Causes and Clinical Presentation

Most patients will have a single cause for their cough; however, in some patients, two or three simultaneous causes (comorbidities) may be present. Cough may be acute (sudden onset, usually severe with a short course, self-limited), chronic (persistent and troublesome for more than 3 weeks), or paroxysmal (periodic, prolonged, and forceful episodes). An acute self-limited cough is usually due to a viral infection involving the upper airway, which usually resolves in a few days. A chronic persistent cough is most commonly caused by postnasal drip syndrome, followed by acute asthma, acute exacerbation of chronic obstructive pulmonary disease (COPD), allergic rhinitis, gastroesophageal reflux disease (GERD), chronic bronchitis, bronchiectasis, and other conditions such as left heart failure, bronchogenic cancer, and sarcoidosis. In smokers, chronic cough is usually due to chronic bronchitis (“smoker’s cough”). Still other chronic coughs may result from certain medications, such as angiotensin-converting enzyme (ACE) inhibitors commonly prescribed for congestive heart failure and other cardiac conditions. Though not fully understood, patients taking ACE inhibitors may develop a chronic dry cough, possibly as a result of an increase in cough mediators that accumulate in the upper airway. Hence, the medication history described in Chapter 2 can provide vital clues to the underlying cause. Aggravating, painful, or persistent cough or cough equivalent, such as throat clearing, is not normal and warrants further clinical investigation.

Cough may occur in conjunction with other pulmonary symptoms such as wheezing, stridor, chest pain, and dyspnea. In addition, cough may cause problems. The vigorous muscular activity and high intrathoracic pressures created by forceful coughing may produce a number of complications, such as torn chest muscles, rib fractures, disruption of surgical wounds, pneumothorax or pneumomediastinum, syncope (fainting), arrhythmia, esophageal rupture, and urinary incontinence.

Descriptions

Cough should be described as effective (strong enough to clear the airway) or inadequate (audible but too weak to mobilize the secretions), productive (mucus or other material is expelled by the cough), or dry and nonproductive (moisture or secretions are not produced). Because dry coughs often become productive, a chronologic report of the circumstances surrounding the change and a description of the sputum should be recorded.

The quality, time, and setting in which a cough occurs may also provide some clues to the location and type of disorder (Table 3-2). Barking (like a seal), brassy (harsh, dry), and hoarse coughs, as well as those associated with inspiratory stridor, are usually heard when there is a problem with the larynx (e.g., infection or tumor). Wheezy coughs (accompanied by whistling or sighing sounds) suggest bronchial disorders. Acute, productive coughs are most often seen with allergic asthma as well as bacterial or viral respiratory infections, and chronic productive coughs are generally indicative of significant bronchopulmonary disease (e.g., chronic bronchitis). Hacking (frequent brief periods of coughing or clearing the throat) may be dry and the result of smoking, a viral infection, a nervous habit, or difficult-to-move secretions, which may occur with postnasal drip.

Acute onset or change in a cough is obvious to the patient and family and probably to the interviewer; therefore, an accurate history is very important and easily obtained. However, careful inquiry is often required to identify the characteristics of a chronic cough. Because coughing and sputum production are generally not socially acceptable, patients may deny or minimize the presence of the cough or learn to adapt to the extent that they may even be unaware of coughing chronically. Questioning family members or close friends may provide valuable information about the presence and characteristics of a cough.

Causes and Descriptions

Excessive sputum production is most often caused by inflammation of the mucous glands that line the tracheobronchial tree. Inflammation of these glands occurs most often with infection, cigarette smoking, and allergies.

Sputum should be described as to the color, consistency, odor, quantity, time of day, and presence of blood or other distinguishing matter. The amount may vary from scanty (a few teaspoons) to copious (as much as a pint or more), as seen in certain chronic bronchial infections and bronchiectasis. These characteristics of the sputum may be highly indicative of the underlying disorder (Table 3-3). Though sputum culture and sensitivity tests described in Chapter 7 provide for a more in depth microbiologic examination of sputum, bedside examination can be helpful as an initial screening tool.

