Table 2.
Ventilatory and hemodynamic variables during the three hours of mechanical ventilation
| VT20/ZEEP | Vt/kg (mL/L)* | PEEP (cmH2O)* | Ppeak (cmH2O)* | Pmean (cmH2O)* | Rrs* | Ers* | Syst AP(mmHg) | Diast AP (mmHg) | Mean AP (mmHg) |
|---|---|---|---|---|---|---|---|---|---|
| Baseline | 19.5 (0.5) | 0.01 (0.04) | 19.5 (1.8) | 4.7 (0.3) | 0.22 (0.02) | 2.77(0.4) | 150 (37) | 126 (31) | 138 (34) |
| 30 min | 19.4 (0.7) | 0.01 (0.02) | 19.6 (1.7) | 4.7 (0.29) | 0.21 (0.03) | 2.80 (0.4) | 147 (31) | 125 (26) | 136 (27) |
| 60 min | 19.2 (0.6) | 0.01 (0.02) | 19.5 (1.6) | 4.7 (0.29) | 0.21 (0.02) | 2.84 (0.4) | 142 (30) | 120 (26) | 131 (27) |
| 90 min | 19.2 (0.8) | 0.01 (0.02) | 19.5 (1.7) | 4.7 (0.29) | 0.21 (0.03) | 2.84 (0.4) | 147 (25) | 125 (21) | 137 (22) |
| 120 min | 19.1 (0.8) | 0.01 (0.01) | 19.4 (1.5) | 4.3 (0.27) | 0.21 (0.03) | 2.86 (0.4) | 133 (29) | 113 (26) | 124 (27) |
| 150 min | 19.4 (1) | 0.02 (0.02) | 19.4 (1.5) | 4.7 (0.23) | 0.20 (0.03) | 2.82 (0.4) | 125 (28) | 106 (27) | 116 (27) |
| 180 min | 19.4 (1) | 0.02 (0.02) | 19.4 (1.5) | 4.7 (0.23) | 0.20 (0.02) | 2.83 (0.4) | 125 (27) | 106 (26) | 116 (26) |
| VT10/PEEP3 | |||||||||
| Baseline | 9.6 (0.3) | 3.3 (0.4) | 16.5 (1.7) | 6.0 (0.4) | 0.31 (0.08) | 4.03 (0.5) | 152 (30) | 128 (26) | 140 (27) |
| 30 min | 9.5 (0.9) | 3.3 (0.4) | 16.6 (1.3) | 6.0 (0.4) | 0.30 (0.08) | 4.13 (0.5) | 131 (21) | 111 (27) | 121 (26) |
| 60 min | 9.5 (1.2) | 3.3 (0.4) | 16.8 (1) | 6.1 (0.3) | 0.32 (0.17) | 4.18 (0.5) | 130 (12) | 109 (14) | 120 (13) |
| 90 min | 9.6 (1.2) | 3.3 (0.4) | 16.3 (1.5) | 6.0 (0.4) | 0.28 (0.05) | 4.07 (0.7) | 124 (19) | 104 (20) | 114 (20) |
| 120 min | 9.6 (1.2) | 3.3 (0.4) | 16.4 (1.3) | 6.0 (0.4) | 0.28 (0.05) | 4.15 (0.6) | 127 (20) | 106 (19) | 117 (19) |
| 150 min | 9.5 (1.2) | 3.3 (0.4) | 16.3 (1.2) | 6.0 (0.4) | 0.26 (0.04) | 4.15 (0.6) | 116 (16) | 96 (17) | 107 (16) |
| 180 min | 9.5 (1.1) | 3.3 (0.5) | 16.4 (1.0) | 6.0 (0.3) | 0.27 (0.04) | 4.22 (0.5) | 117 (24) | 95 (25) | 106 (25) |
VT20/ZEEP: tidal volume = 20 mL/kg and zero end-expiratory pressure (PEEP = 0 cmH2O); VT10/PEEP3: tidal volume = 10 mL/kg and positive end-expiratory pressure = 3 cmH2O. Rrs = resistance of the respiratory system (cmH2O/L/s); Ers = elastance of the respiratory system (cmH2O/L). Data are expressed as mean (standard deviation). *P < 0.05.