31. Disturbance of micturaton and defecation Flashcards
Innervation of the bladder
- Parasymp.: detrusor m. – pelvic n. (S2-S4)
- Symp.: hypogastric nerves (T12-L3)
- Somatic: pudendal n. (S2-S4)
- Sensory
Regulation of micturition
Needs autonomic and somatic nervous system.
Pontine mucturition center: full bladder –> detrustor contract. –> relax. ext. sphincter. Inh. by frontal lobe.
Pudendal n. (somatic) gives voluntary control over urethral sphincter
Disorders of micturition
- Spastic, neurogenic bladder
- Detrusor-sphincter dyssynergia
- Flaccid neurogenic bladder
- Frontal lobe incontinence
Spastic, neurogenic bladder
CNS lesion above sacral SC. Disinhibition and incr. sensibility (hyperreflexia) of detrusor muscle. Urge continence and decreased bladder capacity.
Detrusor-sphincter dyssynergia
Uncoordinated function of detrusor muscle and external sphincter. Urge to urinate, but ext. sphincter spasm leads to retention. From CNS lesions above sacral SC.
Flaccid neurogenic bladder
Hypotonic bladder wall – incr. capacity. Bladder wall is insensitive and paralyzed, leading to overfilling, overflow incontinence. Constant urine dripping. Lesion in sacral spinal micturition center or more distal (conus, cauda equina, peripheral nerves
Frontal lobe incontinence
Disorder affecting frontal lobes can cause detrusor hyperactivity and altered social behaviour regarding micturition
Regulation of defecation
- Pelvic plexus (S2-S4): defecation stimulus
- Parasymp.inferior mesenteric n.: incr. peristalsis and relax. ext. sphincter
- Symp.: decrease peristalsis
Disorders of defecation
Fecal retention
Fecal incontinence
Cause of fecal retention
Transverse lesion of SC above L1-L2 (where the hypogastric n. originate)
-Lack of fiber and water in your diet. - Side effect of medication (opiates, antipsychotics and calcium channel blockers)
Cause of fecal incontinence
Lesions of sacral segments
Causes of constipation (pelvic floor dyssynergia)
Diabetic neuropathy
Hirschprung disease
Parkinsons
MS
Spinal cord injury
