METHODS: We adopted multiple adaptive strategies including changes to stratification of surgeries, out-patient services by urgency and hospital alert status, policy writing involving multidisciplinary teams, and redeployment of manpower. Modifications were made to teaching activities and skills training to observe social distancing and mitigate reduced operative learning opportunities. Roles of academic staff were expanded to include non-surgical duties.
RESULTS: The planned strategies and changes to pre COVID-19 practices were successful in ensuring minimal disruption to the delivery of essential paediatric surgical services and training. Despite the lack of established guidelines and literature outlining strategies to address the impact of this pandemic on surgical services, most of the initial measures employed were consistent with that of other surgical centres.
CONCLUSION: Changes to delivery of surgical services and surgical training warrant a holistic approach and a constant re-evaluation of practices with emergence of new experiences and guidelines.
STATEMENT OF SIGNIFICANCE: In this study we have tissue engineered a novel cell free tubular collagen based scaffold and used it as a urethral graft in a rabbit model. The novelty of our technique is that the tube can be sutured. Testing showed better burst pressures and the grafts could then be successfully implanted after a urethral excision. This long term study demonstrated excellent biocompatibility of the 2cm graft and gradual regeneration with time, challenging the current literature. Finally, the main impact is that we describe an off-the-shelf and cost-effective product with comparable surgical outcome to the cellular grafts.
STATEMENT OF SIGNIFICANCE: Urinary incontinence is involuntary urine leakage, resulting from a deficient function of the sphincter muscle complex. Yet there is no functional cure for this devastating condition using current treatment options. Applied physical and surgical therapies have limited success. In this study, a novel bioactive injectable bulking agent, triggering new muscle regeneration at the injection site, has been evaluated. This injectable consists of cross-linked collagen and fibrin micro-beads, functionalized with bound insulin-like growth factor-1 (α2PI1-8-MMP-IGF-1). These bioactive fibrin micro-beads induced human smooth muscle cell migration in vitro. Thus, this injectable bulking agent is apt to be a good candidate for regeneration of urethral sphincter muscle, ensuring a long-lasting treatment for urinary incontinence.
MATERIALS AND METHODS: Acellular meshes were engineered using liquid collagen. They underwent in vitro, mechanical and bench testing by surgeons. Sixty-nine male New Zealand rabbits were used to refine the design. The final prototype based on the TissueSpan patented technology was then implanted again in a 2 cm long urethral defect in 9 rabbits and in a 4 cm long defect in 6 dogs.
RESULTS: The TissueSpan technology platform allows for the manufacturing of tubular and rectangular meshes in different diameters and thicknesses. The tubular mesh acted as physical conduit to gap the urethral defect with a patent urethra demonstrated after 1month in both animal models. The mesh was absorbed within 1-3months. Spontaneous urothelial coverage of the mesh and smooth muscle cell migration into the surgical area was demonstrated even in a 4 cm long urethral defect. A first in man clinical trial was subsequently initiated.
CONCLUSION: The acellular mesh may have the potential to be an off-the-shelf product for substitution urethroplasty. Its mechanical properties allow surgeons to easily create a physical conduit while its material properties favor tissue remodeling. A large-scale clinical trial is still required to further confirm the safety, performance, and patient benefit of this new medical device.