URO - Urinary incontinence Flashcards
Differentiate urinary incontinences and enuresis
Urinary incontinence: condition where involuntary loss of urine is a social/hygienic problem and is objectively demonstrable
Enuresis: any involuntary loss of urine
Nocturnal enuresis is normal in babies/ kids
Describe the physiological mechanisms for urinary continence
Anatomical support by
→ Intact pelvic floor holding bladder neck + urethra in place (esp in F)
Intrinsic urethral mechanism by
→ Coaptation of mucosa
→ Compression by submucosa and internal/external sphincters
Prostate as continence device in M → above factors less important
Neurological control by CNS and spinal cord
Somatic neural control of micturition
Anatomical structures involved in coordination and control
Parasympathetic, sympathetic and reflex control
- Pudendal nerve: from S2-S4 Onuf’s nucleus (anterior horn)
» Innervates striated sphincter, anterior levators, superficial perineal muscles
» Close external sphincter muscle in urethra - Pontine micturition center
Inputs (3):
» Corticol input from frontal lobes to inhibit micturition
» Afferent sensory input from stretch receptors in bladder Detrussor muscles
» Cerebellar input for coordinated voiding
Output (1):
» Sympathetic output from T10-L2 to Hypogastric nerve, merge with parasympathetic fibers to form pelvic plexus
» Contracts internal sphincter muscle in urethra - Sacral micturition center
» Communicates with pontine center for micturition reflex
Define normal void volume, residual volume
Define urinary frequency and nocturia
Normal void: 200-400mL
Normal residual: <150mL
Frequency: >8 voids during daytime, >Q2H
Nocturia: >2 voids during sleep, each void preceded and followed by sleep
Physiology of urine storage and voiding
Anatomical structures involved
High pressure or low pressure?
Urine storage:
- Bladder expands for low-pressure storage
- Bladder outlet closed at rest and even at high intra-abdominal pressure
- No involuntary bladder contraction
Urine voiding:
- Periodic voluntary urine expulsion at low pressure
- Coordinated contraction of bladder smooth muscles + relax sphincter muscles to remove anatomical obstruction at outlet
Anatomical abnormalities that lead to urinary incontinence?
Bladder:
- Detrussor overactivity (idiopathic, neurogenic)
- Low bladder compliance (SCI, cystitis, hysterectomy)
Sphincter abnormalities
- Extrinsic sphincter = Urethral HJypermobility due to weak pelvic floor muscle support
- Intrinsic sphincter deficiency (ISD) = abnormal urethral muscle, blood flow, innervation
Physiological pathway for micturition reflex and voluntary inhibition of micturition
Involuntary micturition/ micturition reflex:
- Intravesical pressure in bladder»_space; sensory input into pontine micturition center»_space; relaxation of sphincter muscles and THEN detrusor contraction»_space; induce involuntary emptying
Voluntary micturition: block somatic neural efferent activities
Stop micturition:
- Cortical input from frontal lobe into pontine micturition center»_space; inhibit micturition
Prevalence of urinary incontinence
Demographics
Most prevalent type
F»_space; M Mostly post-menopausal women
50-70 years old
Stress incontinence at 50%, Mix incontinence at 36%
5 major types of incontinence
Urge incontinence (UUI)
Stress incontinence (SUI)
Overflow incontinence
Functional incontinence
Mixed incontinence: urge + stress incontinence
Define Urge incontinence and underlying mechanism
Urge incontinence (UUI): strong desire to void that is difficult to defer and a/w leakage → Often mixed with SUI (mixed incontinence) and may be worsened by anxiety/stress → Mechanism: detrusor overactivity leading to inappropriate bladder contraction
Define stress incontinence and underlying mechanisms
Stress incontinence (SUI): leakage a/w Increase abdominal pressure → Mechanism: due to poor urethral sphincter function → Triggers: cough, sneeze, laughing, heavy lifting
Define overflow incontinence and underlying mechanism
Overflow incontinence: constant dribbling (esp at night) with associated retention of urine
→ Mechanism: BOO/DUA leads to abnormally distended bladder with large residual volume→ bladder over-distension with continuous dribbling
→ Signs: significant post-void residual, palpable bladder
→ Complications: UTI, bladder stones, obstructive uropathy
Define functional incontinence and underlying mechanism
Functional incontinence: urine leakage due to inability to get to toilet
→ Causes: impaired mobility (eg. elderly), dementia, lack of carer
→ Usually dx of exclusion as other types also present in functionally limited individuals
List general modifiable and unmodifiable risk factors of urinary incontinence (not specific to type)
Unmodifiable:
- White ethnicity
- Age > 50, post-menopausal
- Female sex
Modifiable:
- Smoking, Caffeine
- Obesity, Poor mobility
- Fluid intake level
Diseases/ Conditions associated with Urinary incontinence
