Conditions: Urinary Retention Urinary Tract Infections
Keywords: tamsulosin randomized controlled trials as topic double-blind method random allocation placebos Adrenergic alpha-Antagonists urinary retention urinary tract infections urinary catheters catheter-related infections postoperative complications
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 158
Healthy volunteers: no

Brief summary:
The purpose of this study is to determine if tamsulosin ("FLOMAX") is effective in preventing post-operative urinary retention following abdominal surgery. Post-operative urinary retention is a common post-operative complication, occurring in up to 30% of patients undergoing abdominal surgery. It can be described as the inability to initiate urination or properly empty one's bladder following surgery. It is usually self-limited, but it requires the use of catheterization to empty the bladder in order to prevent further injury to the bladder or kidneys and to relief the discomfort of a full bladder. Tamsulosin is a medication that is commonly used in men with urinary symptoms related to an enlarged prostate. There is some evidence to suggest that it may also potentially be beneficial for preventing post-operative urinary retention. Therefore, in this research study, subjects scheduled for abdominal surgery will be randomly assigned to take either tamsulosin once-daily or placebo once-daily for one week leading up to surgery, and up to several days after surgery. Urinary function will be assessed and compared between these two treatments. The hypothesis is that tamsulosin will reduce the rate of postoperative urinary retention compared to placebo.

Detailed description:
Postoperative urinary retention (POUR) complicates up to 30% of general abdominal operations. It results in patient discomfort, embarrassment, interference with therapies, and significant nursing burden. More importantly, urinary retention necessitates use of intermittent catheterization or placement of an indwelling urinary catheter, which exposes the patient to an increased risk of urinary tract infection (UTI), urethral injury, and potentially increased hospital length of stay and cost. For these reasons, a safe and effective intervention for preventing POUR would be highly valuable. Despite such a need, no contemporary studies exist evaluating medications that can be used to prevent POUR in broad general surgery populations. To address this gap, the investigators have designed a prospective, randomized, double-blind, placebo-controlled trial to test the hypothesis that preoperative loading with tamsulosin will prevent POUR in patients undergoing elective, inpatient complex intra-abdominal surgery and thereby lead to improved short-term outcomes.

Tamsulosin is a safe and widely-used selective alpha-1-A adrenergic blocker commonly used for the treatment of lower urinary tract symptoms in men with benign prostatic hypertrophy. It has also been shown to have some benefit in reducing POUR and need for catheterization in men undergoing inguinal hernia repair and other outpatient urologic procedures. This study is a randomized, double-blind, placebo-controlled trial in which patients scheduled for inpatient complex intra-abdominal surgery will be randomized to receive either tamsulosin or placebo for 7 days pre-operatively, and up to several days post-operatively, and then rates of POUR will be compared between the two groups (Aim 1). A retrospective analysis of the data will be used to identify risk factors for POUR and subgroups of patients that would derive the greatest benefit from preoperative tamsulosin (Aim 2). Furthermore, short-term outcomes, including rate of urinary tract infection (UTI) and hospital length of stay, will be compared between the tamsulosin and placebo groups (Aim 3).

Enrolled subjects will be randomized using a blocked, stratified randomization process to either tamsulosin or placebo. Stratification variables include gender, pelvic vs non-pelvic surgery, and International Prostate Symptom Score (IPSS) survey results (which is a measure of baseline lower urinary tract symptoms). After a 7-day treatment period, subjects will undergo surgery as scheduled, and then the assigned treatment will be continued for up to a total of 14 days until the subject either has return of normal voiding function, has required replacement of an indwelling urinary catheter, or is discharged from the hospital.

Arms:
arm 1: None arm 2: None

Interventions: intervention 1: Tamsulosin intervention 2: Placebo
Intervention descriptions: intervention 1: Tamsulosin 0.4mg capsule orally once daily, dosed 30 minutes after dinner or before bed, starting 7 days before surgery and continuing for 0-5 days postoperatively.

Outline of schedule:

* Day 1-7: tamsulosin 0.4mg in the evening
* Day 8: surgery; tamsulosin 0.4mg in the evening if the subject has not yet completed the bladder management protocol
* Day 9-14: tamsulosin 0.4mg in the evening until the subject either 1) completes the bladder management protocol (defined by two consecutive voids with post-void residual \<200mL), or 2) has an indwelling urinary catheter replaced, or 3) is discharged from the hospital, whichever occurs first. The minimum number of total doses is 7; the maximum number of total doses is 14. The 14th dose will be the final dose regardless of bladder function. intervention 2: Placebo capsule orally once daily, dosed 30 minutes after dinner or before bed, starting 7 days before surgery and continuing for 0-5 days postoperatively.

Outline of schedule:

* Day 1-7: placebo in the evening
* Day 8: surgery; placebo in the evening if the subject has not yet completed the bladder management protocol
* Day 9-14: placebo in the evening until the subject either 1) completes the bladder management protocol (defined by two consecutive voids with post-void residual \<200mL), or 2) has an indwelling urinary catheter replaced, or 3) is discharged from the hospital, whichever occurs first. The minimum number of total doses is 7; the maximum number of total doses is 14. The 14th dose will be the final dose regardless of bladder function.

Protocol document:
Prot_SAP_000.pdf: 
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Preoperative tamsulosin for the prevention of postoperative urinary retention: a randomized, 
double-blind, placebo-controlled trial 
 
Principal Investigator:  Evie Carchman, MD 
Phone: (608) 263-2521 
Fax: (608) 265-5963 
 
Sub Investigator: 
Christina Papageorge, MD 
 
General Surgery Research Fellow 
 
Graduate Student, Masters in Clinical Investigation 
 
 
Study Site:   
University of Wisconsin Hospital and Clinics 
 
Department of Surgery  
 
600 Highland Avenue 
 
Madison, WI 53792 
 
 


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Table of Contents 
 
1.0 
Protocol Summary 
2.0 
Introduction 
3.0 
Study Aims 
4.0 
Selection of Study Patients 
5.0 
Research Design and Methods 
6.0 
Registration Procedures 
7.0 
Treatment Plan 
8.0 
Study Parameters 
9.0 
Drug Formulation and Procurement 
10.0 Statistical Considerations 
11.0 Records to be Kept 
12.0 Patient Consent and Peer Judgment 
13.0 Data and Safety Monitoring 
14.0 References 
15.0 Appendix 
 
 


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1.0 PROTOCOL SUMMARY 
 
Postoperative urinary retention (POUR) complicates up to 30% of general abdominal operations.  It 
results in patient discomfort, embarrassment, interference with therapies, and significant nursing 
burden.  More importantly, urinary retention necessitates use of intermittent catheterization or 
placement of an indwelling urinary catheter, which exposes the patient to an increased risk of urinary 
tract infection (UTI), urethral injury, and potentially increased hospital length of stay and cost.  For these 
reasons, a safe and effective intervention for preventing POUR would be highly valuable.  Despite such a 
need, no contemporary studies exist evaluating medications that can be used to prevent POUR in broad 
general surgery populations.  To address this gap, we are designing a prospective, randomized, double-
blind, placebo-controlled trial to test the hypothesis that preoperative loading with tamsulosin will 
prevent POUR in patients undergoing elective, inpatient complex intra-abdominal surgery and thereby 
lead to improved short-term outcomes.   
 
Tamsulosin is a safe and widely-used selective alpha1A adrenergic blocker commonly used for the 
treatment of lower urinary tract symptoms in men with benign prostatic hypertrophy.  It has also been 
shown to have some benefit in reducing POUR and need for catheterization in men undergoing inguinal 
hernia repair and other outpatient urologic procedures.  To test our hypothesis, we will conduct a 
randomized, double-blind, placebo-controlled trial in which we administer tamsulosin or placebo for 7 
days pre-operatively to patients scheduled for inpatient complex intra-abdominal surgery, and then 
compare the rates of POUR in each group (Aim 1).  We also propose a retrospective analysis of our data 
to identify risk factors for POUR and subgroups of patients that would derive the greatest benefit from 
preoperative tamsulosin (Aim 2).  Furthermore, we propose to determine if preoperative tamsulosin 
therapy leads to improved short-term outcomes, including reduced rate of UTI and shorter hospital 
length of stay (Aim 3). 
 
 
2.0 INTRODUCTION 
 
Postoperative urinary retention refers to the inability to void spontaneously or completely following 
surgery.  It complicates up to 69% of operations, depending on the type of surgery, and can have 
significant consequences for the patient.1  The etiology of postoperative urinary retention is likely 
multifactorial, with contributing factors including sympathetic stimulation secondary to pain and 
surgery, local edema, intraoperative bladder distention, patient anxiety, immobilization, damage to 
parasympathetic nerves of the S2 to S4 dermatome, and medication effects.2  It is typically self-limited, 
and is managed with intermittent or indwelling urinary catheterization until resolution.  Multiple risk 
factors for postoperative urinary retention have been identified.  These include opioid use, neuraxial 
anesthesia, type of operation such as anorectal procedures and lower limb joint arthroplasties, older 
age, male gender, and pre-existing lower urinary tract symptoms.2 
 
Although an often underemphasized problem following surgery, postoperative urinary retention occurs 
frequently and can have significant consequences for the patient.  Direct effects of urinary retention 
include patient discomfort, embarrassment, and the consequences of bladder distention such as 
hemodynamic effects (rarely), prolonged detrusor dysfunction, and possible kidney disease.2  Indirect 
effects of urinary retention are a result of the need for catheterization to empty the bladder.  Perhaps 
the most significant of these is catheter-associated urinary tract infection (CAUTI).  UTI is one of the 
most common hospital-acquired infections, and 70-80% of these are associated with an indwelling 


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urinary catheter.3  The most important predictor of CAUTI is duration of catheterization, with an 
estimated 4 to 7% risk of developing bacteriuria for each day of indwelling catheter use.3   Furthermore, 
indwelling catheters cause gross hematuria and urethral stricture in up to 5% and 7%, respectively, of 
patients with short-term indwelling urinary catheters.4  Concentrated efforts to reduce catheter-
associated UTI invariably involve early removal of indwelling urinary catheters (IUC).  However, in order 
to facilitate early catheter removal without a large associated risk of catheter reinsertion, targeted 
efforts must be made to reduce the risk of urinary retention. 
 
