Alliteration aside, I have wondered for sometime why EMS in general has not adopted some of the scoring criteria for pulmonary embolism. Emergency medicine in general is very algorithm based and paramedics love algorithms. We are not doctors but we can act like them especially when we have a patient that we think might be having a PE. By utilized the 2 scores that we will discuss we can greatly improve patient treatment and continuing of care for our customers.

This week we will discuss all things PE. Make sure you listen to the PE podcasts so that you get some more details about the pathophysiology, treatment, recognition and ECG findings in PE.

So, the second you have a patient and the thought of PE crosses your nugget even for an instant, consider adding this to your assessment

Wells Criteria

  • clinically suspected dvt — 3.0 points
  • alternative diagnosis is less likely than PE — 3.0 points
  • tachycardia (heart rate > 100) — 1.5 points
  • immobilization (≥ 3d)/surgery in previous four weeks — 1.5 points
  • history of dvt or PE — 1.5 points
  • hemoptysis — 1.0 points
  • malignancy (with treatment within 6 months) or palliative — 1.0 points

There are many calculators to help you with this for example (Wells Criteria Calculator). What you are going to do is ask yourself and the patient these questions and score it. The traditional scoring method will lead you to prognostics.

  • Score >6.0 — High (probability 59%)
  • Score 2.0 to 6.0 — Moderate (probability 29%)
  • Score <2.0 — Low (probability 15%)

Generally if the score is >3 than PE might still be in the cards. Look for other things such as ECG findings to help you which we will discuss in another post. If the score is ❤ AND your gut feeling tells you that the probability is low you can move onto the next scoring method.

PERC Rule (Pulmonary Rule Out Criteria) PERC Rule Calculator
Age < 50 years
Pulse < 100 bpm
SaO2 > 94%
No unilateral leg swelling
No hemoptysis
No recent trauma or surgery
No prior PE or DVT
No hormone use

If you assess your patient to have NONE of the above than you have essentially ruled out PE. A menumonic that I was taught in the past to remember this is HAD CLOTS: Hormone, Age >50, DVT/PE history, Coughing blood, Leg swelling, O2 >95%, Tachycardia 100+, Surgery/trauma <28 d.

Keeping this stuff in mind will help you manage your patient better and recognize treatment modalities and transport considerations.