P36: Filling the Gap: Developing the Penn State University Child Pump

Abstract

Study: Despite the need for suitable Mechanical Circulatory Support (MCS) for pediatric patients between 10 and 30 kg, there are currently no long-term implantable devices for this patient cohort. In order to address this need, we are developing the Penn State Child Pump, a continuous flow ventricular assist device (cf-VAD) that will remove the risks of device size mismatch and running at suboptimal operating conditions. Methods: A prototype PSU Child Pump was manufactured based on our experiences with adult cf-LVADs and cf-RVADs. The pump size was tailored to the average chest size of the target pediatric patient population (Figure 1A). In-vitro hemolysis was evaluated under three conditions on our small volume mock circulatory loop with bovine blood (Figure 1B): 1) 8300 RPM, ΔP = 60 mmHg, 3.5 LPM; 2) 8200 RPM, ΔP = 20 mmHg, 5.1 LPM; 3) 8400 RPM, ΔP = 70 mmHg, 3.2 LPM. Results: The initial design of the device has an approximate 38% reduction in size compared to our adult cf-VAD. A mock fit study was conducted using a 3D printed model of a 19 kg patient’s thoracic cavity to compare the size of the PSU Child Pump to the HVAD (Medtronic, Minneapolis, MN) (Figure 1A). In-vitro testing revealed the hemolysis levels at conditions 1, 2, and 3 were 0.037 mg/dL, 0.022 mg/dL, and 0.021 mg/dL, respectively (Figure 1C). Conclusions: The PSU Child Pump prototype was constructed and evaluated, yielding initial results indicating promising hemocompatibility under the given testing conditions. Using a computational fluid dynamics-based optimization platform, the PSU Child Pump will be optimized to meet maximum physiological requirements while minimizing the potential for thrombus formation, plasma-free hemoglobin levels, and degradation of von Willebrand factor. The in-silico optimization results will be validated through a series of 30-day in-vivo studies in sheep.