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Impact Ureteral Sheath Design During Ureteroscopy

The Impact of Ureteral Access Sheath Design on Ease of Placement and Ureteral Wall Injury During Flexible Ureteroscopy

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT03349099
Enrollment
95
Registered
2017-11-21
Start date
2014-06-27
Completion date
2016-07-31
Last updated
2018-01-23

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Nephrolithiasis, Renal Stone, Urolithiasis

Brief summary

The purpose of this study is to assess whether one of two ureteral access sheaths is safer for patients undergoing ureteroscopy. Both sheaths are FDA approved devices and commercially available. The investigators will compare the ability of sheaths to access the kidney through the ureter and will compare damage done to the ureter after completion of the procedure. Access sheaths are standard of care for this procedure; this study seeks to optimize outcomes for patients. Patients undergoing ureteroscopy who do not have ureteral stents in place and who have not had an ipsilateral procedure within 90 days will be recruited and consented.

Detailed description

The purpose of this study is to compare two ureteral access sheaths in how the sheaths damage the ureter during flexible ureteroscopy. Condition Intervention Kidney Stones Nephrolithiasis Urolithiasis Device: Cook Flexor or Boston Scientific Navigator HD Study Type: Interventional Study Design: Intervention Model: Two group randomized assignment Masking: Single blind Primary Purpose: Treatment Primary Outcome Measures: • Successful placement of sheath (yes or no). Secondary Outcome Measures: * Subjective rating of damage to ureter. At the completion of the procedure, video of the intraluminal ureter is recorded as the sheath is withdrawn. Videos are analyzed by two blinded staff endourologists to score ureteral injury on a standard 5-point scale (0 to 4); reference Traxer and Thomas. * Ease of placement of each sheath. Surgeons will be asked to subjectively rate the ease of placement on a standardized scale from 0 to 4, 4 being easiest which will be rated by the surgeon who inserted the sheath immediately after placement. Arms Assigned Interventions Device: Cook Flexor and Boston Scientific Navigator HD Device: Cook Flexor or Boston Scientific Navigator HD Patients will be assigned to one of two ureteral access sheaths. If the first sheath is failed to be placed, the backup sheath will be attempted. Standard ureteroscopy will take place. The intervention takes place before the ureteral access sheath is placed. The patient will be randomized to one of the two sheaths. The randomized 12/14Fr sheath will be attempted. If placed successfully, the rest of the operation continues as planned. If the initial sheath is unable to be placed, a second backup sheath (opposite brand) will be used, also in size 12/14Fr. The surgeon will be asked to rate the ease of placement of the sheath on a standardized scale. If these sheaths fail, it is the surgeon's discretion to continue with the smaller sheath, continue without sheath or place stents and attempt the procedure at a later date. The operation is then continued in standard fashion. Once the ureteroscopy is completed, before the scope and access sheath are removed, video recording of the ureter will be conducted as the ureteroscopy and sheath are removed. Videos will be analyzed by blinded urologists who will rate the extent of ureteral damage on a standardized scale of 0 to 4 according to the study published by Traxer et al. 2013. Intra-operative data includes total time of initial sheath insertion (in seconds), total time sheath is in place (minutes) from placement to removal, and use of laser. Differences in operative time, ease of placement, ability to maintain access, and ease of instrument passage are also evaluated between devices, as well as success rates, and device failure rates and post-operative complications. Means are compared using a t-test and proportions are compared using a chi-squared test. An intention to treat model is used for statistical analysis. When video ratings differ between surgeons, the higher rating of damage will be used. Inter-rater reliability is assessed with Cohen's kappa coefficient. After the study, subjects will not be contacted. The investigators will collect data from participants' medical records including information of whether participants develop complications or return for a subsequent procedure as well as size and location of kidney stones prior to the surgery.

Interventions

DEVICECook Flexor

ureteral access sheath

DEVICEBoston Scientific Navigator

ureteral access sheath

Sponsors

The Cleveland Clinic
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Caregiver)

Masking description

Videos will be analyzed by blinded urologists who will rate the extent of ureteral damage on a standardized scale of 0 to 4 according to the study published by Traxer et al. 2013. After the study, subjects will not be contacted.