Tamsulosin is a selective alpha-1A adrenoreceptor antagonist that has been demonstrated to be 
effective in treating lower urinary tract symptoms in men with benign prostatic hypertrophy.5  
Furthermore, it is a safe and well-tolerated medication with more minimal cardiovascular effects than 
other less-selective alpha blockers.5  It is thought to relieve lower urinary tract symptoms by relaxation 
of the smooth muscle present in the bladder neck, urethral sphincter, and prostate.  Tamsulosin has 
been studied previously in surgical patients, and was found to reduce the rate of POUR from 21.1% 
(placebo) to 5.9% in men undergoing varicocelectomy, inguinal hernia repair, and scrotal surgery.6  
It has not previously been studied in broad general surgery populations, and has not been dosed more 
than approximately 24 hours pre-operatively.  Steady-state concentration of tamsulosin is not achieved 
until the fifth day of once-daily dosing, which the rationale for the longer preoperative treatment 
duration this this study. 
 
In summary, POUR is a common, and not inconsequential, complication following general surgery 
procedures.  In particular, it results in the need for catheterization, exposing the patient to all of the 
concomitant risks.  Therefore, the ability to prevent urinary retention, thereby mitigating the need for 
catheterization, would provide significant benefit to surgical patients. 
 
 
3.0 STUDY AIMS 
 
In this study, we will test the hypothesis that preoperative loading of the alpha-adrenergic receptor 
inhibitor tamsulosin will decrease the incidence of postoperative urinary retention in patients 
undergoing elective complex intra-abdominal surgery, thereby also decreasing the rate of UTI and 
hospital length of stay.  To test this hypothesis, we will accomplish the following aims: 
 
3.1 Specific Aim 1:  Determine if tamsulosin administered preoperatively and perioperatively is 
more effective than placebo in preventing postoperative urinary retention in patients 
undergoing elective, inpatient, complex intra-abdominal surgery. 
 
We hypothesize that patients treated with tamsulosin for 7 days preoperatively and 
immediately postoperatively will have a lower incidence of postoperative urinary retention and 
need for catheterization compared to those patients treated with placebo.  To test this 
hypothesis, we will investigate the following sub-aims: 
 
3.1.1 
Aim 1a.  Determine the frequency of postoperative urinary retention in each group, 
as defined by need for at least a single intermittent catheterization after surgery or 
following the removal of IUC. 
 


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3.1.2 
Aim 1b.  Measure the ability to spontaneously and completely void in patients after 
the removal of IUC by measuring time until first void, post void residual urine 
volume, and number of intermittent catheterizations. 
 
3.1.3 
Aim 1c.  Determine the rate of IUC replacement. 
 
3.1.4 
Aim 1d.  Measure frequency of adverse effects of tamsulosin therapy. 
 
3.2 Specific Aim 2:  Identify risk factors for postoperative urinary retention based on preoperative 
characteristics and type of operation, and identify which patient population benefits the most 
from preoperative tamsulosin therapy.  
 
We hypothesize that there are identifiable patient- and operation-related characteristics that 
can predict postoperative urinary retention.  In testing this hypothesis, the following two sub-
aims will be investigated: 
 
3.2.1 
Aim 2a.  Determine what preoperative patient characteristics and operative 
characteristics predict postoperative urinary retention. 
 
3.2.2 
Aim 2b.  Determine which subgroup of patients derives the greatest benefit from 
preoperative tamsulosin therapy. 
 
3.3 Specific Aim 3: Determine if preoperative tamsulosin therapy results in improved short-term 
outcomes.   
 
In this aim, we will test the hypothesis that reducing the rate of postoperative urinary retention 
leads to decreased rate of UTI and decreased hospital length of stay.  We therefore propose the 
following sub-aims: 
 
3.3.1 
Aim 3a.  Compare and contrast rates of postoperative UTI in patients randomly 
assigned to tamsulosin therapy compared to those in the placebo arm. 
 
3.3.2 
Aim 3b.  Determine postoperative length of stay in the two groups of patients. 
 
3.4 Endpoints 
 
3.4.1 
Primary endpoint 
 
3.4.1.1 Need for any intermittent catheterization after initial IUC removal 
 
3.4.2 
Secondary endpoints 
 
3.4.2.1 Need for replacement of IUC 
3.4.2.2 Adverse events of tamsulosin and placebo 
3.4.2.3 Time from catheter removal, last intermittent catheterization (if performed in 
the operating room or post-anesthesia care unit), or departure from operating 
room (if no IUC) until first spontaneous void 


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3.4.2.4 Total number of intermittent catheterizations required per subject 
3.4.2.5 Post void residual urine volume after first spontaneous void, as measured by 
bladder scanning 
3.4.2.6 Need for discharge from the hospital with an IUC 
3.4.2.7 Urinary tract infection diagnosed within 30 days of operation 
3.4.2.7.1 
Defined as a symptomatic, culture-confirmed UTI with >105 CFU with a 
single pathogen if diagnosed while inpatient 
3.4.2.7.2 
Defined as a subject self-reported, clinician-diagnosed UTI (if diagnosed 
as an outpatient or at another facility)—to be collected over the phone 
at 30 day follow up contact with subject 
3.4.2.8 Hospital length of stay in days 
 
 
4.0 SELECTION OF PATIENTS 
 
4.1 Study population 
 
Patients will be identified from the general surgery clinics at the University of Wisconsin Hospital 
and Clinics (UWHC), UW Digestive Health Center (UW DHC), The American Center (TAC), and the 
UW East Clinic.  This includes patients who are being evaluated and worked up for surgery.   
 
4.2 Eligibility Criteria 
 
4.2.1 
Inclusion Criteria 
 
Patients must be 18 years of age or older, English-speaking, able to provide 
informed consent, and scheduled to undergo an elective, complex intra-abdominal 
operation with a planned postoperative inpatient stay of at least 1 night.  Eligible 
operations will include any of the following operations approached via any 
operative approach (i.e. open, laparoscopic, hand-assisted laparoscopic, single-
incision laparoscopic, or robotic): 
 
4.2.1.1 Partial colectomy 
4.2.1.2 Total abdominal colectomy 
4.2.1.3 Proctocolectomy 
4.2.1.4 Low anterior resection 
4.2.1.5 Abdominoperineal resection 
4.2.1.6 Restorative proctocolectomy/IPAA 
4.2.1.7 Proctopexy (transabdominal) for prolapse 
4.2.1.8 Intestinal stricturoplasty 
4.2.1.9 Lysis of adhesions 
4.2.1.10 End or diverting colostomy reversal 
4.2.1.11 Ileostomy reversal 
4.2.1.12 Closure of enterocutaneous, enteroenteric, or enterocolic fistula 
4.2.1.13 Partial or complete gastrectomy 
4.2.1.14 Small bowel resection 
4.2.1.15 Small bowel diversion/ostomy 


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4.2.1.16 Large bowel diversion/ostomy 
4.2.1.17 Pancreaticoduodenectomy 
4.2.1.18 Pancreatectomy 
4.2.1.19 Hepatectomy 
4.2.1.20 Gastric bypass 
4.2.1.21 Sleeve gastrectomy 
4.2.1.22 Nissen/Dor/Toupet fundoplication 
4.2.1.23 Transabdominal adrenalectomy 
4.2.1.24 Splenectomy 
4.2.1.25 Complex abdominal wall hernia repair (i.e. Rives-Stoppa type repair, large 
laparoscopic ventral hernia repair) 
4.2.1.26 Exploratory laparotomy 
4.2.1.27 Other comparable complex intra-abdominal operations  
 
4.2.2 
Exclusion Criteria 
 
4.2.2.1 Less than age 18 
4.2.2.2 Allergy or contraindication to tamsulosin 
4.2.2.3 Serious sulfa allergy 
4.2.2.4 Current use of alpha blocker (alfuzosin, doxazosin, prazosin, silodosin, terazosin, 
verapamil, tamsulosin, phenoxybenzamine) or oral alpha agonist (midodrine) 
4.2.2.4.1 
Initiation of one of these medications during the intervention phase of 
the study will result in subject withdrawal from the study. 
4.2.2.5 Current warfarin use 
4.2.2.6 Pre-existing indwelling urinary catheter, suprapubic catheter, or urostomy 
4.2.2.7 End stage renal disease or dialysis-dependence 
4.2.2.8 Sitting systolic blood pressure in the upper extremity of less than 100mmHg at 
time of eligibility screening 
4.2.2.9 Presence of orthostatic hypotension at the time of eligibility screening 
4.2.2.9.1 
Orthostatic hypotension is defined as a drop in systolic blood pressure 
of 20mmHg from sitting to standing, or drop in diastolic BP of 10 mmHg 
from sitting to standing after 2-3 minutes of standing after being in a 
sitting position 
4.2.2.10 
Anticipated inability to take oral medications on post-operative day #0 
4.2.2.11 
Anticipated requirement for IUC beyond post-operative day #2  
4.2.2.12 Non-English speaking 
4.2.2.13 Pregnant or breast-feeding 
4.2.2.14 Unwillingness to answer all 7 questions on the IPSS survey 
4.2.2.15 Lacking capacity to provide informed consent 
 
 


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5.0 RESEARCH DESIGN AND METHODS 
 
5.1 Collaborating sites   
 
There are no collaborating sites.  Patients will be identified from the general surgery clinics at 
UWHC, the UW DHC, The American Center (TAC), and UW East Clinic.  All patients enrolled in 
the study will undergo surgery at, and be admitted to, UWHC.   
 
