ACCESS SHEATHS WITH ASPIRATION FOR RETROGRADE RENAL SURGERY, RANDOMIZED COMPARATIVE OUTCOMES
试验速览
- 阶段
- 不适用
- 状态
- 尚未招募
- 发起方
- 入组人数
- 156
- 试验地点
- 1
- 主要终点
- Stone-Free Rate (SFR) at 1 Month Post-Intervention
研究概览
简要总结
The goal of this clinical trial is to learn whether the ClearPetra ureteral access sheath (Coloplast) is more effective than the Navigator ureteral access sheath (Boston Scientific) in treating intrarenal kidney stones of 1-3 cm in adult patients undergoing flexible ureteroscopy (RIRS). The main questions it aims to answer are:
Does ClearPetra achieve a higher stone-free rate at 1 month post-intervention compared to Navigator, as assessed by non-contrast abdominal-pelvic CT scan?
Does ClearPetra reduce total surgical time compared to Navigator?
Does ClearPetra lower the retreatment rate at 3 months compared to Navigator?
Does ClearPetra present a rate of clinically significant complications (Clavien-Dindo ≥ II) that is lower than or similar to Navigator?
Researchers will compare flexible ureteroscopy using the ClearPetra vacuum-assisted flexible ureteral access sheath to flexible ureteroscopy using the Navigator standard rigid ureteral access sheath, to see if ClearPetra leads to higher stone clearance rates while maintaining a comparable safety profile.
Participants will:
Undergo flexible ureteroscopy (RIRS) using one of two randomly assigned ureteral access sheaths (ClearPetra or Navigator), determined by computer-generated randomization immediately before surgery
Have a non-contrast abdominal-pelvic CT scan at 1 month post-intervention to assess stone-free status
Have a non-contrast abdominal-pelvic CT scan at 3 months post-intervention to evaluate residual fragments and the need for retreatment
Attend follow-up visits at 1 month and 3 months post-surgery for clinical assessment and complication recording
The study will be conducted at the Urology Department of Hospital Universitario Virgen del Rocío (Seville, Spain), a tertiary reference centre. A total of 156 patients will be randomized in a 1:1 ratio (78 per group), with pre-defined subgroup analyses stratified by stone size (1-2 cm vs. >2 cm). The outcome assessor evaluating CT images for stone-free rate will be blinded to treatment allocation (single-blind).
详细描述
BACKGROUND AND RATIONALE
Urinary lithiasis (kidney stone disease) affects approximately 10-15% of the population in developed countries and is characterized by high recurrence rates. Among surgical treatment options, retrograde intrarenal surgery (RIRS) using flexible ureteroscopy has become the standard-of-care approach for intrarenal stones measuring 1-3 cm, offering the advantages of a minimally invasive endoscopic approach combined with laser lithotripsy.
Ureteral access sheaths (UAS) are devices placed transurethrally prior to flexible ureteroscopy to facilitate repeated scope insertion, maintain stable ureteral access, and reduce intrapelvic pressure during the procedure. Two fundamentally different UAS designs are currently in clinical use at the study centre: (1) standard rigid sheaths, represented by the Navigator® (Boston Scientific), and (2) a novel vacuum-assisted flexible sheath, the ClearPetra® (Coloplast), which incorporates continuous negative-pressure aspiration to actively evacuate stone fragments and irrigation fluid throughout the procedure.
The theoretical advantages of vacuum-assisted UAS include improved intraoperative visibility due to continuous fluid evacuation, more efficient fragment extraction (particularly smaller dust-like fragments generated by laser pulp), potentially reduced intrapelvic pressure, and lower risk of infectious complications related to high intrarenal pressure. However, despite these mechanistic rationales and promising preliminary data, no randomised controlled trial has yet conclusively established the superiority of ClearPetra® over standard rigid sheaths in terms of stone-free rate for intrarenal lithiasis in the 1-3 cm range.
The current choice between sheath types at most urology departments - including the study centre - is made based on surgeon preference, device availability, or extrapolation from observational studies with significant methodological limitations. This genuine clinical equipoise justifies conducting a prospective randomised trial to generate Level I evidence on this clinically important question.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Treatment
- 盲法
- Single (Outcomes Assessor)
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Age ≥18 years
- •Diagnosis of intrarenal lithiasis with maximum stone diameter of 1-3 cm on preoperative non-contrast abdomino-pelvic CT scan
- •Candidate for treatment by flexible ureteroscopy (RIRS) as indicated by the treating urologist
- •Attended at the Department of Urology, Hospital Universitario Virgen del Rocío (Seville, Spain)
- •Willing and able to provide written informed consent
- •Able to comply with the study follow-up schedule (CT scan at 1 and 3 months post-intervention)
排除标准
- •Active urinary tract infection or urosepsis at the time of the planned intervention
- •Known ureteral stricture precluding passage of a ureteral access sheath
- •Pregnancy
- •Prior urinary diversion incompatible with transurethral access (e.g., urinary conduit, neobladder)
- •Bleeding disorder or anticoagulant/antiplatelet therapy that cannot be safely interrupted perioperatively
- •Stone diameter <1 cm or >3 cm on preoperative CT
- •Inability to provide informed consent (cognitive impairment, language barrier without interpreter availability)
- •Simultaneous participation in another clinical trial that could interfere with the outcomes of this study
结局指标
主要结局
Stone-Free Rate (SFR) at 1 Month Post-Intervention
时间窗: 30 days (±7 days) after surgical intervention
Proportion of patients with complete absence of residual lithiasis or presence exclusively of fragments ≤2 mm on non-contrast abdomino-pelvic CT scan performed at 30 ±7 days post-intervention. Assessed by a blinded outcomes assessor using standardised multiplanar CT reconstruction. Dichotomous variable: stone-free (yes/no). A sensitivity analysis will apply a stricter definition (0 mm, complete absence of any fragment).
次要结局
- Total Surgical Time(Intraoperative (Day 0))
- Stone-Free Rate (SFR) at 3 Months Post-Intervention(90 days (±14 days) after surgical intervention)
- Stone Volume Reduction Rate at 1 Month(30 days (±7 days) after surgical intervention)
- Immediate Endoscopic Stone-Free Rate(Intraoperative (at procedure completion, Day 0))
- Immediate Fluoroscopic Stone-Free Rate(Intraoperative (at procedure completion, Day 0))
- Retreatment Rate at 3 Months(Up to 90 days (±14 days) after surgical intervention)
- Active Stone Fragmentation Time(Intraoperative (Day 0))
- Fluoroscopy Time(Intraoperative (Day 0))
- Laser Activation Time(Intraoperative (Day 0))
- Rate of Ureteral Access Sheath Passage Failure Requiring Pre-Stenting(Intraoperative (Day 0))
- Immediate Postoperative Complications (≤30 Days)(Up to 30 days after surgical intervention)
- Late Postoperative Complications (>30 Days to 3 Months)(From 30 days to 90 days (±14 days) after surgical intervention)
- Hospital Length of Stay(From Day 0 (surgery) until hospital discharge, assessed up to 30 days)