[Comparative validation of manual and automated methods for mixing and volume control of total blood samples].

During blood collection, agitation and volume limitations are critical to ensure thorough mixing of the blood with the anticoagulant and obtention of the predetermined volume. These 2 factors are essential to prevent blood activation and to obtain well standardized blood products. The objective of this study was to compare the quality of the blood collected using 2 types of collection method: tripping of a scale at a predetermined volume limit of 450 mL in the presence of manual agitation, and the 3 blood collection monitors currently available in France. A minimum of 100 collection procedures was performed for each of the 4 methods tested. Results were found to be equivalent using either the manual or the automated procedures with regard to both the accuracy and reproducibility of the blood volumes obtained and the collection times and flow rates. The characteristics of the red blood cell concentrates, platelet concentrates and plasma units prepared from the first 30 collections of each group were assessed and compared to regulatory requirements. The quality of all these products was found to be comparable to that currently observed at quality control and no product was rejected at the release control for reasons of poor collection. An assessment of the practicability of the different methods showed that the automated devices are subject to practical difficulties involving transport and battery loading. In addition, the cost of this equipment is approximately 5 times higher than that of the scales. In conclusion, the results of this study show that in our hands, no significant advantage could be expected from the use of automated blood collection monitors as compared to simple scales with manual mixing. These results further raise the question of the applicability to labile blood products of the comparative validations currently accepted in the pharmaceutical industry, in order to allow the use of correctly validated alternative methods.