5.2 Data extraction from medical record 
 
The following information will be extracted from the subject’s medical record at the time of 
preoperative visit, following enrollment in the study:  date of birth, age, gender, race, height, 
weight, information about planned surgery, co-morbidities, past medical history, past surgical 
history, current medications, allergies, and smoking history.  Additional data extracted from the 
subject’s medical record following their operation includes: operation performed, length of 
operation (minutes), type of anesthesia (general, regional, MAC, local), volume of intravenous 
fluids administered intra-operatively, estimated blood loss, placement of epidural, type of 
anesthetic medications used, placement/removal of IUC in the operating room, volume of urine 
output in the operating room, and whether or not straight catheterization was performed at the 
conclusion of the case in the operating room. 
 
Data to be extracted from the medical record following discharge from the hospital includes: 
hospital length of stay (days), whether or not the subject was discharged with an indwelling 
catheter, diagnosis of urinary tract infection within 30 days of operation, and urine culture data 
if applicable.   
 
All of the data extracted from a subject’s medical record will be entered into the ICTR OnCore 
Clinical Research Management System. 
 
5.3 Data collection 
 
At the time of the pre-operative visit, following enrollment in the study, subjects will fill out the 
International Prostate Symptom Score (IPSS) Survey.  This survey is a validated, self-
administered 7-item questionnaire that assesses obstructive lower urinary tract symptoms.  
Additionally, subjects will be administered a questionnaire that asks about history of prior 
problems with urinary retention and prior urinary tract surgeries or procedures, consisting of a 
total of 3 questions.  Subjects may decline to  answer the survey questions on the IPSS survey, 
but this will result in ineligibility for the trial, as IPSS score is a stratification variable for 
randomization.  Subjects may skip the urinary tract surgery/history questions if they feel 
uncomfortable or embarrassed, and this will not result in exclusion from the study. Case report 
forms (CRFs) will be utilized to collect data prospectively during the subject’s postoperative 
course while inpatient.  This data will be collected by a study team member, and will include 
time of arrival and departure from the operating room, time of first void, date/time of IUC 
removal, date/time of first void after catheter removal, first post-void residual volume, 
date/time of first straight catheterization (if applicable), date/time of all subsequent straight 
catheterizations (if applicable), date/time of IUC replacement (if applicable), and date/time of 
the first two adequate voids (if applicable).  Finally, subjects will be contacted by telephone 30-


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40 days after the date of surgery to ask if they have been treated for a urinary tract infection 
since discharge from the hospital (in order to capture UTIs that are diagnosed outside of our 
hospital system).   Additionally, data regarding adverse events will be collected using an Adverse 
Event Log.  A study team member will make contact with the subject at two separate time 
points to inquire about adverse events: 1) on the day of surgery (in person, in the hospital), and 
2) postoperatively via telephone call 30-40 days after surgery.  Additionally, adverse events will 
be abstracted from the electronic medical record during the immediate postoperative period.  
AEs occurring following surgery up until 48 hours after discontinuing study drug will be 
abstracted from the subject’s EMR.  
 
5.4 Confidentiality protections, sharing of data, disposition of data 
 
Subjects enrolled in the study will be sequentially assigned a unique 3-digit study identification 
number, which will be used to identify the subject throughout the course of the study.  The link 
between the subject’s identifiers (i.e. name, MRN, birthdate) and the subject ID will be available 
in the OnCore system. All data exported from the system will only contain the Subject ID 
number, and will not contain other subject identifiers. 
 
All paper forms containing subject information or data will be kept locked in the offices of the PI 
or study coordinator. 
 
5.4.1 
ICTR OnCore Clinical Research Management System 
 
This study will utilize the clinical research management software, Online 
Collaborative Research Environment (OnCore), adopted by the School of Medicine 
and Public Health (SMPH) and available to all researchers conducting clinical 
research studies. The instance of OnCore that will be utilized for this study is 
supported and managed by the UW Institute for Clinical and Translational Research 
(ICTR). OnCore-CRM has been, and continues to be deployed nationally at multiple 
academic medical centers, some of which are NIH Clinical and Translational Science 
Award (CTSA) sites including UW ICTR, and is an extension of technology currently 
used in more than two dozen Cancer Centers around the country.  
 
ICTR OnCore is a sophisticated, web-based data management system that: a) 
ensures secure, easy data entry at multiple sites; b) integrates multiple data sources 
such as individual studies and patient registries; c) provides controlled, secure 
access to sensitive data using role-based access control; d) provides workflow 
automation; and e) allows export and reporting of data for Data and Safety 
Monitoring Boards and biostatisticians.  
 
This software provides protocol management functions (e.g. subject scheduling; 
screening, data organization), maintains updated forms, addresses budget 
development, billing, and fiscal management, generates summary reports, and 
provides essential links with other research administration and electronic medical 
records systems. ICTR OnCore eases the burden of the individual researcher and 
unifies protocol management within research programs and including researchers at 
multiple sites, enhancing protocol integrity and regulatory compliance efforts.  


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Current Status: Both UW ICTR and SMPH are committed to the use of ICTR OnCore 
on an enterprise-wide scale. ICTR OnCore completed the initial pilot phase in 2009 
and has been fully implemented for all clinical research groups across the 
infrastructure. Many workflows and processes have been identified and 
standardized within ICTR OnCore for use across the spectrum. 
 
ICTR OnCore-CRM is hosted by the UW School of Medicine and Public Health 
(SMPH) Information Technology (IT) Office on its server farm with redundant 
systems at two, environments are maintained for production, training, and testing. 
The application-programming model employed in ICTR OnCore-CRM conforms to 
the Java 2 Platform, Enterprise Edition (J2EE) standard for web-based applications. 
J2EE is a widely accepted standard for developing multi-tier enterprise applications 
and is based on standardized, modular components. The J2EE standard includes 
compliance tests to ensure portability of applications. In addition to portability, J2EE 
provides a JDBC API for database access and a proven security model that is 
applicable to Internet applications. J2EE also supports Enterprise JavaBeans 
components, Java Servlets API, JavaServer Pages, and XML technology. The ICTR 
OnCore-CRM application uses these, Apache Web services, and an application 
server (JBoss/TomCat). The backend is an Oracle® relational database management 
system maintained by SMPH IT. Both the database and application servers are 
behind a firewall maintained by SMPH IT staff. Several complete environments are 
maintained for production, training, testing, and validation.  This provides for a high 
level of system security and reliability. 
 
The data collected during the course of the study will be stored in OnCore.  
However, as is necessary for the completion of remote data analysis and travel 
to/from conferences where data may be presented, data exported from OnCore 
may be transferred to a limited number of password-protected and encrypted 
laptops belonging to study staff as necessary.  In this case, data would be stored on 
a password protected and encrypted USB drive in order to transfer data to the 
laptop.  Laptops and USB drives will only contain data that has been exported from 
OnCore and containing only Subject ID number without associated subject 
identifiers.  Only study staff will have access to such USB drives and laptops.  
Laptops and USB drives will not contain the key to the code. 
 
The clinical research pharmacy will maintain the randomization code sheet, and this 
will not be made accessible to other study team members until completion of the 
study (or at interim data and safety monitoring analysis).  Unblinding at interim data 
analysis will only occur for subjects whose data collection is complete. 
 
5.5 Sub-studies/correlative studies 
 
The data collected during this study will be used to retrospectively identify risk factors that are 
associated with urinary retention as described in Specific Aim 2.  This analysis will be performed 
both on the placebo treated group alone and the overall study population.  Logistic regression 
will be used for this analysis.  The response variable will be the primary endpoint (need for any 


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intermittent catheterization).  The various preoperative and operative variables collected during 
the study will be used as predictor variables in this analysis.     
 
5.6 Timeline 
 
5.6.1 
Screening for eligibility 
 
Pre-screening of general surgery clinic patients will occur prior to initial contact.  If a 
patient is found to be eligible on pre-screening and upon contact has expressed 
interest in learning more about the study, then formal screening for eligibility will 
occur after informed consent is obtained.  If the subject is determined to be 
potentially eligible based on the gross eligibility criteria reviewed during the pre-
screening process, the subject will be invited to learn more about the study. If the 
patient is interested in participating in the study at that time, the enrollment 
protocol, including obtaining informed consent, will be initiated.  If the patient has 
another scheduled preoperative visit that will occur more than one week prior to 
their scheduled surgery date, then the informed consent and enrollment procedures 
may be deferred until the next visit.  Likewise, if the patient does not have another 
preoperative clinic visit appointment scheduled, but would like more time to make a 
decision about participation in the study, arrangements will be made for future 
follow up with a study team member as described below. 
 
