FVC - forced expiratory vital capacity
The volume change of the lung between a full inspiration to total lung capacity and a maximal expiration to residual volume. The measurement is performed during forceful exhalation; the preceding maximal inhalation need not be performed forcefully . The volume assessed is the forced expiratory vital capacity (FEVC), commonly called forced vital capacity (FVC). The maneuver is almost invariably performed in conjunction with the assessment of the FEV1 and of maximum expiratory flow-volume curves. In patients with obstructive lung disease FVC < EVC < IVC.
report the largest value of three technically satisfactory maneuvers.
the FVC reported should not differ by more than 150 mL from the next largest FVC, or 100 mL if the FVC is 1.0 L or less (procedures, ref. 3). If the difference is larger up to 8 maneuvers (ref. 1) should be performed.
if more than 8 maneuvers are required to satisfy the criteria, then report the largest FVC with a note that reproducible measurements could not be obtained.
Ref. 1 - If 8 maneuvers have not led to a FVC or FEV1 meeting the above requirements for reproducibility, then further attempts are useless:
Ferris BG Jr, Speizer FE, Bishop Y, Prang G, Weener J.
Spirometry for an epidemiologic study: deriving optimum summary statistics for each subject. Bull Europ Physiopathol Respir 1978; 14: 145-166.
Kanner RE, Schenker MB, Munoz A, Speizer FE. Spirometry in children: methodology for obtaining optimal results for clinical and epidemiological studies. Am Rev Respir Dis 1983; 127: 720-724.
Quanjer PhH, Tammeling GJ, Cotes JE, Pedersen OF, Peslin R, Yernault JC. Lung volumes and forced ventilatory flows. Official Statement of the European Respiratory Society. Eur Respir J 1993; 6 suppl. 16: 5-40. Erratum Eur Respir J 1995; 8: 1629.
American Thoracic Society. Standardization of spirometry: 1994 update. Am J Respir Crit Care Med 1995; 152: 1107-1136.
Miller MR et al. Standardisation of spirometry. ATS/ERS task force: standardisation of lung function testing. Eur Respir J 2005; 26: 319-338.