Table 2.
Changes in dynamic and static lung volumes, lung mechanics, and pulmonary hemodynamics and gas exchange after LVRS
| Variable | N | Before LVRS | After LVRS | P Value |
|---|---|---|---|---|
| FVC, liters | 14 | 2.41 ± 0.78 | 3.36 ± 0.99 | <0.001 |
| FEV1, liters | 14 | 0.83 ± 0.35 | 1.33 ± 0.82 | 0.004 |
| FEV1, %predicted | 14 | 25 ± 10 | 40 ± 24 | 0.003 |
| FEV1/FVC ratio | 14 | 0.33 ± 0.05 | 0.38 ± 0.15 | 0.24 |
| TLC, liters | 14 | 8.54 ± 1.33 | 7.27 ± 1.70 | 0.04 |
| RV, liters | 14 | 5.54 ± 1.68 | 3.86 ± 1.95 | 0.01 |
| IC, liters | 14 | 1.54 ± 0.40 | 2.04 ± 0.75 | 0.02 |
| DlCO, %predicted | 14 | 27 ± 6 | 37 ± 12 | 0.08 |
| V̇e, l/min | 14 | 8.8 ± 2.3 | 9.0 ± 2.3 | 0.72 |
| Vt, liters | 9 | 0.59 ± 0.09 | 0.61 ± 0.09 | 0.51 |
| Ti, s | 9 | 1.28 ± 0.27 | 1.61 ± 0.32 | 0.01 |
| Te, s | 9 | 3.01 ± 1.92 | 2.80 ± 1.28 | 0.46 |
| Ti/Ttot | 9 | 0.33 ± 0.07 | 0.38 ± 0.05 | 0.003 |
| BF, min−1 | 9 | 16 ± 5 | 15 ± 4 | 0.29 |
| PEEPi, cmH2O | 7 | 3.3 ± 2.4 | 1.7 ± 1.6 | 0.11 |
| MIP, cmH2O | 9 | 53 ± 20 | 69 ± 26 | 0.04 |
| MEP, cmH2O | 9 | 83 ± 24 | 81 ± 26 | 0.82 |
| Cdyn, l/cmH2O | 6 | 0.48 ± 0.17 | 0.34 ± 0.10 | 0.05 |
| Raw, cmH2O · l−1 · s | 6 | 3.34 ± 1.26 | 4.87 ± 2.15 | 0.01 |
| PTPdi, cmH2O/s | 6 | 205 ± 51 | 231 ± 41 | 0.29 |
| TTdi | 6 | 0.06 ± 0.03 | 0.03 ± 0.01 | 0.06 |
| P0.1, cmH2O | 8 | 2.27 ± 1.12 | 1.47 ± 0.44 | 0.04 |
| PAP, mmHg | 13 | 19 ± 5 | 18 ± 4 | 0.10 |
| Q̇t, l/min | 13 | 6.0 ± 2.6 | 5.8 ± 1.6 | 0.79 |
| PVR, dyn · s · cm−5 | 13 | 204 ± 59 | 180 ± 50 | 0.13 |
| PaO2, Torr | 14 | 65 ± 11 | 71 ± 15 | 0.04 |
| PaCO2, Torr | 14 | 42 ± 8 | 38 ± 6 | 0.11 |
| (A-a)Po2, Torr | 14 | 36 ± 10 | 33 ± 17 | 0.41 |
| PV̄O2, Torr | 14 | 35 ± 4 | 36 ± 4 | 0.63 |
| V̇o2, ml/min | 14 | 250 ± 102 | 270 ± 72 | 0.48 |
| Hb, g/dl | 14 | 14.1 ± 1.7 | 14.2 ± 1.7 | 0.90 |
| pH | 14 | 7.41 ± 0.04 | 7.43 ± 0.03 | 0.30 |
| P50 | 14 | 25.7 ± 0.8 | 26.0 ± 0.6 | 0.30 |
| DISP R-E* | 14 | 14.4 ± 6.3 | 13.1 ± 8.2 | 0.59 |
| Shunt, %Q̇t | 14 | 5.0 ± 3.3 | 3.6 ± 2.6 | 0.05 |
| Log SDQ̇ | 14 | 0.79 ± 0.21 | 0.65 ± 0.16 | 0.03 |
| Log SDV̇ | 14 | 1.13 ± 0.30 | 0.99 ± 0.42 | 0.21 |
| Dead space, %V̇e | 14 | 33.7 ± 10.7 | 35.6 ± 6.1 | 0.45 |
| Observed-predicted (A-a)Po2, Torr | 14 | 2.5 ± 10.5 | 4.3 ± 15.8 | 0.65 |
Values are means ± SD; N, no. of subjects. VT, tidal volume; Ti, inspiratory time; Te, expiratory time; Ti/Ttot, inspiratory duty cycle; BF, breathing frequency; PEEPi, intrinsic positive end-expiratory pressure; MIP, maximal inspiratory pressure; MEP, maximal expiratory pressure; Cdyn, dynamic pulmonary compliance; Raw, airway resistance; PTPdi, pressure-time product for the diaphragm; TTdi, tension-time index for the diaphragm; P0.1, inspiratory occlusion pressure; P50, O2 concentration required for half-maximal reduction. P values correspond to significance difference between variables pre- and post-LVRS estimated by paired t-test. Values in bold are ???.