[Characterization of mechanical in vitro hemolysis and sub-hemolysis. 2: Variables of state and dimensionless characteristic values of hemolysis].
Blood damaging effects of artificial perfusion devices such as assist devices, heart valve prostheses, for example, must be evaluated in vitro before being used in the clinical setting. For this purpose, mainly animal blood has been used, and a number of associated problems are currently being discussed. Differences in the use of the term hemolysis--meaning breakdown of erythrocytes or increased plasma hemoglobin, result in incompatibility among different authors. In addition, subhemolytic damage and its quantification has not been investigated to any extent. Another problem are the differences in the mechanical fragility of erythrocytes from different animal species, and the question of transferability to the in vivo situation. Furthermore, the variability of mechanical stability within a given species is often greater than the differences between one species and another. International efforts are now being made to standardize haemolytic test conditions and the present study is meant as a contribution to this. In the first part we describe an extension of our LYSE number model. Characteristically, the model uses dimensionless similarity numbers, LY and MY, thus making the results obtained under different test conditions comparable with one another. The LY number reflects the breakdown of cells (decreasing hematocrit), the MY number an increase in plasma hemoglobin. Differences between LY and MY are an indication of subhemolytic events.
Pohl
M
M
Institut für Medizinische Physik und Biophysik, Universitätsklinikum Charité Humboldt-Universität zu Berlin.
Wendt
M O
MO
Pelzer
S
S
D000818:Animals; D001243:Assisted Circulation; D002417:Cattle; D019544:Equipment Failure Analysis; D006350:Heart Valve Prosthesis; D006452:Hemoglobinometry; D006461:Hemolysis / Q000502:physiology*; D006801:Humans; D008955:Models, Cardiovascular; D009996:Osmotic Fragility / Q000502:physiology*