Module 4: Physiology of the Respiratory System - Airflow Obstruction: Evaluation of Reversibility.

Airflow Obstruction: Evaluation of Reversibility

Airflow obstruction is evaluated by spirometry as being either reversible or not reversible.

Definition:

Beta-2 agonists are the screening test for reversibility: for example, 400 micrograms salbutamol administered by MDI.

     



The figure on the left illustrates the change that may be observed on a F/V curve before and after bronchodilator.

Administration of reversibility using bronchodilator by MDI is specific but not very sensitive.

Larger dose of agents (for example, beta-2 agonist +/- anticholinergic by nebuliser) may be used; or a course of oral steroids.

Creative Commons License
Postgraduate Diploma in Occupational Health (DOH) - Modules 3 – 5: Occupational Medicine & Toxicology by Prof Rodney Ehrlich & Prof Mohamed Jeebhay is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License.
Permissions beyond the scope of this license may be available at http://www.healthedu.uct.ac.za/