The use of live animals for terminal surgical procedures in veterinary training programs has been decreasing in recent years owing to the ongoing trend toward reduction, refinement, and replacement of live animals for teaching and research purposes.1–4 Consequently, the use of cadavers and synthetic models for training purposes has been increasing.3–5 In both veterinary and human medicine, many commercial synthetic intestinal models have been developed to replace live animals and patients or cadavers in medical device studies, surgical simulations, and clinical training programs.6–11
Veterinary curricula and continuing education programs are increasingly embracing modern training modalities, such as simulations and the use of synthetic surgical models, because they improve student confidence and proficiency in a procedure before advancing to live animal experiences. These modalities also reduce the costs associated with live animal surgeries and decrease the number of live animals and cadavers required for students to gain proficiency, which is important because the acquisition of cadavers has become increasingly difficult at many institutions.12–14 Students enrolled in curricula that use simulated or synthetic models have more confidence and perform better when they transition to live animal training, compared with students enrolled in curricula that do not use such models.12,13 Additionally, synthetic tissue can be easily stored and more readily obtained for use in mass teaching exercises, compared with obtaining and preserving cadaveric tissue. Despite the many benefits associated with the use of synthetic models for surgical training, many factors unique to cadaveric tissue or live animals, such as tissue texture, hemorrhage, and mucosal eversion, are difficult or impossible to replicate with synthetic models.
In veterinary practice, surgical procedures of the gastrointestinal tract, such as enterotomy and intestinal resection and anastomosis, are commonly performed to alleviate obstructions and collect biopsy specimens. However, veterinary students have limited opportunities to perform or become proficient in gastrointestinal surgery on live animals during their training programs. Synthetic tissue represents an alternative training model and provides students the opportunity to practice surgical procedures, which is important given the difficulty and cost associated with obtaining live animals and cadavers for training purposes at many institutions. During enterotomy procedures on live animals, particularly those performed by novice surgeons, an intraoperative leak test is recommended to assess enteric suture line security and identify imperfections in closure technique with the goal of preventing postoperative leakage.15–18 It is unknown whether leak testing of enterotomy sites in synthetic intestinal tissue is as accurate as leak testing of enterotomy sites in canine cadaveric intestinal tissue for evaluation of suture line integrity. Additionally, to our knowledge, the intraluminal pressures capable of being sustained before and after enterotomy in synthetic intestinal tissue, compared with those in canine cadaveric tissues, have not been investigated.
The objective of the study reported here was to compare the intraluminal pressure at the time leakage was first observed during leak testing (ie, ILP) between synthetic and canine cadaveric intestinal segments that did and did not undergo a simple enterotomy. Our hypotheses were that the ILP would not differ significantly between synthetic and cadaveric intestinal segments that did not undergo enterotomy (ie, control segments), and that the ILP for cadaveric intestinal segments that underwent enterotomy would be greater than that for synthetic intestinal segments that underwent enterotomy.
No third-party funding or support was received in connection with this study or the writing and publication of this manuscript.
Drs. Case and Kim are patent holders (University of Florida No. 1607) of SynDaver Canine, the company that produced the synthetic intestinal tissue used in this study.
Initial leak pressure
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