Bone marrow harvesting for allogeneic transplantation - evaluation of ten years' experience focusing on donor auto-transfusion utilisation
Abstract
Bone marrow (BM) is one of the sources of hematopoietic stem cells used for allogeneic transplantation. In this retrospective study, we analysed bone marrow harvests in 216 healthy donors over a ten-year period (2007-2017).
Larger volumes of bone marrow were obtained from male compared to female donors (1300 ml vs. 1100 ml) due to their higher body weight, resulting in a higher number of nucleated cells (156 vs. 124 x 106 TNC, ns). The total yield was dependent on the volume of marrow (p < 0.0001) and donor weight (p = 0.01).
Suboptimal grafts containing <= 2.0 x 108 TNC/kg (recipient) were collected in 6 % of cases, always with significant differences of weight between donor and recipient (median 20 kg). All donors underwent preoperative autologous blood donation (PAD).
The initial haemoglobin level of 153 g/L (male donors) and 135 g/L (female donors) decreased by about 8 g/L after preoperative blood donation and by 23 g/L after bone marrow harvest. Auto-transfusion was administered to 70 % of donors, 30 % of the units remained unused.
Evaluation of the risk of reaching transfusion threshold (<115 g/L males, < 105 g/L females) revealed that donors with initial haemoglobin level above 145 g/L and those weighing more than 75 kg have a minimal risk of requiring blood substitution (about 10 %). The incidence of adverse events associated with bone marrow harvests was low (5 %) and none of these were classified as serious.
The analysis proved that the amount of nucleated cells harvested and substitution requirements are determined by donor parameters (weight, haemoglobin level) and recipient parameters (weight). Given the changing policy to auto-transfusion during bone marrow collection, the issue of balancing the benefits and risks of administering preoperative autologous transfusion should be addressed.