Urinary Elimination Flashcards
(79 cards)
Function of Kidneys:
major excretory organs
filter liquid waste from blood
balance salt and electrolytes in blood
regulate blood volume and pressure
produce erythropoietin for RBC formation
synthesize vitamin D
maintains acid-base balance of extracellular fluid
Urine is formed by:
tiny filtering units called nephron
Nephron:
functional units of the kidneys—-> consists of renal corpuscle and renal tubule
Renal Corpuscle:
compromised of a network of blood capillaries called glomerules
Renal Tubule:
compromised of the proximal tubule, loop of Henle, and the distal convoluted tubule
Filtration:
begins in the glomerulus as fluid moves across a membrane as the result of a pressure difference
Reabsorption:
occurs in renal tubule as most of the filtrate moves back into the blood; waste products are secreted
Secretion:
urine is produced
After exiting the kidneys, urine is carried to the bladder by:
ureters
The ureter wall muscles continually tighten and relax, forcing urine:
downward
Bladder walls relax and expand to:
store urine
Bladder walls contract and flatten to:
empty urine
Normal urine is:
sterile
Average adult passes:
960-1920mL/day
Urge:
innervation of the bladder signals when it is time to go
The brain signals the bladder muscles to tighten and the sphincter muscles to:
relax
when all the signals occur in correct order, urination occurs
Other names for urination:
voiding or micturition
Anuria:
failure of the kidneys to produce or excrete more than 50 - 100 mL of urine in 24 hours.
Ultrafiltrate:
liquid form which blood cells and blood proteins have been filtered out.
Oliguria:
defined as reduced urine volume. - less than 1mL in an infant - less than 0.5 ml in children - less than 400 mL in adults (symptom of acute/chronic renal failure)
Pre-renal failure:
result of reduction in blood flow to kidneys; causes dehydration, vascular collapse, and low cardiac output
Renal Failure:
seen in patients with actual kidney damage. (structural issues)
Post-renal failure:
related to mechanical or functional obstruction of urine flow
Polyuria:
excessive volume of urine found and excreted each day. Adult: 2500mL or more of urine per day