Computational analysis of pediatric ventricular assist device implantation to decrease cerebral particulate embolization

Stroke is the most devastating complication after ventricular assist device (VAD) implantation with a 19% incidence and 65% mortality in the pediatric population. Current pediatric VAD technology and anticoagulation strategies alone are suboptimal. VAD implantation assisted by computational methods (CFD) may contribute reducing the risk of cerebral embolization. Representative three-dimensional aortic arch models of an infant and a child were generated. An 8 mm VAD outflow-graft (VAD-OG) anastomosed to the aorta was rendered and CFD was applied to study blood flow patterns. Particle tracks, originating in the VAD, were computed with a Lagrangian phase model and the percentage of particles entering the cerebral vessels was calculated. Eight implantation configurations (infant = 5 and child = 3) and 5 particle sizes (0.5, 1, 2, 3, and 4 mm) were considered. For the infant model, percentage of particles entering the cerebral vessels ranged from 15% for a VAD-OG anastomosed at 90° to the aorta, to 31% for 30° VAD-OG anastomosis (overall percentages: X² = 10,852, p < 0.0001). For the child model, cerebral embolization ranged from 9% for the 30° VAD-OG anastomosis to 15% for the 60° anastomosis (overall percentages: χ² = 10,323, p < 0.0001). Using detailed CFD calculations, we demonstrate that the risk of stroke depends significantly on the VAD implantation geometry. In turn, the risk probably depends on patient-specific anatomy. CFD can be used to optimize VAD implantation geometry to minimize stroke risk.     

Urine proteomic profiling to identify biomarkers of steroid resistance in pediatric nephrotic syndrome

Long-term prognosis for children with nephrotic syndrome (NS) is directly related to steroid responsiveness. There are currently no diagnostic tests that accurately predict steroid responsiveness in pediatric NS. The initial prolonged course of daily, high-dose corticosteroid therapy thus serves both as a diagnostic and therapeutic maneuver. Urine proteomics is emerging as a potentially rich source of noninvasive biomarkers of drug responsiveness in NS. In this article, we discuss some of the initial studies of the urinary proteome in NS as well as ongoing and future challenges, define the normal urinary proteome and address the overwhelming abundance of urinary albumin and its impact on biomarker discovery.     

A Hematogenous Route for Medulloblastoma Leptomeningeal Metastases

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Assistance dog placement in the pediatric population: Benefits,risks, and recommendations for future application

Abstract

Assistance animals have long been recognized for their value in enhancing the lives of adults with disabilities by increasing the physical independence, confidence, and social lives of their handlers. Recently, this concept has been applied to the growing population of children with physical disabilities and developmental impairments, though the benefits and risks of these placements have not been thoroughly assessed. Our study used interviews to evaluate the outcome of placing assistance dogs in the pediatric population, looking specifically at the unique advantages and disadvantages of this application of the human–animal bond. We administered a structured interview assessing risks and benefits of assistance dog relationships to 17 families with a child under 18 years who graduated from a single provider (NEADS) over a five-year time period. Benefits were found in 88% of families, and were overwhelmingly social and cognitive, with additional physical and medical benefits for the pediatric client. However, risks, including behavioral, financial, and time/cost issues were significant, becoming a burden in 53% of families. Perhaps more than with adult placements, we found that it was of prime importance to understand the assistance animal in the context of the family, rather than just in relation to the individual with a disability. It is hoped that results of this and future studies will enhance the welfare of both client and assistance animal, as well as the overall success of this unique human–animal relationship.