The consistency of sputum may be described as thin, thick, viscous (gelatinous), tenacious (extremely sticky), or frothy. Color depends on the origin and cause of the sputum production. Descriptions for the color of sputum include mucoid (clear, thin, and may be somewhat viscid as a result of oversecretion of bronchial mucus), mucopurulent (thick, viscous, colored, and often in globs with an offensive odor), and blood-tinged. Copious, foul-smelling (fetid) sputum that separates into layers when standing occurs with bronchiectasis and lung abscess when the patient’s position is changed.

Morning expectoration implies accumulation of secretions during the night and is commonly seen with bronchitis. Nonpurulent, silicone-like bronchial casts are seen with asthma. Sudden large amounts of sputum production may be indicative of a bronchopleural fistula.

Causes

Differential diagnosis is complex and includes bronchopulmonary, cardiovascular, hematologic, and other systemic disorders (Box 3-1). A history of pulmonary or cardiovascular disease; cigarette smoking and tobacco use; trauma; aspiration of a foreign body; repeated and severe lung infections; bleeding disorder; use of anticoagulant agents (warfarin or heparin), aspirin, nonsteroidal anti-inflammatory agents, or chemotherapeutic agents; or inhaling crack cocaine suggests the possible cause of hemoptysis. A history of travel to places where tuberculosis or fungal infections, such as coccidioidomycosis or histoplasmosis, are prevalent, including central Africa (tuberculosis) and the San Joaquin Valley of California (coccidioidomycosis), may also help identify the underlying disorder.

The site of bleeding may be anywhere in the respiratory tract, including the nose or mouth. The amount and mechanisms of bleeding are varied. Tissues engorged by inflammation or backpressure from heart failure or other cardiac problems may bleed easily and cause frothy pink sputum. Trauma bruises tissue or may tear a vessel. Chronic or repeated respiratory infections resulting in bronchiectasis can predispose the patient to bleeding. A tumor or granuloma can erode surrounding tissue or the bronchial wall. An acute infective process can create an abscess in the bronchial tree or lung parenchyma, which can erode into another structure (e.g., bronchopleural fistula) or completely through a vessel wall. If the vessel is an artery, hemorrhage can be sudden and massive and may lead to death due to excessive blood loss.

Historically, tuberculosis and bronchiectasis were the most common causes of hemoptysis. Erosive bronchitis in smokers with chronic bronchitis and bronchogenic carcinoma are now also recognized as frequent causes of hemoptysis. In fact, blood-streaked sputum may be the only hint that bronchogenic cancer has developed in the smoker.

Descriptions

Obtaining a description of the amount, odor, color, and appearance of blood produced, as well as the acuteness or chronicity of the bleeding, may provide a clue to the source of bleeding. The most common causes of streaky hemoptysis are pulmonary infection (chronic bronchitis, bronchiectasis, or bacterial pneumonias), lung cancer, and thromboemboli. Small stones or gravel mixed with the sputum and blood suggests broncholithiasis.

Careful evaluation and description of hemoptysis is crucial because it can include clots of blood as well as blood-tinged sputum. Coughing up clots of blood is a symptom of extreme importance suggesting serious illness. Massive hemoptysis (400 mL in 3 hours or more than 600 mL in 24 hours) is seen with lung cancers, tuberculosis, bronchiectasis, and trauma. It is an emergency condition associated with possible mortality. Immediate action is required to maintain an adequate airway, and emergency bronchoscopy and surgery may be necessary.

Associated symptoms may also provide a clue to the source of bleeding. Sometimes patients can describe a sensation, often warmth, in the area where the blood originates. Others perceive a bubbling sensation in the tracheobronchial tree followed by expectoration of blood. Hemoptysis associated with sudden onset of chest pain and dyspnea in a patient at risk for venous stasis of the legs must prompt evaluation for pulmonary embolism and possible infarction. Frothy, blood-tinged sputum associated with paroxysmal cough accompanies cardiac-induced pulmonary edema.

Hemoptysis without severe coughing suggests a cavitary lesion in the lung or bronchial tumor.

