urinary system

Question 1

Struct. and func of urinary syst

Answer 1

Upper
2 kidneys –> form urine
2 ureters –> drain urine

Lower
Bladder –> stores urine
Urethra –> urine leaves body

Question 2

Main and side funcs of Urinary syst

Answer 2

Main: regulate ECF and excrete waste

Other: BP, EPO, vit D, acid base

Question 3

Kidney macrostructure

Answer 3

R lower than left
Retroperitoneal: T12 to L3
surrounded by fat and CT
Capsule of fibrous membrane
arteries, nerves, veins, ureters at hilus

Cortex = outer layer
Medulla = pyramids
Papillae = apices of pyramids
Calyces = funnel of urine to pelvis
Ureter = urine from pelvis to bladder

Question 4

Kidneys microstructure (UNNECESSARY)

Answer 4

nephron = func unit
-glomerulus
-bowman’s capsule
-tubular syst: proximal convoluted tubule, loop of Hele, collecting tubules

Cortex = glomerulus, Bowman’s capsule, proximal tubule

Medulla = loop of Henle and collecting tubules

Question 5

Kidneys and BLood supply

Answer 5

1200 mL/min (20-25% CO)

Aorta –> renal artery –> afferent arterioles –> glomerulus –> efferent arteriole –> peritubular capillaries –> renal vein –> inferior vena cava

Question 6

Steps of urine formation NOPE

Answer 6

filtration
reabsorption
secretion
excretion of H2O, electrolytes, and metabolic waste

Question 7

Glomerular filtrateion NOPE

Answer 7

blood filtered by hydrostatic pressure
passes thru semipermeable membrane into Bowman’s capsule
filtrate passes down tubule (shouldn’t have blood cells, platelets, or big prots)

Normal GFR is 125 mL/min

Question 8

Tubular func.NOPE

Answer 8

Reabsorption from tubules to capillaries

Secretion from capillaries to tubules
-proximal convoluted tubule (80% electrolytes, 100% glucose, AA and small prots, H+ and creatine)
-Loop of Henle: reabsorbs Na+, Cl-, and H2
-Descending limb: water sodium, urea, others
-ascending limb: Cl and Na

Question 9

Hormones on Distal convoluted tubule NOPE

Answer 9

ADH
-imp for water balance
regulated by post pit gland

Aldosterone
-reabsorption of Na+ and H2O; K+ secretion
-from adrenal cortex

Question 10

Acid base balance distal cocvoluted tubule

how does heart help with water balance? NOPE

Answer 10

Bicarb reabsorbed
H+ secreted

Right atrium
-ANP increases Na secretion; inhibits renin, ADH and Angio II; increases GFR

Question 11

Calcium balance in renal tubules NOPE

Answer 11

PTH increases calcium reabsorption and decreases phosphate reabsorption

vit D needed to absorb Ca from GI tract

Question 12

RBC production and BP regulation in kidneys

Answer 12

RBC- Erythropoietin is secreted in response to hypoxia and decreased renal bloodflow

BP :
-RAAS increases BP
-prostaglandin synthesis - vasodilation, decreased BP and SVR (systemic vascular resistance)

Question 13

Ureters: struct and func NOPE

Answer 13

carry urine from pelvis to bladder
-10 to 2” peristaltic, one-way flow

Joins renal pelvis at the ureteropelvic junction (UPI) and bladder at uretovesical junction (UVI)

Narrowed at junctions - obstruction –> renal colic

Reflux can occur with incomplete UI closure

Question 14

Bladder
what is normal urine output?
how much urine to stretch bladder?

structural features of bladder

Answer 14

Serves as reservoir for urine; doesn’t absorb; ureoepithelium stretches

Normal adult urine output: 1500 mL/day (0.5 cc/kg/hr)

200-250 = mil distention and urge to urinate
400600 = moderate distention (uncomfy)
600-1000 = capacity

trigone = 2 ureteral openings and bladder neck
bladder muscle = detrusor
Urachus = attachment to abdominal wall
urination, micturition, voiding

Question 15

Urethra

Answer 15

from bladder neck to external meatus
controls voiding
conduit for urine during voiding

Length:
M = 8-10 in
F = 1-2 in

Question 16

Urethrovesical unit NOPE

Answer 16

Formed by bladder, urethra, and pelvic floor muscles

Voluntary control = continence
-distention of bladder stimulates stretch receptors
-impulses sent from brain to T11-L2 and S2-S4
-Not time to void - inhibitor impulses stimulated
-Time to void - impulses from spinal cord causes relaxation and contraction of bladder neck, sphincter, and pelvc floor muscles

Question 17

Anatomic changes of old ppl’s urinary system

Answer 17

Bt ages 30-90 size and weight of kidneys decreases by 20-30%

By 7th decade, loss of 50% of functioning glomeruli

Atherosclerosis speeds decrease of size

continues to maintain fluid homeostasisi though

Question 18

Physiologic changes of old ppl’s kidneys, urethra, and bladder

Answer 18

Kidney
-less renal blood flow slows GFR
-altered hormones result in less concentrated urine and more excretion of water, Na, K and acid

Urethra and bladder:
F: less elasticity and muscle = infections and incontinence
M: enlarged prostate = dif urinary patterns

Question 19

Imp subjective data when assessing urinary syst

Answer 19

Health history: diseases or other probs
Meds: OTC shit, Nephrotoxic stuff
Surgery/treatments (including radiation or chemo)
Health perception
Nutritional/metabolic pattern
Elimination pattern (edema, pain, pattrn, color)
Activity level
sleep
cognition
self perception
role
sexuality

Question 20

Objective data when assessing urinary syst NOPE

Answer 20

Physical examination
-inspect skin, mouth, face, extremeties, abdomen, weight, general state of health
-palpate costovertebral angle (CVA), R kidney lower pole, and bladder (L kidney can’t be felt)
-percussion: kidney punch and bladder
-auscultation for bowel sounds

Question 21

Genetic risks NOPE

Answer 21

polycystic kidney disease and congenital uritary tract abnormalities

Question 22

normal physical asessment of urinary system NOPE

Answer 22

no costovertebral angle tenderness
nonpalpable kidney and bladder
no palpable masses

Question 23

Radiologic studies of urinary system

Answer 23

bowel prep
-magnesium citrate and fleet enema (except with kidney failure)
-iodine based contrast can cause contrast-induced kidney injury (CIN) and allergic reacions —> maintain hydration and administer N-acetylcysteine to deduce CIN)
-NPO - avoid dehydration; insulin adjustment for diabetics

Question 24

Urine studies

Answer 24

urinalysis = first morning void –> examine within an hour

Creatine clearance = best indicator of renal func
-collect 24 hr urine and blood specimen
-creatine clearance approximates GFR

Question 25

Urodynamic studies

Answer 25

1. Cystometrogram = catheter inserts saline into bladder to check capacity to contract and expel urine
2. RNC Radionuclide cystography = detects and grades vesicoureteral contractions –> VCUG-ish stuff with radioisotope instilled into bladder
3. sphincter electromyography (EMG) = Recording of electrical activity created when nervous system stimulates muscle tissue
4. Urine flow study = normal for men = 20-25 mL/s —> women = 25-30 mL/s
5. Videourodynamics
6. Voiding pressure study = combo of 1, 3, and 4
7. Whitaker study = measures pressure differential bt renal pelvis and bladder –> involves instilling fluid into renal pelvis

Question 26

Renal arteriogram with catheter insertion

urinary system cystoscopy