Renal System Study Guide
Renal System Study Guide
Med/Surg I
Major Functions of Kidney:
Regulation of Homeostasis
-Filters blood & regulates contents (water content & blood volume)
-Maintain acid-base balance
-Control fluid & electrolytes
-Excrete metabolic waste products
-Control BP (renin-angiotensin-aldosterone)
Urinary System Structure:
Kidneys (produce urine), Ureters (transport urine to bladder), Bladder (stores urine), Urethra (conduct urine outside body)
*Nephron- working unit of kidney
*Kidneys receive 25% of cardiac output= approx. 1 Liter
*GRF= 125ml/min & increases at night
Renal Hormones:
ADH- works in DISTAL CONVOLUTED TUBULE
Aldosterone- made in ADRENAL CORTEX
ANP- inhibits secretion of renin-angiotensin-aldosterone & water absorption by kidney tubules
Erythropoietin- stimulates marrow to make more RBC's
Renin- made & released in JUXTAGLOMERULAR APPARATUS
RENIN-ANGIOTENSIN-ALDOSTERONE
decreased renal perfusion= low BP
>JGA releases renin
>Liver releases angiotensin I
>Lungs convert angio I to angiotensin II
> Increase in BP due to VASOCONSTRICTION, myocardial contractility, - VOLUME INCREASE becase ALDOSTERONE is released by ADRENAL CORTEX >Aldosterone causes sodium & water to be REABSORPTION & potassium excretion
**** This stops once BP is normal because it is a NEGATIVE feedback system Lab Tests/Diagnostics:
Creatnine- 0.6-1.2 End product of muscle & protein metabolism -reflects GFR, renal disease is the only condition to increase creatnine level (not effected by hydration status)
BUN- 8-16 measures amount of urea (byproduct of protein metabolism in liver) -factors affecting BUN: hydration/ urine flow, hypoperfusion, metabolic rate, drugs, diet -Elevated BUN with normal creatnine= DEHYDRATION/Volume depletion/low perfusion -Elevated BUN & Creatnine= RENAL FAILURE/Dysfunction
Specific Gravity- 1.003-1.030 measures ability of kidneys to concentrate urine -increased spec. grav = (more concentrated urine)
Med/Surg I
Major Functions of Kidney:
Regulation of Homeostasis
-Filters blood & regulates contents (water content & blood volume)
-Maintain acid-base balance
-Control fluid & electrolytes
-Excrete metabolic waste products
-Control BP (renin-angiotensin-aldosterone)
Urinary System Structure:
Kidneys (produce urine), Ureters (transport urine to bladder), Bladder (stores urine), Urethra (conduct urine outside body)
*Nephron- working unit of kidney
*Kidneys receive 25% of cardiac output= approx. 1 Liter
*GRF= 125ml/min & increases at night
Renal Hormones:
ADH- works in DISTAL CONVOLUTED TUBULE
Aldosterone- made in ADRENAL CORTEX
ANP- inhibits secretion of renin-angiotensin-aldosterone & water absorption by kidney tubules
Erythropoietin- stimulates marrow to make more RBC's
Renin- made & released in JUXTAGLOMERULAR APPARATUS
RENIN-ANGIOTENSIN-ALDOSTERONE
decreased renal perfusion= low BP
>JGA releases renin
>Liver releases angiotensin I
>Lungs convert angio I to angiotensin II
> Increase in BP due to VASOCONSTRICTION, myocardial contractility, - VOLUME INCREASE becase ALDOSTERONE is released by ADRENAL CORTEX >Aldosterone causes sodium & water to be REABSORPTION & potassium excretion
**** This stops once BP is normal because it is a NEGATIVE feedback system Lab Tests/Diagnostics:
Creatnine- 0.6-1.2 End product of muscle & protein metabolism -reflects GFR, renal disease is the only condition to increase creatnine level (not effected by hydration status)
BUN- 8-16 measures amount of urea (byproduct of protein metabolism in liver) -factors affecting BUN: hydration/ urine flow, hypoperfusion, metabolic rate, drugs, diet -Elevated BUN with normal creatnine= DEHYDRATION/Volume depletion/low perfusion -Elevated BUN & Creatnine= RENAL FAILURE/Dysfunction
Specific Gravity- 1.003-1.030 measures ability of kidneys to concentrate urine -increased spec. grav = (more concentrated urine)