Session 8 - Micturition and incontinence Flashcards Preview

Semester 3 - Urinary > Session 8 - Micturition and incontinence > Flashcards

Flashcards in Session 8 - Micturition and incontinence Deck (70):

Give the three main parts of the bladder

• Body
• Trigone
• Neck


Give the histological layers of the bladder wall

• Transitional epithelium
• Lamina propria
• Submucosa
• Detrusor muscle
• Adventiia


What is the body/fundus of the bladder?

• Temporary store of urine


What is the trigone?

• Ureteric orifices and internal urethral orifice are at the angles of a triangle


What is the neck of the bladder?

• Connects the bladder to the urethra


Outline the structure of the detrusor urinae muscle

• Made from a meshwork of muscle fibres in roughly 3 layers
○ Inner longitudinal
○ Middle circular
○ Outer longitundinal


Why does the bladder have three layers of muscle?

• Arrangement of muscle gives the bladder strength regardless of direction it is being stretched in


What is detrusor muscle supplied by?

• Autonomic nervous system, not under voluntary control

Spinal nerve supply is bilateral


What is the internal urethral sphincter?

• Continuation of the detrusor muscle and made of smooth muscle
• Physiological sphincter at the bladder neck


What is a physiological sphincter?

• A sphincter which is indistinguishable from surrounding tissue at autopsy


What is the primary muscle of continence?

• Internal Urethral Sphincter


What is the external urethral sphincter

• Anatomical sphincter
○ Localised circular muscle thickening to facilitate action


What is the external urethral sphincter derived from?

• Pelvic floor muscles


What type of muscle is the external sphincter?

• Skeletal muscle under somatic, voluntary control
• Contracts to constrict urethra and hold in urine


What are the two innervations of the detrusor?

• Parasympathetic
• Sympathetic


Outline the parasympathetic innervation of the detrusor

• Pelvic nerve (S2-S4)
• Ach - M3 receptors



Outline the sympathetic innervation of the detrusor?

• Hypogastric nerve (T10-L2)
• NA -> B3 receptors
• Relaxation


What is the innervation of the internal urethral sphincter?

• Sympathetic
• Hypogastric nerve (T10 - L2)
• NA -> a1 receptors
• Contraction
• Parasympathetic
• Pelvic nerve


What is the innervation of the external urethral sphincter?

• Somatic
• Pudendal nerve (S2-S4)
• Spinal motor outflow from Onof's nucelus of the ventral horn of the spinal cord
• Ach -> Nicotinic teceptor
• Contraction


What are the four main functions of the nervous system in relation to the bladder?

• Provide sensation of bladder filling and pain
• Allow the bladder to relax and accomodate to increasing volumes of urine
• To initiate and maintain voiding so bladder empties completely, with minimal residual volume
• To provide an integrated regulation of the smooth muscle
and skeletal muscle sphincters of the urethra


What prevents retrograde ejaculation in men?

• Prostatic urethra


Give the nerve roots which control urine storage

• L1 & L2


Give the nerve roots which control bladder voiding



What are the two phases of the bladder?

• Emptying
• Filling


What occurs in the filling phase?

• The bladder relaxes and accommodates increasing volumes of urine
• The urethral sphincters increase their tone to maintain continence


What volume of urine is usually required to cause the urge to urinate?

• >150ml


What is the overall capacity of the urinary bladder?

• 350 - 750ml


Outline the nervous pathway which is activated once bladder has a volume of >400ml and urge to urinate arises

• Brain micturition centres -> Spinal micturition centres -> parasympathetic neurones -> Pelvic nerve -> Contraction of detrusor muscle -> Rise in intravesicular pressure


What occurs once there is a rise in intravesicular pressure in the bladder?

• Cerebral context makes a concious, executive decision to urinate by reducing sympathetic stimulation to the external urethral sphincter


What causes feeling of pain/temperature in bladder as it reaches 400ml filling?

• Afferent nerves from the bladder wall start to signal the need to void by producing pain/temperature


Outline the nervous pathways which is activated in the filling phase

• Brain continence centres -> Spinal continence centres -> Sympathetic neurones -> Hypogastric nerve


What does an increase of sympathetic stimulation to the bladder cause in the filling phase

• Hypogastric nerve stimulates relaxation of detrusor and contraction of the internal urethral sphincter
• Cerebral cortex makes concious executive decision no to urinate by increasing somatic stimulation to the external urethral sphincter


What three things must occur for bladder not to empty?

• Relaxation of detrusor
• Contraction of internal urethral sphincter
• Contraction of external urethral sphincter


Give four types of urinary incontinence

• Stress Urinary Incontinence
• Urge Urinary incontinence
• Mixed Urinary Incontinence
• Overflow Incontinence


What is stress urinary incontinence?

• Involuntary leakage on effort or exertion, or on sneezing or coughing


What is urge urinary incontinence?

• Involuntary leakage, accompanied by or immediately proceeded by urgencu


What is mixed urinary incontinence?

• Involuntary leakage associated with urgency and exertion, effort, sneezing or coughing


What is overflow incontinence?

• Retention of urine causing the bladder to swell. Can be low pressure and pain free


Which type of urinary incontinence has the highest incidence?

