Transpulmonary pressure can be estimated using esophageal balloon (EB) catheters, which come in a variety of manufacturing configurations. We assessed the performance of novel polyurethane EB designs, Aspisafe NG and NG+, against existing alternatives. We created a biomechanical model of the chest cavity using a plastic chamber and an ex-vivo porcine esophagus.
View Article and Find Full Text PDFObjective: Pulsatile-flow veno-arterial extracorporeal membrane oxygenation (V-A ECMO) has shown encouraging results for microcirculation resuscitation and left ventricle unloading in patients with refractory cardiogenic shock. We aimed to comprehensively assess different V-A ECMO parameters and their contribution to hemodynamic energy production and transfer through the device circuit.
Methods: We used the i-cor® ECMO circuit, which composed of Deltastream DP3 diagonal pump and i-cor® console (Xenios AG), the Hilite 7000 membrane oxygenator (Xenios AG), venous and arterial tubing and a 1 L soft venous pseudo-patient reservoir.
Due to the high treatment costs associated with durable ventricular assist devices, an intra-ventricular balloon pump (IVBP) was developed to provide low-cost, short-term support for patients suffering from severe heart failure. It is imperative that intraventricular flow dynamics are evaluated with an IVBP to ensure stagnation points, and potential regions for thrombus formation, are avoided. This study used particle image velocimetry to evaluate flow patterns within the left ventricle of a simulated severe heart failure patient with IVBP support to assess left ventricle pulsatility as an indicator of the likelihood of flow stasis.
View Article and Find Full Text PDFCell exclusion in spiral groove bearing (SGB) excludes red blood cells from high shear regions in the bearing gaps and potentially reduce haemolysis in rotary blood pumps. However, this mechanobiological phenomenon has been observed in ultra-low blood haematocrit only, whether it can mitigate blood damage in a clinically-relevant blood haematocrit remains unknown. This study examined whether cell exclusion in a SGB alters haemolysis and/or high-molecular-weight von Willebrand factor (HMW vWF) multimer degradation.
View Article and Find Full Text PDFPurpose: Rotary blood pumps (RBPs) employed as ventricular assist devices are developed to support the ventricles of patients suffering from heart failure. Computational Fluid Dynamics (CFD) is frequently used to predict the performance and haemocompatibility of these pumps during development, however different simulation techniques employed by various research groups result in inconsistent predictions. This inconsistency is further compounded by the lack of standardised model validation, thus it is difficult to determine which simulation techniques are accurate.
View Article and Find Full Text PDFDesign methods for large industrial pumps are well developed, but they cannot be relied upon when designing specialised miniature pumps, due to scaling issues. Therefore, the design and development phase of small pumps demand numerous experimental tests to ensure a viable prototype. Of initial interest is hydraulic design in the form of pump performance and efficiency curves.
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