Challenges of Retrograde Ureteroscopic Procedures in Overweight Patients

Obesity and urolithiasis are both prevalent conditions that have an impact on the healthcare system. The ureteric diameter and accessibility play a crucial role in the management of urolithiasis in both overweight and normal weight patients. Studies have shown that obesity can lead to changes in ureter diameter where excessive body fat can exert pressure on the kidneys, causing them to enlarge in size and this enlargement can result in a compression of the adjacent structures, including the ureter. The aim of this study is to assess the incidence of intraoperative challenges faced during retrograde ureteroscopic procedures in overweight patients with ureteric and renal calculi.

We retrospectively reviewed patients who underwent retrograde ureteroscopic surgery (RURS) for urolithiasis from 1^st January 2021 until 30^th August 2023. The outcome and any complications were documented and compared with the patient's Body Mass Index (BMI). All patients who undergo RURS in our facility have to have a Non-Contrast CT scan prior to surgery. Procedural success was determined by the ability to obtain access to the stone site intraoperatively and stone-free status in kidney, ureter, and bladder (KUB) X-ray post-operatively. Post-operative complications were recorded up to two weeks post-operatively and classified according to the Calvein Dindo Classification.

Our total sample size was 146 patients out of which 75 were overweight and 71 were normal weight patients. In 34 (45%) of overweight patients' access to the ureter was restricted due to a narrow ureteric orifice with ureteroscopy not successful; on the contrary 13 (18%) of normal weight patients faced this same issue. This was statistically significant with a p-value of .004. The stone clearance rates were 91% and 95% in overweight and normal weight patients respectively, which is higher in normal weight patients however this difference was not found to be a statistically significant finding (p-value .028). Overweight patients had 12% Grade I and 8% Grade II complications whereas normal weight patients had 11% Grade I complications and 1.4% Grade II with no higher-grade complications.

Retrograde ureteroscopic procedures are a safe treatment modality for patients with urolithiasis in both overweight and normal weight populations. They are shown to have similar success rates between both populations once ureteric access is obtained. However, access failure rates are shown to be slightly higher in overweight patients. Hence, further preoperative patient counselling and technical considerations should be undertaken.