Patterns‐of‐care and health economic analysis of robot‐assisted radical prostatectomy in the Australian public health system

Marnique Basto, Niranjan Sathianathen, Luc Te Marvelde, Shane Ryan, Jeremy Goad, Nathan Lawrentschuk, Anthony J Costello, Daniel A Moon, Alexander G Heriot, Jim Butler, Declan G Murphy

To compare patterns of care and perioperative outcomes of robotic prostatectomy to other surgical approaches, and create an economic model to assess the viability of robotic prostatectomy in the public case-mix funding system. We retrospectively reviewed all radical prostatectomies (RP) performed for localised prostate cancer in Victoria, Australia, from the Victorian Admitted Episode Dataset (VAED), a large administrative database that records all hospital inpatient episodes in Victoria, Australia's second most populous state. The first database from July 2010 to April 2013 (n=5130) was utilised to compare length of hospital stay (LOS) and blood transfusion rates (BTR) between surgical approaches. This was subsequently integrated into an economic model. A second database (n=5581) was extracted between July 2010 and June 2013, three full financial years, to depict patterns of care and make future predictions for the 2014-15 financial year, and to perform a hospital volume analysis. We then created an economic model to evaluate the incremental cost of robotic assisted radical prostatectomy (RARP) over open radical prostatectomy (ORP) and laparoscopic radical prostatectomy (LRP) incorporating the cost offset from differences in LOS and BTR. The economic model constructs estimates of the diagnosis related group (DRG) costs of ORP and LRP, adds the gross cost of the surgical robot (capital, consumables, maintenance and repairs), and manipulates these DRG costs to obtain a DRG cost per day which can be used to estimate the cost offset associated with RARP in comparison with ORP and LRP. Economic modelling was performed around a base-case scenario, assuming a 7-year robot lifespan and 124 robotic cases performed per financial year, and one and two-way sensitivity analyses performed for the 4-arm da Vinci SHD, Si and Si dual surgical systems. We identified 5581 patients who underwent radical prostatectomy in 20 Victorian hospitals utilising an open, laparoscopic or robotic surgical approach in the public and private sector. Overall, the majority of RP is performed in the Victorian private sector 4233 (75.8%), with an overall 11.5% decrease in the total number of RPs performed over the three-year study period. In the most recent financial year 820 (47%), 765 (44%) and 173 (10%) underwent RARP, ORP and LRP respectively. In the same timeframe, RARP accounted for 26% and 53% of all RPs in the public and private sector respectively. Victorian public hospitals perform a median number of 14 RPs per year, 40% of hospitals perform less than ten per year. In the public system, RARP had a mean (±SD) LOS of 1.4 days (±1.3) compared to LRP 3.6 days (±2.7) and ORP 4.8 days (±3.5) (p<0.001). Mean BTRs were 0%, 6% and 15% for RARP, LRP and ORP respectively (p<0.001). The incremental cost per case of RARP over ORP and LRP is $442 and $2092 respectively for the da Vinci S model, $1,933 and $3,583 for the da Vinci Si model and $3,548 and $5,198 for the da Vinci Si dual. RARP can become cost equivalent with ORP where approximately 140 cases per year are performed in the base-case scenario. RARP has become the dominant approach to prostatectomy with significant reductions in LOS and BTR. This translates to significant cost offset, further enhanced by increasing the case volume, extending the lifespan of the robot and reductions in the cost of consumables and capital. This article is protected by copyright. All rights reserved.