Urogenital tract damage:
- Vaginal childbirth
- Anatomical disorders - VVF, ectopic ureter, urethral diverticulum
- Iatrogenic: pelvic, perineal and prostate surgery
- Radiation therapy
Neurological damage:
- CVA
- Parkinsons
- MS, SCI
UTI
DM
Medications
Ddx structural causes of urinary incontinence
Congenital duplex ureter
Infection
Iatrogenic - e.g. post-postatectomy sphincteric injury
Birth injury: vesico-vaginal fistula, stress incontinence
Neoplastic
Mechanisms of poor bladder compliance
- Increase viscoelasticity of bladder wall
- Filing rate exceeds rate of stress relaxation
- Over-filling beyond distensibility
Reversible, transient causes of urinary incontinence
D – delirium I – infection A – atrophic vaginitis or urethritis P – pharmaceuticals (see RHS) P – psychological disorders E – endocrine disorders R – restricted mobility S – stool impaction
Drug and food causes of urinary incontinence
Diuretics – urge Caffeine – urge Alcohol – urge Anticholinergics – overflow Alpha-agonists – overflow Beta-agonists – overflow Sedatives/antidepressants – overflow ACEI (cough) – stress
Ketamine cystitis
- Cause
- Physiological defect
- Presentation
Cause: Chronic ketamine abuse
Defect: Small, poor compliance bladder
Presentation: Urge incontinence, urinary frequency, obstructive uropathy
Urge incontinence
- Common causes
- Idiopathic overactive bladder (OAB)**
a) Neurogenic OAB:
- Brain: CVA, PD, Tumor, MS …etc
- Spine: injury, tumor, myelodysplasia …etc
b) Non-neurogenic OAB:
- Chronic BOO: BPH, urethral strictures, Pelvic mass
- Cystitis, bladder cancer
- Bladder stones
- Drugs: Diuretics, Caffeine, Alcohol
Stress incontinence
- Most common causes in male and female
Male:
- Prostate surgery**
- Spinal cord injury
- Drugs: a-blockers, ACEi
Female:
- Urethral hypermobility - poor pelvic floor support to urethra/ bladder neck, caused by birth trauma, increase IAP
- Intrinsic sphincteric deficiency: neuromuscular damage after pelvic surgeries
Overflow incontinence
Common causes in Male and female
Male:
1. Bladder outlet obstruction: BPH**, Spinal cord lesions
- Detrussor underactivity:
- Neuropathies and lower spinal cord disease
- Acute overdistension (e.g. post-op)
- Drugs: a-agonist, anticholinergics, antidepressants
Female:
- Detrussor underactivity: (more common)
- post-menopausal UG atrophy
- neuropathies and lower SC diseases
- Acute overdistension, eg. post-operative
- Drugs: α-agonists, anticholinergics, antidepressants - Bladder outlet obstruction
- External compression: fibroids, pelvic tumours
- Others: advanced POP, over-correction from prev OT
Patient presents with Incontinence a/w sense of urgency, triggered by running water, hand-washing, cold exposure
Most likely cause of incontinence?
Relevant history/ risk factors/ etiologies
Urge incontinence
Relevant history:
- Other LUTS, esp storage symptoms
- Hx of bladder pathologies, eg. UTI, stones, BPH
- Hx of neurological conditions, eg. stroke, SCI, and DM
- Drug Hx, eg. diuretics, and fluid intake incl caffeine/alcohol
Patient presents with Incontinence a/w physical exertion, coughing, laughing, lifting, rising from bed
Most likely type
Relevant history/ risk factors/ etiologies
Stress incontinence
- Chronic ↑abd pressure: chronic cough, obesity
- Obstetric history: multiparity, perineal tears
- Hx of prostate surgery: radical prostatectomy, TURP (usu not)
Patient presents with feeling of incomplete emptying, suprapubic discomfort, dribbling without any warning/ triggers
Most likely type of incontinence
Relevant history/ risk factors/ etiologies
Overflow incontinence
Relevant history:
- Other LUTS, esp voiding symptoms
- LL neurological symptoms and Hx of spinal cord diseases
- Hx of BPH or any other prostate pathology
- Gynaecological history, eg. fibroids, pelvic organ prolapse
- Drug history, eg. α-agonists, anticholinergics, antidepressants
Idiopathic overactive bladder
- Cause of which type of urinary incontinence
- Presentation
- Triggers
- Etiologies
Urge incontinence***
Presentation:
- Strong sense to void, then involuntary loss of urine
Triggers:
- worsened by anxiety/stress
- Etiologies:
Neurogenic OAB:
Brain: CVA, NPH, PD, brain tumour, TBI, MS
SC: injury, tumour, transverse myelitis, myelodysplasia
Non-neurogenic OAB due to bladder pathology
Chronic BOO: BPH, urethral stricture
Cystitis (infection/inflammation) and tumour
Bladder stones and bladder foreign body
Drugs: diuretics, caffeine, alcohol
Complications of overflow incontinence
- UTI
- Bladder stone formation
- Obstructive uropathy, worsen renal function
Patient presents with leaking of urine before reaching toilet, old-age
Most likely type of incontinence, causes
Functional incontinence: urine leakage due to inability to get to toilet
Causes: impaired mobility (eg. elderly), dementia, lack of carer
Outline history taking for urinary incontinence
Patient: Old age? Post-menopausal?
