Pulmonary Embolism (as cause of Acute Dyspnea)

A hard diagnosis.  Seek especially a history of:

  • Sudden Onset Dyspnea  —  Within 30-60 seconds in almost 75% of patients.  When someone remembers the exact moment their dyspnea began, think PE.

Also suspect a PE based on risk factors, & perhaps other clinical findings:

Top Risk Factors for PE

  • Prior Hx of either PE or DVT!!!
  • Immobilization for >3 days.
  • Anesthesia within the last 4 weeks.
  • Active cancer
  • Maybe HIV infection
  • Maybe obese women who smoke & have hypertension

Clinical Findings Suggesting PE

  • Pain/tenderness in medial thigh (? a DVT)
  • Leg redness, heat, swelling (? DVT)
  • Hemoptysis
  • Tachycardia (>100)
  • Tachypnea  (>20)
  • Loud S2 heart sound

Finally, another very predictive parameter: “no other diagnosis more likely.”  If you think a PE is not unlikely, send the patient to an E.D.

E.D. work-up:  stat D-dimer combined with clinical probability score to decide if the case warrants a CT or ventilation/perfusion [V/Q] scan.

See posting Acute Dyspnea – 2.