SM_199a: IVF and Diuretics

Question 1

Describe the normal values of electrolytes

Answer 1

Normal values of electrolytes

Na⁺: 140

K⁺: 4

Cl^-: 102

HCO₃^-: 24

BUN: 10-20

Cr: 1.0

Glucose: 60-100

Question 2

____ of total body water is intracellular, while is ____ of total body water is extracellular

Answer 2

2/3 of total body water is intracellular, while is 1/3 of total body water is extracellular

Question 3

Of the extracellular water, ___ is intravascular (plasma), while ___ is extravascular

Answer 3

Of the extracellular water, 1/4 is intravascular (plasma), while 3/4 is extravascular

Question 4

___ of extracellular water is plasma (intravascular)

Answer 4

1/4 of extracellular water is plasma (intravascular)

Question 5

____ is the compartment we measure when we sample blood

Answer 5

Plasma is the compartment we measure when we sample blood

Question 6

Kidney maintains the values in the ____ compartment in steady state

Answer 6

Kidney maintains the values in the plasma compartment in steady state

Question 7

___ is the main cation in the extracellular compartment

Answer 7

Na⁺ is the main cation in the extracellular compartment

Question 8

____ concentration controls the volume of the extracellular space

Answer 8

Na⁺ concentration controls the volume of the extracellular space

Question 9

You would want to give IVF to _____, _____, or _____

Answer 9

You would want to give IVF to replete volume (give Na⁺ containing fluid), treat dehydration (give water), and maintenance if person not taking anything in by mouth

Question 10

The calculation for serum osmolality is _______

Answer 10

The calculation for serum osmolality is 2*Na⁺ + BUN/2,8 + glucose/18

Question 11

Normal serum osmolality is ______

Answer 11

Normal serum osmolality is 285-295

Question 12

Types of IVF include _____ or _____

Answer 12

Types of IVF include glucose or Na⁺

Question 13

5% dextrose (D5W) has osmolarity of ______

Answer 13

5% dextrose (D5W) has osmolarity of 278 (near serum)

(sugar is metabolized, leaving only the water to be distributed according to body water distribution)

Question 14

After adding 1L of D5W, there is a _____ mL increase in ICF volume and a _____ mL increase in ECF volume

Answer 14

After adding 1L of D5W, there is a 667 mL increase in ICF volume and a 333 mL increase in ECF volume

(2/3 goes to ICF and 1/3 to ECF b/c near serum osmolality)

Question 15

After adding 1L of D5W, there is a _____ mL increase in plasma volume

Answer 15

After adding 1L of D5W, there is an 83 mL increase in plasma volume

(1/3 goes to ECF and 1/4 of that goes to plasma so (1/3)*(1/4)*1000 = 83)

Question 16

IVF is infused into the _____

Answer 16

IVF is infused into the plasma compartment

(IVF osmolarity should be similar to plasma to avoid injury to cells in plasma)

Question 17

Normal saline is close to _____ with serum

Answer 17

Normal saline (0.9% saline) is close to isotonic with serum

(osmolality of 308 - 154 mEq of Na⁺ and 154 mEq of Cl^-)

Question 18

After adding 1L of normal (0.9%) saline, there is a _____ mL increase in ICF volume and a _____ mL increase in ECF volume

Answer 18

After adding 1L of normal (0.9%) saline, there is a 0 mL increase in ICF volume and a 1000 mL increase in ECF volume

(all of the saline goes to ECF b/c isotonic)

Question 19

After adding 1L of normal (0.9%) saline, there is a _____ mL increase in plasma volume

Answer 19

After adding 1L of normal (0.9%) saline, there is a 250 mL increase in plasma volume

(all of the saline goes to the ECF, and the plasma volume is 1/4 of the ECF volume)

Question 20

After adding 1L of half normal saline (0.45%), there is a _____ mL increase in ICF volume and a _____ mL increase in ECF volume

Answer 20

After adding 1L of half normal saline (0.45%), there is a 333 mL increase in ICF volume and a 667 mL increase in ECF volume

(think of as adding 500 mL pure water and 500 mL normal saline)

Question 21

After adding 1L of half normal saline (0.45%), there is a _____ mL increase in plasma volume

