title: Is there good simulation basic training for end-to-side vascular microanastomoses?
abstract: BACKGROUND
  Microvascular anastomosis is the cornerstone of free tissue transfers. Irrespective of the microsurgical technique that one seeks to integrate or improve, the time commitment in the laboratory is significant. After extensive previous training on several animal models, we sought to identify an animal model that circumvents the following issues: ethical rules, cost, time-consuming and expensive anesthesia, and surgical preparation of tissues required to access vessels before performing the microsurgical training, not to mention that laboratories are closed on weekends.
  
  
  METHODS
  Between January 2012 and April 2012, a total of 91 earthworms were used for 150 microsurgical training exercises to simulate vascular end-to-side microanastomosis. The training sessions were divided into ten periods of 7 days. Each training session included 15 simulations of end-to-side vascular microanastomoses: larger than 1.5 mm (n=5), between 1.0 and 1.5 mm (n=5), and smaller than 1.0 mm (n=5). A linear model with the main variables being the number of weeks (as a numerical covariate) and the size of the animal (as a factor) was used to determine the trend in time of anastomosis over subsequent weeks as well as the differences between the different size groups.
  
  
  RESULTS
  The linear model shows a significant trend (p<0.001) in time of anastomosis in the course of the training, as well as significant differences (p<0.001) between the groups of animals of different sizes. For microanastomoses larger than 1.5 mm, the mean anastomosis time decreased from 19.3±1.0 to 11.1±0.4 min between the first and last week of training (decrease of 42.5%). For training with smaller diameters, the results showed a decrease in execution time of 43.2% (diameter between 1.0 and 1.5 mm) and 40.9% (diameter<1.0 mm) between the first and last periods. The study demonstrates an improvement in the dexterity and speed of nodes execution.
  
  
  CONCLUSIONS
  The earthworm appears to be a reliable experimental model for microsurgical training of end-to-side microanastomoses. Its numerous advantages are discussed here and we predict training on earthworms will significantly grow and develop in the near future.
  
  
  METHODS
  This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .
authors: Department of Plastic and Hand Surgery, Inselspital Bern, University of Bern, Freiburgstrasse, Bern, Switzerland. franckleclere@yahoo.fr
authors: Franck Marie P
authors: FM
authors: Leclère
authors: Mario
authors: M
authors: Trelles
authors: Gregory A
authors: GA
authors: Lewbart
authors: Esther
authors: E
authors: Vögelin
mesh_terms: D000714:Anastomosis, Surgical / Q000193:education* / Q000379:methods; D000818:Animals; D016014:Linear Models; D008866:Microsurgery / Q000193:education* / Q000379:methods; D023421:Models, Animal; D009835:Oligochaeta; D061646:Operative Time; D013647:Task Performance and Analysis; D014656:Vascular Surgical Procedures / Q000193:education* / Q000379:methods