No abstract

Although direct exposure to procedures in the operating theater environment, together with practice on laboratory animals, is still seen as the gold standard of teaching in microsurgery, practice on nonliving simulators is currently being validated as an important educational tool. We reviewed the widely used nonliving training models, together with currently accepted innovations, which are parts of curricula of training courses in microsurgery. Using the experience accumulated in training programs at the Centre for Simulation and Training in Surgery, we identified which particular skills can be reliably targeted by each nonliving tissue exercise. We were able to find five groups of nonliving training models: basic manipulation, knot-tying principles, completing the anastomosis, the real tissue experience, and training in virtual reality. The more abstract models might seem quite far from the real life experience, but they each closely address specific skills. It thus becomes convenient for the instructor to train these skills separately. This generates series of consistently favorable results once the skills are integrated into a more complex procedure. Focused exercises, once assembled in continuity, reconstruct the real life scenario. The training program can comprise a series of increasingly difficult exercises, which mirror the real life situations. Performance on nonliving models in each progressively more challenging exercise can be assessed via direct observation, assisted by clear and objective criteria. Finally, focused training will help both the transition to human surgery and replication of the favorable results to large series of subjects.

The aim of this study is to evaluate the amount of training needed by a trainee, with no background in microsurgery, in order to achieve proper skills for microvascular anastomosis. A protocol based on the rat femoral artery was established to provide a quantitative representation. Five inexperienced subjects started performing microvascular anastomosis. Patency was assessed at 30 min. The final assessment was performed at 2 weeks when rats were reoperated and the patency below the anastomosis was checked. The experiment was discontinued for one subject when he/she succeeded to have two series of four anastomosis with 100% patency at 2 weeks. The results were: 47.5% patency rate at 30 min and 7.5% at 2 weeks (series 1-2); 67.5 and 32.5% (3-4); 82.5 and 35% (5-6); 100 and 70% (7-8); 100 and 87.5% (9-10). Two trainees obtained 100% patency at 2 weeks after series 9-10. Other three needed two more series. There is a significant statistic difference (P < 0.01) between the results at 30 min and 2 weeks for the series (1-2, 3-4, 5-6, 7-8). The patency rate at 2 weeks reflects in a better way the microsurgical skills of a trainee. For long term functioning anastomosis, the training period needs an extension beyond that necessary for 100% patency at 30 min.

Standard magnification in microsurgery is accomplished with the operating microscope. Loupes are perceived by the microsurgical community as technically less safe. However, after several years of microscope-only microsurgery, most of our microvascular procedures are performed under loupes 3.5-4x. Considering our results using loupes-only microsurgery, which are comparable with those obtained when using the microscope, we suggest that loupe-aided microsurgery might represent a natural progression for the experienced microsurgeon. Microsurgical skills and experience outweigh the importance of the magnification factor. While the microscope is mandatory for replantations distal to the palmary arch, microneurosurgery, and supramicrosurgery, loupes should be used in so-called "macro-microsurgery." One may include in this category replantations down to the palmar arch and free flaps with vessels more than 1.5 mm, such as the latissimus, serratus, (para)scapular, fibula, radial forearm, rectus abdominis, dorsalis pedis, omentum, and jejunum. Before starting loupes-only microsurgery, intensive training under the microscope is crucial. Less magnification does not mean less quality.

New membranes based on chitosan and chitosan-hyaluronic acid containing new arginine derivatives with thiazolidine-4-one scaffold have been prepared using the ionic cross-linking method. The presence of the arginine derivatives with thiazolidine-4-one scaffold into the polymer matrix was proved by Fourier-transform infrared spectroscopy (FT-IR). The scanning electron microscopy (SEM) revealed a micro-porous structure that is an important characteristic for the treatment of burns, favoring the exudate absorption, the rate of colonization, the cell structure, and the angiogenesis process. The developed polymeric membranes also showed good swelling degree, improved hydrophilicity, and biocompatibility in terms of surface free energy components, which supports their application for tissue regeneration. Moreover, the chitosan-arginine derivatives (CS-6h, CS-6i) and chitosan-hyaluronic acid-arginine derivative (CS-HA-6h) membranes showed good healing effects on the burn wound model induced to rats. For these membranes a complete reepithelialization was observed after 15 days of the experiment, which supports a faster healing process.