Obturator Jerk in TURBT Clinical Trial
Official title:
Safety and Efficacy of Bipolar vs Monopolar Transurethral Resection of Bladder Tumor-A
Study design:
This was a single center, parallel arm, randomized, controlled trial done at Tribhuvan
University Teaching Hospital,Institute Of Medicine from May 2017 to April 2018. The
allocation ratio was 1:1.
Inclusion criteria: All patients undergoing Transurethral Resection of Bladder Tumor for
suspected bladder tumors.
Exclusion criteria were: Consent withdrawal, bladder tumour other than in the lateral wall,
unfit for spinal anesthesia and need of general anesthesia or obturator nerve block.
Methodology:
All patients suspected to have bladder cancer were subjected to imaging or cystoscopy and
with confirmation of the diagnosis; they were randomized into two arms of TURBT. Spinal
anesthesia was used in all cases. To overcome the potential confounding effect on our primary
end point, obturator jerk, nerve block was not used.
Cystoscopy was done first and the findings were noted before proceeding to TURBT.
Tumors were resected in block from periphery to center with the stalk resected last. An
additional sample of deep muscle was obtained from the tumor base and sent for
histopathological examination in different containers.
All study variables were recorded in Per forma during the operation and in post operative
period. Hemoglobin and sodium level was determined in immediate post operative period.
Postoperative irrigation was done with normal saline in both the resection groups and
continued till the urine was clear. The catheter was removed after 48 hours in uncomplicated
cases and patients were discharged. Patients were followed up in OPD at 2 weeks with the
All patients suspected to have bladder cancer were subjected to imaging or cystoscopy and
with confirmation of the diagnosis; they were randomized into two arms of TURBT. Spinal
anesthesia was used in all cases.
To overcome the potential confounding effect on our primary end point, obturator jerk, nerve
block was not used.
Cystoscopy was done first and the findings were noted before proceeding to TURBT.
Monopolar resection was done using 1.5% Glycine solution at 110 watt cutting, and 70 watt
coagulation power (Covidien Valley-lab Force Fx TM) with Karl Storz 26f resectoscope and loop
(8mm width and 5mm depth) with 300 telescope. Bipolar resection was done with 0.9% Normal
Saline with digital impedence dependent cutting (power range 150-250 watt) and 80 watt
coagulation power (Bowa Arc 400) with Karl Storz 26f resectoscope and loop (6mm width and 5mm
depth) with 300 telescope.
Tumors were resected in block from periphery to center with the stalk resected last. An
additional sample of deep muscle was obtained from the tumor base and sent for
histopathological examination in different containers. All study variables were recorded in
Per forma during the operation and in post operative period. Hemoglobin and sodium level was
determined in immediate post operative period.
Postoperative irrigation was done with normal saline in both the resection groups and
continued till the urine was clear. The catheter was removed after 48 hours in uncomplicated
cases and patients were discharged. Patients were followed up in Out Patient Department at 2
weeks with the histopathological report for or when necessary.
Study outcome:
The incidence of obturator jerk, bladder perforation, resection time, decrease in hemoglobin
and serum sodium, clot retention, need for blood transfusion, need for recoagulation and TUR
syndrome were recorded for the cases in both arms. All resected specimen were evaluated by
pathologist for quality by determining the presence of deep muscle in the sample and
comparing the degree of cautery artifact. Severe artifact was defined as more than 50%
cautery artifact in most chips.
Statistical Analysis:
Sample size (n) was calculated using 80% power and a 95% significance level for obturator
jerk, assuming a 30% incidence for the monopolar system and a 5% incidence for the bipolar
system. These values were arrived at after a comprehensive literature review. The sample size
was determined with the formula n= K {P1(1-P1) x P2(1-P2)}/ )P1-P2)2, Where:
N= sample size P1= prevalence of obturator jerk in Monopolar TURBT P2= prevalence of
obturator jerk in Bipolar TURBT K= constant (7.9 for 80% power of study and 0.05 level of
significance)
A sample size of 33 in each arm was calculated using above formula. Estimating a drop out of
10%, we decided to include at least 37 patients in each arm. A computer generated random
number was used to allocate eligible patients in to monopolar or bipolar resection arm. Data
analysis was done using Statistical Package for Social Sciences (SPSS) version 21.
Significance was determined using the independent sample t-test for quantitative variables
and the chi-square test for qualitative data. P value of <0.05 was considered statistically
significant.
;