Table 1. Physiological and EPR parameters following 20% transfusion with Hb–DBBF.
Physiological and EPR data for animals undergoing control transfusions of autologous blood (n=7) and those undergoing transfusions with DBBF (n=6). All data are means±S.D. In the Hb–DBBF group, data were corrected for the blood removed by the drop in haematocrit. The methaemoglobin concentration in the EPR samples was calculated by comparing the size of the strong high-field feature (g=6) with that of a pure methaemoglobin standard of known concentration. To remove the problem of the low-field (g=1.99) feature of the methaemoglobin signal interfering with the quantification of the other signals, the blood/plasma EPR spectra had the appropriate level of a pure haemoglobin spectrum subtracted from them before quantification of the other signals in this region. The ceruloplasmin and erythrocyte globin radical concentrations were then calculated by comparison of the second integrals of the respective signals with a copper EDTA standard, measured at non-saturating conditions for all species. The concentration of iron bound to transferrin was calculated by comparison of transferrin signals with that of a standard of human ferric transferrin of known concentration. Transferrin standards were prepared by the addition of atomic absorption standard iron in 1% HCl to excess human apotransferrin (a gift from Dr Robert Evans, King's College London, London, U.K.). Two-way ANOVA showed significant differences between control and Hb-DBBF for the following parameters: MAP, haematocrit, transferrin-bound iron and methaemoglobin. bpm, beats per minute.
| Time (min after transfusion) | ||||||||
|---|---|---|---|---|---|---|---|---|
| Parameter | Pre-transfusion control | 5 | 15 | 30 | 60 | 120 | 180 | |
| MAP (mm Hg) | +DBBF | 80.8±11.9 | 93.8±9.2* | 91.7±10.7 | 98.0±13.0† | 94.4±9.1† | 88.1±12.7 | 92.3±7.7† |
| Control | 80.1±12.9 | 81.1±11.5 | 75.5±13.5 | 78.3±12.8 | 73.3±8.8 | 71.9±10.5 | 70.4±9.9 | |
| Heart rate (bpm) | +DBBF | 264.2±21.5 | 234.2±30.4* | 219.2±41.5 | 232.5±32.0 | 233.3±22.3 | 226.0±35.8 | 240.0±34.5 |
| Control | 249.3±25.2 | 246.7±25.2 | 248.3±27.3 | 245.0±32.7 | 237.5±25.6 | 241.4±26.1 | 229.3±28.2 | |
| Blood pH | +DBBF | 7.38±0.04 | 7.40±0.03 | 7.40±0.04 | 7.40±0.04 | 7.41±0.05 | 7.42±0.03 | 7.43±0.04 |
| Control | 7.37±0.06 | 7.39±0.03 | 7.39±0.02 | 7.39±0.03 | 7.39±0.03 | 7.38±0.02 | 7.40±0.03 | |
| Haematocrit | +DBBF | 40.9±3.6 | 31.5±3.6* | 30.9±3.6† | 30.5±3.2† | 31.0±3.5† | 29.8±3.0† | 29.7±3.0† |
| Control | 37.6±3.0 | 36.6±2.8 | 37.0±2.3 | 36.7±2.2 | 37.0±1.9 | 35.0±2.2 | 35.0±2.4 | |
| Total Hb (g/dl) | +DBBF | 12.5±1.7 | 11.1±1.0* | 10.9±1.2 | 11.0±1.2 | 11.1±1.3 | 10.7±1.0 | 10.5±0.5 |
| Control | 11.9±0.9 | 11.4±0.6 | 11.7±0.5 | 11.7±1.3 | 11.4±0.7 | 11.2±1.1 | 10.8±0.7 | |
| Ceruloplasmin (μM) | +DBBF | 1.53±1.27 | 1.48±0.91 | 1.60±1.32 | 1.73±1.45 | 1.87±1.57 | 1.71±1.75 | 1.62±1.60 |
| Control | 2.47±1.81 | 2.29±1.71 | 2.37±1.84 | 2.35±1.81 | 2.37±1.71 | 2.35±1.81 | 2.41±1.75 | |
| Transferrin iron (μM) | +DBBF | 11.40±2.03 | 17.14±3.55* | 17.50±3.43† | 18.16±3.69† | 18.68±3.56† | 20.03±4.54† | 18.79±5.66† |
| Control | 10.74±4.09 | 9.55±3.01* | 9.47±3.52 | 9.46±3.59 | 9.23±3.26 | 8.56±2.71 | 8.08±2.30 | |
| Erythrocyte radical (μM) | +DBBF | 0.083±0.061 | 0.064±0.026 | 0.071±0.033 | 0.089±0.031 | 0.047±0.026 | 0.058±0.062 | 0.051±0.046 |
| Control | 0.053±0.012 | 0.049±0.017 | 0.041±0.007 | 0.088±0.075 | 0.046±0.015 | 0.046±0.011 | 0.045±0.018 | |
| MetHb (μM) | +DBBF | 3.38±1.23 | 33.36±9.75*‡ | 29.09±8.08† | 23.17±8.11† | 15.17±7.00† | 8.21±3.02 | 6.48±2.95 |
| Control | 2.69±1.05 | 2.49±0.82 | 2.56±0.80 | 2.63±0.90 | 2.41±0.71 | 2.64±0.55 | 2.61±0.81 | |
*Immediate post transfusion value (t=5) significantly different from pre-transfusion value.
†Significantly different from control (two-way ANOVA with Bonferroni post test).
‡Significant linear trend (one-way ANOVA) from post transfusion (t=5) to the end of the study (t=180).