Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

MSII Practice of Medicine > Unit 4 - Syncope > Flashcards

Unit 4 - Syncope Flashcards

1
Q

what can cause transient losses in consciousness?

A
  1. nontraumatic (syncope, epileptic seizure, functional TLOC, rare causes/mimics)
  2. traumatic (concussion)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what is the definition of syncope? its requirements?

A

complete, transient loss of consciousness and postural tone

  • rapid onset
  • complete loss of consciousness and postural tone
  • brief (30 sec to <5 min)
  • spontaneous recovery
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what is cerebral perfusion determined by? dependent on?

A

determined by BP, which is dependent on CO (contractility, blood volume, HR) and vascular tone (autonomic nervous system)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

how much volume do the veins hold?

A

65% of total blood volume

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what is special about arterioles?

A

they are resistance vessels with a wide range of tone and volume

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what are determinants of CO?

A

SV x HR

  • structure
  • LV (end diastolic) volume
  • HR
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what does sympathetic system do for structure?

A

increased contracctility

  • myocardial function (LV EF)
  • hypertrophic obstructive CM / AS (outflow obstruction)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what can cause LV volume changes in syncope?

A
  • hemorrhage
  • renal/adrenal dysfunction
  • dehydration
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

how does tachycardia cause syncope?

A

too little time for LV to fill –> low LV EDV –> decreased CO

  • contraction (systole) time remains fixed irrespective of HR
  • relaxation time decreases as HR increases
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what does increased pooling of blood in extremities/mesentery do to CO?

A

decreases CO

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what is the etiology of syncope?

A
  1. neurally mediated (vasovagal, carotid sinus, situational cough/post-micturation)
  2. orthostatic (drug-induced, ANS failure primary or secondary)
  3. cardiac arrythmia (brady sick sinus or AV block, tachy VT or SVT, long QT syndrome)
  4. structural cardiopulmonary (aortic stenosis, HOCM, pulmonary HTN)
    5 non-cardiovascular (psychogenic, metabolic hyperventilation, neurological)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what is reflex/neurally mediated syncope?

A

abrupt withdrawal of sympathetic tone

  • leads to vasodilation/hypotension and bradycardia
  • vaso-vagal: stress, pain, phobia
  • situational: cough, sneeze, laugh, eat/pee/poop
  • carotid sinus hypersensitivity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what is orthostatic hypotension?

A

inadequate peripheral vasoconstriction in response to orthostatic stress
-drop in BP by 20/10 within 3 minutes of standing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

causes of orthostatic hypotension?

A

DAAD (drugs, autonomic dysfunction, alcohol, dehydration)

  • Drugs: diuretics, sedatives, psychiatric drugs, alpha-blockers (used in BPH)
  • Primary autonomic failure: Parkinson’s multiple system atrophy, Lewy body dementia
  • Secondary autonomic failure: diabetes, amyloidosis, spinal cord injury
  • Alcohol
  • Volume depletion: dehydration/diarrhea, hemorrhage
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what is cardiac syncope caused by?

A
  • bradycardia: drug-induced, electrolyte abnormality, conduction system disease
  • tachycardia: VT or SVT
  • HOCM (systolic murmur)
  • aortic stenosis (systolic murmur)
  • severe CHF (S3/4, lung crackles)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

if you get syncope from sudden noise or extreme emotions, what is a likely diagnosis?

A

long QT syndrome

17
Q

what is syncope prodrome?

A
  • vasovagal: nausea/abdominal pain, dizziness, tinnitus, neck/shoulder pain
  • -may be absent in elderly
  • arrhythmia: none or very brief prodrome, palpitations
  • seizure: deja-vu, hallucinations, sensory aura
18
Q

what are questions to the witness?

A
  • slump over or fall abruptly
  • skin color (cyanotic, pale, flushed)
  • any motor movements
  • pattern of breathing
  • duration of episode
  • mental status post-event
  • incontinence
19
Q

what does syncope post-drome look like?

A

arrhythmia: rapid recovery
vasovagal: may take longer to recover
seizures: post-ictal confusion, neurological deficits

20
Q

what should you look for on physical exam for syncope?

A
  • vitals (supine/standing BP/HR)
  • pallor
  • neck (carotid pulse/bruit, JVP)
  • cardiac (regulatory rate, murmurs)
  • lungs (air entry, wheezing, crackles)
  • neuro (deficits, mentation)
21
Q

what labs should you order for syncope?

A
  • CBC (hematocrit)

- BMP (Na/K, BUN/creatinine)

22
Q

what are high risk features of syncope?

A
  • exercise-induced
  • FH of SCD
  • “drop attacks”
  • abnormal EKG
  • pallor/anemia/electrolyte abnormality
23
Q

what testing should you order for syncope?

A
  • cardiac: echo, rhythm monitoring, EP study
  • neurogenic: tilt-table testing if diagnosis is in doubt
  • neurology: EEG, MRI
24
Q

treatment for neurogenic/vasovagal syncope

A
  • lifestyle modifications: avoid triggers, adequate salt intake/hydration, moderate exercise
  • physical counterpressure: tight stockings, tilt training
  • pharmacology: BB, fludrocortisone, alpha agonists, SSRI (paroxetine)
  • permanent pacemaker: class IIb indication (“possibly useful”)
25
Q

what is treatment for orthostatic hypotension?

A
  • treat the treatable with drugs
  • -midodrine (peripheral alpha agonist)
  • lifestyle changes (adequate hydration, leg exercises before getting up)
  • stockings
  • aids to improve balance (cane, walker)
26
Q

treatment for cardiac syncope

A

high risk and most easily treated

  • brady: pacemaker
  • tachy: ablation
  • HOCM/aortic stenosis: surgery
  • AICD

MSII Practice of Medicine (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions