Abstract: Background Insufflation pressures of or in excess of 25 mm Hg CO2 are routinely used during posterior retroperitoneoscopic adrenalectomy (PRA) in most centres. A critical analysis of the surgical literature provides limited evidence to support this strategy. Objective To determine whether high pressure (≥ 25 mm Hg) compared with lower pressure ( 25 mm Hg) retroperitoneoscopy reduces operating time and complications.brbrMethodsbrA multi-centre retrospective cohort study was performed using data collected over a period of almost one decade (1st November 2008 until 1st February 2018) from surgical centres in Germany. A total of 1032 patients with benign adrenal tumours were identified. We compared patients undergoing PRA with insufflation pressures of 25 mm Hg (G20 group) versus ≥ 25 mm Hg (G25 group). A propensity score matching analysis was performed using BMI, tumour size and surgeon's experience as independent variables. The main outcomes were (1) the incidence of perioperative complications and (2) the length of operating time.brbrResultsbrThe baseline patient characteristics were similar in both groups, with the exception of tumour size, BMI and surgeon's experience in PRA. After propensity score matching, perioperative outcomes, especially perioperative complications (3.7% vs. 5.5% in G20 and G25, respectively; p = 0.335) and operation duration (47 min vs. 45 min in G20 and G25, respectively; p = 0.673), did not significantly differ between the groups.br