Table 1.
Dynamic and static lung volumes, pulmonary hemodynamics, and gas exchange before LVRS
| Variable | |
|---|---|
| N | 23 |
| Age, yr | 62 ± 8 |
| Sex (men/women) | 21/2 |
| Height, cm | 170 ± 10 |
| Weight, kg | 65 ± 14 |
| FVC, %predicted | 60 ± 16 |
| FEV1, liters | 0.84 ± 0.33 |
| FEV1, %predicted | 26 ± 10 |
| FEV1/FVC ratio | 0.33 ± 0.06 |
| TLC, %predicted | 127 ± 18 |
| RV, %predicted | 237 ± 54 |
| IC, liters | 1.57 ± 0.34 |
| DlCO, %predicted | 30 ± 9 |
| PaO2, Torr | 65 ± 11 |
| PaCO2, Torr | 41 ± 7 |
| (A-a)Po2, Torr | 37 ± 10 |
| PV̄O2, Torr | 33.6 ± 4.1 |
| V̇e, l/min | 8.7 ± 2.3 |
| V̇o2, ml/min | 251 ± 87 |
| PAP, mmHg | 18 ± 5 |
| Q̇t, l/min | 4.99 ± 1.12 |
| CI, l · min−1 · m−2 | 2.76 ± 0.50 |
| PVR, dyn · s · cm−5 | 192 ± 51 |
| V̇a/Q̇ inequality | |
| RSS | 4.4 ± 3.2 |
| DISP R-E* | 13.6 ± 5.5 |
| Shunt, %Q̇t | 4.1 ± 2.8 |
| Low, V̇a/Q̇, %Q̇t | 0.01 ± 0.02 |
| Mean Q̇ | 0.79 ± 0.29 |
| Log SDQ̇ | 0.77 ± 0.23 |
| High, V̇a/Q̇, %V̇e | 2.58 ± 3.71 |
| Mean V̇ | 2.00 ± 0.54 |
| Log SDV̇ | 1.13 ± 0.40 |
| Dead space, %V̇e | 33.3 ± 10.2 |
| Predicted-observed PaO2, Torr | −0.5 ± 4.6 |
| Observed-predicted (A-a)Po2, Torr | 2.6 ± 10.3 |
Values are means ± SD; N, no. of subjects. Spirometric data are prebronchodilator values. FVC, forced vital capacity; FEV1, forced expiratory volume in 1 s; TLC, total lung capacity; RV, residual volume; IC, inspiratory capacity; DlCO, transfer factor for carbon monoxide; PaO2, partial pressure of oxygen in arterial blood; PaCO2, partial pressure of carbon dioxide in arterial blood; (A-a)Po2, alveolar-arterial oxygen partial pressure gradient; PV̄O2, mixed venous partial pressure of oxygen; V̇e, minute ventilation; V̇o2, oxygen uptake; PAP, mean pulmonary arterial pressure; Q̇t, cardiac output; CI, cardiac index; PVR, pulmonary vascular resistance; V̇a/Q̇, ventilation-perfusion; RSS, residual sum of squares of the best fit to the excretion and retention data; DISP R-E*, dispersion of retention minus excretion of inert gases corrected for dead space, an overall index of V̇a/Q̇ heterogeneity; shunt, percentage of blood flow to very low V̇a/Q̇ units (<0.005); low, V̇a/Q̇, %Q̇t: blood flow to units with V̇a/Q̇ ratios between 0.005 and 0.1; mean Q̇, mean V̇a/Q̇ ratio of the blood flow distribution; log SDQ̇, the second moment blood flow distribution; high, V̇a/Q̇, %V̇e: ventilation to units with V̇a/Q̇ ratios between 10 and 100; mean V̇, mean V̇a/Q̇ ratio of the ventilation distribution; log SDV̇, the second moments of the ventilation distribution; dead space, fraction of ventilation to dead space.