Indications for administering bronchodilator drugs
If there is evidence of airway obstruction, whatever the severity, assessment of bronchodilator responsiveness is indicated. This is because it is important to establish the patient′s personal best spirometric values. Even though this provides only information at a given point in time, it is clinically relevant to establish whether the airway obstruction is partially or completely reversible. In the case of partially reversible airway obstruction it may be desirable to administer corticosteroids to address an inflammatory component. It should be kept in mind that reversibility of airway obstruction may vary considerably in time, reflecting variations in the severity of disease and the extent to which the patient is exposed to bronchoconstricting stimuli at a particular moment (consult ref. 1-2 about variability in bronchodilator responsiveness within subjects).
Bronchodilator responsiveness is almost invariably assessed after administration of a short- and quick-acting bronchodilator drug. Functional antagonists (such as β2-sympathomimetics) are to be preferred over receptor antagonists (such as anticholinergics or anti-leukotrienes). In view of the relatively favorable therapeutic effectiveness in COPD, anticholinergics are also frequently used in spirometric tests of lung function.
The lack of a response to bronchodilator testing in a laboratory does not preclude a clinical response to bronchodilator therapy.
- Kerstjens HAM, Brand PLP, Quanjer PhH, van der Bruggen-Bogaerts BAHA, Koëter GH, Postma DS, and the Dutch CNSLD Study Group. Variability of bronchodilator response and effects of inhaled corticosteroid treatment in obstructive airways disease. Thorax 1993; 48: 722-729.
- Calverley PMA, Burge PS, Spence S, Anderson JA, Jones PW, for the ISOLDE Study Investigators. Bronchodilator reversibility testing in chronic obstructive pulmonary disease. Thorax 2003; 58: 659-664.
- List of references.