Renal VI: Sodium and Water Handling Pathophysiology

Question 1

_____ diabetes insipidus: results from collecting duct not appropriately responding to ADH

Answer 1

Nephrogenic

Question 2

_____ diabetes insipidus: results from deficiency of ADH and responds to administration of AVP

Answer 2

Central

Question 3

Causes of decreased total body sodium hypernatremia (3)

Answer 3

Diuretics, severe burns, GI losses

Question 4

Causes of edema (4)

Answer 4

CHF, nephrotic syndrome, cirrhosis, primary hormone excess

Question 5

Causes of euvolemic hyponatremia (4)

Answer 5

Primary polydipsia, adrenal insufficiency, hypothyroidism, SIADH

Question 6

Causes of hypernatremia (3)

Answer 6

Decreased, Normal, or Increased total body sodium categories

Question 7

Causes of hypertonic hyponatremia (2)

Answer 7

Mannitol administration, hyperglycemia

Question 8

Causes of hypervolemic hyponatremia (5)

Answer 8

CHF, hepatic cirrhosis, nephrotic syndrome, AKI, CKD

Question 9

Causes of hypotonic hyponatremia (3)

Answer 9

Hypovolemic, euvolemic, or hypervolemic categories

Question 10

Causes of hypovolemic hyponatremia (3)

Answer 10

GI losses, renal losses, diuretics

Question 11

Causes of increased total body sodium hypernatremia (1)

Answer 11

Hypertonic fluid intake

Question 12

Causes of isotonic hyponatremia (1)

Answer 12

Lab artifact

Question 13

Causes of normal total body sodium hypernatremia (1)

Answer 13

Diabetes insipidus

Question 14

High-pressure baroreceptors are located in the _______.

Answer 14

carotid body, aortic body

Question 15

In glomerulotubular balance, the fractional excretion of sodium is ______ with an increase in GFR

Answer 15

constant

Question 16

In hyperglycemia, an increase in serum glucose by 100 mg/dL results in a _____ in Na by ____

Answer 16

decrease; 1.6mEq/L

Question 17

In hypernatremia, the urine sodium is _____ if the cause is renal in origin.

Answer 17

> 20mEq/L

Question 18

In hypovolemic hyponatremia, the urine sodium is ____ if the cause is renal in origin.

Answer 18

> 20mEq/L

Question 19

In tubuloglomerular feedback, increased delivery of sodium to the _______ results in vaso_____ of the afferent arteriole

Answer 19

macula densa; constriction

Question 20

Intrarenal baroreceptors are located in the ______.

Answer 20

Juxtaglomerular Apparatus

Question 21

Low-pressure baroreceptors are located in the _______.

Answer 21

atria, LV, and pulmonary vascular bed

Question 22

Sosm =

Answer 22

2[Na] + BUN/2.8 + Glucose/18

Question 23

What is the site and mechanism of action for acetazolamide?

Answer 23

Proximal Tubule; Inhibits Na/H exchanger

Question 24

What is the site and mechanism of action for furosemide?

Answer 24

Loop of Henle; Inhibits Na/K/2Cl cotransporter

Question 25

What is the site and mechanism of action for spironolactone?

Answer 25

Collecting duct; competitive inhibitor of aldosterone

Question 26

What is the site and mechanism of action for thiazide diuretics?

Answer 26

Distal tubule; Inhibits Na/Cl cotransporter

Question 27

What is the site and mechanism of action for triamterene or amiloride?

Answer 27

Collecting duct; inhibit sodium channels

Question 28

When replacing fluids, the fluid infused should be _______.

Answer 28

Similar to the fluid lost