Trial no.:	PACTR202512556567081	Date of Registration:	24/12/2025
Trial Status:	Registered in accordance with WHO and ICMJE standards

TRIAL DESCRIPTION

Public title

DRAIN-FURS Trial: Drainage-Assisted Flexible Ureteroscopy versus Ureteral Access Sheath FURS for Upper Urinary Tract Stones

Official scientific title

A Prospective Randomized Controlled Trial Comparing Drainage-Assisted Flexible Ureteroscopy Using Percutaneous Nephrostomy Versus Ureteral Access Sheath in the Management of Upper Urinary Tract Stones

Brief summary describing the background and objectives of the trial

Flexible ureteroscopy (FURS) is an established minimally invasive treatment for renal and upper ureteric stones ≤20 mm. Ureteral access sheaths (UAS) are widely used to facilitate repeated access, improve irrigation, and reduce intrarenal pressure. However, UAS use has been associated with ureteral ischemia, mucosal injury, and potential long-term stricture formation due to ureteral overdistension. Elevated intrarenal pressure during FURS has been implicated in pyelovenous and pyelolymphatic backflow, contributing to postoperative infectious complications including fever, urinary tract infection, and sepsis. Pressure-modulating strategies have therefore gained interest as a means of improving safety. Meta-analyses evaluating suction-assisted or pressure-modulated FURS have demonstrated a significant reduction in overall perioperative complications compared with traditional UAS-assisted FURS, with pooled odds ratios as low as 0.37. These analyses also show reduced complications across both low-grade (Clavien–Dindo I–II) and high-grade (≥III) events. However, high-quality randomized trials focusing on safety as a primary endpoint and avoiding ureteral overdistension remain limited. Percutaneous nephrostomy–assisted drainage during FURS provides continuous low-pressure renal outflow without the need for ureteral sheath placement, potentially preserving ureteral integrity while maintaining operative efficiency. The DRAIN-FURS Trial is designed to address this evidence gap. Primary Objective is to compare the overall perioperative safety of drainage-assisted flexible ureteroscopy using percutaneous nephrostomy versus standard flexible ureteroscopy using a ureteral access sheath, assessed by the rate of overall complications graded according to the Clavien–Dindo classification. Secondary Objectives To compare operative time and fluoroscopy time between the two techniques. To evaluate stone-free rates on non-contrast CT scan at one and three months

Type of trial

RCT

Acronym (If the trial has an acronym then please provide)

Disease(s) or condition(s) being studied

Urological and Genital Diseases

Sub-Disease(s) or condition(s) being studied

Purpose of the trial

Treatment: Surgery

Anticipated trial start date

01/01/2026

Actual trial start date

Anticipated date of last follow up

30/06/2026

Actual Last follow-up date

Anticipated target sample size (number of participants)

140

Actual target sample size (number of participants)

Recruitment status

Active, not recruiting

Publication URL

Secondary Ids	Issuing authority/Trial register

STUDY DESIGN
Intervention assignment	Allocation to intervention	If randomised, describe how the allocation sequence was generated	Describe how the allocation sequence/code was concealed from the person allocating the participants to the intervention arms	Masking	If masking / blinding was used
Parallel: different groups receive different interventions at same time during study	Randomised	Simple randomization using a randomization table created by a computer software program	Sealed opaque envelopes	Open-label(Masking Not Used)

INTERVENTIONS
Intervention type	Intervention name	Dose	Duration	Intervention description	Group size	Nature of control
Experimental Group	Drainage Assisted Flexible Ureteroscopy		Not applicable	Patient Position and Anesthesia • All procedures are performed under general anesthesia. • The patient is placed in a modified supine position (e.g. Galdakao-modified supine Valdivia position). Ureteric Catheter Placement • A cystoscopy is performed in the supine position. • A 5-Fr ureteric catheter is inserted into the renal pelvis under cystoscopic guidance. • Retrograde contrast injection is used to opacify the pelvicalyceal system and guide calyceal puncture. Percutaneous Nephrostomy Access • Under fluoroscopic and/or ultrasound guidance, a percutaneous puncture is made into the targeted lower renal calyx using an 18-gauge needle. • Correct access is confirmed by urine aspiration and contrast injection. • A guidewire is advanced into the renal pelvis. • The tract is gently dilated to accommodate a 10–14 Fr nephrostomy tract, sufficient for continuous drainage rather than nephroscopic manipulation. • A percutaneous nephrostomy tube is placed and connected to an external drainage system, providing continuous low-pressure renal outflow throughout the procedure. Flexible Ureteroscopy and Stone Fragmentation • Flexible ureteroscopy is performed retrogradely via the ureter. • Stones are fragmented using a Holmium:YAG laser. • Stone clearance is confirmed endoscopically and fluoroscopically. Drainage and Closure • At the end of the procedure, the nephrostomy tube (10–14 Fr) is left in situ. • A ureteric stent may be placed based on intraoperative findings. • The percutaneous access site is closed with a single absorbable suture, and a sterile dressing is applied.	70
Control Group	Standard Flexible Ureteroscopy with Ureteral Access Sheath		Not applicable	Patient Position and Anesthesia • All procedures are performed under general anesthesia. • The patient is placed in the lithotomy position. Ureteral Access and Sheath Placement • Cystoscopy is performed to identify the ureteric orifice. • A guidewire is advanced into the renal pelvis. • In pre-stented patients, the JJ stent is removed before guidewire placement. • An 11–13 Fr ureteral access sheath is inserted under fluoroscopic guidance into the proximal ureter. Flexible Ureteroscopy and Stone Fragmentation • Flexible ureteroscopy is performed through the access sheath. • Stones are fragmented using a Holmium:YAG laser. • Irrigation is maintained through the ureteroscope, with passive outflow through the access sheath. • Stone clearance is assessed visually and fluoroscopically. Drainage and Closure • The ureteral access sheath is removed at the end of the procedure. • A ureteric stent is inserted based on intraoperative findings and surgeon discretion. • No percutaneous renal access is created in this group.	70	Active-Treatment of Control Group

