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Trial registered on ANZCTR


Registration number
ACTRN12610000434099
Ethics application status
Not yet submitted
Date submitted
20/05/2010
Date registered
28/05/2010
Date last updated
28/05/2010
Type of registration
Retrospectively registered

Titles & IDs
Public title
Comparison of 2 lithotripter regarding efficacy / complication rate of kidney and ureteral stones
Scientific title
Modified HM3 versus Modulith SLX-F2 lithotripter: A prospective randomized trial to compare the clinical efficacy and complication rate between the first and the latest lithotriptor generation in patients with kidney and/or ureteral stones.
Secondary ID [1] 251818 0
nil
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Comparison of clinical effectiveness and complication rate of the two above mentioned lithotripter. Study population: Patients with kidney and/or ureteral stones. 257416 0
Condition category
Condition code
Renal and Urogenital 257565 257565 0 0
Other renal and urogenital disorders

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Patients were stratified according to stone location and stone burden. All treatments with either lithotripter took place under anaesthesia (mostly spinal or epidural, few general) to eliminate pain as a limiting factor for optimal treatment and to keep respiratory movements regular for minimal stone movements.
With either lithotripter, treatments were started with a series of 500 shock waves of moderate energy (HM3 with 19kV, SLX-F2 level 7). If the first fluoroscopic control showed no fragmentation, shock wave energy was increased to 21-22 kV or level 9 for HM3 and SLX-F2, respectively. In case of partial stone disintegration after 500 shocks, energy was maintaned in order to prevent unnecessary kidney trauma and progressively decreased (kV by kV / level by level) according to the size of the stone fragments. Treatment was stopped prematurely before the maximally allowed number of shock waves delivered (2500 for kidney stones, 3000 for ureteral stones off the kidney) if the x-ray snap shots didn't allow for the detection of residual fragments. Shocks were delivered heart beat triggered, usually at rates of 70-80 shock waves per minute.
Modified lithotripter HM3, Dornier: The electro-hydraulic shock waves are generated between two electrodes in a water-bath. In an attempt to offer patients anaesthesia-free treatment, the original HM3 was modified in the early 90's. The elllipsoid aperture was increased from originally 15.0cm (aperture area of 176cm2) to 17.2cm (aperture area of 232 cm2) to have the shock wave energy distributed over a larger surface at the skin level. With this, shock waves became also more concentrated in the second focal area with higher peak pressures. Therefore, most modified HM3 with a wider ellipsoid were operated with a reduced generator capacity of 40nF, instead of 80nF as with the original ellipsoid. The HM3 lithotripter used for this trial has the bigger ellipsoid (17.2cm), but still the original generator (capacity =80nF). Exact energy measurements have never been performed for the "hybrid" model but it is estimated to deliver a total energy of at least 45mJ in the focal zone.
Lithotripter Modulith SLX-F2, Storz Medial: The electro-magnetic shock waves are generated in analogy to a loud-speaker. The source aperture is 30cm (aperture area of 707cm2). Of the two focal zones available, we exclusively used the extended focus (F2). Working with a mean energy level 9, total energy in the focal zone is 150mJ. More than 3 times highter than that of the HM3.

Treatment time depends on stone burden and localisation as well as fragmentation. Definitively after 2500 shock waves (kidney) and/or 3000 shock waves (ureter) the treatment has to be finished in order to avoid tissue trauma. The average treatment time is approximately 45-60 minutes. This does not include positioning/monitoring/targegint, which takes another 15-30 minutes.
Intervention code [1] 256519 0
Treatment: Devices
Comparator / control treatment
Control treatment: First generation lithotriptor: Modified HM3 from Dornier. Electro-hgydraulic energy source

Comparator treatment: Third generation lithotriptor: Modulith SLX-F2 from Storz Medical. Electro-magnetic energy source

