Table 2.
Comparison of the parameters at peak exercise between treatments with tiotropium and oxitropium in constant workload exercise testing
| Tiotropium | Oxitropium | P value | |
|---|---|---|---|
| Endurance time (s) | 504 ± 291 | 397 ± 201 | 0.007 |
| Work rate (W) | 37.8 ± 14.0 | 32.5 ± 13.3 | <0.001 |
| Oxygen uptake (mL/minute) | 756 ± 227 | 795 ± 267 | 0.031 |
| Carbon dioxide production (mL/minute) | 768 ± 256 | 799 ± 304 | |
| Oxygen uptake/weight (mL/kg/minute) | 13.3 ± 4.0 | 14.1 ± 4.6 | 0.035 |
| Minute ventilation (L/minute) | 30.7 ± 7.9 | 31.1 ± 9.6 | |
| IC (mL) | 1536 ± 494 | 1508 ± 493 | |
| Heart rate (beats/minute) | 118 ± 16.1 | 115 ± 17.3 | |
| SpO2 (%) | 91.4 ± 4.6 | 90.8 ± 3.7 | |
| Dyspnea index (%)a | 86.2 ± 17.7 | 98.2 ± 21.8 | 0.002 |
| HR/predicted maximum HR (%)b | 78.5 ± 11.0 | 76.8 ± 12.3 |
Notes:
a
Dyspnea index (%) = (minute ventilation at peak exercise)/(maximal voluntary ventilation) × 100;
b
predicted maximum HR (adult) = 220 − age (years).
Abbreviations: HR, heart rate; IC, inspiratory capacity; SpO2, oxygen saturation.