuralgia is an idiopathic disorder of the fifth cranial nerve resulting in severe, overwhelming pain in the face. Attacks of pain can be precipitated by chewing, touching the face, or pronouncing certain words in which the tongue strikes the back of the front teeth. Patients describe the pain as feeling as if a knife is being stuck into the face.
How would you Tx Trigeminal Neuralgia?
Oxcarbazepine or Carbamazepine
What is Postherpetic Neuralgia and how is it Mgx?
It’s a pain syndrome from Herpes zoster reactivation (Shingles),
after resolution of the vesicular lesions in about 15% of cases.
Tx-
To reduces incidence; acyclovir, famciclovir, or
valganciclovir, *not steroids
For pain; tricyclic antidepressants, gabapentin, pregabalin, carbamazepine, or phenytoin
When is the Zoster vaccine indicated and how is it different from the Varicella vaccine?
Zoster vaccine is indicated in all persons above the age of 60 to prevent herpes zoster (shingles). This vaccine is similar to the varicella vaccine routinely administered to children to prevent chicken pox or varicella, except that the dose is much higher.
In most cases, why is an EEG not the right answer for a Pt with Seizures?
There is no point in doing an EEG to identify the cause of a seizure if there is a clear metabolic, toxic, or anatomic defect causing the seizure. In other words, what would be the point of doing an EEG if the patient had hyponatremia or a brain lesion? You have already found the cause of the seizure.
What is the difference between Seizures and Epilepsy?
Seizures of unclear etiology are called epilepsy. If there is a clear cause, it is not epilepsy.
What is the initial therapy for a persistent seizure (Status Epilepticus)?
A benzodiazepine such as lorazepam or diazepam intravenously.
If a persistent seizure (Status Epilepticus) persists after giving a benzodiazepine, what is the next best step?
Give phenytoin or fosphenytoin
What is the difference between phenytoin and fosphenytoin?
Fosphenytoin and phenytoin have the same efficacy, but fosphenytoin has fewer adverse effects compared to phenytoin. Like lidocaine, phenytoin is a class 1b antiarrhythmic medication. When given intravenously, it is associated with hypotension and AV block. Fosphenytoin does not have these adverse effects and can therefore be given more rapidly.
If benzodiazepines and fosphenytoin do not stop a seizure, what is the next best step?
Administer phenobarbital
If benzodiazepines, fosphenytoin and phenobarbital do not stop a seizure, what is the next best step?
Use a neuromuscular blocking agent such as succinylcholine, vecuronium, or pancuronium to allow you to intubate the patient and then give general anesthesia such as midazolam or propofol. The patient must be placed on a ventilator before the administration of propofol, which can stop breathing.
What are the 4 different levels of therapy (in order) for persistent seizures (Status Epilepticus)?
- Benzodiazepine
- Fosphenytoin
- Phenobarbital
- General anesthesia (Preceded by a neuromuscular blocking agent such as succinylcholine to allow you to intubate the patient)
How can seizures be classified?
- Generalized seizures (grand-mal)- tonic-clonic seizures have varying phases of muscular rigidity (tonic) followed by jerking of the muscles of the body for several minutes (clonic).
- Partial seizure- Like the name implies, this is a seizure that is focal to one part of the body. For instance, a patient may have a seizure that is limited just to an arm or leg. Partial seizures can either be simple (intact consciousness) or complex (loss or alteration of consciousness).
- Absence (petit-mal) seizure: Consciousness is impaired only briefly. The patient often remains upright and gives a normal appearance or seems to be staring into space. Absence seizures occur more often in children.
How would you Mgx epilepsy?
levetiracetam, phenytoin, valproic acid, and carbamazepine all have nearly equal efficacy. Levetiracetam has the fewest adverse effects.
It is not necessary to begin antiepileptic drugs for a single seizure. What are some of the exceptions in which you should start after a single seizure?
- Presentation in status epilepticus or with focal neurological signs
- Abnormal EEG or lesion on CT
- Family history of seizures
Which drug is best for absence seizures?
Ethosuximide
Can we Tx Alcohol withdrawal seizures with long-term antiepileptic
drugs? If so, which drug?
Alcohol withdrawal seizures are not treated with long-term antiepileptic drugs.
In what situation can a Pt discontinue seizure medication?
What is the best way to tell if there will be reoccurrence?
The standard of care is to wait until the patient has been seizure-free for 2 years.
A sleep deprivation EEG is the best way to tell if there is the possibility of recurrence. Sleep deprivation can elicit abnormal activity on an EEG, but the test lacks high sensitivity.
