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Systematic research into device-induced red blood cell (RBC) damage beyond hemolysis, including correlations between hemolysis and RBC-derived extracellular vesicles, remains limited. This study investigated non-physiological shear stress-induced RBC damage and changes in related biochemical indicators under two blood pump clinical support conditions. Pressure heads of 100 and 350 mmHg, numerical simulation methods, and two in vitro loops were utilized to analyze the shear stress and changes in RBC morphology, hemolysis, biochemistry, metabolism, and oxidative stress. The blood pump created higher shear stress in the 350-mmHg condition than in the 100-mmHg condition. With prolonged blood pump operation, plasma-free hemoglobin and cholesterol increased, whereas plasma glucose and nitric oxide decreased in both loops. Notably, plasma iron and triglyceride concentrations increased only in the 350-mmHg condition. The RBC count and morphology, plasma lactic dehydrogenase, and oxidative stress across loops did not differ significantly. Plasma extracellular vesicles, including RBC-derived microparticles, increased significantly at 600 min in both loops. Hemolysis correlated with plasma triglyceride, cholesterol, glucose, and nitric oxide levels. Shear stress, but not oxidative stress, was the main cause of RBC damage. Hemolysis alone inadequately reflects overall blood pump-induced RBC damage, suggesting the need for additional biomarkers for comprehensive assessments. [ABSTRACT FROM AUTHOR]

A new analytical solution is developed to calculate the hydraulic emission uniformity (EUh) of horizontal tapered drip laterals. Our methodology builds upon normalizing the pressure head profiles along each segment of the lateral. Results indicated that the EUh remains fairly consistent regardless of the total lateral length if a fixed pressure head tolerance (δ) is assigned in the design process. Instead, the EUh is primarily influenced by the number of emitters on each segment, their diameter ratio, and the emitter exponent x. Employing tapered laterals for any given values of δ and x enhances energy conservation compared to using single diameter laterals. However, it may lead to a reduction in the EUh , particularly when the number of emitters in the smaller diameter segment is low relative to the total number of outlets. It was concluded that the coefficient of variation in emitter pressure heads CV and EUh exhibit a nonlinear behavior in the case of tapered laterals, whereas it has been previously established as linear for single diameter laterals. Interestingly, when applying the newly formulated relationships for EUh and CV while keeping the same diameter for both segments, the results align with those previously obtained for single diameter laterals. Validation of the proposed EUh model against the precise stepwise solution revealed a maximum absolute relative error of ≈1%. When excluding the fully laminar flow condition (x=1), relative errors typically remained below 0.5%. The proposed model could serve as a foundational framework for designing tapered laterals to achieve a targeted uniformity level in future studies. [ABSTRACT FROM AUTHOR]