Surgical guide including innovative techniques for orthotopic liver transplantation in the rat: Key techniques and pitfalls in whole and split liver grafts

Background. Although the techniques of orthotopic liver transplantation (OLT) and split OLT (S-OLT) have been well documented in the rat by established microsurgeons, the surgical skills required for this model limits its use by some investigators. Furthermore, alternative artificial OLT/S-OLT models are of limited use in the liver transplantation field. Herein, we describe detailed surgical procedures for our rat OLT/S-OLT model and our surgical learning curves. Methods. We studied the anatomical findings, including inflow and outflow, in 100 rats following OLT/S-OLT, and determined the operator learning curves for this model. We also investigated the discrepancy between survival rates and the rates of reliable samples in OLT and S-OLT, respectively, because surgical issues destroy all experiments. Results. Learning curve data indicated that 50 cases were required for operator training plus sufficient animals to start a study. In making split-liver grafts, thoughtful consideration of inflow and outflow are crucial for successful S-OLT. Our results showed that some complications necessarily disrupt all of the experiments, and we should omit unreliable samples if any complications and/or unreasonable histology are observed, especially at early post-operative period after S-OLT. Conclusion.Although OLT/S-OLT in rats required advanced skills, this is the only liver transplantation model that provides clinically relevant and reliable results.