Syncope

Syncope – Eric Hall

Background

  • Transient loss of consciousness (TLOC) from cerebral hypoperfusion
  • Pre-syncope should be addressed in the same way as syncope
  • Pathogenesis:
      •  
    • Reflex/vasovagal ~20-60%: identifiable triggers such as shaving, straining/pooping, usually in older patients
    • Orthostatic hypotension ~10%: more common with older patients, with anti-HTN meds, diuretics, H&N cancer tx, DM, Parkinson’s, MSA, adrenal insufficiency
    • Neurogenic: Consider CVA, TIA, seizure and rarely subclavian steal syndrome
    • Cardiovascular:
      • Mechanical/structural, including aortic stenosis or other valvular disease, HCM, PE, pHTN, ischemia, tamponade
      • Arrhythmia, including block, pauses, WPW, long/short QT as evidence of arrhythmia-mediated syncope
    • Alternate diagnoses: metabolic, intoxication, iatrogenic or medication effect, concussion, and episodes that are not true TLOC (cataplexy, psychogenic)

 

Evaluation

  • CBC, CMP, EKG, telemetry, troponin, BNP if concerned for cardiac etiology, POC blood glucose, UDS, orthostatic vitals
  • Consider (depending on patient’s history): TTE, head imaging, 2-hour EEG (get neuro involved early if concerned for neurologic etiology), TSH + cortisol (random vs AM), infectious workup, stress testing for exertional syncope

 

Management

  • Dependent on cause (see other sections)
  • If presumed diagnosis is autonomic dysfunction, consider consult at VA & VUMC to Autonomics for consideration of oral vasopressor (midodrine, droxidopa), compression stockings, abdominal binder, follow-up, etc
  • On discharge (depending on evaluation/presumed diagnosis) consider also cardiac event monitoring, ambulatory blood pressure monitoring, +/- tilt table testing
  • Driving (TN Driver Improvement, Rule 1340-01-04-.06):
    • TN law does not require any MD to inform the state of TLOC
    • If notified, the state may suspend/decline to re-issue the pt's driver’s license for 6-12 months (if underlying condition controlled, pt is free of TLOC, and the state receives a “favorable medical report” from an MD)
    • Make sure to document all conversations about driving that you have with pts