light headedness and syncope

Question 1

echocardiogram with evidence of right heart strain is ____ but not _____ for PE

Answer 1

suggestive but not definitive

Question 2

types of orthostatic hypotension syncope

Answer 2

1. drug induced
2. postural tachycardia syndrome (POTS)
   * common in young female assoc with chronic fatigue syndrome and MVP. sx: severe orthostatic intolerance with marked tachycardia
3. autonomic failure (primary or secondary)
4. volume depletion
   - sx: hypotension, tachycardia, hx of volume/blood loss, dehydration on exam

Question 3

most VTE arise from

Answer 3

lower extremity proximal veins (iliac, femoral, popliteal)

Question 4

unusual causes of nephrogenic diabetes insidious

Answer 4

-hereditary (seen in kids)
-lithium toxicity
-hypercalcemia
(thiazides are a risk)

Question 5

when to use tilt-table test to assess syncope

Answer 5

• dx vasovagal syncope, or orthostatic hypotension syncope

- avoid in pts with heart DZ

Question 6

3 types of reflex syncope

Answer 6

1. carotid sinus syndrome
   - common in elderly male with CAD; brought on by turning head, shaving tight shirt collar; test with carotid massage
2. situational (brought on by defecation, coughing, GI stimulation, urination, after meals, after exercise)
   * will have hx of similar episodes
3. vasovagal - (brought on by fear, heat, noxious stimuli, pain, stress, i.e SNS)
   - prodromal sx (diaphoresis, dizziness, nausea), precipitating factors

Question 7

tx for hypernatremia

Answer 7

replace free water deficit (encourage water to pt or give IV D5W)

Question 8

AND failure pts ten to have ____ HTN but ____ when upright

Answer 8

supine HTN , upright hypotension

Question 9

risk factors for orthostatic hypotension syncope

Answer 9

1. elderly
2. carotid stenosis
3. certain meds (BB, narcotics, alcohol, antidepressants, directics, PDE-I)

Question 10

how to dx Diabetes insipidus

Answer 10

24 hour urine volume collection confirms presence of polyuria
-usirne osm <300 suggest DI (can’t concentrate it)
-water deprivation test with vasopressin administration
(should increase urine OSM in NL pts or those with central DI, but little/no change if neprhogenic DI)

Question 11

tilt table testing POTS results

Answer 11

• sustained increased heart rate

- NO hypotension present (no drop in BP)

Question 12

hypothesized pathophysiology of POTS

Answer 12

1. impaired SNS vasoconstriction --> to venous pooling
leading to: 
-hypovolemia 
-deconditioning 
-hyperadrenergic state

Question 13

T/F compression socks can be used as tx for reflex and orthostatic syncope

Answer 13

yes

Question 14

three major types of syncope

Answer 14

1. cardiac syncope (HIGHEST in SCD)
2. reflex syncope (neural mediated- vasovagal)
3. orthostatic hypotension syncope

Question 15

how to tx HCM

Answer 15

-asx pts don’t need tx
-sx patients:
1. BB, or non-dihydropyridine CCB (decrease O2 demand)
2 direuctics (fluid retention)
3. ICD (implantable cardioverter defibrillator) if high risk for SCD
4. severe cases - surgery (septal myomectomy or septal alcohol ablation; mitral valve replacement)

Question 16

causes of cardiac syncope

Answer 16

structural cardiac dz (AS, HCM, tampondpe, tumor) 
vascular dz (pulmonary embolism, severe pulm HTN, aortic dissection)

Question 17

ADH is released in response to

Answer 17

osmotic and non osmotic stimuli

• serum osmolality detected by osmoreceptors in anterior hypothalamus
• decreases in BP or increase in BV detected by baroreceptors in atrium

Question 18

ADH binds to ___ in the collecting duct and has what effect

Answer 18

binds to V2 receptors and increases cAMP which leads to insertion of AQP2 and urea transporters (INCREASE WATER AND UREA REABSORPTION)
-this is why urea levels go up in dehydration

Question 19

important questions to ask after a syncope episode

Answer 19

did you have nay jerking? head turning? tongue bitting? post-ictla confusion ? (seizure)
did you have any slurred speech, weakness, difficulty swallowing after? (stroke)
PMH? PSH ?
current meds?
DM? check BG after? (hypo/hyperglycemic)
BP before and after?
PFH?

Question 20

pharmologic tx for orthostatic hypotension syncope

Answer 20

flurocortisone (aldosterone agonist )
midodrine (alpha Agonist)
caffeine, etc

Question 21

what causes orthostatic hypotension syncope

Answer 21

NL when standing the decrease preload (degreased BP) to the heart triggers baroreceptor reflex to increase PVR and venous return to increase BP - no syncope

in OHS- autonomic reflex failure or severe intravascular depletion leads to significant drop in BP with postural changes and no reflex increase

Question 22

tx for DI

Answer 22

central
-vasopressin 
nephrogenic
-thiazides
-NSAIDS
-Vasopressin (bc incomplete resistance)