Changes in frational oxygen extraction (FOE) and haemoglobin concentration (Hb) with transfusion
| FOE | Significance of change in FOE | Hb (g/l) | |||
|---|---|---|---|---|---|
| Indication for transfusion | Before transfusion | After transfusion | Before transfusion | After transfusion | |
| FOE values are given as mean (SD); Hb values are given as median (interquartile range). | |||||
| NIRS, near infrared spectroscopy. | |||||
| NIRS | |||||
| High FOE | 0.508 (0.06) | 0.328 (0.06) | p<0.001 | 88 (75–97) | 130 (125–169) |
| Mean change (95% CI) | 0.180 (0.136 to 0.225) | Mean change (95% CI) | −46 (−52 to −40) | ||
| Low Hb, high Fio2 | 0.340 (0.06) | 0.298 (0.06) | p=0.005 | 98 (80–111) | 145 (119–148) |
| Mean change (95% CI) | 0.052 (0.021 to 0.084) | Mean change (95% CI) | −43 (−50 to −36) | ||
| Symptoms | 0.355 (0.05) | 0.333 (0.04) | p=0.07 | 87 (76–105) | 130 (125–169) |
| Mean change (95% CI) | 0.031 (0.0037 to 0.066) | Mean change (95% CI) | −54 (−73 to −35) | ||
| Conventional | |||||
| Low Hb | 0.351 (0.05) | 0.299 (0.06) | p=0.01 | 121 (108–130) | 155 (146–168) |
| Mean change (95% CI) | 0.053 (0.032 to 0.073) | Mean change (95% CI) | −39 (−43 to −34) | ||
| Symptoms | 0.415 (0.07) | 0.332 (0.08) | p=0.02 | 102 (92–114) | 141 (134–160) |
| Mean change (95% CI) | 0.082 (0.018 to 0.147) | Mean change (95% CI) | −43 (−52 to −33) | ||