[10] Micturition Flashcards
Components: Bladder
Detrusor
Trigone
Ureterovesical Junction
Urethra
Bladder Neck
External Sphincter
Prostate
Nervous System Peripheral Nerves
Pudendal
Hypogastric
Pelvic
Phases of Micturition
Filling/Storage
Voiding
Define: Urodynamics
Study of hydrodynamics of urine storage and voiding
Urodynamic Measurement Recordings
Intravesical Pressure
Abdominal Pressure
Sphincter Activity
Urine Flow Rate
Normal Filling/Storage
No pressure
No leakage
No discomfort
Tracing of Bladder Pressure Is?
Flat (? Not too sure)
[Physiology of Normal Filling/Storage]
Detrusor
Compliant:
Control:
Compliant: Relaxes, accommodates
Control: No abnormal uncontrolled contractions
[Physiology of Normal Filling/Storage]
Urethra and Sphincter
Competent:
Control:
Competent: Closed, contracts
Control: Contracts as needed
[Physiology of Normal Filling/Storage]
Pelvic Floor
Contract:
Control:
Contract: To close
Control: Contracts more as needed
Define: Detrusor Compliance
Ability to maintain low pressure despite increase of volume during filling
[Anatomic Properties of Detrusor for Compliance]
Smooth Muscles
Viscoelastic property
[Anatomic Properties of Detrusor for Compliance]
Submucosa
Collagen and Elastin
[Anatomic Properties of Detrusor for Compliance]
Gap Junction Between Muscle Fibers
Slow Conduction
[Anatomic Properties of the Outlet for Closure: Competence]
Bladder Neck Factors
Intrinsic Factors
Abundant smooth muscle and elastic connective tissue to the passive closure of bladder neck during filling
[Anatomic Properties of the Outlet for Closure: Competence]
Bladder Neck Factors
Extrinsic Factors
Ligaments keep the neck of the bladder at an angle to the detrusor and provides support to the urethra
Urethral Smooth Muscle Layers and Roles
Inner Longitudinal Layer: Uncertain Role
Outer Circular Layer: Closure at rest, Urethral Resting Pressure
External Urethral Sphincter (Alternate Name)
Type of Fibers
Effect of Stress
Rhabdosphincter
Striated Slow Twitch Fibers exert a resting pressure during filling
During stress, cough valsalva, contraction causes rise in urethral pressure
Inner Urethral Factor (Alternate Name)
Spongy Tissue Within the Submucosa
Collagen and Elastic Fibers
Venous Plexus
What is a possible complication in women with regard to the Urethral Seal Effect?
It is hormonally regulated and postmenopausal women have thinner seals resulting in urinary leakage
What do you call the Pelvic Floor Muscle Group
Pubovisceralls
Muscles of the Pelvic Floor Muscle Group
Puborectalis
Pubovaginalis
Pubococcygeus
Pubourethralis
Pelvic Floor Connective Tissue
Endopelvic Fascia
Normal Voiding Characteristics
Adequate Pressure
Good Flow/Stream
No Discomfort
[Anatomy and Physiology of Normal Voiding]
Detrusor
Contractile
Control: Sustained stimulation to contract until empty
[Anatomy and Physiology of Normal Voiding]
Urethra and Sphincter
Calms Down: Relaxes and opens
Control: Inherent Contraction Inhibited
[Anatomy and Physiology of Normal Voiding]
Pelvic Floor
Calms Down: Relaxes and Opens
Control: Inherent Contraction Inhibited
[Detrusor Contraction]
Arrangement of smooth muscle fibers allowing sustained and complete emptying
Syncitium
[Detrusor Contraction]
Contraction of these muscles will close the distal ureter to prevent reflux of urine to the kidney
Trigonal Muscles
[Coordination of the LUT]
Filling and Voiding:
Detrusor/Bladder
Sphincter/Urethra
Pelvic Floor
Detrusor/Bladder -> F: Relax V: Contract
Sphincter/Urethra -> F: Contract V: Relax
Pelvic Floor -> F: Contract V: Relax
Micturition Switches
Cortical Center
Rostral Pons
Suprasacral Cord
Sacral Cord
Peripheral Nerves
a. Hypogastric
b. Pudendal
c. Pubic
[Inherent Actions]
Cortical Center
Inhibitory to Pons
[Inherent Actions]
Pontine Center
Stimulatory to sacral cord
Inhibitory to suprasacral cord
[Inherent Actions]
Suprasacral (T10-12) Hypogastric Nerve
Stimulates internal urethral sphincter
Inhibits detrusor
Inhibits trigonal muscles
