Measured and calculated cardiac variables
| H0 | H30 | R0 | R30 | R90 | R150 | |
|---|---|---|---|---|---|---|
| Values are mean (SEM). Hypoxaemia was induced in all the experimental animals. They were then randomised to one of two groups and resuscitated with either 21% or 100% O2. Measurements were made at baseline (H0), 30 minutes after the start of hypoxaemia (H30), at the start of reoxygenation (R0), and at 30, 90, and 150 minutes of reoxygenation (R30, R90, and R150). | ||||||
| Peak tricuspid regurgitation velocity (m/s) | ||||||
| Sham | – | 2.46 (0.04) | 2.30 (0.03) | 2.28 (0.05) | 2.39 (0.07) | 2.35 (0.05) |
| 21% | 2.14 (0.36) | 3.14 (0.07) | 3.02 (0.19) | 3.04 (0.13) | 2.69 (0.13) | 2.81 (0.10) |
| 100% | 2.62 (0.18) | 2.95 (0.08) | 2.96 (0.20) | 2.90 (0.20) | 2.69 (0.08) | 2.88 (0.13) |
| Cardiac output (litres/min/kg) | ||||||
| Sham | 0.340 (0.04) | 0.331 (0.09) | 0.302 (0.06) | 0.329 (0.08) | 0.304 (0.03) | 0.305 (0.04) |
| 21% | 0.281 (0.02) | 0.424 (0.03) | 0.336 (0.03) | 0.378 (0.02) | 0.356 (0.02) | 0.347 (0.02) |
| 100% | 0.371 (0.04) | 0.417 (0.03) | 0.513 (0.06) | 0.415 (0.04) | 0.401 (0.04) | 0.403 (0.05) |
| Heart rate (beats/min) | ||||||
| Sham | 132 (9) | 139 (8) | 128 (8) | 134 (13) | 134 (7) | 130 (14) |
| 21% | 152 (9) | 202 (12) | 174 (21) | 183 (12) | 178 (11) | 164 (13) |
| 100% | 165 (12) | 198 (11) | 172 (18) | 186 (14) | 201 (14) | 179 (11) |
| Stroke volume (ml/kg) | ||||||
| Sham | 2.44 (0.43) | 2.40 (0.89) | 2.38 (0.61) | 2.44 (0.63) | 2.30 (0.38) | 2.42 (0.41) |
| 21% | 2.01 (0.45) | 2.02 (0.45) | 2.01 (0.58) | 2.15 (0.54) | 2.05 (0.45) | 2.09 (0.40) |
| 100% | 2.40 (0.54) | 2.07 (0.37) | 2.47 (0.69) | 2.17 (0.48) | 2.03 (0.50) | 2.29 (0.88) |