Bladder function and Dysfunction

Spinal shock almost always leads to what in urinary system?

spinal shock leads to areflexic non contractile bladder which can lead to overflow incontinence.

What is stress incontinence and what is it a sign of?

stress incontinence is unable to hold in urine when laghing/ sneezing etc.... Sign of urethral incontinence wein: failure to store due to outlet

Damage above S2 leads to what?

detrusor sphincter dyssynergia

What is the difference in contraction of the detrussor and the external sphincter?

detrusor: PNS: ACH on muscarinic External sphincter is somatic: ACH on nicotinic receptors

What are the 4 distinct Divisions of the male Urethra?

1. Bladder neck (prosthatic urethra) 2. Membranous urethra (external sphincter here) 3. Bulbar urethra (at penile base) 4. Pendulous urethra (shaft)

What 2 things make up the smooth sphincter?

1. Bladder neck and the 2. proximal urethra

Where is the secondary sphincter located in males? What is its function?

1. Bladder neck/ prostatic urethra Functions to help with continence and closes during ejaculation

What would excitation of the pelvic parasympathetic nerves cause?

1. It would cause excitation of the detrusor 2. relaxation of the proximl urethra

What are the 3 things that are necessary for Female continence?

1. Tone of female external sphincter 2. Firm support from anterior vaginal wall 3. Apposition of anterior and posterior walls of the urethral lumen

Describe how urine travels through the ureter.

1. Urine first leaves the distal tubules at the renal papilla through minor and major calyces and to renal pelvis then ureter. 2. Ureter has smooth muscle contractions peristaltic contractions like the hear to push urine through.

What 6 things can urodynamics detect? Should learn this.

1. bladder capacity/ compliance 2. bladder sensation 3. detrussor pressure at which storage and emptying occurs 4. if bladder is obstruced 5. if there is detrussor overactivity 6. presence of weak sphincter

WHata re the 3 types of urinary incontinence?

1. detrusor overactivity 2. urethral incompetence 3. overflow incontinence

What 3 things does the sympathetic hypogastric nerve stimulation cause?

1. inhibit detrusor contraction (Beta 3 adrenergic) 2. contracts the smooth muscle of the bladder neck and urethra (alpha 1 adrenergic) 3. inhibit Parasympathetic transmission

What 2 events can cause voiding?

1. relaxation of bladder outlet 2. contraction of detrusor muscle

What is the 3 ordered set of events in micturation?

1. relaxation of exernal striated sphincter 2. detrussor contraction 3. relaxation of smooth sphincter and urine flow

Why is smooth muscle supperior to skeletal muscle in bladder physiology?

1. smooth muscle shortens up to 2/3 its length (skeletal 1/3) 2. smooth muscle uses ATP slowly and effeciently

What are the 2 phases of micturation cycle?

1. storage 2. emptying

WHat 3 nerves innervate the lower urinary tract?

1.Pelvic Parasympathetic nerves 2.Lumbar sympathetic nerves 3. Pedundal nerves

Detrussor smooth muscle has what kind of afferent fibers?

A delta (large mylinated fibers)

What receptor on the bladder is responsible for detrussor contraction?

AcH stimulating M3 receptors cause detrussor contraction and bladder outlet relaxation

What would an Antimuscarinic drug treat in the bladder?

An antimuscarinic drug would treat an overactive bladder since activation of M3 leads to contraction of detrussor.

What is the other name for the external urethral spincter? Why is it called this? Why is this benefical?

It's called the rhabdospincter because the urethral smooth muscle in this area is surrounded by skeletal striated muscle. This is beneficial because it is slow-twitch type muscle which is resistnat to fatigue.

What receptors on the bladder body that cause detrussor to relax?

Beta 3 adrenergic receptors (stimulated by NE)

How is the bladder smooth muscle different than in other smooth muscles?

Bladder smooth muscle has outter circular muscularis layer and an inner longitudinal muscle layer

Where are C fibers located in the urinary system?

C fibers are found in the bladder mucosa

How do you evaluate for overflow incontinecne?

Check post void residual

What happens to the detursor and bladder outlet during voiding?

During voiding detrussor contracts and bladder outlet relaxes

Where is the primary zone of urinary continence?

