A Simple, Reproducible and Low-cost Simulator for Teaching Surgical Techniques to Repair Obstetric Anal Sphincter Injuries

Abstract Objective To describe and evaluate the use of a simple, low-cost, and reproducible simulator for teaching the repair of obstetric anal sphincter injuries (OASIS). Methods Twenty resident doctors in obstetrics and gynecology and four obstetricians participated in the simulation. A fourth-degree tear model was created using lowcost materials (condom simulating the rectal mucosa, cotton tissue simulating the internal anal sphincter, and bovine meat simulating the external anal sphincter). The simulator was initially assembled with the aid of anatomical photos to study the anatomy and meaning of each component of the model. The laceration was created and repaired, using end-to-end or overlapping application techniques. Results The model cost less than R$ 10.00 and was assembled without difficulty, which improved the knowledge of the participants of anatomy and physiology. The sutures of the layers (rectal mucosa, internal sphincter, and external sphincter) were performed in keeping with the surgical technique. All participants were satisfied with the simulation and felt it improved their knowledge and skills. Between 3 and 6 months after the training, 7 participants witnessed severe lacerations in their practice and reported that the simulation was useful for surgical correction. Conclusion The use of a simulator for repair training in OASIS is affordable (low-cost and easy to perform). The simulation seems to improve the knowledge and surgical skills necessary to repair severe lacerations. Further systematized studies should be performed for evaluation.

**摘要**
目的：描述并评估一款简易、低成本且可重复使用的模拟器，用于产科肛门括约肌损伤（obstetric anal sphincter injuries, OASIS）修复术的教学培训。
方法：共计20名妇产科住院医师与4名产科医师参与本次模拟培训。采用低成本材料构建Ⅳ度会阴撕裂模型：以避孕套模拟直肠黏膜，棉织物模拟肛门内括约肌，牛肉模拟肛门外括约肌。初期借助解剖照片组装该模拟器，以熟悉模型各组件的解剖结构与意义。随后通过端端吻合或重叠缝合技术完成撕裂伤的造模与修复操作。
结果：该模型成本不足10巴西雷亚尔，组装过程无明显难度，可有效提升参与者对解剖与生理知识的掌握程度。参与者均能按照手术规范完成直肠黏膜、肛门内括约肌、肛门外括约肌三层缝合操作。所有参训人员均对本次模拟培训表示满意，并认为其有效提升了自身相关知识与操作技能。培训结束后3至6个月期间，有7名参与者在临床工作中遇到严重会阴撕裂病例，均反馈本次模拟培训对手术修复操作具有实际助益。
结论：用于产科肛门括约肌损伤修复培训的模拟器具备成本低廉、操作简便的优势。该模拟培训可有效提升严重会阴撕裂修复所需的解剖知识与手术技能，未来需开展系统化研究以进一步评估其应用价值。