1B urinary incontinence and BPH Flashcards
List the anatomical parts of the female GU system
- 2 kidneys
- 2 ureters
- Urinary bladder
- Urethra
Complete the following labels
What is the function of the kidneys?
- Remove waste products of metabolism
- Remove excess water and salts from blood
- Maintain the pH
What do the ureters do?
Convey urine from kidney to urinary bladder
What are the dimensions of the ureters?
- 25 cm in length- upper half lies in abdomen and lower half in pelvis
- 3mm in diameter but slightly constricted at 3 places
- Pelvic ureteric junction
- Pelvic brim
- As it passes through bladder wall
What three layers make up the ureter?
- Outer fibrous tissue
- Middle muscle layer
- Inner epithelium layer
What is the blood supply to the ureters?
- Dependent on where it is- renal/lumbar/gonadal/common iliac, internal iliac and superior vesical arteries
- Corresponding venous drainage
Lymphatics-wise where do the left and right ureter drain into?
- Left ureter → left para-aortic nodes
- Right ureter → right paracaval and interaortocaval lymph nodes
What is the nerve supply of the GU system?
Autonomic nervous system
What are some variations in kidney anatomy?
Single kidney (1% of the population)
Horse-shoe kidney
Ectopic kidney
What imaging is this?
CT (left) and IVU of horseshoe kidney
What are some variations in ureter anatomy?
Partial duplication
Complete duplication
Describe this imaging
IVU of bilateral partial duplication of ureters
What does ‘hold up’ points in the ureter mean?
Constriction points may block urine flow, especially if a kidney stone dislodges and becomes a ureteric stone (pain, ipsilateral impaired renal function)
Where are the hold up points in the ureter?
Where the renal pelvis joins the top of the ureter- pelvic ureteric junction (PUJ, or UPJ)
Pelvic brim, crossing the iliac vessels
As it passes through the bladder wall; uretero-vesical junction (UVJ, or VUJ)
What do these imagings show?
Idiopathic right PUJ obstruction (delayed nephrogram, swollen)
What does this imaging show?
Right VUJ obstruction (ureterocoele)
What is the purpose of the urinary bladder?
Muscular reservoir for urine
Describe the shape of the urinary bladder and where it resides anatomically
- When empty it’s a pelvic organ and when distended it rises into the abdominal cavity to become an abdomino-pelvic organ
- An empty bladder is a 4 sided pyramid and has 4 angles- apex, neck and 2 lateral angles
- It has 4 surfaces- the base, 2 inferiolateral surfaces and a superior surface
What three layers make up the urinary bladder?
- Outer loose connective tissue
- Middle smooth muscle and elastic fibres (detrusor)
- Inner layer lined with transitional epithelium
What is the blood supply of the female urinary bladder?
- Superior and inferior vesical branches of internal iliac artery
- Drained by vesical plexus which drains into internal iliac vein
Where does the urinary bladder drain into lymphatically?
Internal iliac nodes and then paraaortic nodes
What is the nerve supply of the urinary bladder?
Autonomic nervous system
Where does the female urethra run from and to?
from neck of bladder to exterior at external urethral orifice
Describe the difference between the internal urethral sphincter and external urethral sphincter
- Internal urethral sphincter- detrusor muscle thickened, smooth muscle, involuntary control
- External urethral sphincter- skeletal muscle, voluntary control
What is the blood supply of the female urethra?
Internal pudendal arteries and inferior vesical branches of the vaginal arteries with corresponding venous drainage
Where do the proximal and distal female urethra drain into lymphatically?
- Proximal urethra → internal iliac nodes
- Distal urethra → superficial inguinal lymph nodes
What’s the nerve supply of the female urethra?
Vesical plexus (proximal) and pudendal nerve (distal)
List the anatomical parts of the male GU system
- 2 kidneys
- 2 ureters
- Urinary bladder
- Prostate
- Urethra
Complete the following labels
What is the venous drainage for the male bladder?
Venous drainage by prostatic venous plexus which drains into internal iliac vein
Where is the prostate?
- Gland lying below the bladder in the male and surrounds the proximal part of the urethra
- Measures 4x3x2cm and conical in shape
- Connected to bladder by connective tissue
What are the three parts of the prostate?
- Left lateral lobe
- Middle lobe
- Right lateral lobe
What is the function of the prostate?
Secrete 75% of seminal fluid which liquifies coagulated semen after deposition in the female genital tract
What is the blood supply of the prostate?
- Inferior vesical artery
- Corresponding venous drainage
What do the lymphatics of the prostate drain into?
Internal and sacral nodes
What is the nerve supply of the prostate?
Autonomic nervous system
Where does the urethra go from and to in males?
