CHAPTER 7 Chest pain
Clue: A quick diagnosis of acute MI greatly increases the patient’s chances of survival.
Diagnostic reasoning: focused history
The identification of potentially acute life-threatening situations must be made immediately. After you have determined that there is no immediate risk of severe oxygen deprivation to vital organs (e.g., MI, aortic dissection, and PE), proceed with a focused history (Table 7-1).
Table 7-1 Differentiating Ischemic from Nonischemic Chest Pain
| FACTORS | ISCHEMIC ORIGIN | NONISCHEMIC ORIGIN |
|---|---|---|
| Character of pain | Constricting, squeezing, burning, heavy feeling | Dull or sharp pain |
| Location of pain | Substernal, midthoracic; radiates to arms, shoulders, neck, teeth, forearms, fingers; interscapular | Left submammary and hemothorax areas |
| Precipitating factors | With exercise, excitement, stress, after meals | Pain after exercise; provoked by specific body movements or deep breaths |
Modified from Selzer A: Principles and practices of clinical cardiology, ed 2, Philadelphia, 1983, Saunders.
Characteristics of pain
Pneumonia, PE, and pneumothorax present with chest pain. The patient with PE is able to point to the area of pain over the affected lung and usually describes a gripping, stabbing pain that is moderate to severe in intensity. The pain can radiate to the neck or shoulders. Patients experiencing a pneumothorax most frequently report mild to severe chest pain of sudden onset located in the lateral thorax and radiating to the ipsilateral shoulder. The quality of pain is described as sharp or tearing. Chest pain of pneumonia is located over the area of infiltration and does not radiate. It frequently has a burning or stabbing quality and is associated with cough (see Chapter 10).
Remember that chest pain is subjective and that prior experience, personal attitudes, and cultural values form the patient’s perception of pain. The severity of the chest pain is not an indication of the severity of the condition. Assessment of the severity of the pain is often made easier by the use of rating scales that use 1 to 10 or happy to sad faces (see Figure 2-1).
Risk factors
According to the report of the U.S. Preventive Services Task Force, clinically significant coronary artery disease (CAD) is uncommon in men under 40 and premenopausal women, but risk increases with advancing age. The presence of risk factors, such as smoking, hypertension, diabetes, high cholesterol level, obesity, and family history of heart disease increases the risk of CAD. The National Cholesterol Education Program (2001) identifies the following major risk factors for CAD: cigarette smoking, hypertension, low high-density lipoprotein (HDL) cholesterol level (<40 mg/dL), a family history of premature coronary heart disease, and age (men 45 years and older; women 55 years and older). In addition, a lipoprotein panel after fasting should be obtained that includes low-density lipoprotein (LDL) (<100 mg/dL is optimal) and total cholesterol values (<200 mg/dL is desirable).
Location and character of pain
Lung pain is caused by the involvement of adjacent structures. The trachea and large bronchus are innervated by the vagus nerve (cranial nerve X). The finer bronchi and lung parenchyma are free of pain innervation, and therefore extensive disease can occur in the periphery of the lungs without pain until the process extends to the parietal pleura. Pleural pain, or pleuritis, results from the loss of normal lubricating function and irritation of the serous membranes of the pleural surfaces. It is a constant, localized, cutting sensation that is accentuated with respiratory movement. Diaphragmatic pleural pain can be referred to the base of the neck or abdomen. Children often report chest pain from tachyarrhythmia because they are unable to differentiate between true pain and the unusual sensation of the arrhythmia. Cardiac causes of chest pain in children are usually associated with congenital anomalies or acquired diseases of the coronary artery, such as Kawasaki disease.
History of chest trauma
A careful history of preceding activities should be obtained to detect any recent muscle strain. Posttraumatic pericardial effusion can develop 1 to 3 months after chest trauma. Blunt injury can cause hemothorax, pneumothorax, soft tissue injury, and rib fracture. A ruptured spleen can cause irritation of the phrenic nerve, producing shoulder pain.