5.6.2 
Consent/Enrollment/Baseline 
 
After the pre-screening procedures determine the subject may be potentially 
eligible, and the subject has expressed an interest in participating in the study, we 
will proceed with the informed consent process (either at the initial or subsequent 
preoperative clinic visit).  As part of formal screening for eligibility, all women of 
childbearing age and potential will be given a pregnancy test.  Upon completion of 
the screening procedures, and determination that the subject is eligible to 
participate, the individual will be considered enrolled in the study. Due to 
constraints of the study related to the medication starting 7 days preoperatively, 
consent and enrollment must be completed at least 7 days prior to the scheduled 
surgery.  If after the initial clinic visit, the patient has another scheduled 
preoperative clinic visit prior to 7 days preoperatively, then the patient will be given 
the opportunity to take the consent form home if they so desire, and then signed 
informed consent will be obtained at the next clinic visit if applicable.  If, however, 
the patient does not have an additional preoperative clinic visit scheduled and 
needs additional time to consider participation in the study, he or she may bring 
written materials home and study personnel will follow up via telephone call.  If the 
patient is interested in participating in the study, then a visit will be arranged with 
the study coordinator (prior to 7 days preoperatively) for the patient to sign the 
consent form, undergo formal eligibility screening, and complete enrollment. 
 
After enrollment, the subject will fill out the first data collection form, which 
includes the IPSS survey and questionnaire regarding history of previous urinary 
retention and urinary tract surgery or procedures.  The subject may choose to 


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decline to answer any of the IPSS survey questions, however, this will result in 
exclusion from the study, as IPSS score is being used for stratification in the 
randomization process.  Following completion of the IPSS survey, the subject will be 
randomized by the clinical research pharmacy.  The subject will be given a 14-day 
supply of tamsulosin or placebo, according to randomization, along with instructions 
for taking the medication. 
 
5.6.3 
Treatment period 
 
Treatment will start 7 days prior to scheduled surgery and will continue post-
operatively for up to 7 days while the subject is still in the hospital (for a total of 14 
doses).  A member of the study team will contact the subject via telephone as a 
reminder on the day that treatment is to be initiated.  If a subject discontinues study 
treatment (chooses to withdraw from the study) prior to their scheduled surgery, 
the subject will be discontinued and replaced, and reason for withdraw from study 
will be noted.  Data will continued to be collected for these subjects and their data 
will be included on an intent-to-treat basis, but they will be replaced for sample size. 
If the subject discontinues study drug any time after their surgery, the subject will 
be followed with intent to treat and will not be replaced.  If a subject’s planned 
surgery is postponed PRIOR to initiation of treatment but is rescheduled to within 
30 days of when the subject was randomized, then the subject may stay enrolled in 
the trial, will keep their same treatment assignment, and will be given a new start 
date for treatment (7 days before their rescheduled surgery date).  If, however, the 
surgery is postponed or cancelled AFTER initiation of treatment, then the subject 
will be taken off treatment and discontinued from the study.  If the subject has not 
yet initiated treatment and their surgery is rescheduled to a date that is more than 
30 days from the date of randomization, the subject will be discontinued.   
 
Once a subject completes the bladder management protocol (is voiding 
spontaneously and completely—specifically, 2 consecutive voids with PVR less than 
200mL) OR requires replacement of an IUC, the treatment will be discontinued 
within 24 hours, and the protocol is complete.  The protocol may be completed as 
early as POD#0.  The maximum number of days of treatment will be 14 (up until 
POD#6, i.e. last dose given in the evening of POD#6).  No subjects will be discharged 
from the hospital on study medication. 
 
5.6.4 
Follow-up 
 
A member of the study team will contact the subject via telephone approximately 
30-40 days after surgery to ask about adverse events and to inquire about urinary 
tract infection and voiding problems.  Subjects will be asked about diagnosis of 
urinary tract infection since leaving the hospital, and chart review will be performed 
by study personnel to ascertain the diagnosis of urinary tract infection.   
 
As part of standard of care, most subjects will also have a scheduled post-operative 
follow up visit in the General Surgery clinic with their surgeon, usually 2-3 weeks 
following the date of surgery.  In general, if a patient is discharged from the hospital 


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with an IUC, it is standard to have the patient follow up in the Urology Voiding 
Clinic; however, this would be outside of the scope of this study protocol.   
 
5.6.5 
Final study encounter 
 
The final study encounter will be the follow up phone call on or around post-
operative day #30 for all subjects (30-40 days after surgery).  A study team member 
will contact the subject via telephone to ask if he/she has been treated for a urinary 
tract infection since discharge from the hospital (in order to capture UTIs treated 
outside of the UW system), and to inquire about adverse events since discharge 
from the hospital. 
 
5.6.6 
Early termination visit 
 
If a subject wishes to terminate their enrollment in the study early, no visit will be 
required, and this decision will have no bearing on the individual’s clinical care.  If 
enrollment is terminated after surgery, then the subject will not be replaced. If 
enrollment is terminated prior to surgery, the subject will be replaced.        
 
 
6.0 REGISTRATION PROCEDURES 
 
All subjects will be registered prior to beginning the protocol treatment.  The following information 
will be included in registration: 
 
Subject name, address, telephone number, birth date, sex, race 
Primary disease site, planned operation 
Date on study 
Date randomized 
Staff physician 
Protocol number 
 
 
7.0 TREATMENT PLAN 
 
7.1 Administration Schedule 
 
7.1.1 
Treatment ARM A—tamsulosin: 
 
Tamsulosin 0.4mg capsule orally one time per day, to be taken 30 minutes after 
dinner or before bed starting 7 days before surgery and continuing for 0-6 days 
post-operatively.  Outline of schedule: 
 
Day 1: tamsulosin 0.4mg in the evening 
Day 2: tamsulosin 0.4mg in the evening 
Day 3: tamsulosin 0.4mg in the evening 
Day 4: tamsulosin 0.4mg in the evening 


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Day 5: tamsulosin 0.4mg in the evening 
Day 6: tamsulosin 0.4mg in the evening 
Day 7: tamsulosin 0.4mg in the evening 
Day 8: surgery 
Day 8: tamsulosin 0.4mg in the evening (same day as surgery) if the subject has 
not yet completed the bladder management protocol 
Day 9-14: tamsulosin 0.4mg in the evening until up to 24 hours after the subject 
has an indwelling urinary catheter replaced (at which time the protocol stops) or 
the subject completes the bladder management protocol (has voided twice 
consecutively with a post-void residual <200mL).  The minimum number of total 
doses is 7; the maximum number of total doses is 14.  The 14th dose will be the 
final dose regardless of bladder function.  No subjects will be discharged from the 
hospital on study medication. 
 
7.1.2 
Treatment ARM B—placebo: 
 
Placebo capsule orally dosed exactly as outlined above for Treatment ARM A 
 
7.2 Adverse Event Reporting Requirements 
 
An adverse event log will be maintained for each enrolled subject.  Adverse event screening will 
occur at three time points: 1) on the day of surgery either pre- or post- operatively (in person, in 
the hospital, via interview of the subject by a study team member), 2) during the postoperative 
period for the period from surgery until 48 hours after completion of the intervention (via 
abstraction of AEs from the subject’s EMR), and 3) 30-40 days after surgery (via telephone 
interview of the subject by a study team member).  Safety data will be monitored and analyzed 
by an external Data Monitoring Committee (through ICTR), and unanticipated problems or 
complications will be reported to the IRB per its reporting guidelines.  Unexpected or severe 
adverse events will also be reported to the PI within 72 hours of identification. 
 
7.3 Dose Modifications 
 
Dose modifications will not be made in this study.  If a subject has an intolerable adverse event 
or side effects related to the study treatment, the drug will be discontinued and the subject will 
be removed from the protocol.  Follow up outcome data will still be collected to allow for intent-
to-treat analysis.   
 
7.4 Supportive Care 
 
All supportive measures consistent with optimal patient care will be given throughout the study.   
 
7.5 Duration of Therapy 
 
Treatment will be discontinued within 24 hours of the subject’s completion of the bladder 
management protocol with return of normal bladder function (2 consecutive voids with PVR less 
than 200mL) or requirement of IUC re-insertion for urinary retention.  The maximum number of 
doses (days) of treatment is 14.  If ongoing urinary retention is present, further management 


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will be deferred to the treating physician team.  This sometimes involves initiation of a short 
course of alpha-blockers in conjunction with IUC, followed by a spontaneous voiding trial. 
 
