ASTHMA

Asthma is a disease of the lungs that involves episodes of coughing, shortness of breath, wheezing, and increased secretions in the bronchi. Generally, most people will know that they are prone to asthma attacks; however, a first-time episode may occur during an allergic reaction, on exertion or exposure to cold, or as a result of emotional stress. In most cases, the mechanism is the same: narrowing and spasm of the small airways, with increased mucus production.

The victim has difficulty breathing and wheezing on exhalation (most common), with inspiration, or both. Coughing is a major feature. The victim may become quite anxious (“air hunger”). Severe cases lead to rapid respiratory deterioration, cyanosis (blue discoloration of the skin), and the use of accessory muscles of respiration (the victim sits upright and attempts to expand the chest wall by contracting neck muscles and using body movements). When the attack is extreme, wheezing may diminish, because the lungs become so “tight” that there is not enough air movement to create the abnormal breath sounds.

PULMONARY EMBOLISM

A pulmonary embolus is a blood clot that has traveled from a vein somewhere in the body to lodge in the circulation of a lung. Such a clot obstructs the flow of blood through a portion of the lung and prevents the normal transfer of oxygen to blood by the affected lung tissue.

The most common sources of the original blood clots are the veins of the pelvis or legs (“thrombophlebitis”: inflammation of the veins with blood clots). Predisposing factors to thrombophlebitis include dehydration, underlying disease of the veins (such as varicose veins), injuries, cancer, medications (such as birth control pills), injury, obesity, and prolonged immobility (see page 291). There are hereditary genetic factors as well, such as the presence of factor V Leiden thrombophilia, which results in a tendency to form clots in small blood vessels.

If a person has blood clots in the leg(s), symptoms may include leg pain, warmth, or swelling. This may be present in the calf or deeper down within the thigh with extension into the pelvis.

Symptoms of pulmonary embolism include sudden sharp chest pain (occasionally worse with deep breathing), cough (occasionally with blood), shortness of breath, increased rate of breathing, light-headedness, and increased or irregular heart rate. The victim may develop a fever. It is often difficult to distinguish pulmonary embolism from pneumonia (see page 48). If the clot is very large, the victim may collapse and die rapidly.

If a person develops symptoms that may represent pulmonary embolism, he should be rushed to medical attention. If oxygen (see page 431) is available, it should be administered by face mask at a flow rate of 10 liters per minute. If the victim can swallow purposefully, administer an aspirin tablet (325 mg) every 24 hours. If a pulmonary embolism is diagnosed, the patient will be treated with a rapid-acting anticoagulant (“blood thinner”), such as heparin or enoxaparin, while being started on a maintenance anticoagulant such as warfarin (Coumadin).

HEART FAILURE (OFTEN CALLED “CONGESTIVE HEART FAILURE”)

Failure of the heart muscle to pump blood effectively may occur suddenly (usually with a large heart attack) or start gradually and worsen with time (after a heart attack; with infections of the heart muscle; from prolonged cocaine, anabolic steroid, or alcohol abuse; from chronic anemia; etc.). The symptoms include shortness of breath (particularly with exertion), swollen feet and ankles (fluid retention), bubbling noises in the lungs (fluid in the lungs), cough, wheezing, and blue skin discoloration (cyanosis) noted under the fingernails, around the lips, and at the earlobes. Frequently, a victim of heart failure cannot lie flat to sleep (because fluid collects in the lungs), so he wakes up at night suddenly short of breath.

If a victim with known heart failure suddenly worsens, or if a previously healthy individual develops signs of heart failure (which may represent a new heart attack), he should be kept sitting up, unless he is more comfortable lying on his back. Administer oxygen (see page 431) by face mask at a flow rate of 10 liters per minute, and immediately carry him to medical attention. If the victim must travel under his own power, all exertion should be kept to a minimum. If the victim is awake and alert, you can administer nitroglycerin 0.4 mg by tablet or spray under the tongue. Don’t use nonsteroidal antiinflammatory drugs (NSAIDs) in persons with heart failure.

If traveling at high altitude, suspect high-altitude pulmonary edema (see page 339).

CHRONIC OBSTRUCTIVE PULMONARY DISEASE

Chronic obstructive pulmonary disease (COPD) refers to a number of diseases suffered by people who have exposed their lungs to long-term insults, particularly cigarette smoke. Chronic bronchitis (infection, inflammation, or bronchospasm—see page 205) or emphysema (scarring that leads to lack of elasticity, overinflation, or lung collapse) are the most common subsets of COPD. People with COPD have poor respiratory reserves, and cannot tolerate strenuous exercise or extremes of environment. A victim of COPD suffers attacks of shortness of breath and coughing similar to asthma, but can get into serious trouble much faster because of underlying debilitation. The earliest signs of respiratory fatigue should be heeded, and evacuation to a restful situation and physician evaluation are high priorities.

With the exception of epinephrine, you may treat a victim of COPD with the same drugs used for the management of asthma. Effective bronchodilator drugs include albuterol, ipratropium, formoterol, salmeterol, and tiotropium. After an exacerbation of COPD, the victim may benefit from a 10-day course of oral prednisone (40 mg per day).

Administration of high-flow oxygen (greater than 1.5 to 2 liters per minute by nasal cannula, or tube) carries a risk, because correction of the low blood oxygen level (hypoxia) in some individuals with COPD will cause them to stop breathing. This is because they have lost sensitivity to high carbon dioxide levels in the blood as a stimulus for breathing (COPD victims always have a relatively high level of carbon dioxide in the blood), and administration of oxygen removes the remaining stimulus (hypoxia) for breathing. Therefore, any person with COPD who is given oxygen should be watched continuously. If his rate of breathing becomes dangerously slow, or he becomes confused or sleepy, the oxygen flow rate should be lessened. Severe COPD can be catastrophic. If necessary, the person may need to have his breathing assisted.

If a person with COPD shows signs of bronchitis (see page 205) or pneumonia (see below), the first-line antibiotic should be trimethoprim-sulfamethoxazole, amoxicillin, doxycycline, tetracycline, azithromycin, clarithromycin, levofloxacin, or sparfloxacin. Second-line antibiotics include ciprofloxacin, cefixime, cefprozil, ofloxacin, and amoxicillin-clavulanate.

PNEUMONIA

Pneumonia is an infection of the lung(s) characterized by combinations of fever, shaking chills (often with chattering teeth), cough, painful and difficult breathing, chest pain, weakness, and the expectoration of discolored (red, green, yellow, brown) phlegm. Pneumonia may evolve from bronchitis (see page 205) or arise independently. In toddlers or young children, rapid breathing, abdominal pain, poor appetite, and vomiting may be the presenting complaints.