- 20cm long
- Runs through neck of bladder, prostate, floor of pelvis and perineal membrane to the penis and external urethral orifice at the tip of the male penis
What is the blood supply to different parts of the male urethra?
- Prostatic part- inferior vesical artery
- Membranous part- bulbourethral artery
- Spongy urethra- internal pudendal artery
- Corresponding venous drainage
Describe the lymphatics of male urethra
Prostatic and membranous urethra drain to obturator and internal iliac nodes, spongy urethra drains to deep and superficial inguinal nodes
What is the nerve supply of the male urethra?
Prostatic plexus
What is normal micturition?
Intermittent voiding of urine stored in bladder
What are the 2 phases of the micturition cyce?
- Storage
- Voiding
Describe the storage phase of micturition
- Bladder relaxed, serving as reservoir.
- Outlet contracted, preventing leaks.
Describe the voiding phase of the micturition cycle
Bladder contracts and expels urine, urethral sphincter relaxes and urethra opens
- Bladder should empty fully (<50 ml “post void residual”).
- 6 pees daily, 20 secs each means 2 mins per day spent voiding.
How does micturition happen in infants?
It’s a local spinal reflex where bladder empties on reaching a critical pressure
How does micturition differ in infants to adults?
In adults, voiding can be initiated or inhibited by higher control centre of the external urethral sphincter keeping it closed until it is appropriate to urinate
Describe the innervation of micturition and its process up until bladder emptying
- Bladder has M3 (muscarinic type 3) receptors that work with parasympathetic fibres S2-4 which are stretched and stimulated as the bladder fills
- This results in contraction of the detrusor muscle for urination
- At the same time parasympathetic fibres inhibit the internal urethral sphincter causing relaxation and allows for bladder emptying
What happens when the bladder empties?
- The stretch fibres become inactivated
- The sympathetic nervous system (originating from T11-L2) is stimulated to activate the beta 3 receptors
- This causes relaxation of the detrusor muscle allowing the bladder to fill again
Define stress urinary incontinence
Complaint of involuntary leakage on effort or exertion, or on sneezing or coughing
What are incidence rates of stress urinary incontinence and who does it affect more?
- Can affect up to 40% of women
- More common in older women → 1/5 women over 40 have some degree of stress incontinence
What are the risk factors of stress urinary incontinence?
- Ageing
- Obesity (increases intraabdominal pressure)
- Smoking
- Pregnancy (puts pressure on pelvic floor)
- Route of delivery
Describe the pathology of stress urinary incontinence
Impaired bladder and urethral support and impaired urethral closure
Usually when you sneeze or cough no leaking occurs because external urethral sphincter is closed but in stress incontinence the sphincter isn’t closed so coughing/sneezing or anything else that raises intraabdominal pressure causes leak
What are the signs and symptoms of stress urinary incontinence?
Involuntary leakage from urethra with exertion/effort or sneezing or coughing
What investigations would we do for for stress urinary incontinence?
- History and exam as above, positive stress test (demonstrable loss of urine on exam)
- Descent of pelvic floor on vaginal examination
- Urodynamics (put pressure line in bladder and another in back passage which tells us intraabdominal pressure- when the patient with stress incontinence coughs you can see spike in intraabdominal pressure but no bladder contraction)
How do we manage stress urinary incontinence?
- Non surgical- physio with PFE (pelvic floor exercises)
- Surgical
What are the surgical options for stress urinary incontinence?
- Mid urethral sling
- Colposuspension
- Periurethral bulking agents
What is mid urethral sling?
Synthetic mesh that’s put under urethra to provide it support
What is colposuspension?
We put 2 stitches on either side of bladder abdominally to elevate it
Reduces how much the bladder moves when patient coughs/sneezes so limits fluid loss
What is periurethral bulking agents?
Injections that are injected around urethral sphincter to bulk it to obstruct it so if patient coughs or sneezes, they don’t leak
Describe the neural control of micturition in summary
- Prefrontal cortex permits the pontine micturition centre in the brainstem to change from storage mode to voiding.
- This activates the parasympathetic nucleus (bladder contraction), and inhibits Onuf’s nucleus (sphincter relaxation)
Describe the pelvic organ nerve supplies
What are the autonomic receptors controlling the nerve supplies?
- Bladder neck: α-adrenergic
- Detrusor:
- Cholinergic M3/ M2
- β-adrenergic β-3
- Erectile: nitrergic
Which drugs target α-adrenergic receptors in the bladder neck?
Alpha blocker, e.g. tamsulosin
Which drugs target Cholinergic M3/M2 receptors in the detrusor?
