SOUL Trial Investigates Stent Omission After Ureteroscopy for Kidney Stones
Key Insights
The SOUL study is a pragmatic trial comparing ureteral stent placement versus stent omission after uncomplicated ureteroscopy (search) for kidney stone management.
The primary outcomes are patient-reported pain interference and unplanned healthcare utilization within 30 days post-ureteroscopy (search).
The trial includes both a randomized cohort and an observational cohort to assess the impact of stent omission on patient outcomes.
The Michigan Urological Surgery Improvement Collaborative (MUSIC (search)) is conducting the Stent Omission after Ureteroscopy (search) and Lithotripsy (SOUL) trial to evaluate the effectiveness of omitting ureteral stents following uncomplicated ureteroscopy for kidney stones (search). The pragmatic trial compares stent placement with stent omission, both considered standard clinical care.
The SOUL study employs a mixed-methods approach, including a randomized controlled trial (RCT) cohort and an observational cohort. Patients undergoing ureteroscopy (search) at participating sites are eligible. In the RCT cohort, patients are randomized 1:1 to either stent placement or stent omission. The observational cohort includes patients who decline randomization but are still followed to assess outcomes based on the urologist's decision regarding stent placement.
The primary outcomes of the SOUL trial are the change in Patient-Reported Outcomes Measurement Information System (PROMIS) Pain Interference T-score at 7-10 days post-surgery compared to baseline, and unplanned stone treatment-related healthcare utilization within 30 days of ureteroscopy (search). Healthcare utilization is assessed using a hierarchical composite endpoint including ICU care, unplanned hospitalization, additional procedures, emergency department visits, and unplanned clinic visits.
Secondary outcomes include PROMIS Pain Interference and Intensity scores at 4-6 weeks post-surgery, lower urinary tract symptoms, patient satisfaction, and days taken off work. Exploratory outcomes involve ecological momentary assessments (EMA) of pain and medication use, postoperative imaging findings, stone-free rates, and qualitative interviews with patients and surgeons.
The trial plans to enroll 264 patients in the randomization cohort to attain 224 randomized patients and 528 patients in the observational cohort. The sample size is powered to detect a clinically meaningful difference of 5 points in PROMIS Pain Interference scores and a 67% marginal probabilistic index in healthcare utilization between the stent placement and stent omission groups.
Participating urologists and staff receive extensive training and support to ensure adherence to the trial protocol. A dedicated website provides resources and facilitates rapid accrual, especially for patients presenting acutely through the emergency department. The pragmatic design allows for continued standard postoperative care as directed by the treating urologist.
The SOUL trial seeks to provide evidence on whether routine stent placement after uncomplicated ureteroscopy (search) can be safely omitted, potentially reducing patient discomfort and healthcare costs. The results of this study could significantly influence clinical practice guidelines and improve patient care in urology.