Micturition

Minimum urine production for a 30kg child is

15-30ml per hour

Approximately when do infants learn bladder control

2.5-3 years

State the healthy range of urine production

400-2,000ml urine daily normal fluid intake of 2L per day

Identify two divisions of the autonomic nervous system involved in bladder function

Autonomic nervous system- parasympathetic and sympathetic

Identify two muscular functions that are required for healthy bladder function

Detrusor muscle and sphincters

Outline the function of the detrusor muscle

Detrusor muscle remains relaxed to allow the bladder to store urine, contracts during urination to release urine

What type of muscle is found in the bladder

Detrusor muscle- the middle layer of the bladder wall, consisting of interlacing smooth muscle fibres and elastic tissue loosely arranged in three layers. When it contracts the bladder is emptied

Identify two neurological functions that are required for healthy bladder function

Intact nerve pathways. Pons micturition pathways controls nerve to bladder muscle- brain and spinal cord

Summarise the stages in healthy micturition

Intact nerve pathways: increased brain centres in frontal lobe Voluntary control of voiding Pons micturition pathways controls nerve to bladder muscle Normal muscle tone in detrusor muscles, sphincters and pelvic floor Absence of obstruction to urinary flow and any part of the urinary tract No inflammation of the body Capacity of 500ml Absence of enviro psychological factors Functional ability

What is urinary incontinence

Involuntary loss of urine which is objectively demonstrable and a social/ hygienic problem. Inability to control the voiding of urine

The organs of the urinary system

Kidney, bladder, ureters, urethra

The organs of the urinary system include

Kidney, detrusor muscle, ureter, urethra, urinary bladder

Identify two neurological problems that inhibit bladder function

Nerve damage/ trauma Brain disorders; stroke, tumour

Identify 4 substances that indicate pathology if detected in urine

Nitrate, protein,pH and glucose

Where in the spine is the micturition reflex co-ordinated

Sacral region of the spinal cord

Within the central nervous system the micturition reflex is co ordinated in the

Sacral spinal cord

External sphincter

Skeletal muscle and somatic nervous system

What type of muscle controls the external bladder sphincter

Skeletal muscle, voluntary control of somatic nervous system

The muscle in the urinary bladder is

Smooth and involuntary

Internal sphincter

Smooth muscle and autonomic nervous system

Which type of muscle controls the internal bladder sphincter

Smooth muscle, involuntary/autonomic control

Nervous system conditions that may inhibit bladder function

Spina bifida, stroke, multiple sclerosis, Parkinson's dosease

Regions of the central nervous system involved in the development of bladder control during infancy

Spinal cord, cerebellum, pons

State the neurotransmitter released by nerve endings in each system

Sympathetic-noradrenaline, parasympathetic/ somatic acetylcholine

What is the trigone

The three orifices in the bladder wall form a triangle or trigone. The upper two orifices on the posterior wall are the openings of the ureters; the lower orifice is the opening of the urethra. The internal urethral sphincter, a thickening of the urethral smooth muscle layer in the upper part of the urethra, controls outflow of urine from the bladder. This sphincter isn't under voluntary control

Name the tubes that run from the kidneys to the urinary bladder

Ureter

Name the tube that runs from the bladder to the exterior of the body

Urethra

Events which correspond to bladder emptying

Urethra relaxes, detrusor contracts, pelvic floor relaxes