HPI:
Incontinence: Duration, type, frequency, volume/ number of pads, triggers and constant vs intermittent
Associated symptoms: Obstructive symptoms
Voiding/drinking habit: voiding diary if possible
PMH:
Neurological and mental health history
Gynaecological and Obstetic, Menstrual history
Urological history: UTI, surgeries …etc
Medication and social history: drug abuse, chronic drug use, caffeine/ smoking/ alcohol
Impact on quality of life
Outline list of P/E for urinary incontinence
- Post-void abdominal examination:
→ Palpable bladder indicates urinary retention - overflow incontinence
→ Abdominal mass compress on bladder - Pelvic examination in women → pelvic masses, organ prolapse, atrophic changes
- Rectal examination:
→ Feel for: anal tone (± faecal soiling), faecal impaction, rectal mass, BPH
→ Test reflexes: anal reflex, bulbocavernous reflex (BCR, S2-4) - Genital examination:
- Atrophy, cystocele, rectocele, skin excoriations, pelvic masses - Neurological examination if any suspicion of spinal cord/brain pathologies
First-line investigations for urinary incontinence
- Voiding diary: Frequency/ Volume charts
- Urinalysis, C/ST to r/o UTI
- RFT, Fasting glucose - obstructive uropathy, diabetic nephropathy
- Uroflowmetry - flow rate and post-void residual volume
- Urodynamic studies - Gold standard, for complicated incontinence:
Outline the recorded metrics and estimated metrics in Voiding Diary
Recorded: 24-72h
- Fluid intake, physical activity
- Frequency
- Void volume
- Incontinence episodes and triggers
Estimations:
- 24h urine volume
- Frequency
- Nocturia
- Functional bladder capacity
Urodynamic studies
- Indications
- Functions
Indication: Gold standard, for complicated incontinence
- Detrusor overactivity
- Voiding dysfunction
- Unclear clinical diagnosis
- Previous surgery for stress incontinence
- Any neurological deficits
Functions:
- Find etiology of incontinence
- Assess Detrusor function
- Assess pelvic floor prolapse
- Find urodynamic risk factors for urinary tract deterioration
List all metrics measured in Urodynamic studies
+ advantage of video UDS
- Flowmetry - Flow rate and residual urine
- Filling phase - Instability or hypotonia
- Voiding phase - Obstruction
- Video: shape of bladder, bladder neck, any reflux
- Better evaluation of bladder neck descent and urethra, clearly quantify anterior wall prolapse - Electromyography - striated sphincter function:
→ Leak point pressure (LPP): Pabd or Pdet required to overcome outlet resistance and produce incontinence
→ Urethral pressure profilometry (UPP): measures urethral pressure along its length
General lifestyle management for all types of urinary incontinence
Lifestyle modifications:
- Weight-reduction
- Less caffeine, alcohol intake, don’t reduce fluid intake
- Use incontinence pads
List non-pharmacological/ physiotherapy for urinary incontinence
Pelvic floor (Kegel) exercises
Biofeedback: placement of vaginal pressure sensor → live feedback of strength of pelvic floor contractions
Bladder training: timed voiding with controlling of urgency by distraction or mental relaxation techniques
List medical treatment options for urinary incontinence
Medical therapy: check for C/I to anticholinergics, usually require ~4w to see full benefit
- Anticholinergics, eg. oxybutynin, tolterodine, solifenacin
- Beta-3 agonist: Mirabegrone
- Vaginal oestrogen: suitable for postmenopausal women with vaginal atrophy
- Desmopressin: suitable for persistent nocturia
List surgical treatment options for urinary incontinence (excluding stress incontinence)
Surgical therapy:
- Sacral Nerve neuromodulation
- Posterior Tibial Nerve Stimulation (PTNS)
- botox injection
- augmentation cystoplasty
- urinary diversion
Surgical treatment options specific to stress incontinence
For stress incontinence only:
- Transurethral injection: bulking agents (eg. silicon, collagen)
- Mid-urethral sling (MUS): tension-free vaginal tape (TVT) in F, trans-obturator tape (TOT) in M
- Burch coloposuspension: suture lateral vaginal walls to iliopectineal ligaments
- Artificial urinary sphincter: most effective Tx for M, pump to deflate sphincter
Describe bladder training for urinary incontinence
Train Central control of voiding: timed voiding according to a schedule, stop voiding under urgency
controlling urgency by distraction or mental relaxation techniques
Antimuscarinic therapy for urinary incontinence
MoA
Effective time
MoA: Bladder contraction involves M3 receptors
Antimuscarinic drug acts as competitive antagonist against muscarinic receptros
> > Inhibits post-synaptic M3 receptors, stop Phospholipase3/IP3 pathway and Calcium influx
> > Reduce smooth muscle contaction
Time: 3-4 weeks before effect
List examples of antimuscarinic therapy for urinary incontinence and differences
Options if dry mouth cannot be tolerated?
