urinary system

What are the main functions of the urinary system?

Regulates fluid volume, controls blood pressure, removes metabolic waste/drugs, activates vitamin D, maintains pH balance, and produces hormones.

At what bladder volume does the urge to urinate typically begin?

200–300 mL

What triggers the urge to urinate?

Stretch receptors sending signals to the brain

Is urination voluntary or involuntary?

Voluntary (in adults)

What happens during urination?

Bladder contracts and external sphincter relaxes

Why are females at higher risk for UTIs?

Shorter urethra

what is glomerular filtration rate

Measure of how fast blood is filtered in the kidneys

normal gfr volume?

~125 ml

normal urine output?

~1,500ml

minimum output w/ ~2,000ml intake?

~800ml

what wastes do kidneys remove?

ammonia, urea, uric acid

What does BUN measure? (blood urea nitrogen)

Protein metabolism waste → kidney & liver function

Why is creatinine a good indicator of kidney function?

Fully excreted by kidneys and not affected by liver

Cloudy, foul urine with WBCs indicates?

UTI

Dark yellow urine indicates?

dehydration

Acetone odor indicates?

Diabetic ketoacidosis

protein in urine indicates?

glomerular damage

glucose in urine indicates?

diabetes mellitus

ketones indicate?

fatty acid metabolism

crystals indicate?

possible kidney stones

What does erythropoietin do?

Stimulates RBC production

What does renin regulate?

Blood pressure (RAAS system)

What happens to kidney function with age?

Decreases (fewer nephrons, atrophy)

What can result from decreased kidney function?

Waste buildup, anemia, hypertension, osteoporosis

What changes occur in the bladder with aging?

Less elastic, decreased capacity, weaker muscles

What is nocturia?

Nighttime urination

enuresis

involuntary urination after age 4-5

primary enuresis

never achieved nighttime bladder control

secondary enuresis

previously achieved control but bed wetting begins (stress/illness)

stress incontinence

loss of urine caused by intra-abdominal pressure(stress) on the bladder

Stress incontinence cause

weak sphincter or pelvic floor muscles

Overactive bladder(urgency incontinence)

sudden intense urge to urinate often followed by involuntary urine loss

overflow incontinence

inability to fully empty bladder(urinary retention)

symptoms of overflow incontinence

dribbling/weak urine stream

What causes neurogenic bladder?

Nerve damage (brain/spinal cord injury)

Types of neurogenic bladder

Flaccid (can’t contract) & spastic (over-contracts)

Most common UTI pathogen?

E. coli (75–95%)

Types of UTIs by location

Urethritis, Cystitis, Pyelonephritis

Complications of untreated UTI?

Sepsis, kidney damage, CKD

Causes of obstruction?

Stones, tumors, structural issues

What is urinary stasis?

Urine staying too long → infection risk

what can urinary stasis lead to?

UTI’s & structural damage

What is nephrolithiasis?

Kidney stones

Most common type(kidney stones)?

calcium oxalate

What is BPH?

Enlarged prostate causing urinary obstruction

common symptoms of BPH?

weak stream, retention, nocturia, dribbling

effects of bph on urinary system?

enlarged prostate(obstructs urine flow), urinary stasis(UTI risk), bladder walls thicken

 A patient leaks urine when coughing. What type of incontinence is this?

Stress incontinence

What condition involves inability to fully empty the bladder with dribbling?

Overflow incontinence

What is the best indicator of kidney function?

GFR

 Which symptom is commonly seen with BPH?

difficulty starting urination

What is a major complication of untreated UTIs?

sepsis

What triggers the release of renin?

low blood pressure

what is renin released from

kidneys

Renin converts angiotensinogen into:

Angiotensin I

Angiotensinogen is produced by the:

Liver

ACE (angiotensin-converting enzyme) is primarily found in the:

lungs

 What is the most potent effect of angiotensin II?

vasoconstriction

Angiotensin II stimulates the release of

aldosteron

main action of aldosterone

retains sodium and water

what happens to potassium when aldosterone is released

excreted

Overall effect of RAAS activation

increased blood pressure

which horome increased water reabsorption

ADH

Which medication class blocks the conversion of angiotensin I to angiotensin II?

ACE Inhibitor

patient taking ACE inhibitor should be monitored for?

hyperkalemia

 Which of the following would activate the RAAS system?

low blood pressure

Blocking RAAS would lead to?

decreased blood pressure

 Which of the following best explains how RAAS increases blood pressure?

Vasoconstriction and water retention