Showing papers by "Rajesh Aggarwal published in 2005"

Consensus guidelines for validation of virtual reality surgical simulators

Abstract: The Work Group for Evaluation and Implementation of Simulators and Skills Training Programmes is a newly formed sub-group of the European Association of Endoscopic Surgeons (EAES). This work group undertook a review of validation evidence for surgical simulators and the resulting consensus is presented in this article. Using clinical guidelines criteria, the evidence for validation for six different simulators was rated and subsequently translated to a level of recommendation for each system. The simulators could be divided into two basic types; systems for laparoscopic general surgery and flexible gastrointestinal endoscopy. Selection of simulators for inclusion in this consensus was based on their availability and relatively widespread usage as of July 2004. Whilst level 2 recommendations were achieved for a few systems, it was clear that there was an overall lack of published validation studies with rigorous experimental methodology. Since the consensus meeting, there have been a number of new articles, system upgrades and new devices available. The work group intends to update these consensus guidelines on a regular basis, with the resulting article available on the EAES website (http://www.eaes-eur.org ).

Synchronized Video and Motion Analysis for the Assessment of Procedures in the Operating Theater

Abstract: Hypothesis: Objective assessment of surgical skill has recently been shown to be possible through the use of dexterity-based and video analysis systems. The aim of this study was to synchronize these 2 modalities to produce a comprehensive surgical assessment tool. Design: The Imperial College Surgical Assessment Device is a dexterity-based motion analysis device that has been developed in the Department of Surgical Oncology and Technology by the Surgical Computing and Imaging Research Group. Further advances to this system have been made to enable synchronized acquisition of hand kinematics and video from real procedures, and their concurrent analysis. To test the feasibility of the system, 10 laparoscopic cholecystectomies performed by 5 different surgeons on consenting patients were recorded. Analysis focused on the entire procedure and also on specific parts of the operation such as the clipping and cutting of the cystic duct and artery. Results: Dexterity analysis was performed using the objective measures of time, path length, number of movements, velocities, and trajectories. Comparative analysis of a surgeon’s dexterity was carried out on the whole procedureandbyusingthesynchronizedzoomfacilityinthe software. Kinematic signals revealed rapid changes in velocity caused by alternating between different instruments or occurring after complications such as bleeding. Conclusion: This new motion analysis system has been shown to be an effective tool for the comprehensive assessment of operative procedures.

Objective assessment of technical skills in cardiac surgery

Abstract: Objective: Reduced training time combined with no rigorous assessment for technical skills makes it difficult for trainees to monitor their competence. We have developed an objective bench-top assessment of technical skills at a level commensurate with a junior registrar in cardiac surgery. Methods: Forty cardiothoracic surgeons were recruited for the study, consisting of 12 junior trainees (year 1‐3), 15 senior trainees (year 4‐6) and 13 consultants. The assessment consisted of four key tasks on standardised bench-top models: aortic root cannulation, vein-graft to aorta anastomosis, vein-graft to Left Anterior Descending (LAD) anastomosis and femoral triangle dissection. An expert surgeon was present at each station to provide passive assistance and rate performance on a validated global rating scale giving rise to a total possible score of 40. Three expert surgeons repeated the ratings retrospectively, using blinded video recordings. Data analysis employed non-parametric tests. Results: Both live and video scores differentiated significantly between performances of all groups of surgeons for all four stations (P!0.01) (median live and video score for LAD; Junior 19,17; Senior 29,22; Consultant 36,28). Correlations between live and blinded rating were high (rZ0.67‐0.84; P!0.001) as was inter-rater reliability between the three expert video raters (aZ0.81). Conclusions: The use of bench-top tasks to differentiate between cardiac surgeons of differing technical abilities has been validated for the first time. Furthermore, it is unnecessary to perform post-hoc video rating to obtain objective data. These measures can provide formative feedback for surgeons-in-training and lead to the development of a competency-based technical skills curriculum. Q 2005 Elsevier B.V. All rights reserved.

