Urogynaecology Flashcards
What is the perineum and perineal body?
- Perineum = area between vestibule + anus, formed of ischiorectal fascia
- Perineal body = where the muscles insert, central tendon, contains the anal triangle, urogenital triangle + superficial perineal muscles. Is the bit torn/cut in parturition
What are the pelvic floor muscles?
Puborectalis, pubococcygyeus, iliococcygeus and coccygeus
Coccygeus - innervated by anterior rami of S4-5
The other 3 make up levator ani -
Describe the different levels of support of the pelvic organs
Level I: uterosacral ligaments (to upper vagina + cervix), arcus tendineous fasciae pelvis, ileopectineal ligament
Level II: medially from white lines to support A+P vaginal walls
Level III: perineal body + pubourethral ligaments
Urethrocele and cystoceles
Urethra/bladder bulge into anterior wall of vagina - may see at intraoitus
- Urethroceles often due to damage to anterior level 3 support
- Cystoceles often due to damage to L2 supports
Rectocele
Herniation of the rectum through a fascial defect, often a/w a lax perineum
Enterocele
Small bowel prolapses through the PoD, usually there is also a uterine prolapse, or it happens post-hysterectomy (cos level I support is damaged)
Uterine prolapses
Caused by deficient level I support, usually there’s also vaginal prolapse
- 1st degree - cervix descends in the vagina (often due to retroverted uterus)
- 2nd degree - cervix reaches intraoitus
- 3rd degree (procidentia) - cervix + body of uterus + vagina protrude through intraoitus
What are the causes of pelvic prolapse?
- Congenitally weak supports
- Acquired (majority)
- High parity: laceration/overdistension/instrumental delivery that damage the pelvic floor
- Raised intra-abdominal pressure: chronic cough, constipation
- Hormonal changes: reduced oestrogen at menopause leads to atrophy and reduction in support
Clinical features of prolapse?
- General: feeling of fullness and ‘dragging down’ discomfort in the vagina, protrusions through intraoitus, sacral backache (relief on lying down), often worse at end of the day, sexual dysfunction, dyspareunia
- Urethrocele/cystocele: may cause incomplete bladder emptying leading to recurrent UTIs, SUI, bulge in anterior wall on straining (seen with Sim’s speculum)
- Rectocele: defecation issues, reducible mass bulging into vagina, vaginal ‘flatus’
- Enterocele: if large may get incarceration or obstruction
- Uterine prolapse: discomfort on sitting, ulceration/bleeding, ureter compression causing UTI/hydronephrosis
How may prolapses be prevented?
- Specific hysterectomy techniques
- Avoid prolonged 2nd stage of labour (pushing stage), avoid premature bearing down
- Pelvic floor exercises
How are prolapses managed?
*Conservative: pelvic floor exercises, pessaries (need some pelvic floor support to keep it in, e.g. ring pessaries plus topical oestrogen if post-menopause)
Outline the types of urinary incontinence
- True incontinence: continual loss of urine usually from a fistula but can be due to retention with overflow
- Stress UI: involuntary loss from brief increases in abdominal pressure without detrusor contraction, usually injury to continence mechanisms e.g. sphincter damage plus lack of oestrogen stimulation (as in menopause)
- Urge/overactive bladder UI: sudden detrusor contraction with uncontrolled loss of urine causing urgency, frequency, nocturna. May be idiopathic detrusor instability, obstructive uropathy, DM, neuro e.g. MS or damage in pelvic surgery
- Mixed UI: mix of SUI+UUI, involuntary leakage a/w sneezing coughing etc
- Overflow: obstruction so urine can’t go anywhere else but leak out e.g. detrusor fibrosis
Clinical features of urinary incontinence
- SUI: leak on exertion often a small volume, may find a prolapse of the urethra + anterior vaginal wall
- UUI: leakage often a/w triggers for bladder contractions like cough (so can mistake for SUI), larger volume lost
How may urinary incontinence be assessed?
