Comparison of Learning Curves for Major and Minor Laparoscopic Liver Resection

Background: Because laparoscopic liver resection (LLR) has a steep learning curve, analyzing experience is important for trainees. Several authors have described the learning curve of LLR, without comparing the learning curves between major and minor LLR. Methods: Perioperative data were retrieved from the medical records of 170 consecutive patients who underwent LLR by a single surgeon at a tertiary hospital. Learning curves were generated and compared between major and minor LLR using cumulative sum control charts and the moving average. Results: Major and minor LLR was performed in 96 and 74 patients, respectively. The learning curves showed a steady state after case 50 for major LLR. Because of discordant results in minor LLR, subgroup analyses were performed, showing competency in LLR after cases 25 and 35 for left lateral sectionectomy and tumorectomy, respectively. Transfused red blood cell volume (0.6 versus 2.2 packs, P<.001) decreased after achievement of competence in major LLR. Blood loss exceeding 500mL (odds ratio 2.395, 95% confidence interval 1.096-5.233, P=.028) was independently associated with LLR failure. Conclusions: The number of cases required to accomplish LLR differed according to the extent of resection. Extensive blood loss was independently associated with LLR failure.