Clinical trial NCT03023488: Effects of Flexible Ureteroscopy on Renal Blood Flow
Official title: Effects Of Flexible Ureteroscopy On Renal Blood Flow
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Circulatory; Change
Keywords: flexible ureteroscopy
blood flow
Lead sponsor: Marmara University
Sponsor class: OTHER
First posted: 2017-01-18
Enrollment: 46
Sex: ALL
Minimum age (years): 18
Maximum age (years): 65
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: NA
Intervention model: SINGLE_GROUP
Primary purpose: DIAGNOSTIC

Brief summary: Aim of this study is to investigate the effects of increased intrarenal pressure during flexible ureteroscopy on renal blood flow.

Patients undergoing flexible ureteroscopy (F-URS) and laser lithotripsy for kidney stones according to European Association of Urology (EAU) guidelines on Urolithiasis will be included in the study after having signed an informed consent form. The pre- and post-operative evaluation and management will be performed according to EAU Guidelines on Urolithiasis. Additionally, as a non-invasive test, bilateral renal power Doppler US will be performed to patients pre- and post-operatively. The pre-operative Doppler US will be performed 2 days prior to surgery and the post-operative Doppler US will be performed in the first 24 hours following surgery. The changes on blood flow in renal artery and arcuate artery will be recorded.

Detailed description: Aim of this study is to investigate the effects of increased intrarenal pressure during flexible ureteroscopy on renal blood flow.

Patients undergoing flexible ureteroscopy and laser lithotripsy for kidney stones according to EAU guidelines on Urolithiasis will be included in the study after having signed an informed consent form. The pre- and post-operative evaluation and management will be performed according to EAU Guidelines on Urolithiasis. Additionally, as a non-invasive test, bilateral renal power Doppler US will be performed to patients pre- and post-operatively. The pre-operative Doppler US will be performed 2 days prior to surgery and the post-operative Doppler US will be performed in the first 24 hours following surgery. The changes on blood flow in renal artery and arcuate artery will be recorded.

Flexible ureteroscopy has been a key component of kidney stone management in the last 20 years. Even for stones larger than 2 cm, flexible ureteroscopy can be performed with high success and low complication rates. Ureteral access sheaths are key contributors to flexible ureteroscopy as they provide easy and repeated access to upper urinary tract and decreased intrarenal pressures due to easy flow back of the irrigation solution.

The increased pressures during flexible ureteroscopy have been an important research area in the last years. Due to irrigation solution and irrigational pumping to provide a clearer vision during flexible ureteroscopy, intrarenal pressures rise and after a certain point pyelo-sinusoidal, pyelo-venous and pyelo-lymphatic backflow starts. It has been shown that this backflow starts when pressure rises above 40 cmH2O (centimeters-water / unit of pressure measurement). Schwalb et al. demonstrated in their study that in kidneys subject to high intrarenal pressure, denudation and flattening of the caliceal urothelium, submucosal edema and congestion are observed. Due to these deleterious effects on urothelium, renal extravasation and bacterial translocation can occur and complications may arise.

Renal Doppler US, due to its non-invasive nature, has been widely used to measure localized blood flow in the kidneys, to evaluate hemodynamic parameters in acute kidney injury. Intrarenal backflow and its consequences such as submucosal edema and congestion may decrease blood flow especially around the calyces subject to high pressures and this situation may result in acute kidney injury.

Eligibility criteria: Inclusion Criteria:

* Patients between ages 18-65
* Patients undergoing flexible ureteroscopy + laser lithotripsy according to EAU Guidelines on Urolithiasis

Exclusion Criteria:

* Pregnant patients
* Patients with already-diagnosed urological malignancies
* Patients ineligible for flexible ureteroscopy due to concomitant co-morbidities

Primary outcomes:
measure: Peak Systolic Velocities (PSV) Measurement by Renal Doppler Ultrasound (US) Examination Evaluating the Effects of Flexible Ureteroscopy (F-URS) on Renal Blood Flow by Demonstrating the Change Between the Pre-operative and Post-operative Parameters.
timeFrame: The doppler examination will be performed 2 days before surgery and the change will be assessed within 1 day of the operation. So, the initial evaluation will be performed and change of values will be assessed 72 hours after the initial evaluation
measure: End Diastolic Velocities (EDV) Measurement by Renal Doppler Ultrasound (US) Examination Evaluating the Effects of Flexible Ureteroscopy (F-URS) on Renal Blood Flow by Demonstrating the Change Between the Pre-operative and Post-operative Parameters.
timeFrame: The doppler examination will be performed 2 days before surgery and the change will be assessed within 1 day of the operation. So, the initial evaluation will be performed and change of values will be assessed 72 hours after the initial evaluation
measure: Resistive Index (RI) Calculation by Renal Doppler Ultrasound (US) Examination Evaluating the Effects of Flexible Ureteroscopy (F-URS) on Renal Blood Flow by Demonstrating the Change Between the Pre-operative and Post-operative Parameters.
timeFrame: The doppler examination will be performed 2 days before surgery and the change will be assessed within 1 day of the operation. So, the initial evaluation will be performed and change of values will be assessed 72 hours after the initial evaluation
measure: Pulsatility Index (PI) Calculation by Renal Doppler Ultrasound (US) Examination Evaluating the Effects of Flexible Ureteroscopy (F-URS) on Renal Blood Flow by Demonstrating the Change Between the Pre-operative and Post-operative Parameters.
timeFrame: The doppler examination will be performed 2 days before surgery and the change will be assessed within 1 day of the operation. So, the initial evaluation will be performed and change of values will be assessed 72 hours after the initial evaluation
Secondary outcomes:
measure: Technical Details - Size of Ureteral Access Sheath
timeFrame: 1 hour after the operation
measure: Technical Details - Name of Flexible Ureteroscope
timeFrame: 1 hour after the operation
measure: Duration of the Flexible Ureteroscopy Operation
timeFrame: 10 minutes after the operation
measure: Operative Characteristics - Irrigation Pressure
timeFrame: 1 hour after the operation
measure: Operative Characteristics - Intraoperative Complications
timeFrame: 1 hour after the operation
measure: Post-Operative Characteristics - Complications
timeFrame: The data will be recorded within 1 month after each procedure.
Other outcomes:
Locations:
Study officials:
affiliation: Marmara University, School of Medicine, Department of Urology
name: Tarik Emre Sener, Urologist
role: PRINCIPAL_INVESTIGATOR
References:
citation: Schwalb DM, Eshghi M, Davidian M, Franco I. Morphological and physiological changes in the urinary tract associated with ureteral dilation and ureteropyeloscopy: an experimental study. J Urol. 1993 Jun;149(6):1576-85. doi: 10.1016/s0022-5347(17)36456-x.
citation: de la Rosette J, Denstedt J, Geavlete P, Keeley F, Matsuda T, Pearle M, Preminger G, Traxer O; CROES URS Study Group. The clinical research office of the endourological society ureteroscopy global study: indications, complications, and outcomes in 11,885 patients. J Endourol. 2014 Feb;28(2):131-9. doi: 10.1089/end.2013.0436. Epub 2013 Dec 17.
citation: Sener TE, Cloutier J, Villa L, Marson F, Buttice S, Doizi S, Traxer O. Can We Provide Low Intrarenal Pressures with Good Irrigation Flow by Decreasing the Size of Ureteral Access Sheaths? J Endourol. 2016 Jan;30(1):49-55. doi: 10.1089/end.2015.0387. Epub 2015 Sep 18.