Bladder neurophysiology

  • View
    192

  • Download
    0

Embed Size (px)

Text of Bladder neurophysiology

Bladder & Bowel management

Bladder NeurophysiologyDr. Ali M AhmadMBBCh, MS, MD, MRCS-Ed, EBPSAssociate Consultant Pediatric Surgery; KAAUH_ PNU

Anatomy of Urinary Bladder

DetrusorFundusNeck internal sphincter Functional ,due to circular arrangementExternal sphincter Striated muscle under voluntary control

Trigone Located at base of bladder Extends from urethral orifices to bladder neck

Anatomy of Urinary Bladder

Storing the urine till convenient time to empty Function depends upon interaction among:Peripheral parasympatheticSympatheticSomatic innervations

Modulation from central nervous system

Neuroanatomy of the micturition

Storing the urine till convenient time to empty Function depends upon interaction among:Peripheral parasympatheticSympatheticSomatic innervations

Modulation from central nervous systemNeuroanatomy of the micturition

Originates from T10 L2Travel to lumbar sympathetic ganglion and from there to fundus and neck through hypogastric nerves

Provide excitatory input to bladder neck and inhibitory to fundus of bladder {relaxation of detrusor and contraction of internal sphincter hence enhancing storage of urine} Action through alpha & beta adrenergic receptors Sympathetic Efferent

Originates from detrusor nucleus in S2-4Travel through pelvic nerves to ganglion in fundus of detrusor

Provide excitatory input to fundus of bladder & contraction of detrusor Action through Action through cholinergic receptorsPara Sympathetic Efferent

Originates from pudendal nucleus in S 2-4Travel through pudendal nerve Provide excitatory /inhibitory output to pelvic floor & external sphincterSomatic Efferent

Sensation carried through hypogastric, pelvic & pudendal nerves to dorsal columns of Lumbosacral spinal cord

In the spinal cord sensation carried through lateral spinothalamic and dorsal columnsAfferents

PONTINE MICTURITION CENTERReceives input from cerebral cortex , cerebellum , basal ganglion & hypothalamusMost of the input is inhibitory but few are facilitatory.

Cerebellum important in Maintenance of tone in pelvic floorCo-ordination between bladder contraction and external sphincter relaxationCentral control

MICTURITION HAS TWO PHASES

Filling PhaseVoiding phase

Occurs when person not trying to void Sensations of fullness carried through the afferents and then through dorsal and spinothalamic tracts to pontine micturition center which is under the inhibitory influence of higher centers

Little rise in bladder pressure Maintained by progressive increase in sympathetic stimulation causing relaxation of body of bladder and stimulation of sphincters

S2-4 in cauda equina

pelvic & pudendal ns

PMCFilling Phase

At convenient time and place Withdrawal of inhibitory influence from PMC & + Excitatory input from other centers

Increase in parasympathetic deriveDecrease in sympathetic derive Contraction of bladder and relaxation of sphincters

S2-4 in cauda equina

pelvic & pudendal ns

PMCVoiding Phase