Abstract
As part of the consensus workshop regarding lung volume measurements for the American Thoracic Society and European Respiratory Society, this background paper reviews mechanisms and risks of cross-infection resultant from performing measurements of absolute lung volumes either by body plethysmography, gas dilution, or gas wash-out techniques. Published reports of infection attributable to the performance of lung volume measurements are extremely rare. Nevertheless, because some infectious agents could be transmitted during measurements of lung volumes, and because of widespread concerns both of patients and some medical personnel about the risks of transmission of infections during inspiration from equipment used by other patients, a variety of measures have been advocated to minimize the risks of cross-infection. Workshop participants were divided in opinion about whether such testing does indeed pose significant risk of cross-infection, and also could not agree regarding optimal measures to prevent cross-infection. Although there is conflicting information regarding the efficacy of particulate filters for protecting cross-contamination of downstream equipment and tubing, the author recommends that such filters be used when making lung volume measurements, but only if the filter has acceptably low resistance (e.g. <0.15 kPa x L(-1) x s (1.5 cmH2O x L(-1) x s)), and the measurements are adjusted for the impact of the added resistance and dead space.