Compression anastomoses revisited.

Abstract: E I d s f I m e or more than 2 centuries, surgeons have attempted to roduce a tool that can satisfy the requisites for an ideal astrointestinal anastomosis. There is general consensus bout the importance of a good blood supply, accurate erosal apposition with no tension on the anastomotic ine, and an uncompromised lumen with a water-tight eal. A device to produce these characteristics in a stanardized and automated manner may enable the sureon to perform a competent anastomosis both quickly nd cost-effectively. The development of suture-based anastomoses was opularized by numerous studies that sought to modify riginal techniques, principally in terms of suture mateials, bowel wall layers, and the importance of inversion. ut it was soon noted that “sutures placed by hand uniormly evoke an inflammatory response because draging the thread through the bowel wall injures tissue.” he use of nonabsorbable sutures additionally exaggertes the inflammatory response, leading to a fall in nastomotic strength and a propensity to leak. The oreign body placed within the bowel wall has also been mplicated in the induction of surgical infection by proiding a track through which bacteria may traverse. umor growth studies have also shown that tumor cells re adherent to suture material, particularly braided suures, and may increase the risk of anastomotic ecurrence. Surgical stapling devices were first introduced in 1908 y Hultl in a presentation at the second congress of the ungarian Surgical Society. In 1966, Ravitch and coleagues reported experimental studies of closing gasric, duodenal, and intestinal stumps with two rows of taggered staples, forming an everted staple line that ealed with remarkably little inflammatory response. he group concluded that the everted anastomosis

Assessment of psychomotor skills acquisition during laparoscopic cholecystectomy courses

Abstract: Background Standardized short courses in laparoscopic cholecystectomy aim to teach laparoscopic skills to surgical trainees, although end-of-course assessments of performance remain subjective. The current study aims to objectively assess psychomotor skills acquisition of trainees attending laparoscopic cholecystectomy courses. Methods Thirty-seven junior surgical trainees had their laparoscopic skills assessed before and after attending 1 of 3 separate 2-day courses (A, B, and C), all with identical format. Assessments were comprised of a standardized simulated laparoscopic task, with performance measured using a valid electromagnetic hand-motion tracking device. Results Overall, trainees made significant improvements in path length ( P = .006), number of movements ( P P Discussion Objective validated methods can be used to assess learning of psychomotor skills on courses. In addition to providing participants with an insight into their skills, these data can be used to demonstrate course efficacy.

Laparoscopic task recognition using Hidden Markov Models.

Abstract: Surgical skills assessment has been paid increased attention over the last few years. Stochastic models such as Hidden Markov Models have recently been adapted to surgery to discriminate levels of expertise. Based on our previous work combining synchronized video and motion analysis we present preliminary results of a HMM laparoscopic task recognizer which aims to model hand manipulations and to identify and recognize simple surgical tasks.

Skills training in telerobotic surgery.

Abstract: Surgical robots have the potential to expand the repertoire of minimally invasive surgery resulting in more patients benefiting from lower operative morbidity and shorter hospital stays. However, in a similar manner to all new surgical interventions it necessary to explore the learning curves of practitioners as they adopt this new technology to enable optimisation of future training programs. Only when the standard of practice is firmly established, should the proliferation of robotic practitioners be encouraged thus ensuring patient safety is not compromised.

Organising a surgical skills centre.

Abstract: The aim of this paper is to define a strategy for the development and organisation of a surgical skills centre. The areas of interest can be divided into decisions about who, what and where to teach, the importance of an approach which is competency-based, definition of staff to run the centre, and also the use of the centre for the purposes of assessment, as well as training. The efficient delivery of this service will be augmented by adopting a multi-disciplinary and multi-professional approach, and must also be malleable enough to adopt future developments, such as web-based learning. Simulation is now the preferred mode of practice for commencement of surgical training. Surgical skills centres must be able to supply users with tools in a suitably designed environment, which enables them to move along a curriculum which is delivered in a competency-based manner.