 
8.0 STUDY PARAMETERS 
 
Component 
Description 
Timing 
Contact points 
Pre-screening for 
eligibility 
The electronic medical 
records of prospective 
subjects will be pre-
screening for eligibility 
by a study team 
member. 
After the patient is 
scheduled in the 
general surgery clinic, 
prior to actual 
appointment. 
Study team 
member 
Invitation to participate 
in study 
If the patient is eligible 
based on pre-
screening, the patient 
will be informed about 
the study and asked 
about interest in 
participating. 
At initial or subsequent 
pre-operative general 
surgery clinic 
appointment 
Surgeon, 
resident, nurse 
practitioner, or 
study team 
member 
Informed consent 
If the patient is eligible 
for the study, he/she 
will be given a copy of 
the informed consent 
and the informed 
consent process will 
occur. 
Either initial pre-
operative clinic visit, or 
subsequent pre-
operative clinic visit if 
scheduled more than 1 
week prior to the date 
of surgery 
Surgeon, 
resident, or study 
team member 
Formal screening for 
eligibility 
The Eligibility Checklist 
will be completed by a 
study team member 
with the patient.  
Includes pregnancy test 
in women of 
childbearing age and 
potential. 
At initial or subsequent 
pre-operative general 
surgery clinic 
appointment 
Study team 
member 
Enrollment 
Enrollment in the study 
and registration. 
After informed consent 
process at preoperative 
clinic visit. 
Study team 
member 
IPSS Survey (R) 
Validated survey of 
lower urinary tract 
symptoms to be 
completed by the 
subject 
Pre-operative clinic 
visit, after enrollment 
Study team 
member  


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Component 
Description 
Timing 
Contact points 
Urinary history 
questionnaire (R) 
Short questionnaire (3 
questions) regarding 
history of urinary 
retention and prior 
urinary tract surgery or 
procedures 
Pre-operative clinic 
visit, after enrollment 
Study team 
member 
Randomization 
Random allocation by 
the PRC to either the 
tamsulosin group or 
the placebo group 
Preoperative clinic visit, 
after enrollment. 
PRC 
Reminder phone call 
(R) 
Phone call or text 
message from study 
personnel to subject on 
Study day 1 to remind 
subject to start taking 
the drug/placebo 
Study day 1 
Study team 
member 
Pre-operative 
treatment with study 
drug (R) 
Dosing of tamsulosin or 
placebo as described in 
section 7.1 
Study days 1-7 
Subject to self-
administer at 
home 
Screening for adverse 
events, time 1 of 3 
Study personnel will 
ask subject about 
treatment-emergent 
adverse events 
occurring during the 
preoperative phase of 
intervention 
Study day 8, pre or post 
operatively 
Study team 
member 
Operation (SOC) 
Elective inpatient 
complex intra-
abdominal surgery as 
scheduled 
Study day 8 
Surgeon 
Post-operative 
treatment with study 
drug (R) 
Dosing of tamsulosin or 
placebo as described in 
section 7.1  
Study days 8-14, or 
discontinued prior to 
day 14 based on 
completion of bladder 
management protocol 
or re-insertion of IUC 
Administered by 
subject’s RN 
Bladder management 
protocol (see appendix) 
(SOC) 
Monitoring of bladder 
volume via supra-pubic 
ultrasound, 
measurement of post-
void residual volume, 
intermittent 
catheterization as 
needed 
Postoperatively, while 
inpatient (Days 8-14) 
Subject’s RN 
Screening for adverse 
events, time 2 of 3 
Study personnel will 
perform review of the 
From day of surgery 
until 48 hours after  
Study team 
member 


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Component 
Description 
Timing 
Contact points 
EMR to abstract AEs 
occurring during the 
postoperative phase of 
intervention 
completing the 
intervention 
Final study visit (R) 
Telephone call to 
subject by study team 
personnel 
30-40 days after 
surgery 
Study team 
member 
Screening for adverse 
events, time 3 of 3 (R) 
Study personnel will 
ask subject about 
treatment-emergent 
adverse events 
occurring during the 
post-intervention 
phase of trial (up to 30 
days after surgery)  
30-40 days after 
surgery via telephone 
call, will be combined 
with inquiry about UTI 
(see below) 
Study team 
member 
Inquiry about diagnosis 
of UTI (R) 
Telephone call to 
patient 30 days after 
surgery to inquire 
about whether the 
patient has been 
treated for a UTI since 
surgery; chart review 
for UTI diagnosis within 
our institutional EMR 
30-40 days after 
surgery via telephone 
call (will be combined 
with above phone 
call)/chart review 
Study team 
member 
 
 
9.0 DRUG FORMULATION AND PROCUREMENT 
 
9.1 Tamsulosin hydrochloride (NDC 0597-0058-01) 
 
9.1.1 
Other names:  FLOMAX 
 
9.1.2 
Classification: alpha1A adrenoceptor antagonist 
 
9.1.3 
Mode of Action:  Tamsulosin works by blocking alpha1A adrenergic receptors in the 
prostate, prostatic urethra, and bladder neck, which results in relaxation of the 
smooth muscles in the bladder neck and prostate, thereby reducing bladder outlet 
obstruction. 
 
9.1.4 
Storage and stability 
 
Stored at 25 degrees Celsius (77 degrees F); excursions permitted to 15 degrees C to 
30 degrees C (59 degrees F to 86 degrees F) 
 
9.1.5 
Dose specifics: 0.4mg orally dosed one time per day, 30 minutes after a meal, in the 
evening 


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9.1.6 
Preparation: capsule 
 
9.1.7 
Route of administration: orally; capsules should not be crushed, chewed, or opened 
 
9.1.8 
Incompatibilities 
 
9.1.8.1 Other alpha-adrenergic blockers 
 
Per package insert: “The pharmacokinetic and pharmacodynamic interactions 
between FLOMAX capsules and other alpha-adrenergic blocking agents have not 
been determined. However, interactions may be expected and FLOMAX 
capsules should NOT be used in combination with other alpha-adrenergic 
blocking agents.”  Patients taking concomitant alpha blockers (including 
verapamil, which has alpha blockade action at therapeutic doses) will be 
excluded from the study. 
 
9.1.8.2 Cimetidine 
 
Per package insert: “The pharmacokinetic interaction between cimetidine and 
FLOMAX capsules was investigated. The results indicate significant changes in 
tamsulosin HCl clearance (26% decrease) and AUC (44% increase). Therefore, 
FLOMAX capsules should be used with caution in combination with cimetidine, 
particularly at doses higher than 0.4 mg.”  Patients taking cimetidine will still be 
eligible for the study, but will be notified about potential increased risk of side 
effects.   
 
9.1.8.3 Warfarin 
 
Per package insert: “A definitive drug-drug interaction study between 
tamsulosin hydrochloride and warfarin was not conducted. Results from limited 
in vitro and in vivo studies are inconclusive.  Therefore, caution should be 
exercised with concomitant administration of warfarin and FLOMAX capsules.”  
We will exclude patients taking warfarin.  
 
9.1.8.4 Strong inhibitors of CYP3A4 (boceprevir, clarithromycin, conivaptan, grapefruit 
juice, indinavir, itraconazole, ketoconazole, lopinavir, nefazodone, nelfinavir, 
posaconazole, ritonavir, saquinavir, telaprevir, telithromycin, voriconazole) and 
CYP2D6 (bupropion, fluoxetine, paroxetine, quinidine) 
 
It is recommended that doses higher than 0.4mg daily should not be used in 
combination with strong inhibitors of CYP3A4 or CYP2D6 and that caution 
should be exercised when using tamsulosin in combination with such drugs.  
Studies have demonstrated an increased AUC and Cmax when tamsulosin is taken 
in combination with strong inhibitors of CYP2D6 or CYP3A4, but these increases 
have been shown to still fall equivalently or below the higher U.S. dosage of 
0.8mg daily.  One study specifically examining clinical effects (i.e. orthostasis) of 


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concomitant tamsulosin/paroxetine and tamsulosin/ketoconazole found no 
significant clinical effect of these medications being co-administered.  Patients 
taking strong inhibitors of CYP3A4 or CYP2D6 will not be excluded from the 
study, however they will be advised about potential increased risk of side 
effects. 
 
9.1.9 
Availability: commercially available 
 
9.1.10 Side effects (reported in package insert; data derived from two U.S. clinical trials 
(US92-03A and US93-01)7,8: 
 
 
Tamsulosin 0.4mg 
(n=502) 
Placebo 
(n=493) 
Body as whole 
Headache 
Infection 
Asthenia 
Back pain 
Chest pain 
 
97 (19.3%) 
45 (9.0%) 
39 (7.8%) 
35 (7.0%) 
20 (4.0%) 
 
99 (20.1%) 
37 (7.5%) 
27 (5.5%) 
27 (5.5%) 
18 (3.7%) 
Nervous System 
Dizziness 
Somnolence 
Insomnia 
Libido decreased 
 
75 (14.9%) 
15 (3.0%) 
12 (2.4%) 
5 (1.0%) 
 
50 (10.1%) 
8 (1.6%) 
3 (0.6%) 
6 (1.2%) 
Respiratory System 
Rhinitis 
Pharyngitis 
Cough increased 
Sinusitis 
 
66 (13.1%) 
29 (5.8%) 
17 (3.4%) 
11 (2.2%) 
 
41 (8.3%) 
23 (4.7%) 
12 (2.4%) 
8 (1.6%) 
Digestive System 
Diarrhea 
Nausea 
Tooth disorder 
 
31 (6.2%) 
13 (2.6%) 
6 (1.2%) 
 
22 (4.5%) 
16 (3.2%) 
7 (1.4%) 
Urogenital System 
Abnormal ejaculation 
 
42 (8.4%) 
 
1 (0.2%) 
Special Senses 
Blurred vision 
 
1 (0.2%) 
 
2 (0.4%) 
Table reproduced (with modification) from Flomax package insert. 
 
In the two U.S. clinical trials referenced above, symptomatic postural hypotension 
occurred in 0.2% of men treated with tamsulosin 0.4mg vs. no patients in the 
placebo groups.  Syncope occurred in 0.2% of men treated with tamsulosin 0.4mg 
vs. 0.6% in the placebo groups.  Multiple testing for orthostatic hypotension was 
also performed in these studies, and demonstrated a 16% rate of at least one 
positive orthostatic test result in the tamsulosin 0.4mg subjects, vs. 11% rate in the 
placebo group.7,8 
 


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No men in the tamsulosin 0.4mg group or placebo group discontinued treatment 
due to abnormal ejaculation. 
 
