Table 3.
Blood and respiratory variables
| Baseline (PSV) | PSV | Noisy PSV | |
|---|---|---|---|
|
pH |
7.41 ± 0.13 |
7.41 ± 0.05 |
7.41 ± 0.05 |
|
HCO
3
-
(mmol/L) |
27.1 ± 4.0 |
27.1 ± 3.8 |
27.2 ± 3.8 |
|
BE |
3.0 ± 3.9 |
2.9 ± 3.8 |
3.0 ± 3.8 |
|
Lactate (mmol/L) |
1.2 ±0.4 |
1.0 ± 0.3 |
1.1 ±0.3 |
|
Lowest V
T
/kg IBW (mL/kg) |
4.6 ± 2.3 |
5.3 ± 2.3 |
3.0 ± 1.6** |
|
Mean V
T
/kg IBW (mL/kg) |
9.0 ± 1.8 |
9.0 ± 1.3 |
8.7 ± 1.3 |
|
Highest V
T
/kg IBW (mL/kg) |
13.1 ± 5.8 |
12.6 ± 3.4 |
14.3 ± 4.0* |
|
RR (/min) |
18.8 ± 6.0 |
18.9 ± 7.0 |
19.0 ± 6.4 |
| T i /T tot | 0.3 ± 0.1 | 0.3 ± 0.1 | 0.3 ± 0.1 |
Values are mean ± standard deviation (SD). PSV, pressure support ventilation; BE, base excess; VT/kg IBW, tidal volume per kg of ideal body weight; RR, respiratory rate, TI/Ttot, ratio of inspiratory time to total breath duration. Statistical significance according to Wilcoxon paired, two-sided signed rank test between PSV and noisy PSV at P <0.05. *, P <0.05; **, P <0.01.