Desarrollo de un programa de formación quirúrgica

Abstract: Cir Esp 2005;77(1):1-2 1 Los cambios actuales en la asistencia sanitaria y su efecto sobre la formación de los médicos residentes están teniendo una aceptación muy variable. En lo que se refiere concretamente a las especialidades quirúrgicas, la legislación relativa a los horarios de trabajo asistencial, las iniciativas adoptadas en relación con las listas de espera y las valoraciones de los niveles de calidad de los centros ambulatorios y los hospitales han dado lugar a conflictos entre las prioridades asistenciales y las formativas. En la actualidad no es aceptable ni económicamente eficiente la formación de cirujanos mediante el antiguo modelo del “aprendiz”. Para mantener la dedicación asistencial de estos residentes y reconfigurar los servicios hospitalarios es necesario desarrollar una nueva solución integrada. El objetivo prioritario de un programa de residentes en cirugía es la formación de profesionales competentes que tengan las capacidades cognoscitivas, técnicas y personales necesarias para resolver las necesidades de la sociedad en su ámbito de competencia. Las limitaciones impuestas por el trabajo asistencial y la posible reducción de las oportunidades de formación en hasta un 50% han hecho que muchos cirujanos empiecen a considerar que este objetivo puede no ser alcanzable. Además, los cirujanos nos enfrentamos a presiones, tanto sociales como políticas, cada vez mayores para alcanzar niveles predefinidos de competencia antes de que se nos autorice a ejercer de manera independiente. El establecimiento de los horarios de formación durante los programas de residencia puede resolver los problemas relativos a la dedicación asistencial. Así, la formación tiene lugar según un currículo predefinido en el que se abordan todos los aspectos que los residentes deben aprender. La evaluación de la habilidad de los residentes se lleva a cabo a intervalos regulares y mediante el uso de herramientas de medición fiables y validadas. La superación de las pruebas de evaluación permite al residente pasar a la siguiente fase del programa, mientras que, si no supera uno de los escalones de la evaluación, deberá repetir todo el bloque formativo correspondiente. De esta manera, los cirujanos pueden aprender las técnicas quirúrgicas mediante un abordaje lógico y escalonado, lo que les permite el desarrollo de un currículo basado en la competencia profesional. En cada fase del currículo, la formación se debe iniciar en el laboratorio mediante el uso de herramientas como los modelos de material sintético, los tejidos animales y la simulación mediante realidad virtual. Estas tareas deben ser supervisadas por el personal facultativo adecuado, como los coordinadores de residentes, y se deben establecer sesiones clínicas dirigidas hacia cada grupo específico de residentes. La realización de estas sesiones se debe compaginar con las teorías educativas del aprendizaje, no solamente con los horarios de los cirujanos de plantilla. Además, deben constituir una parte integral y obligatoria del programa de los residentes en formación. Los residentes más recientes deberían asistir posiblemente una vez a la semana, mientras que los más veteranos deberían completar un número menor de sesiones, cuyo objetivo estaría centrado en aspectos más concretos. Las sesiones se deberían complementar con la formación adecuada en el quirófano, preferiblemente con el mismo coordinador de residentes que supervisa el trabajo en el laboratorio. Es importante establecer una separación clara entre las horas de quirófano dedicadas a la asistencia y las dedicadas a la formación, con objeto de conseguir el equilibrio entre las necesidades formativas y asistenciales. El currículo basado en la competencia profesional depende del uso de herramientas válidas y fiables que permitan efectuar evaluaciones subjetivas del rendimiento quirúrgico; sin embargo, hasta el momento sólo se han utilizado métodos que valoran exclusivamente la habilidad técnica. En la bibliografía quirúrgica se han validado con detalle diversos sistemas de determinación de la habilidad quirúrgica basados en vídeo. Sin embargo, en la actualidad no se utiliza ninguno de estos sistemas en la Editorial