In a double-blind RCT comparing tamsulosin 0.2mg to placebo in 140 women over a 
4-week period, there were 2 patients out of 70 in the tamsulosin group who had 
dizziness and asthenia (2.9%) compared to no adverse effects reported in the 
placebo group.9 
 
9.1.10.1 
Incidence not known (Post-marketing experience) 
 
9.1.10.1.1 Allergic reactions including skin rash, pruritus, angioedema of tongue, 
lips and face, urticarial.  This has been reported in patients with severe 
sulfa allergy, and therefore severe sulfa allergy is one of the exclusion 
criteria for this study. 
9.1.10.1.2 skin desquamation 
9.1.10.1.3 Priapism (probably less than 1 in 50,000 patients) 
9.1.10.1.4 palpitations 
9.1.10.1.5 hypotension 
9.1.10.1.6 constipation 
9.1.10.1.7 vomiting 
9.1.10.1.8 Intraoperative Floppy Iris Syndrome (IFIS): This is a clinical syndrome of 
a flaccid billowing iris, iris prolapse, and pupil constriction that has been 
described during cataract surgery and has been associated with 
tamsulosin.  This syndrome increases the difficulty of performing 
cataract surgery and increases the rate of complications associated with 
cataract surgery.10  It has been found to occur even up to a year after 
discontinuation of tamsulosin, and possibly longer.11  However, one 
prospective study evaluating outcomes after surgery in which IFIS was 
present found that when surgeons were aware of prior or current 
tamsulosin use, they were able to employ compensatory techniques 
resulting in a low complication rate.11 
 
9.1.11 Nursing implications 
 
Nursing staff would administer the study medication when the patient is in the 
hospital.   
 
 
10.0 STATISTICAL CONSIDERATIONS 
 
10.1 Randomization and stratification 
 
 
Subjects will be stratified by gender, pelvic/non-pelvic surgery, and high vs low IPSS score 
(which “high” defined as >=8, and “low” <=7) prior to randomization.  Subjects will be 
randomized with a 50/50 chance of being allocated to active drug or placebo.  Randomization 
will be performed by the Pharmaceutical Research Center, and the code sheet for 
randomization will be kept by the PRC.  Unblinding of study team members will only occur for 


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interim data analysis, which will be performed between May 15 and May 30, 2016.  Only 
subjects for who complete data collection (including 30-day postoperative outcomes) has 
been obtained will be unblinded at that time.   
 
For purposes of stratification, “pelvic” operations include the following: surgery involving the 
rectum (colorectal anastomosis, ileo-rectal anastomosis, IPAA, proctopexy, proctocolectomy, 
proctectomy, LAR, and APR). 
 
10.2 Sample size  
 
In this study, we propose to compare a group of subjects given a placebo and a group given 
tamsulosin in order to prevent postoperative urinary retention.  The primary endpoint is need 
for at least a single intermittent catheterization, treated as a binary outcome.  Secondary 
endpoints include need for indwelling catheter replacement (binary), time until first void 
(continuous), number of intermittent catheterizations (numeric), post-void residual urine 
volumes (continuous), UTI rates (binary), and length of stay (continuous).  The sample size 
calculation is based on the primary endpoint.  We will employ a two-tailed, two sample test 
for equality of proportions (chi-squared or Fisher's exact) at a significance level of 0.05 
(equivalent to one-tailed alpha of 0.025) in order to compare urinary retention rates as 
measured by our primary outcome.  Based on pilot data and information from the literature, 
we anticipate that 30% of the placebo group will experience urinary retention, and that the 
tamsulosin group will see a 50% reduction to a 15% urinary retention rate.  In order to achieve 
at least 80% power for detecting a significant group difference, we will need 134 subjects 
included in each study arm, or a total of 268 subjects.  However, to provide for a 10% drop out 
rate, we would need to plan to enroll 147 subjects in each arm, yielding an enrollment goal of 
294 subjects.   
 
10.3 Error levels 
 
 
Two-sided type I error level is set at 0.05, and type II error level is 0.20.   
 
10.4 Differences to be detected for comparative studies 
 
Based on institutional urinary retention rates and information from the literature, we 
anticipate that 30% of the placebo group will experience urinary retention, and that the 
tamsulosin group will see a 50% reduction to a 15% urinary retention rate.  This is the pre-
specified difference in the primary outcome that the study is designed to detect at a two-
tailed significance level of 0.05 and power of 80%.  The secondary outcomes that will be 
compared include need for indwelling catheter replacement, time until first void, number of 
intermittent catheterizations, post-void residual urine volumes, UTI rates, and length of stay.  
These secondary outcomes can be thought of as more hypothesis-generating.  We 
acknowledge that we may not be powered to achieve statistical significance for our secondary 
outcome measures. 
 
10.5 Estimated accrual rate / study duration 
 


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The estimated sample size needed to achieve the pre-specified statistical significance and 
power is a total of 268 subjects (134 subjects in each arm).  Subjects that withdraw from the 
study prior to surgery will be replaced.  We estimate that there will be a 10% drop-out rate, 
and therefore the enrollment goal to account for drop-outs is estimated to be 294 subjects 
(147 in each arm) in order to achieve an actual sample size of 268 subjects.  We initially 
predicted that we would need to replace subjects that received epidural anesthesia, but the 
interim analysis showed no significant difference in response between epidural and non-
epidural patients. 
 
The estimated accrual rate is approximately 1-2 subjects per week.  In order to enroll a total of 
294 subjects, this would take approximately 147-294 weeks, or 2.8-5.7 years.  After 
enrollment of the final subject, data collection will continue for 30 days beyond that subject’s 
date of surgery.  Expected study duration is approximately 3-6 years from the time that 
enrollment begins. 
   
10.6 Stopping rules 
 
The trial will be stopped if at interim data analysis there is a highly significant difference 
(p<0.001) between the tamsulosin group and the placebo group in the primary outcome.  Data 
monitoring will be performed by the ICTR DMC every 6-12 months as needed.  The single 
planned interim data analysis will be performed between May 15 and May 30, 2016, by the PI 
(Evie Carchman), Greg Kennedy, Christina Papageorge, and Glen Leverson for the purposes of 
a Master’s thesis project.  If the rate of either priapism or syncope in the tamsulosin group 
exceeds that of the placebo group by an absolute value of 10%, then the study will be 
stopped. 
 
10.7 Primary endpoint for interim and final analysis 
 
The primary endpoint for interim and final analysis is need for any intermittent catheterization 
after initial IUC removal.  This outcome will be compared primarily with an intent-to-treat 
analysis.  However, we will also perform an as-treated analysis.  Compliance will be measured 
based on pill-counts.  A subject will be considered “compliant” if greater than or equal to 70% 
of the pills that were supposed to be taken were actually taken.   
 
10.8 Hypotheses 
 
10.8.1 Primary 
 
10.8.1.1 We hypothesize that subjects treated with tamsulosin will have a decreased 
need for intermittent catheterization after initial IUC removal compared to 
those treated with placebo. 
 
10.8.2 Secondary 
 
10.8.2.1 Subjects treated with tamsulosin will have a lower rate of IUC replacement 
compared to those treated with placebo. 
 


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10.8.2.2 Subjects treated with tamsulosin will have a higher incidence of abnormal 
ejaculation, dizziness, and orthostasis compared to those treated with 
placebo. 
 
10.8.2.3 Subjects treated with tamsulosin will have a shorter time until first 
spontaneous void compared to those treated with placebo.   
 
10.8.2.4 Subjects treated with tamsulosin will have a fewer number of total 
intermittent catheterizations required per subject compared to those treated 
with placebo.   
 
10.8.2.5 The tamsulosin group will have a smaller average post void residual urine 
volume after first spontaneous void compared to the placebo group. 
 
10.8.2.6 The tamsulosin group will have a smaller proportion of patients being 
discharged from the hospital with an IUC compared to the placebo group.  
 
10.8.2.7 The tamsulosin group will have a lower incidence of urinary tract infection 
diagnosed within 30 days of operation compared to the placebo group. 
 
10.8.2.8 Subjects treated with tamsulosin will have a shorter average hospital length of 
stay (in days) compared to those treated with placebo. 
 
10.8.2.9 Male gender, high preoperative IPSS score, older age, pelvic operations, larger 
volume of intraoperative fluids, and epidural anesthesia will be risk factors for 
POUR. 
 
10.8.2.10 Higher risk patient groups will be most likely to benefit from tamsulosin 
therapy for the prevention of POUR. 
 
10.9 Maximum number of subjects 
 
We have allowed for a 10% drop out in our enrollment goal calculation.  If, however, drop-out 
rate exceeds the allowed 10%, we will enroll additional subjects to maintain 80% power at a 
0.05 significance level.  As a contingency plan, the maximum number of subjects we will enroll 
will be based on a 30% drop out rate.  This would yield a maximum number of subjects in each 
arm of 174, or a total maximum enrollment of 348 subjects. 
 
10.10 Plan for analysis 
 
To analyze differences between the tamsulosin group and the placebo group with regards to 
the primary outcomes, we will employ a one-tailed, two sample test of proportions (Chi-
squared or Fisher’s exact) at a two-tailed significance level of 0.05 in order to compare urinary 
retention rates, as defined by need for at least a single intermittent catheterization.  This 
analysis will be performed primarily with an intent-to-treat analysis.  However, we will also 
perform an as-treated analysis.  Compliance for the as-treated analysis will be measured 
based on pill-counts and subject report.  A subject will be considered “compliant” if greater 


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than or equal to 70% of the pills that were supposed to be taken were actually taken, and 
crossover from placebo to active drug did not occur.  Additionally, this analysis will be 
performed both including and excluding the subjects who receive epidural anesthesia.     
 