Antimuscarinic
e.g. axybutynin, solifenacin
Which drugs target β-adrenergic β-3 receptors in the detrusor?
Agonist e.g. mirabegran
What drug targets nitrergic receptors in erectile function?
PDE5 inhibitor
Define urinary incontinence according to the International Continence Society
Any involuntary loss of urine
Define overactive bladder (urge urinary incontinence)
Urinary urgency, usually with urinary frequency (as many times as is bothersome for that particular patient) and nocturia, +/- urgency urinary incontinence (leaking)
What is the incidence of overactive bladder?
Overall prevalence of 16.6% in men and women over 40
What are the risk factors of overactive bladder?
- Age
- Increased BMI
- Prolapse
- IBS
- Bladder irritants (caffeine, nicotine, alcohol, spicy and tomato based foods)
Describe the pathology of overactive bladder?
- Not well understood
- Caused by involuntary detrusor (bladder wall) muscle contractions
Name 3 causes for involuntary muscle contractions in the detrusor
- Could be idiopathic
- Could be neurogenic (loss of central nervous system inhibitory pathways)
- Could be bladder outlet obstruction at urethra- if urine can’t get out then bladder muscle keeps trying to squeeze to get the urine out which makes it irritable
What are the symptoms and signs of overactive bladder?
- Urgency
- Frequency
- Nocturia
- Urgency incontinence
- Impact on QOL- sleep disorders
- Anxiety and depression
How do we assess overactive bladder in males?
Enlarged prostate in males- can cause obstruction
How do we assess overactive bladder in females?
Prolapse in women- urethra sits in anterior vaginal wall and if that prolapses down it drags urethra with it to form obstruction
How do we investigate overactive bladder?
- Exclude infection with urine dip/MSU
- Voiding diaries
- Bladder scan: assess post void residual
- Urodynamics
What are voiding diaries?
- 3 day bladder diaries
- They document:
- volume of what they’re drinking and what time
- How often they go toilet and what volumes they’re voiding
- Whenever they have urgency or urge incontinent episodes
What is post void residual assessment for?
- Check the patient is emptying bladder properly- sometimes they say they feel like there’s a little bit left after they’ve gone to the toilet
- Do this by scanning bladder post voiding to see residual
How much should post void residual be normally in ml?
<100ml or 1/3 or less than voided volume
What is the risk if the patient has increased post void residual?
They develop UTI
When do we assess urodynamics?
- Objective assessment of bladder function
- Do this in patients who have overactive bladder where conservative measures/medication haven’t worked and you do urodynamics to plan further management
What is the management for urge urinary incontinence?
- Behavioural/lifestyle changes
- Bladder retraining
- Antimuscarinic drugs
- Beta-3 agonist
- Bladder injections with botox
- Neuromodulation
- Augmentation cystoplasty
What is the definition of BPH?
Non malignant growth or hyperplasia of prostate tissue, common cause of lower urinary tract symptoms in men. Outward enlargement can be felt with rectal exam.
What are the risk factors of BPH?
Hormonal effects of testosterone on prostate tissue
Describe the pathology of BPH
Hyperplasia of both lateral lobes and the median lobe, leading to compression of the urethra and therefore bladder outflow obstruction. See hyperplasia of the stroma (smooth muscle and fibrous tissue) and glands
What are the signs and symptoms of BPH?
hesitancy in starting urination
poor stream
dribbling post micturition
can present with acute retention
What is an abdominal and rectal examination needed for in BPH investigation?
To exclude other causes for:
Bladder cancer (haematuria)
Prostate cancer (raised prostate specific antigen (PSA))
Urinary tract infections/ Prostatitis
Urethral stricture
What are the complications of BPH?
progressive bladder distention, causing chronic painless retention and overflow incontinence. If undetected can lead to bilateral upper tract obstruction and renal impairment, with patient presenting with chronic renal disease
What investigations are done for BPH?
- Urine dipstick/culture, post void residual, bladder diary
- Urodynamics
- Cystoscopy if concerned about bladder cancer
What bloods are done for BPH?
PSA
What imaging is done for BPH?
US to assess upper renal tracts
What conservative management is given to BPH?
Lifestyle: WL, reduce caffeine and fluid intake in evening, avoid constipation
What medical management is given for BPH?
- α blocker- prostate stromal smooth muscle and bladder neck. Blocking the receptor relaxes muscle tone
- 5-α reductase inhibitor-prevents conversion of testosterone into di-hydro-testosterone (which promotes prostate growth) so slowly results in shrinkage
What surgery management is given for BPH?
transurethral resection of the prostate (TURP)-debulks occluding part to produce adequate channel for urine to flow. Can also be done with laser. This is not the same as radical prostatectomy for cancer
