Transfusion services have a weak evidence base compared to many other modern healthcare practices. Diversity of platelet concentrate quality and deterioration of function during ageing is poorly understood and difficult to measure. No single test is currently suitable to assess concentrate quality for product development purposes or to confirm suitability of individual concentrates for clinical use. Many of the studies in this field investigate the in vitro association between concentrate age and test results. Not all quality indicators are equally informative because a number of storage associated changes correct upon infusion. This study aims to evaluate novel platelet quality assessment techniques that may be of use in determining platelet concentrate quality. The initial stages of the study involved development of reference methods and in vitro assessment of novel techniques for assessing platelet concentrate quality using out of date concentrates. Reference methods included swirl assessment, pH measurement, hypotonic shock response (HSR) and extent shape change (ESC) assays. Novel techniques investigated included the iZON impedance analyser, the ThromboLUX instrument, rotation thromboelastometry (ROTEM) and an automated, simplified version of the HSR test named the automated water expulsion (AWE) test. After initial technical development of the assays, a study of the test results obtained throughout platelet concentrate ageing in the laboratory and under different storage conditions was undertaken. This was followed by a small, proof of concept clinical trial, in which in vitro test results of platelet concentrate samples obtained from the giving set after platelet transfusion were compared to measures of transfusion outcome in myelodisplasia (MDS) patients. Transfusion efficacy was assessed using self assessment bleeding questionnaires and 1 hour post-transfusion corrected count increment (CCI). Although the number of patients included in the trial was too low to reach any definite conclusions, the ThromboLUX, ROTEM and AWE tests all showed enough potential to warrant further investigation as part of a larger clinical trial in the future.
Permanent link to this resource: https://doi.org/10.24384/kn8q-vf14
Dewland, Nicola H.
Supervisors: Harrison, Paul; Brooks, Susan; Baker, Peter
Faculty of Health and Life SciencesDepartment of Biological and Medical Sciences
Year: 2017
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