Considering Costs of Complications in Bariatric Surgery for the Evaluation of New Technologies based on the Example of Surgical Robotics

Research Article

Austin J Obes & Metab Synd. 2020; 4(2): 1018.

Considering Costs of Complications in Bariatric Surgery for the Evaluation of New Technologies based on the Example of Surgical Robotics

Hagen ME1*, Douissard J1, Cohen G2, Jung MK1, Buchs NC1 and Torso C1

1Division of Digestive and Transplant Surgery, Department of Surgery, University Hospital Geneva, Switzerland

2Medical Controlling, University Hospital Geneva, Switzerland

*Corresponding author: Monika E Hagen, Division of Digestive and Transplant Surgery, Department of Surgery, University Hospital Geneva, 4 Rue Gabrielle-Perret-Gentil, 1211 Geneva, Switzerland

Received: June 08, 2020; Accepted: July 03, 2020; Published: July 10, 2020


Purpose: The purpose of this analysis is to analyze the cost of complications of bariatric surgery to support the economic evaluation of new surgical technologies based on the example of robotic surgery.

Methods: Patients who underwent robotic bariatric surgery from 2014 to 2015 with complete economic data were included. The itemized and treatment costs were derived using the REKOLE method and stratified using the Clavien- Dindo classification.

Results: A total of 195 patients were included. 88.7% of patients underwent primary Roux-en-Y gastric bypass surgery, 6.2% underwent gastric sleeve resection, and 5.1% underwent revisional surgery. 136 patients had no complication, 42 were classified with a Clavien I complication, 6 with a Clavien II complication, and 11 with a Clavien III complication. The mean treatment costs were USD 19,857 for patients without complication, USD 20,575 for patients with a Clavien I complication, USD 29,069 for a Clavien II complication, and USD 52,473 for a Clavien III complication.

Conclusion: Complications are important cost drivers with an incremental correlation to the Clavien-Dindo classification. While minor complications have a clear impact, major complications have an exponential effect on overall costs. As such, a decrease in complications might justify higher procedural costs due to the use of new technologies.

Keywords: Cost; Complications; Robotic Surgery; Gastric Bypass; RYGB; Bariatric Surgery


New surgical techniques like minimally invasive surgeries, including robotics provide patient benefits such as shorter hospital stay and reduced surgical trauma when compared to the traditional open approach [1]. However, several studies have shown higher costs for robotic surgery when compared with laparoscopy or open surgery [2-4]. Although new technologies are integral to the advancement of surgical care, they often have – sometimes obstructive - incremental costs that are typically associated with significant upfront investments for the initial purchase as well as procedure-related costs, which is also the case for surgical robotics [5,6].

Since the first published robotic procedures more than two decades ago, the adoption of this technology has increased across surgical specialties with a clear uptake in recent years [7]. However, adoption of robotic surgery still limited to the minority of overall world-wide performed surgical procedures [7]. An important factor that contributes to the limited adoption are the high costs of these systems while the clinical value is still under evaluation as independent high impact factor. As an example, the da Vinci Surgical System – the currently most widely used robotic system - accrues capital costs ranging from USD 0.5M to 2.5M, the annual service costs range from USD 80K to 190K, and the per procedure instruments and accessories’ costs range from USD 700 to 3,500 [7]. These costs are – depending on the structure of the respective healthcare environment – at the burden of either the healthcare provider, the insurer, the patient, or another third party [5]. If these upfront costs cannot be balanced with other factors, they might become prohibitive, particularly in healthcare systems that utilize a flat-fee reimbursement. In addition, high-quality and industry-independent research supporting clinical superiority of robotics over conventional approaches is missing at present. As such, technologies should not only be evaluated for its safety and efficacy, but also its clinical impact and cost efficiency.

Potential options for reducing the cost of surgeries using expensive equipment include savings on other material and the improvement of surgical quality, resulting in fewer complications. This concept has been demonstrated for robotic gastric bypass surgeries [8]. However, detailed research is complex, and it seems intriguing to understand the cost structures of surgical complications to estimate the impact of clinical improvements on the cost of surgery.

To date, there is no available reliable model that estimates the specific costs of complications, which could facilitate modeling the cost-effectiveness of new technologies. This study aims to analyze the costs of complications during bariatric surgery and discuss these costs in light of incremental costs for new technologies using the example of robotics.

Materials and Methods


This is a retrospective single center analysis of patients who underwent bariatric surgery between January 2014 and December 2015 at the University Hospital Geneva (Switzerland). Patients with missing economic data were excluded.

Patients were operated with either a fully robotic or hybrid approach using the da Vinci Si or Xi Surgical System (Intuitive Surgical Inc., Sunnyvale, CA, USA). The procedures have been previously described [8-11].

Patients routinely entered the hospital the morning of the procedure and stayed in the intermediate care unit until released from anesthesia to the standard ward. Routine blood testing was performed on day 1 and patients were discharged after successful realimentation, pain control with oral medication, and a willingness to return home. If medically necessary, deviations from this path were planned and executed.

Data collection

Clinical data was derived from our prospective database and individual cases’ charts were reviewed is information was missing. Patients were stratified using the Clavien-Dindo Classification as per the original publication [12]. In case patients underwent additional imaging or other testing outside the previously described clinical pathway, they were classified as a Clavien-Dindo I case, even if imaging or other testing was negative and not strictly indicated (for example ordered by a resident without approval).

The medical cost data included in this study was obtained using the REKOLE method [13]. The REKOLE method is the Swiss national cost accounting system used in hospitals in Switzerland. The REKOLE system was introduced because the Swiss government opted for comparable and transparent hospital costs. Under the REKOLE method, costs are defined as total direct costs of inpatient care and all hospitals adhere to a minimum standard. The REKOLE system was established at the same time as the change of the reimbursement system from the per-diem payment system to the Diagnose Related Groups (DRG) payment system after January 2012, and it has been used since then for academic cost analyses [5].

Statistical analysis

Statistical analysis was carried with Stata 15.0 software (Stata Corp., College Station, USA). P-value lower than 0.05 was considered statistically significant. Descriptive statistics included means and standard deviation for continuous data, or frequency and percentage for discrete data. Considering more than 2 groups of complications, costs comparisons were carried through one-way analysis of variances (ANOVA) assuming the normal distribution of costs within groups, independence of observations and normal distribution of variances. Tukey’s honest significant difference (Tukey HSD) test was chosen as post-hoc test to explore differences between groups and determine their relative statistical significance.


195 patients were included in this analysis. 173 (88.7%) underwent primary gastric bypass, 12 (6.2%) underwent gastric sleeve resection, and 10 (5.1%) underwent a revisional procedure. The mean age in this cohort was 42.9 (+/-11) years and 145 (74.4%) were female. The mean BMI was 43.6 (+/- 5.6) kg/m2. 126 (64.6%) were classified as American Society of Anesthesiologists (ASA) 1 or 2 and 69 (53.4%) as ASA 3 or 4. The details regarding demographic parameters can be found in Table 1.