Table 2.
Stability/drift results, showing the mean ± SD values measured by MetaMax 3B of FEO2, and FECO2, as recorded from the calibration gas bottle, as well as VO2 and VCO2 at different metabolic rates (low, medium, high) as simulated by the Gas Exchange System Validator, over a 180-min period
| Time (min) | FEO2 (%) | FECO2 (%) | VO2 (L min−1) | VCO2 (L min−1) | ||||
|---|---|---|---|---|---|---|---|---|
| Low | Med | High | Low | Med | High | |||
| 0 | 15.84 ± 0.00 | 4.10 ± 0.02 | 0.30 ± 0.00 | 1.67 ± 0.02 | 2.82 ± 0.03 | 0.28 ± 0.00 | 1.57 ± 0.02 | 2.66 ± 0.04 |
| 20 | 15.85 ± 0.00 (0.1***) | 3.94 ± 0.04 (−3.9***) | 0.30 ± 0.00 (−0.1) | 1.66 ± 0.01 (−0.4) | 2.81 ± 0.04 (−0.5) | 0.29 ± 0.00 (1.5***) | 1.58 ± 0.02 (0.7) | 2.68 ± 0.04 (1.1*) |
| 40 | 15.87 ± 0.00 (0.2***) | 3.99 ± 0.03 (−2.7***) | 0.30 ± 0.00 (−0.7) | 1.67 ± 0.01 (0.1) | 2.82 ± 0.03 (−0.2) | 0.28 ± 0.01 (0.7) | 1.58 ± 0.01 (1.1*) | 2.68 ± 0.03 (0.8) |
| 60 | 15.88 ± 0.00 (0.3***) | 3.97 ± 0.03 (−3.2***) | 0.31 ± 0.00 (2.0***) | 1.67 ± 0.02 (−0.2) | 2.83 ± 0.03 (0.3) | 0.29 ± 0.00 (3.4***) | 1.58 ± 0.02 (0.8) | 2.67 ± 0.03 (0.4) |
| 80 | – | – | 0.31 ± 0.00 (2.8***) | 1.68 ± 0.02 (0.6) | 2.84 ± 0.03 (0.9) | 0.29 ± 0.00 (3.8***) | 1.59 ± 0.02 (1.3*) | 2.68 ± 0.04 (1.1) |
| 100 | – | – | 0.31 ± 0.00 (2.7***) | 1.68 ± 0.01 (0.6) | 2.85 ± 0.03 (1.0*) | 0.29 ± 0.00 (3.5***) | 1.58 ± 0.01 (0.6) | 2.68 ± 0.04 (1.0) |
| 120 | 15.91 ± 0.00 (0.4***) | 4.05 ± 0.03 (−1.2***) | 0.31 ± 0.00 (2.6***) | 1.69 ± 0.02 (1.1*) | 2.84 ± 0.03 (0.8) | 0.29 ± 0.00 (3.2***) | 1.58 ± 0.02 (1.0) | 2.67 ± 0.05 (0.4**) |
| 140 | – | – | 0.31 ± 0.00 (2.7***) | 1.69 ± 0.01 (1.0**) | 2.86 ± 0.03 (1.5***) | 0.29 ± 0.00 (3.2***) | 1.58 ± 0.02 (0.8) | 2.69 ± 0.03 (1.3) |
| 160 | – | – | 0.31 ± 0.00 (2.6***) | 1.69 ± 0.02 (1.3**) | 2.85 ± 0.03 (1.0*) | 0.29 ± 0.00 (2.8***) | 1.58 ± 0.02 (0.8) | 2.68 ± 0.04 (0.8*) |
| 180 | 15.93 ± 0.00 (0.6***) | 4.05 ± 0.03 (−1.2***) | 0.31 ± 0.00 (2.1***) | 1.69 ± 0.01 (1.3***) | 2.87 ± 0.03 (1.8***) | 0.29 ± 0.00 (2.1***) | 1.58 ± 0.01 (0.7) | 2.69 ± 0.04 (1.1) |
The resultant relative percentage error in comparison with baseline, at time = 0, is shown in brackets
Significantly different to time at 0 min (ANOVA)
Error (%) difference between FEO2, FECO2, VO2 or VCO2 values as [each time (min)−baseline (0 min)]/value of baseline × 100%, and was calculated from mean data expressed as four decimal places
* p < 0.05
** p < 0.01
*** p < 0.001