External Urethral sphincter

What is the function of the smooth sphincter?

Helps with urinary continence, but not the main zone of urinary continence

Why is overflow incontinence an emergency?

It can lead to simultaneous bilateral hydronephrosis due to build up of urine.

What does AcH do to the detrussor muscle?

It causes contraction of the detrussor muscle

How is the bladder like a heart?

It has pacemaker Cells that cause random peristalsis.

What is the secondary urethra to bladder reflex?

This is when urine flow can lead to more urine flow by triggering involuntary bladder contractions

Lower thoracic damage will result in what?

Lumbar cord injury which means that it can't relax, thus has urinary frequency

Where is the rhabdosphincter in females?

Mid urethra

WHat would the excitation of the lumbar nerves to the bladder cause?

Nerves in the lumbar area going to the bladder would cause relaxation of the detrussor and constriction of bladderneck/proximal urethra (bladder outlet) It is sympathetic stimulation (NE post synaptic NT)

What 3 things happen when threshold is reached for voiding?

PMC sends efferent to both lumbar and sacral cord causing 1. inhibition of pudendal nerve: relaxation of external sphincter!!! 2. inhibition of hypogastric n: aborts guarding reflex 3. stimulation of parasympathetic excititory outflow.

What is the relationship of pressure in detrussor, intravesicle pressure, and intraabdominal pressure?

Pdet=Pves-Pabd

What nerves innervate the external sphincter in females? When can it be damaged?

Pedundal nerves can be damaged during child birth.

What is the term for inadequate emptying?

Post void residual (PVR)

Why is the renal calyces important in moving urine?

Renal calyces have the fastest pacemaker cells for smooth muscle of ureter

What is the voiding reflex called?

SPino-bulbo-spinal reflex: controlled by the brain stem, but can be suppressed with conscious control . The nuclei is located in the PONS called the pontine micturattion center

What is the wein classification?

States that storage or emptying caused by problems either in outlet, bladder, or both.

What is the guarding reflex?

Storage reflex: Afferent fibers caused by filling will synapse in the sacral and lumbar spinal cord This causes sympathetic outflow from hypogastric nerve leading to storage.

WHat is the relationship of tension, bladder radius, afferent nerves, and compliance?

T= Bladder pressure (radius/2) High radius= high tension tension can also increase with low compliant bladder. Afferent nerves sense bladder filling, thus when we have either big radius or low compliance, the afferent nerves will be more likely to send a signal to contract the detrusor.

What is the bladder base and what 2 things are in the bladder base?

The bladder base is where bladder and urethra connect 1. Trigone 2. Bladder neck

Where is the striated sphincter in males?

The striated sphincter is at the membranous urethra jsut distal to the apex of the prostate

What would excitation of the pedundal nerves cause?

These are under somatic cholinergic control, thus excitation causes the external sphincter to contract.

What is the periurethral muscle?

This is the muscle that is under conscious control and can affect the action of the external sphincter. It is both fast and slow twitch

What is hydronephrosis?

This is when the ureter pressure can't Overcome the pressure at the uterovesical junction, thus urine is backed up and the ureter becomes distended.

What is Urge incontinence and what is it s sign of?

Urge incontinence is needing to go suddenly with loss of suppression. SIgn of detrussor overactivity Wein: failure to store urine due to bladder

What is the place called in which ureter meets bladder?

Uterovesical junction (UVJ)

Where are alpha-adrenergic receptors found on the bladder? Activation of alpha adrenergics cause what?

alpha adrenergics are found on the bladder base and proximal urethra. Stimulation causes constriction of smooth muscle of bladder neck promoting urine storage

What is detrusor sphincter dyssynergia?

bladder contracts, but outlet fails to relax

What is the hallmark of overflow incontinence? Wein?

continuous leakage. Wein: failure to empty due to bladder and or outlet

What receptors are activated in contraction and relaxation?

contraction: AcH on M3 Relaxation NE on Beta 3 receptors causes increased cytosolic cAMP relaxing the detrussor muscles

SCI below S2 leads to what?

detrusor areflexia

Lesions above brain stem lead to what kind of bladder dysfunction?

detrusor overactivity: frequency, urgency, and urge incontinence