ELIGIBILITY CRITERIA
List inclusion criteria	List exclusion criteria	Age Category	Minimum age	Maximum age	Gender
Age ≥18 years Renal and/or upper third ureteric stones ≤20 mm Eligible for flexible ureteroscopy Ability to provide informed consent	1. Staghorn or multiple calyceal stones. 2. Abnormal renal anatomy (horseshoe, duplex, malrotated kidney, PUJ obstruction, diverticulum). 3. Concomitant ureteric stones or ureteral pathology. 4. Active urinary tract infection or untreated bacteriuria. 5. Bleeding diathesis or anticoagulant use not correctable. 6. Pregnancy. 7. Severe comorbidities precluding anesthesia. 8. Previous renal surgery on the same side. 9. Solitary kidney, CKD patients or inability to complete follow-up.	80 and over: 80+ Year,Adolescent: 13 Year(s)-17 Year(s),Adult: 18 Year(s)-44 Year(s),Aged: 65 Year(s)-79 Year(s),Middle Aged: 45 Year(s)-64 Year(s)	18 Year(s)	85 Year(s)	Both

ETHICS APPROVAL

Has the study received appropriate ethics committee approval

Date the study will be submitted for approval

Date of approval

Name of the ethics committee

Yes

21/05/2025

Research Ethics Committee at Faculty of Medicine Tanta University

Ethics Committee Address
Street address	City	Postal code	Country
2 El Geesh Street, Medical Campus	Tanta	31527	Egypt

OUTCOMES
Type of outcome	Outcome	Timepoint(s) at which outcome measured
Primary Outcome	Overall perioperative complications (assessed using Clavien–Dindo grade)	Intraoperative , early postoperative within 1 week, at 3 months
Secondary Outcome	• Operative time (minutes). • Fluoroscopy time (seconds) and radiation dose (mGy·cm² if available). • Post-op stenting (yes/no; dwell time). • Length of stay (days). • Retreatment/auxiliary procedures within 3 months.	Intraoperative , early postoperative within 1 week, at 3 months

RECRUITMENT CENTRES
Name of recruitment centre	Street address	City	Postal code	Country
Tanta University Hospital	2 El Geish Street	Tanta		Egypt

FUNDING SOURCES
Name of source	Street address	City	Postal code	Country
Tanta University Faculty of Medicine	2 El Geesh street, Medical Campus	Tanta		Egypt

SPONSORS
Sponsor level	Name	Street address	City	Postal code	Country	Nature of sponsor
Primary Sponsor	Tanta University Hospital	2 El Geesh Street, Medical Campus	Tanta		Egypt	University

COLLABORATORS
Name	Street address	City	Postal code	Country

CONTACT PEOPLE
Role	Name	Email	Phone	Street address
Principal Investigator	Ahmad Wageeh	ahmedwagehgeho@gmail.com	00201060434919	Urology and Nephrology Centre, Medical Campus, 2 ElGeish street
City	Postal code	Country	Position/Affiliation
Tanta		Egypt	Assistant Lecturer and Registrar of Urology
Role	Name	Email	Phone	Street address
Scientific Enquiries	Mohammed Lotfi Amer Lotfi Amer	drmlamer@med.tanta.edu.eg	00201001862621	Urology and Nephrology Centre, Medical Campus, 2 ElGeish street
City	Postal code	Country	Position/Affiliation
Tanta		Egypt	Lecturer and consultant of Urology
Role	Name	Email	Phone	Street address
Public Enquiries	Abdalla Homouda	abdallah.hamouda@med.tanta.edu.eg	00201123911654	Urology and Nephrology Centre, Medical Campus, 2 ElGeish street
City	Postal code	Country	Position/Affiliation
Tanta		Egypt	Lecturer and consultant of Urology

REPORTING
Share IPD	Description	Additional Document Types	Sharing Time Frame	Key Access Criteria
Yes	Individual participant data will be available (including data dictionaries). Individual participant data that underlie the results reported in this article, after deidentification (text, tables, figures, and appendices), will be available. The study protocol will be available. Data will be available immediately following publication. No end date. Data will be available to researchers who provide a methodologically sound proposal for any type of analysis. Proposals should be directed to drmlamer@med.tanta.edu.eg. To gain access, data requestors will need to sign a data access agreement. Data are available for 5 years at a third-party website (link to be included later).	Study Protocol	Immediately after publication	Any researcher who provides a methodologically sound proposal and signs a data access consent form.
URL	Results Available	Results Summary	Result Posting Date	First Journal Publication Date
	No
Result Upload 1:	Result Upload 2:	Result Upload 3:	Result Upload 4:	Result Upload 5:

Result URL Hyperlinks	Link To Protocol
Result URL Hyperlinks

Changes to trial information

Pan African Clinical Trials Registry