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3rd Year (Step 2) > Medicine_MUST KNOW > Flashcards

Flashcards in Medicine_MUST KNOW Deck (21)
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1
Q

What does CREST (syndrome) stand for?

A
Calcinosis
Rayaud's phenomenon
Esophageal dysmotility
Sclerodactyly
Telangiectasia
    • ass’d w/ anti-Centromere antibody
    • limited skin involvement, often confined to fingers & face. More benign clinical course.
2
Q

Petechiae vs. Ecchymoses vs. Purpura

A

< 5mm = Petechiae

> 5mm, < 1cm = Purpura

> 1cm = Echymosis

3
Q

Pathophysiology:

Myasthenia Gravis vs. Lambert-Eaton Myasthenic Syndrome

A

MG = autoantibodies to postsynaptic ACh receptor (block, do NOT destroy receptors)

LEMS = Autoantibodies to presynaptic Ca(2+) channel –> dec’d ACh release

4
Q

Cholinomimetic Direct Agonists?

A

Bethanechol, Carbachol, Pilocarpine, Methacholine

5
Q

Acetylcholinesterase-inhibitors?

A

Neostigmine, Pyridostigmine, Physostigmine (CNS), Edrophonium, Donepezil

6
Q

Muscarinic Antagonists?

A

Atropine (eye), Benztropine (CNS), Scopolamine (CNS), Ipra/Tiotropium (resp), Oxybutynin (G/U), Glycopyrrolate (GI/resp)

7
Q

NE: effect on MAP & HR?

A

inc’d MAP
dec’d HR

(all but β-2 agonist)

8
Q

Isoproterenol: effect on MAP & HR?

A

dec’d MAP
inc’d HR

(β-1 & 2 agonist)

9
Q

Clonidine - MOA?

A

centrally acting α-2 agonist

dec’s central symp outflow

10
Q

Clonidine - clinical use?

A

Hypertension, esp. w/ renal disease b/c no decrease in BF to kidneys

11
Q

α-methyldopa - clinical use?

A

Hypertension, esp. w/ renal disease b/c no decrease in BF to kidneys

12
Q

α-methyldopa - clinical use?

A

centrally acting α-2 agonist

dec’s central symp outflow

13
Q

Phenoxybenzamine vs. Phentolamine?

A

Phenoxybenzamine = irreversible, used for Pheochromocytomas before removing tumor

Phentolamine = reversible, give to patients on MAO inhibitors who eat tyramine-containing foods

14
Q

Common triggers/characteristics of Vasovagal (neurocardiogenic) Syncope?

A

Triggers = Prolonged standing, Emotional distress, Painful stimuli

Prodromal Sx = Nausea, warmth, diaphoresis, dizziness

    • due to excessively inc’d vagal tone
    • excellent prognosis
15
Q

Type of Syncope?

- Prodromal Sx of nausea, dizziness, warmth, diaphoresis

A

Vasovagal (neurocardiogenic)

16
Q

Type of Syncope?

Hypokalemia, Hypomagnesemia, meds that cause inc’d QT interval

A

Torsades de Pointes

acquired long QT syndrome

17
Q

Type of Syncope?

Sinus pauses on monitor, prolonged PR interval or QRS duration

A

Sick Sinus Syndrome,
Bradyarrhythmias,
AV-block

18
Q

Myasthenic Crisis Tx?

A
  • Endotracheal intubation
  • w/draw acetylcholinesterase-inhibitors
  • ABX if 2/2 infection (most commonly is)
  • Plasmapheresis or IVIG can also be given to hasten recovery of the MG crisis
19
Q

Serum Anion Gap calculation

A

= [Na+] − ([Cl-] + [HCO3−])

20
Q

Osmol Gap calculation

A

OG = measured serum osmolality − calculated osmolality

Calculated osmolality = 2 x [Na mmol/L] + [glucose mg/dL] / 18 + [BUN mg/dL] / 2.8 + [Ethanol/3.7]

(NB: divisor 18 respectively 2.8 to convert mg/dL into mmol/L)

A normal osmol gap is < 10 mOsm/kg

21
Q

Urine Anion Gap

A

UAG = Urine (Na + K - Cl)

Normal UAG = 20-90

In metabolic acidosis, kidneys secrete NH4+, usually paired w/ Cl-, so a neg UAG means high urine Cl-, which means high NH4 being secreted by kidneys (i.e. met acidosis 2/2 diarrhea)

  • normal UAG in met acidosis suggests a distal RTA (also a met acidosis w/ a persistent urine pH above 5.5 suggests dRTA)