Hemoptysis versus Hematemesis

“Spitting up blood,” as patients frequently call it, may be confused with blood originating in the oropharynx, esophagus, or stomach. The patient with a nosebleed at night could cough up blood in the morning. The presence of symptoms, such as nausea and vomiting, especially with a history of alcoholism or cirrhosis of the liver, may suggest the esophagus or stomach as the source. Conversely, vomiting of blood may sometimes manifest from bronchopulmonary bleeding. When bleeding occurs during the night and the blood reaches the oropharynx, it may be swallowed without the patient waking. The swallowed blood may act as an irritant, and the patient may vomit early in the morning. Careful questioning and often examination of the bloody sputum are required to distinguish hemoptysis from hematemesis (vomited blood) (Table 3-4). It is important to obtain a detailed sequence of events to determine whether the blood originated in the respiratory tract and was swallowed and then vomited, or the blood was vomited, aspirated, and later expectorated.

Subjectiveness of Dyspnea

Dyspnea may be difficult to evaluate because it is so subjective. The sensation of dyspnea is made up of the following components:

A patient’s perception of dyspnea may have no relation to the patient’s breathing appearance. Remember, dyspnea is subjective—a symptom—and what the patient feels. A patient may have labored and rapid breathing and deny feeling short of breath. Conversely, a patient may appear to be breathing comfortably and slowly but may feel breathless. You can never assume that a patient with a rapid respiratory rate is dyspneic. In addition, a patient’s complaint of dyspnea must be considered a symptom of a medical problem and must be taken seriously until proved otherwise. In fact, the onset of dyspnea may be the first clue to identifying serious problems.

Patients’ perceptions of dyspnea vary greatly. A healthy person notices the increased ventilatory demand required to climb stairs or to exercise but expects it and does not interpret it as unpleasant. In fact, the athlete may consider the breathlessness occurring after a sprint to be exhilarating and even a necessary aspect of physical conditioning. Patients, on the other hand, may describe the feeling as “breathless,” “short winded,” “feeling of suffocation,” or a sensation of “air hunger” at rest or during minimal exercise.

Dyspnea Scoring Systems

A variety of methods have been devised to help quantify dyspnea at a single point in time or to help track changes in dyspnea over time or with treatment. In the clinical setting, patients are frequently asked to rate the severity of a symptom, such as dyspnea or pain, using a severity scale of 0 to 10. The patient is asked a question such as “On a scale of 0 to 10, how would you rate your shortness of breath when you are resting? Using this scale, 0 means no shortness of breath, and 10 means the worst or maximum shortness of breath.” The patient’s response may be recorded simply as “SOB at rest 7/10.”

Visual analog scales are straight lines, usually 10 cm long, with the words “Not Breathless” at one end and “Extremely Breathless” at the other end. The patient marks the line to indicate his or her level of respiratory discomfort. The score is measured as the length of the line between “Not Breathless” and the mark made by the patient. The score may be recorded as 5.5/10 or simply as 5.5 (the 10 is implied).

A Modified Borg Scale, such as shown in Table 3-5, also uses a 0 to 10 scoring system with descriptive terms to depict the perceived intensity of a symptom such as dyspnea after a specified task. Tools like the frequently used American Thoracic Society Shortness of Breath Scale (Table 3-6) specify the degree of dyspnea (slight, moderate, severe, or very severe) using descriptive terms as well as a numerical grading system. In addition, there are also questionnaires that attempt to quantify the severity of dyspnea by asking patients to rate their shortness of breath while performing a variety of activities of daily living.

More recently, other scales have emerged for rating dyspnea in cardiopulmonary disease. One such scale is the Dyspnea-12 Survey, or “D-12,” which quantifies a patient’s level of breathlessness using 12 physical and psychosocial descriptors. This rating scale is showing particular promise in determining the severity of dyspnea in patients who have asthma.

Causes, Types, and Clinical Presentation of Dyspnea

Dyspnea is most often related to pulmonary or cardiac disease, but it is also seen with hematologic, metabolic, chemical, neurologic, psychogenic, and mechanical disorders. Dyspnea may be described by clinical type as shown in Table 3-7, or the causes of dyspnea may be grouped by body system as listed in Table 3-8.