Answer 21

After adding 1L of half normal saline (0.45%), there is a 167 mL increase in plasma volume

(167 + 500 = 667 mL go to ECF and 1/4 of that goes to the plasma)

Question 22

After adding 1L of lactated ringers, there is a _____ mL increase in ICF volume and a _____ mL increase in ECF volume

Answer 22

After adding 1L of lactated ringers, there is a 100 mL increase in ICF volume and a 900 mL increase in ECF volume

Question 23

After adding 1L of lactated ringers, there is a _____ mL increase in plasma volume

Answer 23

After adding 1L of lactated ringers, there is a 225 mL increase in plasma volume

(900 mL goes to ECF and 1/4 of that goes to plasma)

Question 24

All IVF starts in the ______

Answer 24

All IVF starts in the vascular space

Question 25

If IVF contains glucose only, it redistributes according to \_\_\_\_\_

Answer 25

If IVF contains glucose only, it redistributes according to total body water (good for treating dehydration, which is loss of water)

Question 26

Saline containing IVF will stay in the \_\_\_\_\_\_

Answer 26

Saline containing IVF will stay in the ECF (better for treating hypovolemia, which is volume depletion causing issues with perfusion)

Question 27

D5W is good for treating \_\_\_\_\_\_

Answer 27

D5W is good for treating dehydration (loss of water)

Question 28

Saline containing IVF is good for treating \_\_\_\_\_

Answer 28

Saline containing IVF is good for treating hypovolemia (volume depletion causing issues with perfusion)

Question 29

Insensible water loss is water loss that is \_\_\_\_\_\_

Answer 29

Insensible water loss is water loss that is not easily measured (skin, respiratory losses)

Question 30

If a patient is not taking anything by mouth, give \_\_\_\_\_

Answer 30

If a patient is not taking anything by mouth, give D5W

Question 31

If the patient is volume depleted, need \_\_\_\_

Answer 31

If the patient is volume depleted, need Na⁺ (to replete vascular space and assist perfusion)

Question 32

\_\_\_\_\_ is a great choice for volume reuscitation of patients who are volume depleted

Answer 32

Normal saline is a great choice for volume reuscitation of patients who are volume depleted (provides Na⁺ and Cl^- the kidney needs to maintain volume) (lactated ringers also works b/c provides K⁺ and Cl^-)

Question 33

Administer either _____ or _____ for volume depleted patient

Answer 33

Administer either normal saline or lactated ringers for volume depleted patient

Question 34

If someone is volume depleted, you want to cover the _____ but also \_\_\_\_\_

Answer 34

If someone is volume depleted, you want to cover the volume already lost but also ongoing losses

Question 35

Giving normal saline as a maintenance fluid results in a \_\_\_\_\_

Answer 35

Giving normal saline as a maintenance fluid results in a large salt load (lot of Na⁺ in normal saline)

Question 36

If euvolemic and hyperosmotic, give \_\_\_\_

Answer 36

If euvolemic and hyperosmotic, give IV D5W

Question 37

If hypovolemic and hyperosmotic, \_\_\_\_

Answer 37

If hypovolemic and hyperosmotic, replace the volume deficit via a salt-containing solution

Question 38

\_\_\_\_ of Na⁺ is reabsorbed at the PCT, _____ at the TAL, and _____ at the DCT

Answer 38

60% of Na⁺ is reabsorbed at the PCT, 30% at the TAL, and 7% at the DCT

Question 39

\_\_\_\_\_ fine tunes Na⁺ reabsorption

Answer 39

Cortical collecting duct fine tunes Na⁺ reabsorption

Question 40

An example of a proximal tubule diuretic is \_\_\_\_\_\_

Answer 40

An example of a proximal tubule diuretic is acetazolamide

Question 41

Acetazolamide (proximal tubule diuretic) \_\_\_\_\_\_, inhibiting \_\_\_\_\_\_

Answer 41

Acetazolamide (proximal tubule diuretic) inhibits carbonic anhydrase, inhibiting Na⁺ reabsorption, HCO₃^- reabsorption, and H⁺ secretion (carbonic anhydrase promotes absorption of Na⁺ with HCO₃^-)

