Quantitative Evaluation of Hemolysis Under Excessive Static and Repeated Negative Pressure During Blood Handling

The findings support the theoretical understanding that blood behaves as an incompressible fluid, equilibrating hydrostatic pressure across the red blood cell membrane to prevent rupture under static vacuum conditions. These results indicate that dynamic factors, such as shear stress and cavitation during rapid aspiration or pump operation, rather than static negative pressure, are the primary contributors to hemolysis. This study provides evidence-based guidance for safer blood collection practices and the design of medical devices, emphasizing control of dynamic stresses rather than avoidance of static negative pressure.