Basic laparoscopic training using the Simbionix LAP Mentor: setting the standards in the novice group

BACKGROUND: Virtual reality devices are becoming the backbone for laparoscopic training in surgery. However, without knowledge of the achievable metrics of basic training within the trainee group, these simulators cannot be used effectively. Currently, no validated task metrics of the performance of larger trainee groups are available. STUDY DESIGN: From April 2004 to December 2009, we collated an extensive prospective database using the Simbionix LAP Mentor (Simbionix USA, Cleveland, Ohio) for basic laparoscopic training of novice surgeons. This database was used to determine benchmarks for basic skill exercises and procedural tasks that combine stimulus to improve and feasibility with acceptance of the training program and the goal to train for safe surgery. RESULTS: In all, 18,996 task performances of 286 novice trainees were analyzed. For the basic skill exercises, the total time for correct execution ranged between 45 seconds for basic skill 3 (eye-hand coordination) and 269 seconds for basic skill 9 (object placement). For the procedural tasks, the total time for correct execution ranged between 68 seconds for procedural task 1 (clipping and cutting) and 256 seconds for procedural task 3 (dissection). The total time to task completion depended mainly on right instrument path length with high correlation to left instrument path length. Learning curve analyses of the 4 procedural tasks demonstrated performance plateaus after 10-15 repetitions. Most complications occurred during the initial repetitions of the respective task. The best quartile of performances was chosen as peer group benchmark because it provides sufficient stimulus for improvement without discouraging trainees, thus enhancing adherence to the training program. The benchmark for safety and accuracy parameters was set at a predefined level of 95% correct execution. CONCLUSIONS: As experience with virtual reality (VR) training is growing, curricula must be based on benchmarks for efficient training derived from large trainee groups to optimize use of the still costly simulators. Safety parameters should be included in trainee assessment. We share a set of metrics that take into account both performance and feasibility for basic laparoscopic training of surgical novices using the Simbionix LAP Mentor

Transcutaneous vagal nerve simulation to reduce a systemic inflammatory response syndrome and the associated intestinal failure: study protocol of a prospective, two-armed, sham-controlled, double-blinded trial in healthy subjects (the NeuroSIRS-Study)

Purpose!#!Surgery initiates pro-inflammatory mediator cascades leading to a variably pronounced sterile inflammation (SIRS). SIRS is associated with intestinal paralysis and breakdown of intestinal barrier and might result in abdominal sepsis. Technological progress led to the development of a neurostimulator for transcutaneous auricular vagal nerve stimulation (taVNS), which is associated with a decline in inflammatory parameters and peristalsis improvement in rodents and healthy subjects via activation of the cholinergic anti-inflammatory pathway. Therefore, taVNS might be a strategy for SIRS prophylaxis.!##!Methods!#!The NeuroSIRS-Study is a prospective, randomized two-armed, sham-controlled, double-blind clinical trial. The study is registered at DRKS00016892 (09.07.2020). A controlled endotoxemia is used as a SIRS-mimicking model. 2 ng/kg bodyweight lipopolysaccharide (LPS) will be administered after taVNS or sham stimulation. The primary objective is a reduction of clinical symptoms of SIRS after taVNS compared to sham stimulation. Effects of taVNS on release of inflammatory cytokines, intestinal function, and vital parameters will be analyzed.!##!Discussion!#!TaVNS is well-tolerated, with little to no side effects. Despite not fully mimicking postoperative inflammation, LPS challenge is the most used experimental tool to imitate SIRS and offers standardization and reproducibility. The restriction to healthy male volunteers exerts a certain bias limiting generalizability to the surgical population. Still, this pilot study aims to give first insights into taVNS as a prophylactic treatment in postoperative inflammation to pave the way for further clinical trials in patients at risk for SIRS. This would have major implications for future therapeutic approaches

Orthotopic small bowel transplantation in rats

Small bowel transplantation has become an accepted clinical option for patients with short gut syndrome and failure of parenteral nutrition (irreversible intestinal failure). In specialized centers improved operative and managing strategies have led to excellent short- and intermediate term patient and graft survival while providing high quality of life (1,3). Unlike in the more common transplantation of other solid organs (i.e. heart, liver) many underlying mechanisms of graft function and immunologic alterations induced by intestinal transplantation are not entirely known(6,7). Episodes of acute rejection, sepsis and chronic graft failure are the main obstacles still contributing to less favorable long term outcome and hindering a more widespread employment of the procedure despite a growing number of patients on home parenteral nutrition who would potentially benefit from such a transplant. The small intestine contains a large number of passenger leucocytes commonly referred to as part of the gut associated lymphoid system (GALT) this being part of the reason for the high immunogenity of the intestinal graft. The presence and close proximity of many commensals and pathogens in the gut explains the severity of sepsis episodes once graft mucosal integrity is compromised (for example by rejection). To advance the field of intestinal- and multiorgan transplantation more data generated from reliable and feasible animal models is needed. The model provided herein combines both reliability and feasibility once established in a standardized manner and can provide valuable insight in the underlying complex molecular, cellular and functional mechanisms that are triggered by intestinal transplantation. We have successfully used and refined the described procedure over more than 5 years in our laboratory (8-11). The JoVE video-based format is especially useful to demonstrate the complex procedure and avoid initial pitfalls for groups planning to establish an orthotopic rodent model investigating intestinal transplantatio

