Homologous transfusion is associated with infectious and immunological risks. Preoperative autologous deposit reduces homologous transfusion requirements considerably. Usually donations are carried out at weekly intervals. In this study we investigated the effect of shorter donation intervals on erythropoiesis and perioperative transfusion requirements. METHODS. A total of 40 consecutive patients scheduled for hip arthroplasty and taking part in an autologous donation
programme were randomly assigned to two groups: group I gave blood on days 0, 3, 7 (and 14), group II at weekly intervals. The aim was deposit of three blood units of 450 ml. A patient was deferred if hemoglobin concentration prior to donation fell below 11 g/dl, and in this case 100 mg Fe 2+ three times daily was prescribed. Blood was stored with CP-DA-1 anticoagulant. Surgery was performed between day 28 and 35. A perioperative hemoglobin concentration lower than 9 g/dl was considered a transfusion trigger. RESULTS. Group I was made up of 21 patients (10 women, 11 men, aged 39-69 years) who gave blood at short intervals, and group II of 19 patients (10 women, 9 men, aged 37-77 years) who gave blood at weekly intervals. General data, calculated blood volume and erythrocyte mass prior to donation were comparable. Each patient donated three units. Four patients had to be deferred once, one in group I, three in group II. The hemoglobin concentration in group I decreased from 13.9 +/- 1.2 g/dl (mean +/- SD) to 13.3 +/- 1.0 g/dl prior the operation, in group II from 13.5 +/- 1.3 g/dl to 12.5 +/- 1.1 g/dl. Preoperatively the hemoglobin concentrations differed significantly (P < 0.05), as did calculated erythrocyte mass (1633 versus 1474 ml, P < 0.05). Reticulocytes increased from 46 x 10(3)/microliters (median) to a maximum of 94 x 10(3)/microliters on day 7 in group I, and from 44 x 10(3)/microliters to 108 x 10(3)/microliters in group II on day 14. Serum ferritin decreased from 122 micrograms/l (median) to 82 micrograms/l in group I, and from 140 micrograms/l to 77 micrograms/l in group II. These parameters did not differ statistically between the two groups. Intra- and postoperative blood loss amounted to 2175 ml (median) in group I versus 1430 ml in group II (P < 0.05). The perioperative hemoglobin concentration was similar in the two groups. Homologous transfusion requirements were similar in the two groups (1 unit in group I, vs 3 units in one patient and 1 unit in two patients in group II). CONCLUSIONS. Short donation intervals resulted in a higher preoperative erythrocyte mass after similar preoperative deposit, and significantly higher blood loss was tolerated with similar homologous transfusion volume.