Background: New surgical techniques should be formally evaluated for feasibility and safety. As a model for this evaluation, this study examines the authors' institution's experience with splenectomy for benign and malignant hematologic disease since the introduction of laparoscopic splenectomy (LS) in 1996. The authors present the evaluation of the recognized surgeon/institutional learning curve using CUSUM (cumulative sum) analysis.
Methods: This is a single institution retrospective chart review of consecutive splenectomies for hematologic disease performed between 1996 and 2008. The primary outcome was conversion to open splenectomy. The learning curve for LS was evaluated using CUSUM analysis.
Results: A total of 123 splenectomies were performed for benign (51.2%) or malignant (48.7%) hematologic disease. 58% of patients underwent planned LS, with a 21% conversion rate. The surgeon's overall learning curves for LS, as well as that for malignant disease, were maintained within acceptable conversion thresholds. However, the learning curve for benign disease did cross the unacceptable conversion threshold at case 29. With additional experience, the curve again approached the acceptable conversion threshold. Patients with malignant disease were significantly older (P = .0004), had larger spleens (P = .0004), were more likely to undergo open splenectomy (P = .001), and had longer lengths of stay (P = .01). However, there was no significant difference in operative time, transfusion requirements, morbidity rates, or mortality rates between patients with benign and malignant disease.
Conclusion: LS, for benign or for malignant hematologic disease, is associated with a significant learning curve. This evaluation model illustrates that careful patient selection and ongoing quality assessment is essential when introducing a new technique.