neuro9 Flashcards
(36 cards)
volitional control of micturition
dorsomedial frontal lobe connected to the medial region of the pontine micturition center; leads to decr in urethral pressure followed by incr contraction of the detrusor muscle
what does lateral region of the pontine micturition center do
contracts the urethral sphincter to promote storage of urine
what happens when PMC is damaged
when bladder becomes distented, the micturition reflex is activated at the spinal level; loss of inhibitory control
what is the spinobulbospinal circuit in bladder continence?
relfex arc that starts in the urinary bladder and projects to the pontine micturition center, with outflow connections to the parasymp sacral spinal motor nuc
what is the spinal segmental relfex arc in bladder continence
afferent fibers from the detrusor muscle to the Onuf’s nuc in the sacral spinal cord at S2-S4 and efferent fibers to the striated sphincter muscles through the pudendal nerve
spastic bladder
uninhibited detrusor contractions
atonic bladder
increased capacity, increased compliance; low voiding pressure and flow rate
detrusor-sphincter dyssynergia (DSD)
inapprop contraction of the external sphincter with detrusor contraction; can result in urinary retention, vesicoureteral reflux, and subsequent renal damage
overflow incontinence
LMN problem; lesions at the level of the conus medullaris, cauda equina, or sacral plexus; or peripheral nerve dysfunction
spastic bladder
UMN problem; lesions involving the frontal lobes, pons, or suprasacral spinal cord
voiding dysfunction in parkinsons patients
voiding dysfunction in 0-70% of patients; detrusor hyperreflexia is most common; pseudodyssynergia occurs as a conseq of sphincter bradykinesia
spinal shock and urinary dysfunction
during spinal shock, the bladder is acontractile, but gradually over weeks reflx detruso contractons develop in response to low filling volumes
spinal cord injury and urinary sx
spinal cord injury produces detrusor hyperreflexia, loss of compliance, and detrusor-sphincter dyssynergia
bladder dysfunction in MS
some common sx are irritative symptoms, obstructive symptoms, detrusor hyperreflexia, detrusor-sphincter dyssynergia
pudendal nerve
motor and sensory fibers to the penis and clitoris
parasymp nerves to the genitalia
S2 through S4, participate in erect
sympathetic nerves to the genitalia
T11 through T12 levels, through the hypogastric plexus; imp in ejaculation
chemicals released by parasymps that contrubute to sustained erection
nitric oxide and cGMP
pharmacologic therapy of erectile dysfunction
inhib of cGMP-specific phosphodiesterases
treatments for spastic bladder
anticholinergic agents, tricyclic antidepressants, desmopressin, intravesical capsaicin
treatments for stress incont
alpha adrenergic agonists, estrogen therapy, duloxetine
treatments for atonic bladder with overflow incont
Crede’s maneuver or valsalva to empty the bladder; intermittent self-catheterization; pharmacotherapy usually not effective
treatment for detrusor dyssynergia
intermittent catheterization, suprapubic catheterization, sacral nerve stimulaton, alpha-1 blockage (doxazosin)
tolteridine
anti-cholinergic
