Effect of Phenazopyridine on Prolapse Surgery Voiding Trials
Phase: PHASE3
Conditions: Urinary Retention Postoperative
Sponsor: University of Massachusetts, Worcester

Official title: Effect of Phenazopyridine on Prolapse Surgery Voiding Trials 
 
Study number: NCT03065075 
 
Date: February 1, 2017 
 
 

Study Protocol and Statistical Analysis Plan 
 
 
Study Protocol  
 
All subjects will receive 200 mg oral phenazopyridine before prolapse surgery, in 
the hospital’s pre-operative area. This is our standard of care in the post-indigo 
carmine era, for intraoperative ureteral patency verification. This study examines 
the effect of a second 200 mg dose. [Pharmacokinetic studies show that 90% of 
a 600 mg/day dose is excreted in the urine over 24 hours. There is minimal risk 
to receiving one additional dose, since 400 mg over 2 days is well below the 
recommended dose of 200 mg three times a day.]  
 
For the intervention group, the postoperative day 1 (POD1) 200 mg dose will be 
ordered to be given at 6am since void trials (VTs) occur later that day, as 
medically indicated by the subject’s recovery.  
 
The primary outcome will be determined by the proportion of subjects who fail a 
standardized VT prior to discharge. A successful VT is defined as a postvoid 
residual of less than half of the voided volume.  
 
Statistical Analysis Plan  
 
Comparisons between the intervention and control groups will be performed 
using Chi square, Fishers exact test (for cell counts <5), Students T-test, and 
Wilcoxon rank sum test. Intent-to-treat and as-treated analysis of VT results will 
also be performed. P-values <0.05 will be considered significant. All analyses will 
be performed using Stata MP 14.2 (StataCorp. 2015. Stata Statistical Software: 
Release 14. College Station, TX: StataCorp LP).