All treatments with either lithotripter were under anaesthesia (mostly spinal or epidural) to eliminate pain as a limiting factor for optimal treatment. This also keeps respiratory movments on a regular base for minimal stone movements and better targeting. Shock waves were delivered heart beat triggered, usually at rates of 70-80 shock waves per minite. Heart frequencies lower than 60 were accelerated with intravenous atropine whereas for those above 100, analgesia was intensified or treatment interrupted to wait for a spontaneous decrease.
Treatment time depends on stone burden, stone localisation, number of stones, fragmentation etc. Treatment is limited by the maximal number of shock waves allowed to apply (2500 kideny, 3000 ureter)
After randomization, every patient only had one treatment session. Evaluation (disintegration, dilatation, fragment clearance) was performed the day after the treatment. In case of good response with obvious disintegration, a final control took place at 3 months. In doubt, patients were seen after 2 weeks. For those with no or only little effect, a extracorporeal shock wave lithotripsy (ESWL) -retreatment was evaluated thereafter. Every indicated ESWL re-treamtent was performed with the initially assigned lithotriptor. The indication was made by the involved urologist in case of a potential further disintegration benefit. The maximal number of treatments recorded per patient were 3 sessions. Usually, a ESWL re-treatment takes place approx. 2-6 weeks after the initial therapy. Every ESWL treatment is followed by a so called final 3 months control. That is, when the decision about any further intervention versus observation or end of therapy has to be taken.

Besides stone free rate, disintegration/residual fragements, postinterventional (colic) pain, dilatation of the pyelo-caliceal system and fragment clearance, also shock wave energy, number of shock waves applied and fluoroscopy time were compared.
Control group
Active

Outcomes
Primary outcome [1] 258483 0
Stone disintegration, examined by x-ray 1 day and 3 months after ESWL treatment.

Stone disintegration was classified as stone-free, fragments 2mm or less, fragments 2-5mm and fragments greater 5mm. To avoid inter-observer differences, all radiographic studies were interpreted by the same urologist.
Timepoint [1] 258483 0
The degree of stone disintegration/absence of residual fragments were evaluated by plain abdominal film 1 day and 3 months after shock wave therapy. Additional computed tomographies (CT scans) or excretory urographies were used if deemed necessary.
Primary outcome [2] 258514 0
Dilatation of the collecting system, assessed with ultrasound.
Timepoint [2] 258514 0
At 1 day and 3 months after treatment
Primary outcome [3] 258515 0
Complication rate, including: ESWL re-treatments, adjuvant procedures, incidence of hematoma. Recorded prospectively on departmental database.

Hematoma were diagnosed with ultrasound, at the sime time as the upper tract was checked for dilatation.
Timepoint [3] 258515 0
Prospective recording from the day of ESWL treatment to the final control after 3 months or until complete stone clearance was achieved.
Secondary outcome [1] 264272 0
Colic pain, evaluated by questioning the patient (pain present or absent) 1 day and 3 months after ESWL treatment
Timepoint [1] 264272 0
At 1 day and 3 months after treatment.
Secondary outcome [2] 264318 0
Fragment clearance. Urine is filtered during hospital stay. The nurses daily check the result and report findings in the chart. After hospital discharge, the patients continue to filter the urine for another 4 weeks. Eventually filtered stone fragments are brought to the final control after 3 months.
Timepoint [2] 264318 0
Assessment 1 day and 3 months after ESWL treatment (absent or present)
Secondary outcome [3] 264333 0
Number of shock waves and shock wave energy per treatmet.
Timepoint [3] 264333 0
Recorded by the technician after each treatment session and documented in a log book.

Eligibility
Key inclusion criteria
Every patient requiring extracorporeal shock wave lithotripsy after written informed consent.
Minimum age
No limit
Maximum age
No limit
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Patients referred for treatment with HM3. After prior unsuccessful extracorporeal shock wave lithotripsy for the same stone in another hospital. Patients with staghorn calculi or stones with a diameter larger than 30mm. In case of technical problems with the randomly assigned lithotripter on the day of intervention or impossibility to localize the calculus with the randomly assigned lithotripter.
Thrombocytes <100x10/9 per L, prothrombin time < 60%, pregnancy, urinary tract infection, intake of non-steroidal anti-inflammatory drugs within the last 48 hours or ingestion of platelet inhibiting agents within the last 7-10 days.

