Neurology Flashcards
What is the massive transfusion protocol?
administration of PRBC, FFP, and Platelets in 1:1:1 ratio in order to avoid coagulation in patient with hemorrhagic shock after a massive trauma
What is adverse long term effect of metformin in some patients?
vit b12 deficiency due to alteration in calcium homeostasis leading to impaired absorption of vit b12 in the terminal ileum
How to diagnose Guillain barre syndrome?
1) Lumbar puncture for CSF analysis. High protein (Albuminocytologic dissociation) with normal WBCs and glucose
Or
2) Nerve conduction study and Electromyography
What is Miller Fisher syndrome?
It is a variant of Guillain barre syndrome. It has ophthalmoplegia, ataxia and areflexia.
What is subacute combined degeneration syndrome?
Seen in Vit b12 deficiency. Dorsal column and lateral corticospinal tracts are affected. Sxs are diminished vibration, proprioception, light touch and spastic paresis, enhanced reflexes
How to diagnose for myasthenia gravis?
Bedside ice pack test (improvement in sxs) for screening. Confirmation with acetylcholine receptor antibody. Also thymoma on chest CT.
What is the treatment for MG?
Pyridostigmine which is a Acetylcholine esterase inhibitor. Increases the availability of Ach at NMJ. Corticosterioids are also helpful. Thymectomy is also helpful.
What is the pathogenesis of Lambert Eaton myasthenic syndrome?
Autoantibodies against voltage gated calcium channels which subsequently results in decreased release of Ach from the presynaptic end in the NMJ.
What is the pathogenesis of Tetanus?
C tetini toxin blocks the release of inhibitory neurotransmitters like glycine and GABA across the presynaptic cleft, leading to fever, painful muscular spasms, and trismus (Lock Jaw)
What is the pathogenesis of vasovagal syncope?
increased parasympathetic and decreased sympathetic signalling resulting in arterial and venous vasodilation and decreased heart rate and contractility
How to diagnose ALS?
Electromyography; MRI of head and spinal cord (to exclude other causes)
What is the pathogenesis of Benign paroxysmal positional vertigo (BPPV)?
Crystalline debris (canalith) in the semicircular canals that disrupt the normal flow of fluid in the vestibular system. Diagnosed with provocative head positioning maneuver to illicit vertigo and nystagmus.
What are CYP450 inducers?
Barbiturates, Antiepileptics and smoking and EtOH
Pathogenesis of acute intermittent porphyria?
Reduced activity of Porphobilinogen (PBG) deaminase resulting in accumulation of neurotoxic heme pathway intermediates such as ALA and PBG
What are symptoms of Acute intermittent porphyria?
Abdominal pain, peripheral neuropathy, autonomic dysfunction, neuropsychiatric sxs.
Red tinged urine due to PBG
Diagnosis of Acute intermittent porphyria?
Elevated levels Porphobilinogen and porphyrins in Urine and serum
What does Pronator drift indicate?
pronator drift is sensitive and specific for upper motor neuron or pyramidal/corticospinal tract disease
What are risk factor of multiple sclerosis?
young caucasian women, vitamin D deficiency, HLA-DRB1, smoking
Why is estrogen containing contraceptions are contraindicated in patients with migraine?
Due to increased risk of ischemic stroke
What are the abortive therapies for Migraine?
Triptans, NSAIDs, Ergotamine, acetaminophen and antiemetics (prochlorperazine, metoclopramide)