Urodynamics

Question 1

What are the aims of cystometry?

Answer 1

• characterises detrusor and urethral function during the filling phase by assessing the pressure/volume relationship of the bladder
• determines relative SUI and detrusor overactivity or other factors e.g. neurological disorders

Question 2

What are the variables measured in cystometry?

Answer 2

• total bladder capacity
• intra abdominal pressure, intra-vesical pressure (from which detrusor pressure can be calculated)
• presence of involuntary detrusor contraction (provoked or unprovoked), urgency or leakage
• Patient’s sensation of first desire to void and strong desire to voidW

Question 3

What are the indications for Cystometry?

Answer 3

• failed conservative management
• previous failed surgery
• to determine relative contributions of SUI and DOA

Question 4

What is the procedure for cystometry?

Answer 4

• Bladder is emptied - PVR taken
• pressure catheters are placed in bladder (measure intravesicular pressure), and in rectum (measure intra-abdominal pressure)
• machine calibrated and checked
• saline instilled into bladder. IVP and IAP continually measured
• patient notes 1st desire to void and strong desire to void
• when strong desire to void is sustained then filling is stopped and volume measured

Question 5

List 6 tests used in urodynamics

Answer 5

uroflowmetry
cystometry
post void residual
provokation test
urethral pressure profile
leak point pressure

Question 6

what does the urethral pressure profile show you?

Answer 6

urethral funciton

Question 7

what does leak point pressure refer to?

Answer 7

IVP at which point the urethra gives way

Question 8

for what reasons would you have to perform urodynamic testing in a woman who has SUI?

Answer 8

if diagnosis is unclear
any symptoms of OAB present
if there have been previous surgeries for the problem
failure to respond to meds
if neurological comorbidities exist
clinical trial