- Exclude UTI
- Frequency-volume chart: SUI normal frequency + bladder capacity, UUI increased frequency
- Urodynamic studies
How is stress urinary incontinence managed?
1st conservative: lose weight, stop smoking, treat chronic cough, pelvic floor training for at least 3m (8 contractions 3 times per day)
2nd surgery: tension-free vaginal tape (commonest), laparoscopic colposuspension, peri-urethral injection of a bulking agent
3rd medical: duloxetine (SNRI). S/e of anxiety, constipation, diarrhoea, dizziness, dry mouth, flushes, myalgia, palpitations, skin reactions, weight changs
How is urge urinary incontinence managed?
1st conservative: moderate fluid intake, reduce caffeine + alcohol, bladder training (minimum 6w, gradually increase intervals between voiding)
2nd medical: anticholinergics e.g. oxybutynin (avoid in frail older women), tolteridone, solifenacin (act on M2 or M3 receptors); intravaginal oestrogens for atrophy, botulinum toxin A, neuromodulation e.g. sacral nerve stimulation; mirabegron (beta 3 agonist) if needing to avoid anti-cholinergic s/es
3rd surgical: detrusor myomectomy and augmentation cystoplasty
What supports the vagina?
Anterior - pubovesicalcervical fascia
Posterior - rectovaginal septum
Lower - puborectalis muscle
What supports the uterus?
Vaginal walls and uterosacral ligaments (the round + broad ligaments are weak)
What are the issues with pessaries for prolapse?
- They need to have some pelvic floor strength to keep it in
- S/e can include ulceration and bladder-vagina fistulae
- They need replacing every 4-6 months
What are the contraindications + s/es for use of anticholinergics in urinary incontinence?
CI: acute glaucoma, myasthenia gravid, bowel obstruction
S/e: CPCSCSCS, xerophthalmia, arrhythmias, confusion
Which tissues control micturition?
- Detrusor muscle in bladder wall
- Internal urethral sphincter - smooth muscle that in men prevents sperm going into the bladder but in women is virtually absent
- External urethral sphincter - voluntary skeletal muscle, used to hold urine in when bladder is full
Why do babies have no control over their voiding?
Micturition is a spinal reflex with descending modulation, babies haven’t developed the descending modulation so when bladder reaches a certain level it voids
Outline the voiding reflex
- Micturition centre stimulated by high frequency activity in the sensory neurone (full bladder)
- Parasympathetic fibres activated to contract the detrusor
- Inhibitory signals sent to the M centre when not near a toilet to hold off, then excitatory signals when able to use toilet
- M centre sends inhibitory signals to the L centre to inhibit the storage phase when voiding which relaxes the IUS + stops sympathetics
- Rhythmic contractions of detrusor expel urine
What nerves control micturition?
- Pelvic nerve: PNS, branch of sacral n S2-4. Causes detrusor contraction for voiding
- Sensory pelvic n: S2-4, stimulated when bladder stretched
- Pudendal nerve: S2-4, somatic branch of sacral, voluntary control of the EUS (contracts)
What is the effect of a LMN lesion on micturition?
Bladder disconnected from higher centres so low detrusor pressure is sensed so sphincters relaxed - don’t feel bladder filling - large residual urine, lack of sense of needing to void, overflow incontinence
S2-4 affected - reduced perineal sensation + lax anal tone
What is the effect of a UMN lesion on micturition?
Dilated ureters, thickened muscle, high pressure contractions, poor sphincter coordination, constantly in active mode (so urine moves up into ureters/kidneys)
What are the RF for urinary incontinence?
- Predisposing: FH, race, anatomical/neurological variants
- Promiting: menopause, drugs, UTI, increased IAP, age, co-morbidities, obesity
- O+G: pregnancy, childbirth, pelvic surgery, prolapse
What investigations are indicated in urinary incontinence?
- Bladder diaries minimum 3d
- Vaginal examination - pelvic organ prolapse + ability to initiate voluntary contraction of PF muscles
- Urine dip + culture
- Urodynamic studies
