Shortness of Breath in the ER and What Doctors Are Really Looking For
How We Separate a Tight Airway From a Failing Heart in Minutes
Chief Complaint Why This Symptom Gets Fast Attention
Shortness of breath is one of the most common reasons people come to the ER. It is also one of the most urgent. When someone says, “I cannot breathe,” we do not casually place them in a long line. We move.
A chief complaint is the main symptom that brought you in. Not the whole story. Not every worry. The headline. Shortness of breath is a headline that can represent dozens of problems. Some are annoying. Some are lethal. Our job is to sort that quickly.
First Look Is This Dangerous Right Now?
Some patients arrive wheezing. Tight lungs. Struggling to speak in full sentences. Others look quiet, almost too quiet, with lips turning blue. Blue discoloration is called cyanosis and it often means oxygen levels are dangerously low.
We start with vital signs, oxygen saturation, and general appearance. We listen to the lungs. Wheezing suggests narrowed airways, common in asthma and COPD. Crackles can suggest fluid or infection. A single sided absence of breath sounds raises concern for pneumothorax, a collapsed lung.
The first question is not “what is it.” The first question is “how unstable is it.”
The Big Dangerous Causes We Cannot Miss
Shortness of breath is often lung related, but not always. The high risk diagnoses we think about early include pulmonary embolism, which is a blood clot in the lungs, pneumonia, which is infection filling the air sacs, heart failure, which is fluid backing up into the lungs, and heart attack, which can cause breathlessness even without classic chest pain.
We also consider pneumothorax, where air escapes the lung and compresses it, and severe allergic reaction, called anaphylaxis, where airway swelling and bronchospasm can rapidly worsen breathing. Sepsis, a systemic response to infection, can present with fast breathing because the body is under metabolic stress. Shortness of breath can be the symptom of the lungs, the heart, the blood, or the whole body.
Sometimes It Is Not the Lungs at All
Anemia can cause shortness of breath even if the lungs are perfectly fine. Hemoglobin is the protein in red blood cells that carries oxygen. If hemoglobin is low, oxygen delivery drops. Patients often feel winded with exertion. They may look pale. They may have fatigue more than cough.
Metabolic problems can also drive breathing changes. Severe acidosis, meaning the blood is too acidic, makes people breathe fast as the body tries to blow off carbon dioxide. This is often seen in diabetic ketoacidosis. That pattern can look like panic or asthma to the untrained eye. It is not. The symptom is breathing. The problem may be oxygen delivery, acid base balance, or circulation.
The Workup Is Structured, Not Random
Most patients will get a chest X ray early. It can identify pneumonia, heart failure patterns, pneumothorax, and pleural effusion, which is fluid collecting outside the lung. Bloodwork often includes a complete blood count to check white blood cells and hemoglobin, a metabolic panel, and sometimes BNP, a marker of heart strain, or troponin if cardiac causes are possible.
If pulmonary embolism is a concern, we may use decision tools such as PERC or Wells criteria to estimate risk. In low risk patients, a D dimer can help rule out clots. In higher risk cases, CT pulmonary angiography may be needed. CT carries radiation and contrast risk, so we do not order it casually. We test with intent. Not because we like tests. Because shortness of breath has too many dangerous possibilities to guess.
Treatment Depends on the Cause
If this is asthma or COPD, we treat bronchospasm, which is tightening of the airway muscles. Nebulizer treatments, often albuterol and ipratropium, open the airways. Steroids reduce inflammation but take time. Oxygen supports the body while the lungs recover. In severe cases, noninvasive ventilation such as BiPAP can reduce work of breathing.
If this is pneumonia, antibiotics may be needed. If this is heart failure, diuretics remove excess fluid. If this is pulmonary embolism, anticoagulation is started. If this is anaphylaxis, epinephrine is the key medication, not the optional one.
Shortness of breath is not a diagnosis. It is a clue. Treatment is only as good as the underlying diagnosis.
THE BOTTOM LINE
• Shortness of breath is a common chief complaint that can signal lung disease, heart disease, anemia, or systemic illness
• The ER approach focuses first on stability, then on ruling out dangerous causes like pulmonary embolism, pneumonia, heart failure, and pneumothorax
• Testing and treatment are targeted to the suspected cause, with oxygen and airway support used as needed
Written by a Board-Certified Emergency Medicine Physician