Stress Urinary Incontinence (SUI)
Stress incontinence is leakage on effort — coughing, sneezing, lifting — because the bladder outlet can't stay closed against a sudden rise in abdominal pressure.
The big picture
Stress incontinence is leakage on effort — coughing, sneezing, lifting — because the bladder outlet can't stay closed against a sudden rise in abdominal pressure. It is a plumbing/support problem, mechanically opposite to OAB (a "bladder that squeezes too much"). The two mechanisms are urethral hypermobility and intrinsic sphincter deficiency (ISD), and management runs from pelvic-floor training to the midurethral sling — the modern surgical workhorse.
The framework: mechanism (hypermobility vs ISD) → diagnosis (demonstrate stress leakage) → conservative first → surgical options led by the midurethral sling.
Mechanism pathway
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Diagnostic algorithm
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Board traps
SUI = leak on effort (cough/sneeze/lift), no preceding urgency — a support/sphincter problem, opposite to OAB.
Two mechanisms: urethral hypermobility and intrinsic sphincter deficiency (ISD, ALPP <60 cm H₂O).
Cough stress test demonstrates it; urodynamics not needed for the straightforward index patient.
Pelvic-floor muscle training is first-line conservative.
Midurethral sling is the surgical workhorse; alternatives: autologous pubovaginal sling, Burch, bulking agents.
Counsel synthetic mesh risks as part of consent.
Duloxetine (an SNRI) raises striated sphincter tone via Onuf's nucleus for SUI — approved in Europe, not the US; for mild-moderate SUI and post-prostatectomy SUI.