Static lung volumes and gas diffusion for 107 patients separated by degree of impairment of FEV1
| Impairment of FEV1 | ||||
|---|---|---|---|---|
| None (n=31) | Mild (n=19) | Moderate (n=36) | Severe (n=21) | |
| RV (l) | 2.02 (0.44) | 2.45 (0.65) | 3.09 (0.69)3-160 | 3.73 (0.79)3-150 |
| RV (% predicted) | 96.0 (17.1) | 113.4 (26.6)3-150 | 138.3 (28.6)3-150 | 155.1 (31.5)3-150 |
| TLC (l) | 5.65 (1.24) | 5.81 (1.14) | 6.35 (1.31) | 6.5 (1.28) |
| TLC (% predicted) | 102.3 (11.8) | 103.1 (15.1) | 110.6 (14.6) | 106.4 (12.9) |
| RV/TLC (%) | 36.3 (5.9) | 42.1 (7.3)3-150 | 49.1 (7.7)3-160 | 57.8 (7.7)3-160 |
| RV/TLC (% predicted) | 92.4 (12.6) | 107.1 (14.6)3-150 | 122.5 (18.4)3-150 | 142.3 (21.4)3-160 |
| Tlco (mmol/min/kPa) | 7.66 (2.39) | 7.6 (2.3) | 6.28 (2.1)3-164 | 5.5 (1.67)3-164 |
| Tlco (% predicted) | 96.9 (23.6) | 94.6 (21.1) | 79.4 (21.5) | 69.3 (18.1)3-170 |
| Kco (mmol/min/kPa/l) | 1.5 (0.3) | 1.57 (0.45) | 1.26 (0.43)3-151 | 1.22 (0.38)3-151 |
| Kco (% predicted) | 104.7 (23.9) | 111.3 (30.8) | 90.5 (30.9) | 94.1 (26.3) |
RV = residual volume; TLC = total lung capacity; Tlco = carbon monoxide gas transfer factor; Kco= carbon monoxide gas tranfer coefficient (Tlcodivided by effective alveolar volume).
All values are means (SD).
↵3-150 p<0.05;
↵3-160 p<0.01;
3-165 p<0.001 compared with the adjacent less severe category of FEV1 impairment (one way ANOVA with post-hoc comparison).
↵3-151 p<0.05 severe and moderate versus mild impairment;
↵3-164 p<0.01 severe and moderate versus no impairment;
↵3-170 p<0.001 severe versus no impairment.