A 44-year-old man awakens his wife in the middle of the night. She hears, "uuuhhh...uuuhhh...uuuhhh," a terrible gasping sound. This has happened irregularly for the past 5 years. The onset is typically without warning. She reaches for a medication which, when administered, alleviates his symptoms.

A routine checkup by his physician the next day reveals no abnormal findings.

Laboratory studies show: hematocrit 45%, glucose 80 mg/dL, and creatinine 1.1 mg/dL. An arterial blood gas on room air shows: pO₂ 95 mm Hg, pCO₂ 40 mm Hg, pH 7.41, HCO3 27 meq/L, and oxygen saturation 95%.

Questions:

1.1 What physical examination findings are most likely present during one of his episodes? What would a chest roentgenogram show?

Inspiratory wheezes would be auscultated. The patient might appear cyanotic if the episode were severe. The chest roentgenogram might show hyperlucency of lung fields and hyperexpansion.

1.2 What is the most likely diagnosis?

Intrinsic (adult) asthma.

Allergic asthma is often associated with allergic diseases such as rhinitis, urticaria, and eczema, with positive wheal-and-flare skin reactions to intradermal injection of extracts of airborne antigens, with increased levels of IgE in the serum, and/or with a positive response to provocation tests involving the inhalation of a specific antigen.

Some patients with asthma have no history of allergy, with negative skin tests, and with normal serum levels of IgE. These patients have idiosyncratic asthma. Many develop a typical symptom complex on contracting an upper respiratory illness. The initial insult may be little more than a common cold, but after several days the patient begins to develop paroxysms of wheezing and dyspnea that can last for days to months.

Many patients with asthma have a pattern of disease that does not fit into either of the preceding categories, but may have features of each.

In general, asthma that has its onset in early life tends to have a strong allergic component, whereas asthma that develops late tends to be nonallergic or to have a mixed etiology.

The common denominator underlying the asthmatic diathesis is a nonspecific hyperirritability of the tracheobronchial tree. When airway reactivity is high, symptoms are more severe and persistent, and the amount of therapy required to control the patient's complaints is greater. In addition, the magnitude of diurnal fluctuations in lung function is greater, and the patient tends to awaken at night or in the early morning with breathlessness. The most popular hypothesis at present for the pathogenesis of asthma is that it derives from a state of persistent subacute inflammation of the airways.

1.3 What is the medication he was given?

He received a beta2-adrenergic stimulant of short to intermediate duration, by the inhalation route of administration (metered dose inhaler). Albuterol and terbutaline are good examples.

1.4 What long-term medication(s) would be indicated?

Long-acting beta2 stimulants such as salmeterol, or a leukotriene antagonist such as montelukast, may be used if the asthmatic attacks occur frequently. However, in this case the attacks appear infrequently, so just a "rescue" medication for the acute event is indicated. The medication should be close at hand (and not outdated) for these unpredictable onsets.

1.5 What are long-term sequelae of his disease?

None are likely. Asthma is an episodic disease.