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Patients with solitary stones were stratified in subcroups according to stone localisation i.e. kidney stones (including upper-, midcalixes and pyelon calculi), ureteral stones and lower calyx stones as well as to stone size (0-10mm, 10-20mm, >20mm). Any patient with more than 1 stone (kidney and/or ureter) even within the same location was assigned to the group with multiple stones and the largest piece was taken to define stone size category.

It was a concealed allocation: After entering the patients data in a central computer, the later assigned the treatment arm according to the above mentioned stratification.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
An external statistican together with our computer specialist developed the program responsible for the randomisation.
=> computerized sequence generation
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Parallel
Other design features
Phase
Phase 4
Type of endpoint/s
Safety/efficacy
Statistical methods / analysis

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
1/04/2006
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
800
Accrual to date
Final
Recruitment outside Australia
Country [1] 2648 0
Switzerland
State/province [1] 2648 0

Funding & Sponsors
Funding source category [1] 257005 0
University
Name [1] 257005 0
Department of Urology
Country [1] 257005 0
Switzerland
Primary sponsor type
University
Name
Department of Urology
Address
University Hospital of Berne
Inselspital
3010 Bern
Country
Switzerland
Secondary sponsor category [1] 256267 0
Hospital
Name [1] 256267 0
Inselspital Bern
Address [1] 256267 0
3010 Bern
Country [1] 256267 0
Switzerland

Ethics approval
Ethics application status
Not yet submitted
Ethics committee name [1] 259058 0
no ethics committee
Ethics committee address [1] 259058 0
This data collection was part of an internal quality control at our hospital comparing two clinically established and approved ESWL treatment devices. Therefore, ethics approval was not required.
Ethics committee country [1] 259058 0
Switzerland
Date submitted for ethics approval [1] 259058 0
01/05/2010
Approval date [1] 259058 0
Ethics approval number [1] 259058 0

Summary
Brief summary
The treatment of urinary stones with extracorporeal shock waves was first described in the early 80's and thereafter almost completely replaced open stone surgery. The first treatement device (lithotriptor) was the HM3 from Dornier. Since then, multiple successor models have been developped and are used worldwide. So far, only few direct comparisons between the first device and a following generation device have been conducted. Owing the last model of such a HM3 device in Switzerland and in addition, a third generation device, we intended to perform an internal quality control. within our department. Both devices are in daily use over years already. In our center, approximately 400 patients are treated per year. The HM3 requires regular technical workup but spare parts are increasingly hard to find. Being aware of the soner or later ending "career" of the legendary HM3, the performed internal quality control will enable us to compare treatment data, e.g. efficacy, complications etc. in the future. We therefore compared the stone free rates, size of residual stone fragments, side effects like hematoma around the kidney, stone clearance (urine was filtered to detect disintegrates), number of shock waves required and re-treatment rates between the two devices.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 31192 0
Address 31192 0
Country 31192 0
Phone 31192 0
Fax 31192 0
Email 31192 0
Contact person for public queries
Name 14439 0
Pascal Zehnder, MD
Address 14439 0
Department of Urology
University Hospital of Bern
Inselspital
3010 Bern

=> actually performing a research fellow ship at the Department of Urology, University of Southern California, Los Angeles, USA
Country 14439 0
Switzerland
Phone 14439 0
US: 001 626 429 1095
Fax 14439 0
Email 14439 0
[email protected]
Contact person for scientific queries
Name 5367 0
Pascal Zehnder, MD
Address 5367 0
Department of Urology
University Hospital of Bern
Inselspital
3010 Bern

=> actually performing a research fellow ship at the Department of Urology, University of Southern California, Los Angeles, USA
Country 5367 0
Switzerland
Phone 5367 0
US: 001 626 429 1095
Fax 5367 0
Email 5367 0
[email protected]

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No Supporting Document Provided



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