Objectives: To compare three techniques for decreasing homologous blood requirements in total hip arthroplasty (THA), including preoperative autologous donation (PAD), preoperative acute normovolaemic haemodilution with erythrocytapheresis (erythro) and intraoperative normovolaemic haemodilution (haemo).
Study design: Prospective clinical trial.
Patients: The study included 45 patients scheduled for THA, under general anaesthesia and operated on by the same surgeon. The patients were allocated into three groups of 15 each.
Methods: Blood loss was assessed, during surgical procedure, by the weight of sponges and, the amount of blood collected in the suction bottles during and after surgery. The haemoglobin concentration was measured at the time of preoperative assessement (d-30), just prior to surgery (d-1), in the recovery room (d+3h), and 1, 3, and 8 days later (d8). The transfusion end-point in the three groups was to obtain a haemoglobin concentration of 100 g.L-1 from d+3h until d8. Every pack of red blood cells transfused was weighed and its haematocrit assessed to determine the accurate volume of red blood cells.
Results: In the three groups haemoglobin concentration was similar from d+3h until d8. In the PAD group, no patient required homologous blood transfusion. There was no significant difference between the two other groups in the mean volume of homologous red blood cells required (308 +/- 197 mL in erythro group and 331 +/- 202 mL in the haemo group, respectively). The intraoperative blood loss was significantly higher (P = 0.001) in the erythro group: 914 +/- 305 mL vs 665 +/- 263 in the PAD group and 512 +/- 146 mL in the haemo group, respectively. There was an inverse correlation between haematocrit at d-1 and intraoperative bleeding (r = -0.7) (P = 0.0001). The distribution of the points was fitted as an exponential curve.
Conclusions: In THA, PAD is obviously the best technique to avoid homologous blood transfusion. However, when PAD is not feasible, removal of blood prior to surgery does not decrease requirements of homologous blood, as intraoperative blood loss is higher. Our results strongly question the use of major haemodilution during a surgical procedure exposing a major blood loss.