The Challenge of Chest Pain Assessment
Chest pain is one of the most common chief complaints in EMS, accounting for approximately 10% of all 911 calls. While acute coronary syndrome (ACS) is the most dangerous cause, chest pain can originate from cardiac, pulmonary, gastrointestinal, musculoskeletal, and psychological sources. Your job as an EMT is not to make a definitive diagnosis but to identify potentially life-threatening causes, initiate appropriate treatment, and transport to definitive care.
The OPQRST mnemonic provides a systematic framework for evaluating chest pain: Onset (what were you doing when it started?), Provocation/Palliation (what makes it better or worse?), Quality (what does it feel like?), Region/Radiation (where exactly and does it go anywhere?), Severity (on a scale of 0 to 10), and Time (when did it start and is it constant or intermittent?).
Cardiac Causes of Chest Pain
Acute coronary syndrome encompasses unstable angina, NSTEMI, and STEMI. Classic ACS presents with substernal chest pressure or squeezing that may radiate to the left arm, jaw, or back. It is often accompanied by diaphoresis, nausea, and shortness of breath. However, many patients (especially women, diabetics, and elderly patients) present atypically with isolated jaw pain, epigastric discomfort, fatigue, or shortness of breath without chest pain at all.
Other cardiac causes include pericarditis (sharp chest pain that worsens with deep breathing and improves when leaning forward), aortic dissection (sudden, severe "tearing" pain radiating to the back, often with unequal blood pressures in the arms), and heart failure exacerbation (dyspnea, orthopnea, peripheral edema, crackles in the lungs).
Non-Cardiac Causes
Pulmonary causes include pulmonary embolism (sudden dyspnea and pleuritic chest pain, often with tachycardia and a recent history of immobility or surgery), pneumothorax (sudden sharp chest pain with dyspnea, decreased breath sounds on the affected side), and pneumonia (productive cough, fever, pleuritic chest pain). Gastrointestinal causes include gastroesophageal reflux (burning substernal pain that may mimic ACS) and esophageal rupture (severe chest pain after vomiting). Musculoskeletal causes include costochondritis (reproducible pain with palpation of the chest wall) and rib fractures from trauma.
Field Management Priorities
Regardless of the suspected cause, all chest pain patients deserve a thorough assessment, oxygen if hypoxic, and transport. Assist with prescribed nitroglycerin per protocol (confirm systolic blood pressure above 100 first). Administer aspirin (160 to 325 mg) if ACS is suspected and the patient has no contraindications. Position the patient comfortably, usually semi-Fowler's (sitting up at 45 degrees). Obtain a 12-lead ECG if your scope of practice and equipment allow. Notify the receiving hospital early for any patient with suspected ACS so they can activate the cardiac catheterization lab if needed.