Effects of Flexible Ureteroscopy on Renal Blood Flow

NCT ID: NCT03023488

Last Updated: 2018-07-06

Study Results

Results available

Outcome measurements, participant flow, baseline characteristics, and adverse events have been published for this study.

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Basic Information

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Recruitment Status

COMPLETED

Clinical Phase

NA

Total Enrollment

46 participants

Study Classification

INTERVENTIONAL

Study Start Date

2016-02-29

Study Completion Date

2016-12-31

Brief Summary

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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

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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.

Conditions

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Circulatory; Change

Study Design

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Allocation Method

NA

Intervention Model

SINGLE_GROUP

Primary Study Purpose

DIAGNOSTIC

Blinding Strategy

NONE

Study Groups

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Flexible ureteroscopy arm

the findings of patients undergoing flexible ureteroscopy + laser lithotripsy for renal stones according to EAU Guidelines Doppler Ultrasound examination has been performed in the pre-operative and post-operative periods

Group Type EXPERIMENTAL

flexible ureteroscopy

Intervention Type PROCEDURE

Flexible ureteroscopy is an endourological procedure performed for kidney stones. The flexible ureteroscope is a device used to reach the renal cavities through the natural urinary tract in a retrograde fashion. During the operation, irrigation fluid is used to expand the cavities to provide space for movement of the device and also to provide clear vision.

Doppler Ultrasound examination

Intervention Type DEVICE

peak systolic velocities (PSV) and end diastolic velocities (EDV) of the arteries will be measured and then resistive index (RI) and pulsatility index (PI) will be calculated.

laser lithotripsy

Intervention Type DEVICE

The laser fiber extending into the cavities through the working channel of the ureteroscope is used to fragment the stones. Laser energy is generated by the laser machine and transmitted to the stones via the laser fiber.

Interventions

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flexible ureteroscopy

Flexible ureteroscopy is an endourological procedure performed for kidney stones. The flexible ureteroscope is a device used to reach the renal cavities through the natural urinary tract in a retrograde fashion. During the operation, irrigation fluid is used to expand the cavities to provide space for movement of the device and also to provide clear vision.

Intervention Type PROCEDURE

Doppler Ultrasound examination

peak systolic velocities (PSV) and end diastolic velocities (EDV) of the arteries will be measured and then resistive index (RI) and pulsatility index (PI) will be calculated.

Intervention Type DEVICE

laser lithotripsy

The laser fiber extending into the cavities through the working channel of the ureteroscope is used to fragment the stones. Laser energy is generated by the laser machine and transmitted to the stones via the laser fiber.

Intervention Type DEVICE

Eligibility Criteria

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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
Minimum Eligible Age

18 Years

Maximum Eligible Age

65 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

No

Sponsors

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Marmara University

OTHER

Sponsor Role lead

Responsible Party

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Responsibility Role SPONSOR

Principal Investigators

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Tarik Emre Sener, Urologist

Role: PRINCIPAL_INVESTIGATOR

Marmara University, School of Medicine, Department of Urology

References

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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.

Reference Type BACKGROUND
PMID: 8501816 (View on PubMed)

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.

Reference Type BACKGROUND
PMID: 24147820 (View on PubMed)

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.

Reference Type RESULT
PMID: 26381037 (View on PubMed)

Other Identifiers

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09.2016.181

Identifier Type: OTHER

Identifier Source: secondary_id

MAR.UAD.002

Identifier Type: -

Identifier Source: org_study_id

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