Pulmonary Embolism

1
Pulmonary Embolism

• Suspecting and diagnosing acute pulmonary embolism

2
Signs and Symptoms of PE

• Dyspnea (sudden or gradual onset)
• Orthopnea
• Chest pain (usually pleuritic)
• Tachycardia
• Hypoxia
• Coughing/hemoptysis
• Syncope
• Anxiety
• Tachypnea
• Diaphoresis
• Evidence of DVT
• Signs of RV overload on EKG (often nonspecific
  ST/T abnormalities)
• Fever

3
Risk factors for PE

• Surgery or trauma
• Prolonged immobility 0r obesity
• Hypercoagulable state (malignancy, peripartum,
  nephrotic syndrome, thrombophilias)
• Smoking
• Previous DVT
• Indwelling venous catheter
• Medications (HRT, estrogen-containing compounds,
  chemotherapy, SERMs)
• Increasing age

4
PERC Rule

• Age lt 50
• Pulse oximetry gt 94
• Heart rate lt 100 bpm
• No prior history of PE
• No hemoptysis
• No estrogen use
• No unilateral leg swelling or clinical suspicion
  for DVT
• No surgery or trauma (requiring hospitalization
  or intubation) within the last 4 weeks
• If all are true, then no D-dimer is necessary and
  PE is ruled out.
• If one or more is false, D-dimer is ordered. If
  D-dimer is positive, CTA is indicated.
• If clinical suspicion is high despite
  results of PERC rule or D-dimer, further testing
  is indicated.

5
Hints on CXR to suggest PE

• Hamptons hump
• Pulmonary oligemia (Westermarks sign)
• Abrupt amputation of hilar artery (Knuckle sign)
• Elevated diaphragm(s)/volume loss
• Atelectasis (Fleischner lines)
• Pleural effusion
• Cardiomegaly
• Interstitial edema

6
Hamptons hump
7
Westermarks sign
8
Knuckle sign
9
Fleischner lines
10
ACR Appropriateness Criteria
11
V/Q Scan with PE
12
CTA with PE
13
Resources

• http//www.med.cmu.ac.th/student/rad/chest/p_embol
  ism.htm
• http//www.e-radiography.net/radpath/p/pe2.htm
• http//www.guideline.gov/summary/summary.aspx?doc_
  id10600
• http//ajrccm.atsjournals.org/cgi/content/full/159
  /3/864?viewfullpmid10051264 
• http//www.rhqn.org/resources/The Quandary of
  Considering Acute Pulmonary Embolism.doc
• http//acsearch.acr.org/ProceduresList.aspx?tid69
  068vid3072082