Question 42

Acetazolamide causes less _____ and _____ reabsorption

Answer 42

Acetazolamide causes less Na⁺ and HCO₃^- reabsorption (acidosis through decreased bicarbonate reabsorption)

Question 43

Describe characteristics of acetazolamide

Answer 43

Characteristics of acetazolamide * Works in proximal tubule * Weak diuretic because the rest of the nephron can compensate for the Na⁺ being lost * Causes a non-anion gap metabolic acidosis * Used to treat metabolic alkalosis, particularly if volume overloaded

Question 44

\_\_\_\_\_, \_\_\_\_\_, and _____ are loop diuretics

Answer 44

Furosemide (Lasix), torsemide (Demadex), and bumetanide (Bumex) are loop diuretics

Question 45

Loop diuretics act in the \_\_\_\_\_

Answer 45

Loop diuretics act in the thick ascending loop of Henle

Question 46

Loop diuretics inhibit the _____ in the \_\_\_\_\_

Answer 46

Loop diuretics inhibit the Na⁺/K⁺/2Cl^- in the thick ascending limb of the loop of Henle

Question 47

Describe characteristics of loop diuretics

Answer 47

Characteristics of loop diuretics * inhibit the Na⁺/K⁺/2Cl^- in the thick ascending limb of the loop of Henle * Side effects: fluid and electrolyte imbalances (hypokalemia, hypocalcemia, hypomagnesemia), volume depletion, ototoxicity, hyperuricemia, hyperglycemia, increased LDL and TG * Used for volume overload (rapid diuresis), HTN particularly in CKD

Question 48

\_\_\_\_\_, \_\_\_\_\_, and _____ are thiazides

Answer 48

Hydrochlorothiazide, chlorthalidone, and metolazone are thiazides

Question 49

Thiazides act in the \_\_\_\_\_

Answer 49

Thiazides act in the distal convoluted tubule

Question 50

Thiazide diuretics inhibit the _____ in the \_\_\_\_\_

Answer 50

Thiazide diuretics inhibit the Na⁺/Cl^- in the distal convoluted tubule

Question 51

Describe characteristics of thiazides

Answer 51

Characteristics of thiazides * Inhibit the Na+/Cl- in the distal convoluted tubule * Side effects: impotence, fluid and electrolyte imbalances (hypokalemia, hyponatremia, hypercalcemia), impaired glucose tolerance, increased cholesterol * First line treatment in HTN

Question 52

\_\_\_\_\_ may cause hypokalemia and hypercalcemia

Answer 52

Thiazides may cause hypokalemia and hypercalcemia

Question 53

\_\_\_\_\_, \_\_\_\_\_, \_\_\_\_\_, and _____ are K⁺ sparing diuretics

Answer 53

Triamterence, amiloride, spironolactone, and eplerenone are K⁺ sparing diuretics

Question 54

K⁺ sparing diuretics act in the \_\_\_\_\_\_

Answer 54

K⁺​ sparing diuretics act in the cortical collecting duct (trap more Na⁺ in urinary space)

Question 55

Trimaterene and amiloride inhibit \_\_\_\_\_\_

Answer 55

Trimaterene and amiloride (K⁺ sparing) inhibit renal epithelial Na⁺ channels in the late distal tubule and collecting duct

Question 56

Spironolactone and eplerenone inhibit the \_\_\_\_\_\_

Answer 56

Spironolactone and eplerenone inhibit the mineralocorticoid receptor on epithelial cells in the late distal tubule and cortical collecting duct

Question 57

Describe side effects of K⁺ sparing diuretics

Answer 57

Side effects of K⁺​ sparing diuretics * Amiloride and triamterence: hyperkalemia, nausea, vomiting * Spironolactone: hyperkalemia, gynecomastia (adjunctive treatment with other diuretics to avoid hypokalemia)

Question 58

Describe the main points about diuretics

Answer 58

Diuretics * Evoke natriuresis through inhibition of ion channels in different sections of the nephron * Lower blood pressure by decreased intravascular volume, vasodilation with chronic use * Main side effects are electrolyte abnormalities and volume depletion