Plain English Summary
Background and study aims
Urinary retention is the inability to empty the bladder completely. It is one of the most common complications after surgery and anesthesia. Urination depends on coordinated actions between the bladder muscle and the urethral sphincter muscles. Under the influence of epidural analgesia (pain catheter), patients may not feel the sensation of bladder filling, which can result in urinary retention and bladder damage. Epidural analgesia (pain relief) is provided with local anesthetics that block pain sensation. The anaesthetic drug bupivacaine blocks bladder muscle activity (a motor block), resulting in residual urine remaining in the bladder after urination, which requires monitoring or drainage. The epidural administration of a relatively new anaesthetic drug ropivacaine during labour has resulted in fewer motor blocks. The aim of this study is to find out whether using ropivacaine results in less significant changes in lower urinary tract function than bupivacaine, in patients undergoing renal (kidney) surgery.
Who can participate?
Patients undergoing renal surgery with normal bladder function.
What does the study involve?
Participants will be randomly allocated to receive either ropivacaine or bupivacaine during their surgery. Participants will also undergo tests to assess their bladder function before and after the surgery.
What are the possible benefits and risks of participating?
This study will improve our knowledge of bladder function during epidural analgesia. The immediate benefit to the participants will be that in case of normal bladder function no bladder catheter will be needed, which will reduce the risk of a urinary tract infection, a frequent complication following surgery. Due to the additional bladder tests in this study, there is a slightly increased risk for urinary tract infections. However, all the patients undergoing the bladder tests will receive antibiotics as recommended by the guidelines.
Where is the study run from?
Departments of Anaesthesiology and Urology of the University Hospital Bern (Switzerland).
When is the study starting and how long is it expected to run for?
From April 2015 to April 2017.
Who is funding the study?
University Hospital Inselspital (Switzerland).
Who is the main contact?
PD Dr. med. Patrick Wüthrich
Effects of thoracic epidural administered ropivacaine versus bupivacaine on lower urinary tract function: a randomized controlled study
To evaluate the epidural administration of ropivacaine on lower urinary tract function. The primary hypothesis is that thoracic epidural analgesia (TEA) with the local anesthetics ropivacaine leads to less significant changes in lower urinary tract function than bupivacaine as a control group, in patients undergoing lumbotomy incision for renal surgery.
Kantonale Ethikkommission Bern (KEK BE) (Ethics Committee of Canton Berne), 10/03/2015, ref: 390/14
Randomized parallel-group single-centre interventional assessor-blind trial
Primary study design
Secondary study design
Randomised parallel trial
Patient information sheet
All patients will receive a TEA placed at the insertion site interspace T7-8 or T8-9. Segmental blockade will be achieved using the solutions according to the randomisation.
Group 1: Ropivacaine 2 mg/ml (ROPIVACAIN Sintetica 2 mg/ml ™, Sintetica-Bioren, Couvet, Schweiz)
Group 2: Bupivicaine 1.25 mg/ml (BUPIVACAIN Sintetica 0.125 % ™ (Bupivacain 1.25 mg/ml – Fentanyl 2 µg/ml), Sintetica-Bioren, Couvet, Schweiz)
Ropivacaine , Bupivacain
Primary outcome measures
Post-void residual urine volume (in ml) during thoracic epidural analgesia, measured before surgery (baseline) and on postoperative two or three depending of the patient’s mobility.
Secondary outcome measures
Urodynamic parameters of the storage phase and micturition (e.g. bladder volume at first desire to void, maximum cystometric capacity, bladder compliance, urethral pressure profile, detrusor activity, maximum detrusor pressure, detrusor pressure at maximum flow rate, maximum flow rate, pelvic floor electromyographic activity, incidence of urinary retention). Primary and secondary outcomes will be measured before surgery (baseline) and on postoperative two or three depending of the patient’s mobility. The method used will an urodynamic investigation and secondly assessment of the parameters of the voiding phase. Urodynamic investigations will be performed according to good urodynamic practice. After placement of a 6 French transurethral dual channel catheter and a 14 French rectal balloon catheter (Gaeltec, Dunvegan, Scotland), the bladder will be filled at a rate of 25 to 50 ml/min with Ringer’s lactate solution at room temperature. Parameters of both the storage phase (maximum cystometric capacity, bladder compliance) and voiding phase (detrusor pressure at maximum flow rate [PdetQmax], maximum flow rate [Qmax] and PVR) will be recorded. A TRITON™ multichannel urodynamic system will be used for all measurements (Laborie Medical Technologies Corp., Toronto, Canada). All methods, definitions and units will be in accordance with the standards recommended by the International Continence Society.
Overall trial start date
Overall trial end date
Participant inclusion criteria
1. Written informed consent
2. Kidney surgery
3. Thoracic epidural analgesia
Target number of participants
Participant exclusion criteria
1. Contraindications to epidural analgesia or refusal
2. Preoperative PVR > 100 ml
3. International Prostate Symptom Score (IPSS) > 7
4. Pregnancy (pregnancy test in all women who are not in menopause, exclusion for surgery per se)
Recruitment start date
Recruitment end date
Countries of recruitment
Trial participating centre
University Hospital Bern Inselspital Bern
University Hospital Inselspital
Funding Body Type
Funding Body Subtype
Results and Publications
Publication and dissemination plan
To be confirmed at a later date
Intention to publish date
Participant level data
Not expected to be available
Results - basic reporting