CanadiEM Frontline Primer

CanadiEM Frontline Primer – Dyspnea or Shortness of Breath

In Medical Concepts by Afsheen MeharLeave a Comment

Can’t Miss Diagnoses

  • COVID-19 or other Viral Illnesses (Obviously)
  • Anaphylaxis
  • Pneumonia (PNA)
  • Congestive Heart Failure (CHF)
  • Acute Coronary Syndrome (ACS)
  • Acute exacerbation of Asthma
  • Acute Exacerbation of Chronic Obstructive Pulmonary Disease (COPD)
  • Pulmonary Embolism (PE)
  • Aortic Dissection
  • Pneumothorax (PTx)
  • Cardiac Tamponade
Mimics due to high respiratory rate
  • Diabetic Ketoacidosis
  • Sepsis

Points to focus upon

  • Previous Seasonality / Patterns – to differentiate asthma from COVID-19, etc.
  • Allergies or new allergic reaction precipitants (soaps, perfumes)
  • Medication history and adherence; inhalers, diuretics
  • Pulmonary Embolism risk factors (use PERC and Wells Criteria)
  • CAD risk factors (also compare new and old ECGs)
  • Has the patient used their multidose inhaler (MDI) with SPACER? (This is a common reason for Salbutamol “not working”)
  • Functional Status – Exercise Tolerance, Recent Decline?
  • Changes in diet – especially with CHF patients (Higher salt intake?)
  • Use of Medications – Nitro Spray effective? Adherent to anticoagulant prescriptions?
  • Always check for signs of DVT on your physical exam
  • LOOK FOR SIGNS OF ANAPHYLAXIS (swelling, hives, etc.)


  • Chest x-ray
  • CBC, BUN, Cr, Lytes, Glucose, VBG +/- Lactate
  • Serial Troponin where warranted
  • Consider ECG – Remember to compare an old ECG
  • Consider D-Dimer
  • Consider telemetry
Tips on Tests

hs-troponin T – the 2h delta to rule-out is <4ng/L and the delta to rule-in is >= 10ng/L. ( EM CASES)

Remember – don’t be purely fooled by an elevated troponin – COVID-19 is known to cause MYOCARDITIS in patients (which can lead to a troponin elevation), read more here.

CXR – looking for alternative diagnoses (Pneumothorax, pneumonia) or incidental findings (ground-glass opacities, suggestive of COVID-19)



Be careful NOT to fully anchor on the diagnosis of COVID-19 related viral illness, however, remember that early research shows that COVID-19 is probably pro-inflammatory and creates a hyper-coagulable state. VTE may be more prevalent in this population.

Always consider that your patient may have more than one diagnosis too.

Recommended reading, videos, and podcasts

The following is part of the CanadiEM Frontline Primer. An introduction to the primer can be found here. To return to the Primer content overview click here.

This post was edited by Dr. Brent Thoma MD FRCPC. This post was copyedited and uploaded by Evan Formosa.

Afsheen Mehar

Dr. Afsheen Mehar is a resident physician at the University of Toronto in the RCPSC Emergency Medicine Training Program. Her greatest passions are medical education, POCUS and austere medicine. She holds an RDMS certification in ultrasound.

Teresa Chan

Senior Editor at CanadiEM
Emergency Physician. Medical Educator. #FOAMed Supporter, Producer and Researcher. Chief Strategy Officer of CanadiEM. Associate Professor, Division of Emergency Medicine, Department of Medicine, McMaster University.