Neurological Control of Urinary Function Flashcards
What vertebrae are involved in the neurological control of the bladder?
L1 - L4 (Hypogastric nerve)
S1 - S3 (Pelvic and Pudendal nerve)
What are the roles of the urethra?
Outflow tract
Containment
What is the m of the bladder? What kind of muscle is it?
Detrusor muscle
Smooth muscle
What are the muscles and types of muscles of the urethra?
Internal urethra sphincter - Smooth
External urethra sphincter - Skeletal
What types of nervous innervation occurs during the storage phase in bladder control?
Sympathetic
Somatic
Outline the sympathetic innervation during the storage phase of bladder control….
Hypogastric nerve –> a and B adrenergic receptors –> detrusor muscle relaxes and urethral sphincter contracts
Outline the somatic innervation during the storage phase
Pudendal nerve –> nicotinic ACh receptors –> urethral sphincter contracts
What type of innervation is responsible for the voiding phase in bladder control?
Parasympathetic
Outline the parasympathetic innervation of the voiding phase in bladder control…
Pelvic muscle –> muscarinic ACh receptors –> bladder contracts
Where can the lesion occur in UMN bladder?
Pons –> L7 SC
What are the sings of UMN bladder?
Turgid, easily palpable bladder
Increased urinary sphincter tone
Difficult to express
Where can the lesion occur in LMN bladder?
Sacral SC or nerves
What are the signs of LMN bladder?
Flaccid, difficult to palpate bladder
Decreased urinary sphincter tone
Difficult to express
What are the problems associated with neurogenic bladder dysfunction?
Incontinence Urine scolding Urine stasis UTI Detrusor atony Pain/discomfort
Why can both UMN and LMN bladder result in incontinence?
UMN -> High intrabladder pressure so leaks
LMN -> Pressure from outside sources
How can the neurogenic bladder be managed physically?
Manual expression
Catheterisation
Cystostomy tube placement
What drugs can be used to help manage the neurogenic bladder?
- Retention Diazepam Bethanchol Phenoxybenzamine Prazosin
- Incontinence
Phenylpropanolamine
Outline the mechanism of diazepam in treating neurogenic bladder dysfunction…
Centrally acting muscle relaxant that decreases external urethral sphincter
Outline the mechanism of bethanechol in treating neurohenic bladder dysfunction…
Muscarinic cholinergic agonist that facilitates detrusor muscle contractility
Outline the mechanism of phenoxybenzamine and prazosin in treating neurogenic bladder dysfunction…
Alpha adrenergic antagonist that decreases internal urethral sphincter tone
Outline the mechanism of phenylpropanolamine in treating neurogenic bladder dysfunction…
Mixed alpha and beta agonist that increases internal urethral sphincter tone
