Endothelial Rbpj Is Required for Cerebellar Morphogenesis and Motor Control in the Early Postnatal Mouse Brain.

Intercellular influences are necessary for coordinated development and function of vascular and neural components in the brain. In the early postnatal period after birth, the mammalian cerebellum undergoes extensive morphogenesis - developing its characteristic lobules, organizing its diverse cell types into defined cellular layers, and establishing neural circuits that support cerebellar function, such as coordinated movement. In parallel, the cerebellar vasculature undergoes extensive postnatal growth and maturation, keeping pace with the expanding neural compartment. Endothelial deletion of Rbpj leads to neurovascular abnormalities in mice, including arteriovenous (AV) shunts that supplant capillaries and instead direct high-pressure/high-flow arterial blood directly to veins. Gross and histopathological cerebellar abnormalities, associated with these Rbpj-mediated brain AV malformations (AVMs), led to our hypothesis that early postnatal morphogenesis and lamination of cerebellum was perturbed in mice harboring endothelial Rbpj deficiency from birth. Here, we show that endothelial Rbpj-mutant mice developed enlarged vascular malformations on the cerebellar surface, by 2-week post-Rbpj deletion. In addition, outgrowth of cerebellar lobules was impaired through decreased cell proliferation, but not increased apoptosis, in the external granule layer. Molecular layer thickness was reduced, and the Purkinje layer was affected, by decreased Purkinje cell number, primary dendrite length, and dendritic arbor density. Endothelial deletion of Rbpj also led to impaired motor behaviors, consistent with abnormal cerebellar morphogenesis and lamination. Thus, our data suggest that Rbpj is required, in early postnatal vascular endothelium, to ensure proper cerebellar outgrowth, morphogenesis, and function in mice.

Staff Perspectives of Mass Casualty Incident Preparedness.

Introduction Mass casualty incidents (MCI) are low-frequency, high-risk events that disrupt the day-to-day operations of medical centers. Day-to-day protocols are insufficient for effectively managing MCI events, creating a need to develop and test MCI-specific protocols. The aim of this project was to utilize interviews to gain insight into staff experience and perspective on MCIs and their institution's response plans. Methods Staff members who participated in an MCI drill were asked semi-structured interview questions regarding their perspectives on their current priorities, the information needed to perform their role, and their greatest concerns about an MCI. This quality improvement (QI) project utilized a qualitative methodology to thematically organize the results of the staff responses. Results A total of 64 staff members with various levels of patient care experience were interviewed to reach thematic saturation. The use of staff interviews helped to identify the four primary themes that emerged, which were: 1) process, 2) supplies and resources, 3) communication, and 4) roles. Furthermore, each theme also included a number of subthemes. Conclusions This project demonstrated the importance of staff experiences related to MCI simulation training and preparedness, which may be useful for future training and emergency response planning. Additionally, the results may be helpful for other institutions when building a robust MCI simulation training program or designing an emergency response plan.

Simulation-based Training Curriculum for the Management of Vaginal Cuff Dehiscence and Evisceration.

Objective Vaginal cuff dehiscence with evisceration (VCDE) is a serious, life-threatening complication of hysterectomy. Due to the high volume of hysterectomies performed in the U.S each year, it is likely that a practitioner will encounter VCDE during their career. Due to its infrequent occurrence, residents receive little exposure to it during training. Delayed diagnosis of VCDE can impede proper management and lead to severe, long-term complications or death. Our goal was to provide an opportunity for resident physicians to identify VCDE and practice performing a reduction of prolapsed bowel and vaginal cuff repair through hands-on simulation in hopes that the simulation would improve the residents' confidence and knowledge in recognizing and managing future VCDE cases. Methods Obstetrics and Gynecology residents postgraduate year (PGY) 1-4 participated in this study (n=13). Before and after the simulated case, a knowledge test covering VCDE recognition and management and a confidence survey were given to the participants. A gynecologic mannequin was modified by placing simulated bowel into the abdominal cavity with a portion extending through a vaginal cuff and protruding from the vaginal introitus. For the simulation, a hemodynamically unstable patient presented with findings consistent with a VCDE. Once the decision to proceed to surgery was made, participants were transferred to a simulated operating room where they performed a reduction of prolapsed bowel and vaginal cuff closure either laparoscopically or vaginally on the mannequin. A debriefing session was held post-simulation to discuss management and thought processes, as well as reflect on their performance and discuss improvement strategies for future cases. Finally, the residents participated in a brief didactic lecture on education about the incidence, presentation, and management of VCDE. Results Analysis of the knowledge questionnaires showed the median score and interquartile range (IQR) pre- and post-simulation was 15(12-28) and 20(19-22) respectively, with a median score increase (and IQR) of 5(3.5-8.5) (p=0.001). The confidence score had pre- and post-simulation median scores (and IQRs) of 28(20-34.5) and 40(37.5-46) respectively, with a median score increase (and IQR) of 15(8-20.5) (p=0.001). Conclusions Our intervention improved residents' knowledge and confidence in recognizing VCDE, identifying the need for surgical management, and performing a reduction of prolapsed bowel and vaginal cuff repair.