Measurement | PEEP 5 cm H2O (N= 10) | PEEP 10 cm H2O (N= 10) | PEEP 15 cm H2O (N= 10) | P value |
---|---|---|---|---|
Arterial blood gas measurements | ||||
   PaO2, mmHg | 74 ± 15b | 90 ± 19c | 102 ± 26d | <0.001 |
   PaCO2, mmHg | 51 ± 11 | 50 ± 10 | 52 ± 12 | NS (0.08) |
   pH | 7.31 ± 0.09 | 7.32 ± 0.09c | 7.3 ± 0.09d | 0.002 |
   SaO2, % | 94 ± 3e | 97 ± 3 | 97 ± 3f | <0.001 |
   PaO2/FiO2 | 106 ± 35e | 133 ± 43c | 153 ± 57f | <0.001 |
Haemodynamic and ventilatory parameters | ||||
   SAP, mmHg | 126 ± 18 | 120 ± 15 | 122 ± 19 | NS (0.39) |
   DAP, mmHg | 51 ± 11 | 50 ± 7 | 53 ± 10 | NS (0.4) |
   MAP, mmHg | 76 ± 10 | 74 ± 7 | 75 ± 11 | NS (0.6) |
   HR, beats/minute | 85 ± 14 | 83 ± 14 | 85 ± 14 | NS (0.6) |
   PIP, cmH2O | 34 ± 6 | 37 ± 10c | 43 ± 12 | NS (0.06) |
   MIP, cmH2O | 12 ± 2e | 18 ± 2c | 22 ± 3g | <0.001 |
Lung sonographic evaluation | ||||
   Nonaerated lung area, cm2 | 27 ± 31e | 20 ± 24c | 11 ± 12f | 0.008 |