Table 2.
Changes of respiratory dynamics indexes in the two groups (n=60, mean ±sd).
| Index | 1 min | 5 min | 10 min | 15 min | 30 min | 45 min | 60 min | |
|---|---|---|---|---|---|---|---|---|
| PIP (cmH2O) | SP | 13.0±2.9 | 13.3±2.9# | 13.7±2.9# | 13.9±3.0# | 14.7±3.5# | 15.0±3.2# | 15.8±3.5# |
|
| ||||||||
| LP | 14.6±3.8* | 14.7±3.7* | 15.0±4.1* | 15.1±4.1 | 16.4±5.1# | 16.6±5.2# | 14.8±3.1 | |
|
| ||||||||
| Pmean (cmH2O) | SP | 4.0±1.1 | 4.1±1.1 | 4.2±1.1 | 4.2±1.1 | 4.5±1.1# | 4.4±0.9# | 4.7±0.9# |
|
| ||||||||
| LP | 5.9±2.0* | 5.8±1.7* | 6.0±2.0* | 6.0±2.1* | 6.9±3.1*,# | 7.2±3.4* | 5.5±0.6 | |
|
| ||||||||
| Pplateau (cmH2O) | SP | 10.7±2.5 | 10.6±2.8 | 11.3±2.5# | 11.6±2.6# | 12.2±2.9# | 12.3±2.3# | 13.1±2.4# |
|
| ||||||||
| LP | 12.9±3.2* | 12.9±3.3* | 13.0±3.3* | 13.3±3.3* | 14.6±4.4*,# | 14.7±4.7*,# | 13.0±3.2 | |
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| ||||||||
| FImax (L·min−1) | SP | 37.8±4.7 | 38.0±5.3 | 38.5±5.3 | 38.5±4.9 | 38.2±5.0 | 37.6±4.9 | 38.0±5.3# |
|
| ||||||||
| LP | 33.8±3.9* | 33.4±4.2* | 32.9±4.4*,# | 33.4±4.8* | 31.7±5.2*,# | 32.9±5.1* | 32.4±5.7 | |
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| ||||||||
| FEmax (L·min−1) | SP | 24.8±4.8 | 24.8±4.3 | 24.8±4.3 | 24.9±4.4 | 24.2±4.6 | 24.6±5.0 | 24.1±4.4 |
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| ||||||||
| LP | 20.4±4.4* | 19.6±4.2* | 19.4±3.9*,# | 19.5±4.1*,# | 17.6±4.3*,# | 18.0±5.5*,# | 19.4±3.1 | |
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| ||||||||
| Compl (ml·cmH2O−1) | SP | 59.6±10.2 | 58.8±10.9 | 56.7±11.5# | 55.1±12.2# | 52.4±13.4# | 51.1±11.6# | 46.9±10.6# |
|
| ||||||||
| LP | 51.9±12.8* | 51.7±12.5* | 49.5±12.9*,# | 49.0±12.0*,# | 43.8±13.1*,# | 44.1±12.9*,# | 51.5±6.1# | |
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| ||||||||
| VD/VT | SP | 0.16±0.004 | ||||||
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| ||||||||
| LP | 0.21±0.01* | |||||||
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| EtCO2 (mmHg) | SP | 38.7±4.1 | 36.0±3.7# | 35.1±3.0# | 34.2±3.0# | 33.6±2.9# | 34.1±3.4# | 35.8±3.0# |
|
| ||||||||
| LP | 37.0±4.3 | 34.6±3.6*,# | 33.6±3.2# | 33.4±3.5# | 33.5±2.8# | 34.0±3.1# | 33.5±1.3* | |
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| ||||||||
| PaCO2 (mmHg) | SP | 40.7±3.3 | ||||||
| LP | 41.4±3.8 | |||||||
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| ||||||||
| PaO2 (mmHg) | SP | 488.7±120.0 | ||||||
| LP | 465.5±130.5 | |||||||
|
| ||||||||
| Raw (cmH2O·l·s−1) | SP | 9.6±2.9 | 10.2±3.6# | 10.1±3.5# | 10.4±4.0# | 10.8±3.6# | 11.4±4.2# | 11.7±3.6# |
|
| ||||||||
| LP | 11.2±4.8* | 10.5±4.3 | 10.9±4.8 | 11.1±4.9 | 11.9±7.2 | 12.8±7.5 | 10.8±3.1 | |
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| ||||||||
| Re (cmH2O·l·s−1) | SP | 24.2±1.1 | 24.4±1.0 | 26.2±0.9# | 26.8±1.0 | 29.2±1.3# | 30.2±1.3# | 35.0±1.4 |
|
| ||||||||
| LP | 32.34±2.0* | 34.5±2.6*,# | 34.68±3.1* | 35.9±2.9* | 45.5±8.1*,# | 47.0±11.7*,# | 52.4±3.0*,# | |
|
| ||||||||
| WOB (J) | SP | 660.7±54.2 | 651.9±55.2 | 648.6±57.0 | 646.3±59.8 | 643.0±63.5 | 630.6±61.4# | 625.0±67.0# |
|
| ||||||||
| LP | 605.5±68.4* | 603.5±65.4* | 596.0±60.1* | 584.5±57.8*,# | 573.5±57.8* | 586.2±57.6* | 577.2±54.3# | |
Data were presented as mean ±sd;
*
Compared with SP group(P<0.05);
#
Compared with that at 1 min after induction (P<0.05).
PIP – peak airway pressure; Pmean – mean airway pressure; Pplat – inspiratory plateau pressure; FImax – peak inspiratory flow; FEmax – peak expiratory flow; Compl – chest-lung compliance; VD/VT – physiologic dead space in percent of tidal volume; EtCO2 – end-tidal CO2; PaCO2 – arterial partial pressure of carbon dioxide; PaO2 – arterial partial pressure of oxygen Raw: airway resistance; Re – expiratory resistance; WOB – work of breathing.