Learning curve of laparoscopic nephrectomy: a prospective pilot study

Abstract
Background
Learning curve of laparoscopic nephrectomy (LN) is mainly affected by two main factors: plotting performance and experience. However, there is paucity in the literature addressing the number of cases required to adopt LN. Herein, we aimed to assess the learning curve of LN for various renal disorders and number of cases required to adopt the technique. Between September 2015 and December 2017, consecutive patients undergoing LN for various renal diseases were enrolled in this study. Patients were divided into two groups, the first 20 cases (group A) and subsequent 20 cases (group B). All procedures were performed by a single trainee urologist under supervision of an expert endourologist. Learning curve was assessed using operative time and incidence of complications.

Results
A total of 40 patients were included in this pilot clinical study. Mean age was 38.2 ± 16.3 years. The mean operative time for patients in group B was significantly lower than the mean operative time for patients in group A (108.5 vs. 139.3 min, p < 0.05). However, there were no significant differences between both groups in terms of intraoperative blood loss (86 vs. 104 ml; p = 0.081), conversion to open surgery (5% vs. 10%; p = 0.256) and postoperative complications (5% vs. 15%; p = 0.09) for group B and group A, respectively. Similarly, there was no significant difference between both groups in terms of hospital stay (42 ± 8 vs. 46 ± 11 h p = 0.01). The trainee surgeon reached a plateau after 22 cases.

Conclusions
Our study suggests that a minimum of 22 LN procedures are needed in order to adopt the technique of laparoscopic nephrectomy. Learning curve of LN is mainly affected by number of performed procedures within a short period of time.