Total Body Plethysmography

Aetna covers total body plethysmography as medically necessary only as an adjunct to complete pulmonary function testing (including residual volumes and diffusion) for: determination of bronchial hyperreactivity (methacholine, histamine, or isocapnic hyperventilation); assessment of bronchodilator response when clinical improvement occurs but FEV1 does not improve on spirometry; evaluation of obstructive lung disease (e.g., bullous emphysema, cystic fibrosis) when helium dilution/nitrogen washout give artifactually low volumes; and measurement of airflow resistance when plethysmography is required to calculate true lung volumes. It is considered experimental/investigational and not covered for all other indications (e.g., early COPD detection, pectus excavatum, primary pulmonary hypertension, and bleomycin therapy monitoring) because effectiveness has not been established.

"Aetna considers total body plethysmography medically necessary as an adjunct to complete pulmonary function testing (including residual volumes and diffusion) for any of the following indications:"