HPV-associated anal lesions in HIV+ patients: long-term results regarding quality of life

Purpose!#!HIV infection and concomitant HPV-associated anal lesions may significantly impact on patients' quality of life (QoL), as they are predicted to have negative effects on health, psyche, and sexuality.!##!Material and methods!#!Fifty-two HIV+ patients with HPV-associated anal lesions were enrolled in a survey approach after undergoing routine proctologic assessment and therapy for HPV-associated anal lesions if indicated over a time span of 11 years (11/2004-11/2015). Therapy consisted of surgical ablation and topic treatment. QoL was analyzed using the SF-36 and the CECA questionnaires.!##!Results!#!Fifty-two of 67 patients (77.6%) were successfully contacted and 29/52 provided full information. The mean age was 43.8 ± 12.8 years. The median follow-up from treatment to answering of the questionnaire was 34 months. Twenty-one percent (6/29) of the patients reported suffering from recurrence of condyloma acuminata, three patients from anal dysplasia (10.3%). In the SF-36, HIV+ patients did not rate their QoL as significantly different over all items after successful treatment of HPV-associated anal lesions. In the CECA questionnaire, patients with persisting HPV-associated anal lesions reported significantly higher emotional stress levels and disturbance of everyday life compared to patients who had successful treatment (71.9/100 ± 18.7 vs. 40.00/100 ± 27.4, p = 0.004). Importantly, the sexuality of patients with anal lesions was significantly impaired (59.8/100 ± 30.8 vs. 27.5/100 ± 12.2, p = 0.032).!##!Conclusion!#!HPV-associated anal lesions impact significantly negative on QoL in HIV+ patients. Successful treatment of HPV-associated anal lesions in HIV+ patients improved QoL. Specific questionnaires, such as CECA, seem to be more adequate than the SF-36 in this setting

Access to a simulator is not enough: the benefits of virtual reality training based on peer-group-derived benchmarks--a randomized controlled trial.

BACKGROUND: Virtual reality (VR) simulators are widely used to familiarize surgical novices with laparoscopy, but VR training methods differ in efficacy. In the present trial, self-controlled basic VR training (SC-training) was tested against training based on peer-group-derived benchmarks (PGD-training). METHODS: First, novice laparoscopic residents were randomized into a SC group (n = 34), and a group using PGD-benchmarks (n = 34) for basic laparoscopic training. After completing basic training, both groups performed 60 VR laparoscopic cholecystectomies for performance analysis. Primary endpoints were simulator metrics; secondary endpoints were program adherence, trainee motivation, and training efficacy. RESULTS: Altogether, 66 residents completed basic training, and 3,837 of 3,960 (96.8 %) cholecystectomies were available for analysis. Course adherence was good, with only two dropouts, both in the SC-group. The PGD-group spent more time and repetitions in basic training until the benchmarks were reached and subsequently showed better performance in the readout cholecystectomies: Median time (gallbladder extraction) showed significant differences of 520 s (IQR 354-738 s) in SC-training versus 390 s (IQR 278-536 s) in the PGD-group (p < 0.001) and 215 s (IQR 175-276 s) in experts, respectively. Path length of the right instrument also showed significant differences, again with the PGD-training group being more efficient. CONCLUSIONS: Basic VR laparoscopic training based on PGD benchmarks with external assessment is superior to SC training, resulting in higher trainee motivation and better performance in simulated laparoscopic cholecystectomies. We recommend such a basic course based on PGD benchmarks before advancing to more elaborate VR training

Experimental groups and study design.

<p>Experimental groups and study design.</p

ACR-related gene expression in graft muscularis.

<p>The first time point at four days after allogenic ITX showed a significant downregulation of both TNFα and IL-10 by HLA-G treatment (Mann-Whitney U test p<0.05). At seven days after allogenic ITX, TNFα expression remained significantly reduced by HLA-G treatment.</p

Gating strategy and overview of T_reg (CD4⁺/CD25⁺/FoxP3⁺) isolated from gMLN with and without HLA-G treatment after allogenic intestinal transplantation.

<p>(A) Gating strategy and representative result for Treg analysis. (B) Overview of classical Treg (CD4⁺/CD25⁺/FoxP3⁺ Treg), isolated from gMLN. A tendency to higher abundance in HLA-G treated animals, without reaching statistical significance (Mann-Whitney U test p>0.05), was observed.</p

Gating strategy and overview of CD4⁺ and CD8⁺ T-cells isolated from gMLN with and without HLA-G treatment after allogenic intestinal transplantation.

<p>A) Representative gating strategy for recipient(LEW)-derived (MHC I/RT1.Ac-negative), CD45⁺ and CD8⁺ and likewise, CD4⁺ T-cells. Percentages of CD4⁺ and CD8⁺ are given as percentages of CD45⁺ parent population, shown is a representative result for CD8⁺ with and without HLA-G treatment at POD 7. (B) Overview of CD4⁺ and CD8⁺ T-cells with and without HLA-G treatment at both timepoints. A significant increase in CD8⁺ T-cells in the CTL groups is shown without treatment, as well as a significant reduction of this CD8⁺ T-cell population at day seven with HLA-G treatment.</p