Table 1.
Respiratory mechanics and gas exchange during ventilation with tidal volumes of 6 and 3 ml/kg PBW
| 6 ml/kg PBW | 3 ml/kg PBW | p | |
|---|---|---|---|
| Tidal volume (ml) | 400 (378–443) | 215 (190–225) | |
| Respiratory rate (min−1) | 12 (10–13) | 12 (10–14) | 0.096 |
| Plateau pressure (cmH2O) | 18 (17–20) | 15 (13–17) | 0.003 |
| PEEP (cmH2O) | 6 (5–7) | 8 (6–8) | 0.034 |
| Driving pressure (cmH2O) | 12 (10–14) | 7 (6–9) | 0.003 |
| Respiratory system compliance (ml/cmH2O) | 35 (29–40) | 27 (23–32) | 0.013 |
| EELV (ml) | 904 (664–1043) | 538 (494–827) | 0.024 |
| Strain | 0.50 (0.43–0.59) | 0.38 (0.24–0.50) | 0.529 |
| PaO2 (mmHg) | 100 (86–111) | 97 (80–120) | 0.782 |
| PaCO2 (mmHg) | 36 (32–37) | 39 (36–44) | 0.074 |
| pH | 7.45 (7.43–7.50) | 7.40 (7.34–7.45) | 0.027 |
| FiO2 | 0.40 (0.35–0.50) | 0.40 (0.35–0.50) | 0.635 |
| FECMOO2 | 0.65 (0.60–0.80) | 0.70 (0.60–0.80) | 0.283 |
| ECMO blood flow (l/min) | 3.1 (2.9–3.7) | 3.3 (2.9–3.5) | 0.327 |
| ECMO sweep flow (l/min) | 3.0 (2.38–5.00) | 5.0 (3.5–6.5) | 0.004 |
| Fluid balance (l) | 0.736 (-0.19–2.34) | 1.725 (508–3.165) | 0.377 |
| Urine output (l) | 1.57 (0.85–2.88) | 1.18 (0.88–2.16) | 0.206 |
| Creatinine (mg/dl) | 1.12 (0.80–1.41) | 1.22 (0.79–2.11) | 0.804 |
| Urea (mg/dl) | 58 (33.5–77.5) | 57 (40.25–79.75) | 0.974 |
| Use of RRT (n) | 2 | 2 | 1 |
| Haemoglobin (g/dl) | 9.1 (8.85–10.05) | 8.8 (8.47–9.47) | 0.083 |
Baseline kidney function and haemoglobin values are also depicted. Data are expressed as median (interquartile range)
PEEP positive end-expiratory pressure, RRT: renal replacement therapy, EELV: end-expiratory lung volume. EELV and strain were measured in only nine patients