The importance of expert feedback during endovascular simulator training

ObjectivesComplex endovascular skills are difficult to obtain in the clinical environment. Virtual reality (VR) simulator training is a valuable addition to current training curricula, but is there a benefit in the absence of expert trainers?MethodsEighteen endovascular novices performed a renal artery angioplasty/stenting (RAS) on the Vascular Interventional Surgical Trainer simulator. They were randomized into three groups: Group A (n = 6, control), no performance feedback; Group B (n = 6, nonexpert feedback), feedback after every procedure from a nonexpert facilitator; and Group C (n = 6, expert feedback), feedback after every procedure from a consultant vascular surgeon. Each trainee completed RAS six times. Simulator-measured performance metrics included procedural and fluoroscopy time, contrast volume, accuracy of balloon placement, and handling errors. Clinical errors were also measured by blinded video assessment. Data were analyzed using SPSS version 15.ResultsA clear learning curve was observed across the six trials. There were no significant differences between the three groups for the general performance metrics, but Group C made fewer errors than Groups A (P = .009) or B (P = .004). Video-based error assessment showed that Groups B and C performed better than Group A (P = .002 and P = .000, respectively).ConclusionVR simulator training for novices can significantly improve general performance in the absence of expert trainers. Procedure-specific qualitative metrics are improved with expert feedback, but nonexpert facilitators can also enhance the quality of training and may represent a valuable alternative to expert clinical faculty

Memory Th1 Cells Are Protective in Invasive <i>Staphylococcus aureus</i> Infection

<div><p>Mechanisms of protective immunity to <i>Staphylococcus aureus</i> infection in humans remain elusive. While the importance of cellular immunity has been shown in mice, T cell responses in humans have not been characterised. Using a murine model of recurrent <i>S</i>. <i>aureus</i> peritonitis, we demonstrated that prior exposure to <i>S</i>. <i>aureus</i> enhanced IFNγ responses upon subsequent infection, while adoptive transfer of <i>S</i>. <i>aureus</i> antigen-specific Th1 cells was protective in naïve mice. Translating these findings, we found that <i>S</i>. <i>aureus</i> antigen-specific Th1 cells were also significantly expanded during human <i>S</i>. <i>aureus</i> bloodstream infection (BSI). These Th1 cells were CD45RO⁺, indicative of a memory phenotype. Thus, exposure to <i>S</i>. <i>aureus</i> induces memory Th1 cells in mice and humans, identifying Th1 cells as potential <i>S</i>. <i>aureus</i> vaccine targets. Consequently, we developed a model vaccine comprising staphylococcal clumping factor A, which we demonstrate to be an effective human T cell antigen, combined with the Th1-driving adjuvant CpG. This novel Th1-inducing vaccine conferred significant protection during <i>S</i>. <i>aureus</i> infection in mice. This study notably advances our understanding of <i>S</i>. <i>aureus</i> cellular immunity, and demonstrates for the first time that a correlate of <i>S</i>. <i>aureus</i> protective immunity identified in mice may be relevant in humans.</p></div