The secondary outcomes will be analyzed using either Chi-squared or Fisher’s exact tests for 
binary outcome measures, and Student t-tests for continuous outcome variables.  
 
The retrospective study to identify risk factors for POUR will be a logistic regression  
using our primary outcome as the response variable and the various preoperative and  
operative variables as the predictor variables.  We plan to look at risk factors both in  
the placebo cohort alone and the overall sample of all patients.  We will quantify the  
risks of each variable with odds ratios.   
 
In order to identify groups of patients most likely to benefit from tamsulosin, we will perform 
chi-squared or Fisher’s exact tests on subgroups of patients to identify variables that are 
associated with POUR, and then create interaction variables between tamsulosin and the key 
factors identified in the initial analysis.  We will also employ binary logistic regression in this 
analysis to identify odds ratios for the interaction variables.   
 
The interim analysis will be a two-sided two sample test of proportions (Chi-squared or 
Fisher’s exact) at a two-tailed alpha of 0.001 comparing differences in the primary outcome 
between the tamsulosin and placebo groups.  Given the very small p value chosen for interim 
analysis there will be little to no inflation of the overall type I error for the study.   
 
11.0 RECORDS TO BE KEPT 
 
11.1 Personnel in charge of managing study data 
 
Study data will be primarily managed by the study coordinator and sub investigator.    
 
11.2 Confidentiality 
 
Subjects enrolled in the study will be sequentially assigned a unique 3-digit study identification 
number, which will be used to identify the subject throughout the course of the study.  The 
link between the subject’s identifiers (i.e. name, MRN, birthdate) and the subject ID will be 
available in the OnCore system. All data exported from the system will only contain the 
Subject ID number, and will not contain other subject identifiers. 
 
All paper forms containing patient information or data will be kept locked in the offices of the 
PI or study coordinator. 
 
The data collected during the course of the study will be stored in the OnCore system.  OnCore 
is an electronic data management system that will be used to capture, edit, manage, and 
export study data for analysis. 
 
Subject identifiable information is restricted at multiple levels.  The research team will manage 
study data through OnCore.  Access to the OnCore system is restricted to those that have 


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been granted access by the software administrators.  User access requires supervisor 
approval, completion of HIPAA and Human Subjects Protection training, and completion of 
role-based training in the OnCore system. In addition, users’ access is limited to protocols for 
which they have some responsibility of protocol, subject, or data management. Within those 
protocols, the ability to view and modify data is restricted based on their role in the conduct 
of the research project (e.g. regulatory staff do not have the privilege to view subject 
identifiable information). 
 
In addition, the technical components of this software are managed by the UW-Madison’s 
School of Medicine and Public Health Information Technology Office (for server maintenance, 
software upgrades, etc.), and security and software support is provided by ICTR administrative 
staff. SMPH IT and ICTR administrative staff are able to access subject information in order to 
help end users of the software program when questions arise.  
 
All communication between the clients and the OnCore application takes place via Hypertext 
Transfer Protocol over Secure Socket Layer or HTTPS. HTTPS provide the ability for normal 
web based communication over an encrypted Secure Socket Layer (SSL) connection. This 
ensures that data passing between the client and OnCore is protected from unauthorized 
attempts to access the data. 
 
Data that is exported from the OnCore system will be coded.  As is necessary for the 
completion of remote data analysis and travel to/from conferences where data may be 
presented, this coded data may be transferred to a limited number of password-protected 
and encrypted laptops belonging to study staff as necessary.  In this case, data would be 
stored on a password protected and encrypted USB drive in order to transfer data to the 
laptop.  Laptops and USB drives will only contain coded data, and will be used only as 
necessary as described above.  Only study staff will have access to such USB drives and 
laptops.  Laptops and USB drives will not contain the key to the code. 
 
 
11.3 Data collection methods 
 
Data not readily available in the EMR will be collected using Case Report Forms.  Data will be 
collected from subjects’ electronic medical records and subject self-report by a study team 
member.  Prospective data regarding bladder function will be collected by a study team 
member while the subject is inpatient.  Data regarding AEs and UPs will be collected using a 
form (Adverse Event Log) by a study team member via interview of the subject or abstraction 
from the EMR.  Data regarding treatment for UTI will be collected over the phone by a study 
team member 30-40 days after the date of surgery and via chart review.  Subjects will be 
identified on the data collection forms by their unique study ID number.  Data will be 
compiled into a single database in OnCore.   
 
11.4 Data management 
 
Online Collaborative Research Environment (OnCore) will serve as the Clinical Trial 
Management System for this study. ICTR OnCore is supported by the UW School of Medicine 
and Public Health Information Technology (SMPH-IT) staff and managed by the UW ICTR 
Clinical Research Infrastructure System (CRIS).  


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OnCore is a sophisticated, web-based data management system that: a) ensures secure, easy 
data entry at multiple sites; b) integrates multiple data sources; c) provides controlled, secure 
access to sensitive data using role-based access control; d) provides workflow automation; 
and e) allows export and reporting of data for Data and Safety Monitoring Boards and 
biostatisticians.  
 
This software provides protocol management functions (e.g. subject scheduling; screening, 
data organization), maintains updated forms, addresses budget development, billing, and 
fiscal management, generates summary reports, and provides essential links with other 
research administration and electronic medical records systems. ICTR OnCore eases the 
burden of the individual researcher and unifies protocol management within research 
programs and across research sites, enhancing protocol integrity and regulatory compliance 
efforts.  
 
The ICTR OnCore support team will work with the investigator and study team to ensure that 
relevant, applicable study data are collected and entered into electronic Case Report Forms 
(eCRFs) through a secure web-based system with restricted access. 
 
11.5 Duration of study records 
 
Paper study records and the study master list will be destroyed once all data is transcribed 
into the database, analyzed, and published, no sooner than 7 years after completion of the 
study.  The data in OnCore will remain indefinitely, until the study team requests the data be 
manually deleted.  A de-identified version of the database will be kept indefinitely for possible 
future studies. 
 
12.0 PATIENT CONSENT AND PEER JUDGMENT 
 
Current FDA, NCI, state, federal, and institutional regulations concerning informed consent will be 
followed.   
 
Waiver of informed consent will be used for screening review of eligibility for potential subjects.  If 
deemed eligible, the study will be discussed with a prospective subject, and if the subject is 
interested, the informed consent process will proceed, culminating with signed consent 
documentation.   
 
Potential subjects will be given written and verbal information about the study, and will be given 
time to ask any questions, prior to providing signed informed consent.  Due to constraints of the 
study related to the medication starting 7 days preoperatively, consent and enrollment must be 
completed at least 7 days prior to the scheduled surgery.  If after the initial clinic visit, the patient 
has another scheduled preoperative clinic visit prior to 7 days preoperatively, then the patient will 
be given the opportunity to take the consent form home if they so desire, and then signed 
informed consent will be obtained at the next clinic visit.  If that clinic visit is the patient's last 
clinic visit prior to the date of surgery, informed consent will be obtained at that time unless the 
patient needs additional time to consider participation.  If the patient needs additional time to 
consider participation in the study, he or she may bring written materials home and study 


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personnel will follow up via telephone call.  If the patient is interested in participating in the study, 
then a visit will be arranged with a study team member (prior to 7 days preoperatively) for the 
patient to sign the consent form and complete enrollment. 
 
The consent process will occur in a private clinic room or office. 
 
 
13.0 DATA AND SAFETY MONITORING 
 
An adverse event log will be maintained for all subjects enrolled in the study.  A member of the 
study team will directly inquire about adverse events (via interview of the subject) when the 
subject reports to the hospital on the day of surgery (after 7 days of taking the study medication).  
The adverse event log will be updated again based on AEs reported in the EMR from the time of 
surgery until 48 hours after completion of the intervention portion of the study, and finally a third 
time via telephone call 30-40 days after surgery.  Four study team members (Evie Carchman, Greg 
Kennedy, Christina Papageorge, and Glen Leverson) will meet between May 15 and May 30, 2016, 
to perform interim data analysis on primary endpoint data for the purposes of a Master’s research 
project.   
 
13.1 Data Monitoring Committee 
 
We plan to utilize the UW ICTR Data Monitoring Committee (DMC) to oversee the study.  The 
UW ICTR DMC is co-chaired by Dave DeMets and Norm Fost and is comprised of experienced 
members (core plus ad hoc) with expertise required to oversee this study.  The DMC members 
will review protocol-specific reports created by statisticians using data pulled from the ICTR 
OnCore clinical research management system.  These standard reports will include an 
overview of study objectives, a review of actual and projected accrual rates, an evaluation of 
patient demographics for balance of randomization, and a summary of the number and 
seriousness of adverse events.  An interim analysis of study results may be performed and 
source documents may be reviewed to allow the DMC to independently judge whether the 
overall integrity and conduct of the protocol remain acceptable based on data provided and 
reported by the Principal Investigator. The DMC will make recommendations to the Principal 
Investigator that could include actions of continuation, modification or termination. 
 
In providing oversight for the conduct of this study, the ICTR DMC will meet every 6 months 
during the 3-year study to review all adverse events.  The predefined stopping points for this 
study will include excess rates of syncope, or priapism requiring medical treatment.  The 
boundary for excess harm will be an incidence of syncope or priapism in the tamsulosin group 
that exceeds that of the placebo group by an absolute value of 5%, or an observed excess 
harm which in the judgment of the DMC, is excessive.  We will report all serious adverse 
events to the DMC and the IRB oversight committee, the Health Sciences IRB in accordance 
with their reporting guidelines.  
 