A 38-year-old man is evaluated for seizures. He achieves partial control with the addition of a second antiepileptic medication. He drives to work each day.
What do you do about his ability to drive?
a. Confiscate his license.
b. Allow him to drive if he is seizure-free for 1 year.
c. Allow him to drive as long as his seizure history is noted on his license.
d. Recommend that he find an alternate means of transportation.
e. Do not let him leave the office unless he is picked up by someone; no further driving.
f. Allow him to drive as long as he is accompanied.
*D.
You do not have the right, as a physician, to confiscate a patient’s driver’s license. The rules on seizure disorder and motor vehicles vary from state to state. Reporting his condition to the department of motor vehicles does not have the same clarity as, for instance, reporting child abuse, in which the doctor is legally protected for all reports made in good faith. You cannot hold a patient (incarcerate) for seizures in the way that you can for tuberculosis. Being accompanied in a car does not prevent seizures.
Give a briefing of Subarachnoid hemorrhage (SAH)?
It is caused by the rupture of an aneurysm that is usually located in the anterior portion of the circle of Willis. Aneurysms are present in 2% of routine autopsies. The vast majority never rupture. They are more frequent in those with:
-Polycystic kidney disease
-Tobacco smoking
-Hypertension
-Hyperlipidemia
-High alcohol consumption
What provokes a rupture is not clear in the majority of cases.
What clinical features would make Subarachnoid hemorrhage (SAH) the most likely Dx?
Sudden onset of an extremely severe headache with meningeal irritation (stiff neck, photophobia) and fever.
- Fever is secondary to blood irritating the meninges.
meninges. Loss of consciousness occurs in 50% from the sudden increase in intracranial pressure. Focal neurological complications occur in as many as 30%.
When suspecting Subarachnoid hemorrhage (SAH), what is best initial test?
What is the most accurate test?
Best initial test: CT without contrast (95% sensitive).
Most accurate test: lumbar puncture showing blood. *LP is necessary only for the 5% that have a falsely negative CT scan.
What are some of the findings you would expect to find in the CSF of a Pt with Subarachnoid hemorrhage (SAH)?
How would you ddx some of the changes with those of meningitis?
Xanthochromia is a yellow discoloration of CSF from the breakdown of red blood cells (RBCs) in the CSF.
The CSF in SAH will have an increased number of WBCs, which can mimic meningitis. However, the ratio of WBCs to RBCs will be normal in SAH. Normal ratio: **One WBC for every 500 to 1,000 RBCs.
When the WBC count exceeds the normal ratio, you should suspect meningitis.
Why is a contrast not necessary when looking for blood on a CT or MRI?
Contrast on CT or MRI improves detection of mass lesions such as cancer or abscess but not blood.
What ECG finding is common with Intracranial Bleeding?
Large or inverted T waves suggestive of myocardial ischemia (cerebral T waves). This is thought to be from excessive sympathetic activity.
In case of Intracranial Bleeding, how do you precisely tell which vessel ruptured?
CT angiography, standard angiography with a catheter, or MRA.
How would you Mgx Intracranial Bleeding?
- Nimodipine (calcium channel blocker) prevents subsequent ischemic stroke.
- Embolization (coiling) uses a catheter to “clog up” the site of bleeding to prevent a repeated hemorrhage. An interventional neuroradiologist places platinum wire into the site of hemorrhage. Embolization is superior to surgical clipping in terms of survival and complications.
- Ventriculoperitoneal shunt: SAH is associated with hydrocephalus. Place a shunt only if hydrocephalus develops.
- Seizure prophylaxis: Phenytoin is generally given to prevent seizures. If the question asks “Which of the following is indicated?” antiepileptic
therapy is the answer, although controversial.
A woman comes to the emergency department with a severe headache starting one day prior to admission. On physical examination she has a temperature of 103°F, nuchal rigidity, and photophobia. Her head CT is normal. LP shows CSF with 1250 white blood cells and 50,000 red blood cells.
What is the most appropriate next step in the management of this patient?
a. Angiography.
b. Ceftriaxone and vancomycin.
c. Nimodipine.
d. Embolization.
e. Surgical clipping.
f. Repeat the CT scan with contrast.
g. Neurosurgical consultation.
*B.
The number of WBCs in the CSF in this patient far exceeds the normal ratio of 1 WBC
to each 500 to 1000 RBCs. With 50,000 RBCs, there should be no more than 50 to 100 WBCs. The presence of 1250 WBCs indicates an infection, and ceftriaxone and vancomycin are the best initial therapy for bacterial meningitis. Contrast is not useful when looking for blood. Try never to answer “consultation” for anything.