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* Patients planned for ureteroscopy * Current CT scan within 90-days before the operation * Able to give informed consent * Ages 18 years and older

Exclusion criteria

* Inability to give informed consent * Age less than 18 years * Pregnant * Stones in the ureter * Having previous ipsilateral ureteral or renal surgery within 90 days * Having stents placed in ipsilateral ureter within 90 days

Design outcomes

Primary

MeasureTime frameDescription
Number of Participants With Successful Sheath PlacementOne time point - at the beginning of the procedureThe surgeon documents whether there was Successful placement of sheath (yes or no)

Secondary

MeasureTime frameDescription
Number of Participants With Injury to the UreterOne time point - at the completion of the procedureSubjective rating of damage to ureter. At the completion of the procedure, video of the intraluminal ureter is recorded as the sheath is withdrawn. Videos are analyzed by two blinded staff endourologists who score ureteral injury on a standard 5-point scale (0 to 4); reference Traxer and Thomas.
Ease of Sheath PlacementOne time point - at the completion of the procedureSurgeons will be asked to subjectively rate the ease of placement on a standardized scale from 0 to 4, 4 being easiest which will be rated by the surgeon who inserted the sheath immediately after placement.

Participant flow

Recruitment details

Recruitment was conducted from urology pre-operative clinic from July 1 2014 to May 31 2016

Pre-assignment details

No patients were excluded prior to assignment.

Participants by arm

ArmCount
Cook Flexor
ureteral access sheath Cook Flexor: ureteral access sheath
48
Boston Scientific Navigator HD
ureteral access sheath Boston Scientific Navigator: ureteral access sheath
47
Total95

Withdrawals & dropouts

PeriodReasonFG000FG001
Overall StudyPhysician Decision34
Overall StudyStone migrated from the kidney10

Baseline characteristics

CharacteristicBoston Scientific Navigator HDTotalCook Flexor
Age, Continuous50.4 years
STANDARD_DEVIATION 11
52.1 years
STANDARD_DEVIATION 10
53.1 years
STANDARD_DEVIATION 9
Race and Ethnicity Not Collected0 Participants
Region of Enrollment
United States
47 participants95 participants48 participants
Sex: Female, Male
Female
24 Participants52 Participants28 Participants
Sex: Female, Male
Male
23 Participants43 Participants20 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
0 / 440 / 43
other
Total, other adverse events
0 / 440 / 43
serious
Total, serious adverse events
0 / 440 / 43

Outcome results

Primary

Number of Participants With Successful Sheath Placement

The surgeon documents whether there was Successful placement of sheath (yes or no)

Time frame: One time point - at the beginning of the procedure

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Cook FlexorNumber of Participants With Successful Sheath Placement37 Participants
Boston Scientific Navigator HDNumber of Participants With Successful Sheath Placement39 Participants
Secondary

Ease of Sheath Placement

Surgeons will be asked to subjectively rate the ease of placement on a standardized scale from 0 to 4, 4 being easiest which will be rated by the surgeon who inserted the sheath immediately after placement.

Time frame: One time point - at the completion of the procedure

Population: patients undergoing ureteroscopy with each device.

ArmMeasureValue (NUMBER)
Cook FlexorEase of Sheath Placement2.9 units on a scale
Boston Scientific Navigator HDEase of Sheath Placement3.4 units on a scale
Secondary

Number of Participants With Injury to the Ureter

Subjective rating of damage to ureter. At the completion of the procedure, video of the intraluminal ureter is recorded as the sheath is withdrawn. Videos are analyzed by two blinded staff endourologists who score ureteral injury on a standard 5-point scale (0 to 4); reference Traxer and Thomas.

Time frame: One time point - at the completion of the procedure

Population: Patients undergoing procedures with each device.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Cook FlexorNumber of Participants With Injury to the Ureter36 Participants
Boston Scientific Navigator HDNumber of Participants With Injury to the Ureter27 Participants

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026