Send to

Choose Destination
Respir Physiol Neurobiol. 2012 Jul 31;183(1):15-9. doi: 10.1016/j.resp.2012.05.009. Epub 2012 May 24.

A comparison of single breath and re-breathe diffusing capacity in emphysema patients and controls.

Author information

Department of Medicine, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA.


In emphysema patients, gas dilutional alveolar volume is underestimated by a 10s single breath maneuver at total lung capacity (TLC) compared with re-breathing at functional residual capacity (FRC); corresponding underestimation of single breath diffusing capacity (DLCO) in emphysema has not been demonstrated. The purpose of this study was to quantify the degree to which re-breathe DLCO at FRC (DLCO(RB)) differs from single breath DLCO at TLC (DLCO(SB)) in emphysema. In 37 consecutively recruited patients with moderate to severe emphysema (FEV1/FVC 40%±10% predicted), DLCO(RB) as % predicted of 91 controls without cardiopulmonary disease was 79%±24%, significantly greater than % predicted DLCO(SB) (44%±19%; p<0.0001). DLCO(RB)/DLCO(SB) was inversely proportional to FEV1% predicted (R = -0.47, p=0.004), and FEV1/FVC (R = -0.54, p<0.001). These data indicate that a 10s single breath DLCO maneuver progressively under-represents re-breathe lung diffusing capacity in emphysema as airflow obstruction increases.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center