Chapter 33. Pulmonary Emergencies

See also Chapter 13.

Essentials of Diagnosis

Asthma

• Cough, wheezing, chest tightness, often worse at night
• Physical examination:Prolonged expiratory phaseor bilateral wheezing, tachypnea, tachycardia, hypoxia
• Reversible with bronchodilators

Chronic Obstructive Pulmonary Disease

• Smoker with chronic productive cough complains of dyspnea
• Increased sputum production, bilateral wheezing, rales, and rhonchi

General Considerations

Obstructive lung disease is classified into two categories: asthma and chronic obstructive pulmonary disease (COPD). Patients with asthma have disease that is episodic and reversible to a significant degree. Between acute attacks these patients may have relatively normal lung function. However, patients who have persistent inflammation may develop over time permanent changes that contribute to a decline in functional capacity. Patients with COPD, have significant fixed airway obstruction that remains at baseline even when the patient's illness is under optimal control. In addition to the concept of reversibility, there are other characteristics that distinguish these two groups. Asthmatic patients tend to be younger and more likely to have allergic triggers and conditions. A family history is common. Patients with COPD usually have a long history of cigarette smoking and more significant permanent lung injury and chest remodeling. Associated right heart failure does not occur in asthma but is common in advanced cases of COPD.

Many conditions commonly associated with asthma and COPD exacerbations are listed in Table 33–1. Some of these conditions are treatable, and the clinician should ask about them specifically while taking the patient's history.

There are two varieties of COPD: chronic bronchitis and emphysema. Chronic bronchitis is characterized by chronic cough and sputum production and is almost invariably associated with prolonged and heavy cigarette smoking. Such patients usually have increased lung volumes and a barrel-shaped chest with increased lung markings on chest X-ray. In advanced cases they may have cyanosis and peripheral edema due to right heart failure. Patients with emphysema on the other hand are typically thin without cyanosis and breathe through pursed lips. Accessory muscle use is more prominent. The chest X-ray usually shows a paucity of lung markings reflecting tissue destruction. Some patients with emphysema have genetic factors (α1-antitrypsin deficiency) as the basis of their illness, but most have a long history of cigarette smoking.

Clinical Findings