Micturition Flashcards
Micturition reflex
Afferent impulses from stretch receptors to pons
Pontine micturition centre activate
Parasymp. efferents stimulate detrusor muscle (S2,3,4), opening internal urethral sphincter
Sympathetic efferents inhibited
Pudendal nerve (S2,3,4) -somatic efferents inhibited –> external urethral sphincter relaxes
Normal bladder mode
Storage mode
Normal 70kg adult micturition
4 times in 24 hours
1.5L
Bladder contraction percentage in 24h
0.3%
Bladder contraction
ACh release from cholinergic nerves
Stimulation of muscarinic receptors on detrusor muscle
Diagnosis LUTS
History
Personal history
Past medical history
Physical exam
Micturition Obstruction disorders
BPH
Lithiasis
Strictures
Cancer
Micturition Incontinence disorders
Stress
Urge
Mixed urinary incontinence
Micturition functional disorders
Stroke
Spinal cord injury
Neurologic disease
Micturition medical disrders
Organ failure- renal, hepatic, cardiac
BPH
Hypertrophied detrusor muscle
Prostate larger + hypertrophied –> obstructs urinary flow
Caffeine
Releases calcium stores from Golgi apparatus in bladder wall
–> bladder contraction more likely
Alpha blockers
“stretchers”
Finasteride
Dutasteride
5 alpha reductase inhibitors
“shrinkers”
Tamsulosin
Doxazosin
Other drugs
PDE5 inhibitors
Antimuscarinics
TURP
Transurethral resection of prostate
Erection issues
HoLEP/Greenlight
Laser
Better at tissue removal
Less erection issues
UroLift
Newest technique
Mechanical
Preserves erections
Makes passageway for urine by holding prostate away from it
Anticholinergics
Oxybutyrin
Block ACh in PaNS nerves
Incontinence
Beta3- adrenergics
Incontinence
Mirabegron
Botulinum toxin A
Incontinence
Fuses synaptic vesicles with motor end plate
Neurogenic bladder
Lesions above pontine micturition centre are safe
Lesions bellow T12 are safe
Lesions in between are unsafe –> high pressure in bladder
