Clot embolization studies and computational framework for embolization in a canonical tube model

Abstract Despite recent advances in the development of computational methods of modeling thrombosis, relatively little effort has been made in developing methods of modeling blood clot embolization. Such a model would provide substantially greater understanding of the mechanics of embolization, as in-vitro and in-vivo characterization of embolization is difficult. Here, a method of computationally simulating embolization is developed. Experiments are performed of blood clots formed in a polycarbonate tube, where phosphate-buffered saline is run through the tube at increasing flow rates until the clot embolizes. The experiments revealed embolization can be initiated by leading edge and trailing edge detachment or by non-uniform detachment. Stress-relaxation experiments are also performed to establish values of constitutive parameters for subsequent simulations. The embolization in the tube is reproduced in silico using a multiphase volume-of-fluid approach, where the clot is modeled as viscoelastic. By varying the constitutive parameters at the wall, embolization can be reproduced in-silico at varying flow rates, and a range of constitutive parameters fitting the experiments is reported. Here, the leading edge embolization is simulated at flow rates consistent with the experiments demonstrating excellent agreement in this specific behavior

Access to best-evidenced mental health support for care-experienced young people: Learnings from the implementation of cognitive therapy for PTSD

Objectives: Rates of PTSD are up to 12 times higher in care-experienced young people (CEYP) compared to their peers. Trauma-focused CBTs (tf-CBT) are the best-evidenced treatment for youth with PTSD, yet, in practice, CEYP often struggle to access this treatment. We worked alongside services to understand barriers and facilitators of the implementation of cognitive therapy for PTSD (a type of tf-CBT) to CEYP. Design: This was an active, open implementation trial. Methods: We recruited 28 mental health teams across England, including general CAMHS, targeted CAMHS for CEYP and social care-based teams. From these teams, participants were 243 mental health professionals, from a wide variety of professional backgrounds. Following recruitment/intervention training, teams participated in rolling three monthly focus groups and individual interviews, to understand what helped and hindered implementation. Data were analysed using a framework analysis conducted using CFIR 2.0. Results: Almost half of the teams were able to implement, but only approximately one quarter with CEYP, specifically. Universal barriers that were discussed by almost all teams particularly highlighted service structures and poor resourcing as major barriers to delivery to CEYP, as well as the complexities of the young person and their network. Unique factors that differentiated teams who did and did not implement included commissioning practices, the culture of the team, leadership engagement and style, and the development of supervision structures. Conclusions: Findings offer key considerations for mental health teams, service leads, commissioners and policy-makers to enhance delivery of best-evidenced mental health treatments like CT-PTSD, for CEYP