Asthma: pathophysiology and clinical correlates.

Sufficient data has now accumulated that demonstrates that a careful analysis of the presenting signs and symptoms of a patient with acute asthma will permit clinically useful conclusions to be drawn regarding the magnitude and severity of the underlying airway obstruction and the expected response to therapy. If a patient with severe obstruction deviates from this expected course, objective measurements of mechanical function and gas exchange should be obtained. In our current state of knowledge, these measurements should then be used as the prime indices of therapeutic effectiveness and less reliance should be placed on traditional clinical approaches.