• Stress urinary incontinence


Give three categories of risk factors for urinary incontinence

• Obs and Gyny
• Promoting
• Presdisposing


Give three obs and gyny risk factors for urinary incontinence

• Pregnancy and childbirth
• Pelvic surgery
• Pelvic prolapse


Give three predisposing risk factors for urinary incontinence

• Race
• Family predisposition
• Anatomical abnormality


Give three promoting risk factors for urinary incontinency

• Cognitive impairment



What is an important physiological factor in maintaining continence?

• Support of the urethra by the muscles and ligaments of the pelvic floor are important for the efficiency of the sphincter mechanisms of the urethra that enables continence


Outline history taking from a patient with a history of Urinary incontinence

• Ask to record the amount of fluid they pass for two or three days
• Work out the number of pads that the patient has to use per day to cope with urine leakage
• Assess whether leakage continous or intermittent
• What precipitating factors are present (coughing/sneezing)


What can make urgency and frequency of micturition worse?

• Intravesicular inflammatory conditions due to UTI, stone in the bladder or tumour


How can past medical history assist in the assesment of UTI's?

• Previous surgery of the pelvic floor
• Childbirth can cause sphincter damage


Outline what information must be gathered in a urinary examination

• Height/Weight
• Abdominal exam to exclude palpable bladder
• Digital rectal examination (DRE)
○ Prostate
○ Limited neurological examination
• (Females) External genitalia

(Female) Vaginal exam


What investigations should be done in the case of urinary incontinence?

• Mandatory
○ Urine dipstick
• Basic non-invasive urodynamics
○ Frequency volume chart
○ Bladder diary
○ Post micturition residual volume
• Optional
○ Invasive urodynamics
○ Pad tests
○ Cystoscopy


What does management of urinary incontinence depend on?

• Symptoms patients have
• Degree of inconvenience they suffer as a result
• Previous or current treatments

Effects of treatments on other symptoms they may have


Outline conservative management of urinary incontinence

• Modify fluid intake
• Weight loss
• Stop smoking
• Decrease caffeine intake (UUI)
• Avoid constipation
• Timed voiding – fixed schedule


What treatment can be give to patients who fail conservative management but are unsuitable for surgery?

• Indwelling catheter
○ Urethral or suprapubic
• Sheath device
○ Analagous to an adhesive condom attached to a catheter tubing and bag
• Incontinence pads


Give specific management of Stress Urinary Incontinence

• Pelvic floor muscle training
• 8 contractions, 3x a day
• At least 3 months duration
• Void bladder, stop stream ß use those muscles in pelvic floor training


Give specific management of a urge urinary incontinence?

• Bladder training
• Schedule of voiding
○ Void every hour during the day
○ Must not void in between – wait or leak
○ Intervals increased by 15-30 minutes a week until interval of 2-3 hours
• At least 6 weeks of training needed


Give three pharmacological managements of patients with urinary incontinence

• Duloxetine
• Anticholinergics

Botulinim toxin


What is duloxetine?

• A combined noradrenaline and serotonin uptake inhibitor
• Increases the activity od the external urethral sphincter during the filling phase
• Offered as alternative to surgery


What is an anticholinergic?

• Act on muscarininc receptors, including the M3 receptors that cause the detrusor muscle to contract.


What is a downside of using an anti-cholinergic to treat urinary incontinence?

Many side effects due to effect on muscarinic receptors


Why is botulinim toxin sometimes used?

• A potent buiological neurtoxin that inhibits Ach release. Prevents detrusor muscle contraction as pelvi nerve cannot release Ach to act on the M3 receptors


What are the two main types of surgery in females for urinary incontinence?

• permanent intention
• Temporary intention


Give three types of permanent intention surgery in females

• Low tension vaginal tape
• Open retropubic suspension procedures
• Classic fascial sling procedure


What is low tension vaginal tape?

• Common, minimally invasive surgery
• Success rate of >90%
• Supports mid urethra with a polyprophylene mesh


What is open retropubic suspension procedure?

• Corrects the anatomical position of the proximal urethra and improves urethral support


What is the classic fascial sling procedure?

• Supports urethra and increases bladder outflow resistance
• Involves autologus transplantation of the fascia late or rectus fascia


Give a temporary female treatment for urinary incontinence?

• Intramural bulking agents improve the ability of the urthera to resist abdominal pressur eby improving urethral coaptation. This is achieved by injetions of autologous fat, silicone, collagen or hylauron-dextran polymers


Give two surgical treatments in men for UI

• Artificial urinary sphincter
• Male sling procedure


Outline the insertion of an artificial urinary sphincter in amales

• Treatment for urethral sphincter deficiency

Cuff is a mechanical device that stimulates the action of a normal sphincter to cicrumferntially close the urethra


Give three problems involved in the insertion of an artificial urinary sphincter

• Infection
• Eorsion

Device failure


What is a male sling procedure?

• Corrects stress urinary incontinence in males

Bone anchored tape attached to urethra


What is a male sling used to treat?

Stress urinary incontinence as a result of radical prostatectomy, colorectal surgery, radical pelvic radiotherapy