Abstract
Formaldehyde has been traditionally used for embalming human cadavers for gross anatomy education and surgical skills training. However, exposure to formaldehyde negatively affects human health. This study aimed to assess the efficacy of reperfusing urea solution to a formalin-embalmed cadaver for surgical skills training and then investigate the cadaver’s tissue elasticity alteration after being soaked into the urea solution. Twelve surgeons evaluated the similarity of tissue characteristics between the cadaver (embalmed by formalin solution and reperfused by urea solution) and a living human body. Furthermore, the tissue formaldehyde content and mechanical properties of the formalin-fixated femoral skin and artery specimens with or without soaking into urea solution were measured. Results showed that the tactile assessment, skin incision, vessel ligation and suture, and decollement were better and more useful in the cadaver reperfused by urea solution than in the cadaver merely fixated by formalin solution. In the urea-reperfused cadaver, the volatilized, or tissue formaldehyde levels declined. The stiffness and Young’s modulus of the femoral skin and artery were also lower in the specimen than in the mere formalin-fixated specimen. In conclusion, reperfusion of urea solution to the formalin-fixated cadaver makes anatomical education and surgical skills training more efficient with fewer requirements for cadaver management.
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Acknowledgements
The authors sincerely thank those who donated their bodies to science so that anatomical research could be performed. Results from such research can potentially increase our overall knowledge, thereby improving patient care. Therefore, these donors and their families deserve our highest gratitude. The authors wish to thank Mr. Kazuto Arimura for his excellent secretarial and technical assistance. This work was supported by JSPS KAKENHI Grant Number 20K21735 (Grant-in-Aid for Challenging Exploratory Research). This work was also supported by JSPS KAKENHI Grant Number 16H01870 (Grant-in-Aid for Scientific Research (A)). The authors would like to thank Enago (www.enago.jp) for the English language review.
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Otsuka, S., Kawata, S., Nanizawa, E. et al. Efficacy of urea solution reperfusion to a formalin-embalmed cadaver for surgical skills training. Anat Sci Int 97, 264–272 (2022). https://doi.org/10.1007/s12565-022-00653-y
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DOI: https://doi.org/10.1007/s12565-022-00653-y