Oxybutyninmost common: extended release, in transdermal or intravesical gel or rectal suppository, less systemic S/E
Tolterodine: less salivary gland S/E
Solifenacin: selective to M2, M3
Darifenacin: selective to M3
Quaternary: Less CNS S/E, e.g. Trospium chloride, Propantheline
Change to Tolterodine/ Transdermal, intravesical oxybutynin
S/E of antimuscarinic therapy
C/I
M1: Cognitive impairment
M2: Tachycardia, constipation
M3: Dry mouth, blurry vision, dizziness
C/I: Uncontrolled acute close angle glaucoma UC/ Toxic megacolon MG IO
Beta-3 agonists for urinary incontinence
Example
MoA
S/E
Mirabegron
MoA:
Activate adenyl-cyclase, ATP to cAMP > PKA > lower Ca influx > Smooth muscle relaxation
S/E:
Hypertension, Headache, UTI, Nasopharyngitis
Severe S/S:
CVD, CVA
Botox injection for urinary incontinence
MoA
Onset, repeat time
Botulinum toxin A injection - Intradetrusor injection
MoA:
Heavy chain binds to SV2 receptor
> endocytosis into presynaptic nerve terminal
> Light chain cleaves SNAP-25 protein on SNARE protein complex
> Stop exocytosis of Ach vesicles into NMJ
> Paralyze detrusor muscle
Block expression of TPRV1 and P2X3 receptors in Type C nerve
> decrease urgency
Onset: 1-2 weeks, repeat every 6-9 months
Botox injection for urinary incontinence
S/E
C/I
S/E: Urinary retention needing CISC UTI Haematuria Systemic absorption (rare)
C/I: Active UTI Bleeding diathesis MG Pregnancy/ breast feeding Allergy
Sacral neuromodulation for urinary incontinence
MoA
Complications
Temporary electrode inserted percutaneously»_space; into S3 sacral foramen with sacral nerve
Modulate local neural reflexes, inhibit bladder contraction
Stimulation shows big toe dorsiflexion, anal wink, cremasteric reflex
Complications:
- Surgery: Bleeding, infection, pain
- Implant: Mechanical failure, migration, Battery life (7y), Lower limb weakness
Augmentation cystoplasty for urinary incontinence
MoA
Complications
MoA:
Open bladder down to urethral orifice, patch defect with bowel segment (distal ileum)
Impair bladder contraction, lower detrusor pressure, increase bladder capacity, decrease strength of contraction
Complications:
Surgical: bleed, infection, leakage, ileus
Long term:
- CISC, mucus perforation, rupture
- Hypercholremic hypokalemic metabolic acidosis
- Malabsorption: fat, Vitamin B12, Bile acid»_space; Calcium oxalate stones, gallstones, anaemia
- Malignancy: Adenocarcinoma
Outline specific medical and surgical treatment options for Stress incontinence
General:
- Stop smoking, fluid management, lose weight
- Use incontinence pad
Medication:
- Duloxetine: SNRI → ↑5HT/NA activity in Onuf’s nucleus → ↑urethral sphincter activity
- Estrogen therapy
Surgical:
- Transurethral injection: bulking agents (eg. silicon, collagen) injected
- Mid-urethral sling (MUS): tension-free vaginal tape (TVT) in F, trans-obturator tape (TOT) in M
- Burch coloposuspension: suture lateral vaginal walls to iliopectineal ligaments
- Artificial urinary sphincter: most effective Tx for M, pump to deflate sphincter
Transvaginal tape for stress incontinence
MoA Complications (intra-op and post-op)
Reinforce functional pubourethral ligaments
Secure fixation of midurethra to pubic bone, reinforce suburethral vaginal hammock
Intra-op complications: - Bladder, urethral perforation - Hematoma, hemorrhage - Nerve damage Post-op complications: - Urinary retention - De novo urgency - UTI - Tape erosion
Gold standard treatment for male stress urinary incontinence
Artificial urinary sphincter: pump to deflate sphincter every time before voiding