The individuals responsible for data and safety monitoring are independent of the 
researchers. 
 


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If a subject prematurely withdraws from the study, then a study team member will call the 
patient (or visit the patient in the hospital) to inquire about adverse events. 
 
Between May 15-30, 2016, unblinding will occur for subjects for which complete data 
collection (30 days from operation) has been achieved, and interim data analysis will then be 
performed by Evie Carchman (the PI), Greg Kennedy, Christina Papageorge, and Glen Leverson 
for purposes of a Master’s research project.    
 
13.2 Study Monitoring Service (SMS) 
 
While many institutions involved in clinical research conduct various types of quality 
assurance reviews and audits, UW ICTR is one of a few institutions to offer Study Monitor of 
Record services, a robust academic equivalent to the industry Contract Research Organization 
(CRO) standards for ongoing study monitoring.  
 
The SMS will offer three types of compliance review activities on this study: 1) Study Monitor 
of Record Reviews; 2) Routine (Random/QA) Reviews; and 3) Directed (For-Cause) Reviews. 
The Study Monitor of Record activities will be contracted for the proposed study, and will 
include the conduct and follow-up of monitoring visits throughout the life cycle of the study 
(e.g., Site Initiation Visit, Interim Monitoring Visits, and Close-Out Visit). Study monitoring 
visits will occur off-site (remotely) and/or on-site at a frequency necessitated by the protocol 
risk and complexity.  
 
For this study, UW ICTR SMS personnel will conduct a Site Initiation Visit (SIV) with the UW-
Madison research personnel in person after IRB approval is confirmed and before enrollment 
of any subjects into the study. The SIV will include a detailed review of the protocol, good 
clinical practice guidelines, and data management expectations of the research team at the 
study site and the SMS personnel. Following the Site Initiation Visit (SIV), SMS Monitoring 
personnel will routinely conduct ongoing Interim Monitoring Visits (IMVs) for all data 
collection sites, either on-site, remotely or a combination of both, following enrollment of the 
first subject(s) and throughout the duration of the study. During IMVs, the monitors will 
review study materials, including but not limited to: regulatory files, consent forms, case 
report forms, and device accountability logs. UW ICTR SMS personnel will conduct a Close-Out 
Visit (COV) upon completion of the study at the study site.  
 
Monitoring could consist of full or partial review of study records, depending on risk level and 
observed compliance. As such, during their monitoring activities, UW ICTR SMS personnel plan 
to review all (100%) of the study-related subject records for 10-20% of the enrolled subjects. 
The subject records of the first two subjects enrolled will be monitored in their entirety, with 
the additional number of enrolled subjects to be randomly. SMS personnel could increase the 
percentage of study or subject records to be reviewed if warranted by the ongoing monitoring 
findings.  
 
The study monitor(s) will work closely with the ICTR DMC statistician and the study statistician 
to conduct periodic central data reviews, with follow-up conducted by the study monitors for 
any data discrepancies identified. 
 


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14.0 REFERENCES 
 
1. 
Buckley BS, Lapitan MC. Drugs for treatment of urinary retention after surgery in adults. 
Cochrane Database Syst Rev. 2010(10):Cd008023. 
2. 
Choi S, Awad I. Maintaining micturition in the perioperative period: strategies to avoid urinary 
retention. Curr Opin Anaesthesiol. 2013;26(3):361-367. 
3. 
Lo E, Nicolle LE, Coffin SE, et al. Strategies to prevent catheter-associated urinary tract infections 
in acute care hospitals: 2014 update. Infect Control Hosp Epidemiol. 2014;35(5):464-479. 
4. 
Hollingsworth JM, Rogers MA, Krein SL, et al. Determining the noninfectious complications of 
indwelling urethral catheters: a systematic review and meta-analysis. Ann Intern Med. 
2013;159(6):401-410. 
5. 
O'Leary MP. Tamsulosin: current clinical experience. Urology. 2001;58(6 Suppl 1):42-48; 
discussion 48. 
6. 
Madani AH, Aval HB, Mokhtari G, et al. Effectiveness of tamsulosin in prevention of post-
operative urinary retention: a randomized double-blind placebo-controlled study. Int Braz J Urol. 
2014;40(1):30-36. 
7. 
Narayan P, Tewari A. A second phase III multicenter placebo controlled study of 2 dosages of 
modified release tamsulosin in patients with symptoms of benign prostatic hyperplasia. United 
States 93-01 Study Group. J Urol. 1998;160(5):1701-1706. 
8. 
Lepor H. Phase III multicenter placebo-controlled study of tamsulosin in benign prostatic 
hyperplasia. Tamsulosin Investigator Group. Urology. 1998;51(6):892-900. 
9. 
Pummangura N, Kochakarn W. Efficacy of tamsulosin in the treatment of lower urinary tract 
symptoms (LUTS) in women. Asian J Surg. 2007;30(2):131-137. 
10. 
Yaycioglu O, Altan-Yaycioglu R. Intraoperative floppy iris syndrome: facts for the urologist. 
Urology. 2010;76(2):272-276. 
11. 
Chang DF, Osher RH, Wang L, Koch DD. Prospective multicenter evaluation of cataract surgery in 
patients taking tamsulosin (Flomax). Ophthalmology. 2007;114(5):957-964. 
 
 
15.0 APPENDIX  
 
ELIGIBILITY CHECKLIST 
 
Any patient being seen in a general surgery clinic at UWHC or the UW Digestive Health Center for 
possible complex intra-abdominal surgery is a potential subject. 
 
Inclusion criteria: 
 
  >= 18 years of age 
 English-speaking 
 able to provide informed consent 
 scheduled to undergo elective complex intra-abdominal surgery with a planned stay of at least 1 
night in the hospital after surgery 
 “complex intra-abdominal surgery” includes one of the following operations via ANY 
transabdominal approach (i.e. open, laparoscopic, hand-assist laparoscopic, single-incision 
laparoscopic, robotic): 


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o Partial colectomy 
o Total abdominal colectomy 
o Proctocolectomy 
o Low anterior resection 
o Abdominoperineal resection 
o Restorative proctocolectomy/IPAA 
o Proctopexy (transabdominal) for prolapse 
o Intestinal stricturoplasty 
o Lysis of adhesions 
o End or diverting colostomy reversal 
o Ileostomy reversal 
o Closure of enterocutaneous, enteroenteric, or enterocolic fistula 
o Partial or complete gastrectomy 
o Small bowel resection 
o Small bowel diversion/ostomy 
o Large bowel diversion/ostomy 
o Pancreaticoduodenectomy 
o Pancreatectomy 
o Hepatectomy 
o Gastric bypass 
o Sleeve gastrectomy 
o Nissen/Dor/Toupet fundoplication 
o Transabdominal adrenalectomy 
o Splenectomy 
o Complex abdominal wall hernia repair (i.e. Rives-Stoppa type repair, large laparoscopic 
ventral hernia repair) 
o Exploratory laparotomy 
o Other comparable complex intra-abdominal operation 
 
 
Exclusion criteria: 
 
 allergy or contraindication to tamsulosin 
 serious sulfa allergy 
 current use of an alpha blocker (alfuzosin, doxazosin, prazosin, silodosin, terazosin, verapamil, 
tamsulosin, phenoxybenzamine) or oral alpha agonist (midodrine) 
 current warfarin use 
 current indwelling urinary catheter, suprapubic catheter, or urostomy 
 end stage renal disease or dialysis-dependent 
 sitting systolic blood pressure in the upper extremity of less than 100mmHg at time of eligibility 
screening 
 presence of orthostatic hypotension at the time of eligibility screening 
o orthostatic hypotension is defined as a drop in systolic blood pressure of 20mmHg from 
sitting to standing, or drop in diastolic BP of 10 mmHg from sitting to standing after 2-3 
minutes of standing after being in a sitting position 
 anticipated inability to take oral medications on post-operative day #0 
 anticipated requirement for indwelling urinary catheter beyond post-operative day #2 
 


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 non-English speaking 
 pregnant or breast-feeding women 
 lacking capacity to provide informed consent 
 unwillingness to answer all 7 questions on the IPSS survey 
 
 
 


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INSTITUTIONAL BLADDER MANAGEMENT PROTOCOL FOR ADULT SURGICAL INPATIENTS  
(Standard of care for post-operative general surgery patients) 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
No 
Straight 
catheterize 
No 
No 
No 
Yes 
END ALGORITHM: 
After 24 hours of 
straight catheterization, 
insert indwelling urinary 
catheter. 
Yes 
If no 2nd void 
in 6 hours 
Yes 
Bladder scan 
>500mL or patient 
reports bladder 
discomfort 
Bladder scan 
after 6 hours if 
no void 
Yes 
2nd post-
void residual 
<200mL? 
Yes 
END ALGORITHM 
START: 
• On arrival to unit from PACU without 
indwelling urinary catheter 
• Concern for urinary retention 
• Indwelling urinary catheter discontinued 
Bladder scan 
for PVR 
PVR <200mL? 
PVR <500mL? 
Has patient been 
consistently 
straight 
catheterized for 24 
hours? 
Patient 
voids 
Yes 
Bladder scan every 
2 hrs until >500mL 
or patient reports 
bladder discomfort 
No 
No