The learning curve in laparoscopic adrenalectomy

Laparoscopic adrenalectomy (LA) is the procedure of choice for surgical management of most adrenal tumors. LA learning curve (LC) varies among surgeons and may be influenced by factors depending on surgeon, patient, and lesion peculiarities. The aim of this study was to evaluate the LC by multi-dimensional analysis.

Between August 1994 and August 2005, 241 LA were performed in our department. Data were prospectively collected. The pre-operative variables evaluated were patient-related (age, gender, body mass index, co-morbidities) and disease-related (histology, size, and side of lesion). Level of experience of surgical team and surgical approach (anterior, flank, submesocolic routes) were evaluated as well. Flank approached and bilateral procedures were excluded, while submesocolic LA, were collected separately. Operating time (OpT), conversion rate (CR), intra-operative and post-operative complications were evaluated. Patient, surgeon, and procedure-related factors involved in LC were investigated by a multi-factorial logistic regression analysis.

Body mass index, side, size, histology, technology improvement, and experience of surgical team, evaluated through the progressive series of surgical procedures, were independent predictors of CR and OpT. The CR for right adrenalectomy was 3% (3 cases) compared to 4.2% for left side (6 cases). The submesocolic approach significantly influenced OpT, but not CR. Mean OpT for right and left LA was 83 and 109 min, respectively. Based on surgical experience increase, the OpT and CR flattened their curves, roughly at 30 and 40 procedures for right and left LA, respectively. Post-operative complications did not change considerably throughout the series. Readmission rate within 30 days was negligible.

Manifold factors may affect LC and outcome in LA. Their knowledge may support teaching activities as well as reducing conversion and complication rates.