P-01-041 A single center analysis on the learning curve of male to female peno-scrotal vaginoplasty by multiple outcome measures

Abstract

To asses and quantify the learning curve (LC) of the peno-scrotal inversion flap vaginoplasty (PSV) of a single surgeon based on a single center retrospective study. We retrospectively reviewed clinical records of 69 patients underwent PSV from January 2005 to January 2015. In the current analysis we selected as primary outcome variable of surgical process, the operative time. The measure selected as secondary outcome value were vaginal depth, the amount of blood loss, the length of the hospital stay and the postoperative complication rate, which was evaluated as the incidence of any major postoperative complication. In the present analysis we used two validated methods to statistically quantify the LC: a graphic visual one through scatter plot representation and the splitting group one. The splitting group analysis revealed a statistically remarkable difference between the groups for the operative time (p < 0,01), the vaginal depth (p = 0,01), the hospital stay (p < 0,01) and the intraoperative complication rate (p = 0.01). On the contrary, no differences were evidenced between the cohorts for the amount of blood loss (p = 0,08). The operative time decreased significantly from 350 minutes in the 1st group to 220 minutes after 35 cases, tending to a visible stabilization in the last cohorts. Focusing the attention on the vaginal depth, a part from a solitary peak seen in the 1st group, it tended to be stable until 45 performed cases, while it had a slight progressive increase in the consequent cohorts. The hospital stay was characterized by a progressive decrease, excluding an isolated peak visible in the 5th group, and it got to stabilization after 55 cases. On the contrary, the blood loss resulted stable within all the cohorts, reaching two isolated peaks after 40 and 55 cases. The graphic representation of the intraoperative, was represented by an overall decrease, from 20% in the 1st to 0% in the last group. The scatter plot logarithmic demonstrated a clear visible LC for most parameters.