The Difficult Asthmatic

Summary

The most common reason why asthma presents difficulties in management is the failure to treat it with drugs which are appropriate and taken in adequate dosage. An understanding of the pathophysiology and aetiology of asthma is essential if full advantage is to be taken of the wide range of drugs now available for treating it. Airflow obstruction due to bronchial muscle constriction is usually readily reversible by bronchodilators, whereas that due to the inflammatory component of asthma is refractory to the latter and can only be reversed by steroids. Refractory airflow obstruction is liable to be confused with irreversible obstruction which occurs in those patients whose asthma is complicated by chronic obstructive bronchitis or other lung disease.

The choice between symptomatic, preventive and suppressive forms of treatment should be made only after a careful assessment has been carried out with objective measurement of airflow obstruction. The Wright peak flow meter is unsurpassed for this purpose. By its means it should be possible to estimate how much of a patient’s airflow obstruction is readily reversible, how much is refractory and how much is irreversible.

In general, the aim of treatment is to relieve airflow obstruction rather than to counteract supposed aetiological factors. Both doctor and patient must understand the purpose, limitations and possible dangers of any drug which is prescribed. Steroids are the only form of treatment which is effective in persistent refractory asthma. Prejudice against steroids has resulted in many patients being deprived of their benefit, but this situation may change with the recent introduction of steroid aerosols.