Chest Pain
Perspective
Approximately 6 million patients visit the emergency department (ED) each year with complaints of chest pain, constituting 9% of all patients seen in EDs in the United States.1 Over the last 10 years, the total number of ED patients with noninjury complaints increased by 22%, whereas the percentage of patients with chest pain decreased slightly.2 Chest pain is a symptom caused by several life-threatening diseases and has a broad differential diagnosis. It is complicated by a frequent disassociation between intensity of symptoms and signs and seriousness of underlying pathology.
Diagnostic Approach
Because of the indistinct nature of visceral pain, the differential diagnosis of chest pain is broad and includes many of the most critical diagnoses in medicine and many nonemergent conditions (Table 26-1).
Rapid Stabilization and Assessment
In clinical evaluation of the patient, the initial questions are “Should I intervene immediately?” and “What are the life-threatening possibilities in this patient?” The answers are usually apparent within the first few minutes after assessment of the patient’s appearance, ECG, and vital signs. If a patient has unilateral chest pain, respiratory distress, shock, and unilateral reduction or absence of breath sounds, immediate intervention with needle or tube thoracostomy is required. In addition, patients with severe derangements in vital signs require stabilizing treatment during a search for the precipitating cause. Patients with respiratory distress require immediate intervention and lead the emergency physician to consider a more serious cause of the pain (Fig. 26-1; also see Chapter 25).
Symptomatic derangements in vital signs are addressed. If vital signs are stable, a focused history and physical examination are performed. Most patients also require a chest radiograph to evaluate the chest pain. If myocardial ischemia is suspected, aspirin and nitroglycerin may be appropriate. Patients with pain and findings suggestive of aortic dissection and with significant hypertension are candidates for immediate reduction of blood pressure (see Chapter 85). Patients with low voltage on the ECG, diffuse ST segment elevation, elevated jugular venous pressure on examination,3 and signs of shock should undergo prompt bedside cardiac ultrasound.
Pivotal Findings
History
1. The patient is asked to describe the character of the pain or discomfort. Descriptions such as “squeezing,” “crushing,” or “pressure” lead the emergency physician to suspect a cardiac ischemic syndrome, although cardiac ischemia can also be characterized by nonspecific discomfort, such as “bloating” or “indigestion.” “Tearing” pain that may migrate from the front to back or back to front is the classic description in aortic dissection. “Sharp” or “stabbing” pain is seen more in pulmonary and musculoskeletal diagnoses. Patients reporting a “burning” or “indigestion” type of pain may initially be thought to have a gastrointestinal condition, but owing to the visceral nature of chest pain, patients with all causes of pain may use any of the preceding descriptions. Of note, descriptors may vary among ethnic groups, and, for example, “sharp” may mean “severe.”
2. Additional history about the patient’s activity at the onset of pain may be helpful. Pain occurring during exertion suggests an ischemic coronary syndrome, whereas progressive onset of pain at rest suggests acute MI. Pain of sudden onset is more typical with aortic dissection, PE, or pneumothorax. Pain after meals is more indicative of a gastrointestinal cause.
3. The severity of pain is commonly quantified with a 1-to-10 pain scale. Alterations in pain severity are documented at times of onset, peak, present, and after intervention.
4. The location of the discomfort is described. Pain that is localized to a small area is more likely to be somatic versus visceral in origin. Pain localized at the periphery of the chest is more likely to have a pulmonary rather than a cardiac cause. Lower chest or upper abdominal pain may be of cardiac or gastrointestinal origin.
5. Any description of radiation of pain should be noted. Transthoracic pain through to the back should suggest aortic dissection or gastrointestinal causes, especially pancreatitis or posterior ulcer. Inferoposterior myocardial ischemia may also manifest primarily as thoracic back pain. Radiation to the arms, neck, or jaw increases the likelihood of cardiac ischemia.4,5 Pain located primarily in the back, especially interscapular back pain that migrates to the base of the neck, suggests aortic dissection.6
6. Duration of pain is another important historical factor. Pain that lasts a few seconds or minutes is rarely of cardiac origin.7 Pain that is exertional but abates with a few minutes of rest may be a manifestation of cardiac ischemia.4 Pain that is maximal at onset may be caused by aortic dissection.6 Pain that is not severe and persists over the course of days is less likely to be of serious origin than pain that is severe or has a stuttering or fluctuating course.
7. The clinician should consider aggravating or alleviating factors. Pain that worsens with exertion and improves with rest is more likely related to coronary ischemia.4 Pain related to meals is more suggestive of a gastrointestinal cause. Pain that worsens with respiration is seen more often with pulmonary, pericardial, and musculoskeletal causes.
8. Other associated symptoms may suggest the visceral nature of the pain (Table 26-2). Diaphoresis should lead to an increased clinical suspicion for a serious or visceral cause. Hemoptysis, a classic PE sign, is rarely seen.8 Near-syncope and syncope lead to higher likelihood of a cardiovascular cause or PE. Dyspnea is seen in cardiovascular and pulmonary disease. Nausea and vomiting may be seen in cardiovascular and gastrointestinal complaints.
