Learning Curve for Rat Intestinal Transplantation: Milestones From a Single Surgeon's Perspective

The rat intestinal transplant (ITx) model is associated with a steep and challenging learning curve (LC) due to the microsurgical skills it requires. Although benchmark values are well-defined in the literature, clear milestones guiding progression along this curve are lacking, which limits its widespread use. Here, we present our methodology for assessing LC progression and achievement.

We describe the experience of a single surgeon developing the rat ITx model without prior microsurgical training. The LC was divided into 3 stepwise milestones: (1) acquisition of microsurgical skills, (2) development of intestinal graft procurement, and (3) development of intestinal graft implantation. LC progression was assessed using surgical times (milestones 2 and 3) and survival rate (milestone 3), according to the number of procedures performed. Based on anastomosis time, a cumulative sum chart analysis was used to determine the number of procedures required to reach LC proficiency.

After initial microsurgical training, chicken thighs and rat cadavers were used to practice the key steps of the ITx model. Subsequently, intestinal procurement and implantation in living rats were performed to ultimately complete the 3 defined milestones. Analysis of the cumulative sum chart indicated that 34 ITx procedures were required to reach anastomosis time targets (linear regression adjusted R² = 0.95), which was directly associated with an increased 7-day survival rate.

Our methodology, based on stepwise milestones, enabled the development of the rat ITx model. Following the completion of milestones 1 and 2, 34 ITx procedures were required to complete the LC.