Our discussion assumes there are NO signs of life-threatening lack of oxygen.
Anyone who says they’ve recently begun to feel “SOB” may not be allowed inside a building without a Covid Test. But some patients need to be seen no matter what; every office or clinic should have its own mechanism, maybe in a designated exam room, maybe calling an ambulance.
Causes of Acute (Recent-Onset) Shortness of Breath (SOB)
|xxxHEART & CIRCULATION |
• Myocardial Infarction (M.I.) xxx (heart attack)
• Angina (coronary artery xxxdisease)
• Heart Failure (HF)
• Early Shock (e.g. Sepsis)
• Pulmonary Embolism (PE)
• Bronchospasm (from Viral xxInfection, Asthma, or COPD)
• Uncommon Lung Conditions
• Anaphylaxis (allergy)
• Obstruction in Upper Airway
• Rare Causes
Here’s how we approach the patient with Acute SOB which doesn’t appear imminently life-threatening (after establishing it’s what I call “True” SOB (always feels worse with exertion) See the link for an explanation.
- Risks: M >40, F >45; smoker; hypertension; diabetes; family history; high cholesterol
- Other Symptoms at time of SOB: chest pain, nausea; cold sweat; lightheaded
- Call 911 if thinking M.I. or progressive unstable Angina (& give an aspirin) (see Diagnosing Coronary Artery Disease for what they do in ER)
- Obtain EKG. If thinking stable Angina, order stress tests (see Diagnosing Coronary Artery Disease)
- May give intensive medical treatment while awaiting stress test results
2. Think about a Pulmonary Embolism (PE):
- Inquire about both: 1) very sudden onset of SOB; and 2) risk factors for PE:
- Send to ER if suspicious, for d-Dimer blood test: if high → special CT Scan.
3. Look for evidence of Heart Failure (especially among older persons)
- Can’t sleep lying flat, wake up gasping for breath, swollen feet, weight increase, rales in both lungs (heard by stethoscope), certain findings on heart exam
- Manage in ER if very recent onset (i.e. unstable)
- If stable: Order certain labs (blood count, kidney tests, liver tests, BNP)
- Order an EKG & esp. an echocardiogram
- Maybe start treatment pending results
- If diagnose “Heart Failure,” must seek a cause (always ask, “Why?”)
4. Consider Pneumonia: fever, cough, maybe a patch of rales on lung exam.
- Get a Chest X-Ray
5. Don’t Forget other potentially serious conditions if symptoms began within 1-2 days:
- Uncommon Upper Airway Disease (stridor heard by stethoscope) → best managed in ER
- Sepsis (there’s almost always fever) → fever + change in vital signs lying to standing → to ER
- Acute Anemia → Obtain CBC; if also change in vital signs lying to standing → to ER
- Especially don’t forget rare Anaphylaxis
- wheezing or stridor (lung sounds), with specific criteria including hives, swollen lips / face / throat, itching, classic exposure, vomiting/abdominal pain, rapid heart rate, low blood pressure.
- Needs epinephrine stat (= ASAP)
6. Repeat the test for Covid-19 in 2-3 days, especially if other symptoms (fever, body aches, cough, loss of smell). Isolate in the meantime.
- Patient doesn’t have a fever (or if fever, doesn’t seem like pneumonia)
- We hear wheezes or rhonchi with our stethoscope; AND / OR
- There’s a long expiratory phase when listening with stethoscope
- There’s some sort of cough.
BUT, for a patient with recent-onset True SOB who clinically does NOT convincingly seem to have bronchospasm (no cough, normal lung exam), at a minimum we should order:
- Complete Blood Count (for Anemia, infection) and Chest X-Ray (CXR). The CXR will easily identify a number of items on the list of “Rare Causes.” See link for consideration of other possibilities
- For mainly older patients, a BNP (blood test) to rule out Heart Failure
- Other basic lab tests for the variety of causes
- EKG, only helpful if abnormal (EKG can be normal with heart attack & anything else)
- Other work-up (echocardiograms, pulmonary function tests, etc.) discussed under our topic Chronic SOB, but may obtain sooner if patient’s SOB appears bad.
See also Acute Shortness of Breath — Full Text for more in-depth explanations and discussions.