3-4

Question 1

Hyponatremia is when serum Na is less than ___

Answer 1

135 mEq/L

Question 2

Severe symptoms of hyponatremia

Answer 2

Vomiting
Cardiorespiratory arrest
Seizures
Reduced consciousness/coma (Glasgow <8)

Question 3

ADH/vasopressin is synthesized in the ___

Answer 3

Hypothalamus

Question 4

Normal serum osmolality is ___

Answer 4

280-295

2Na + glucose/18 + BUN/2.8

Question 5

1. Hypertonic hyponatremia
2. Isotonic
3. Hypotonic

Answer 5

1. Hyperglycemia, glucose, mannitol, maltose
2. Pseudo, hyperlipidemia, hyperproteinemia
3. Most common

Question 6

[Na] =
Hypotonic hyponatremia: volume assessment:
1. Hypovolemia
2. Hypervolemia
3. Iso/Euvolemia

Answer 6

Na/TBW

1. ⬇️⬇️Na, ⬇️H2O
2. ⬆️Na, ⬆️⬆️H2O
3. ⬆️H2O

Question 7

Hypotonic hyponatremia: volume assessment:

1. Hypovolemia with urine Na:
   a. >20
   b. <20
2. Euvolemia ALWAYS has urine Na >20
3. Hypervolemia with urine Na:
   a. >20
   b. <20

Answer 7

1. a. Renal solute loss
   b. Extrarenal solute loss
2. SIADH, Endocrinopathies (glucocorticoid deficiency), or K depletion (ex: from diuretic use)
3. a. Renal failure
   b. Edematous disorders (HF, cirrhosis, nephrotic syndrome)

Question 8

SIADH causes:

Answer 8

CNS disorders
Pulmonary disease
Small cell lung cancer 
Drugs
Hypothyroidism

Question 9

SIADH vs Psychogenic polydipsia

Answer 9

-not dilute urine vs. dilute urine

Question 10

Hyponatremia:
Acute
Subacute
Chronic

Answer 10

<24 hrs
24-48
>48

Question 11

Fluid replacement options for hyponatremia:

Answer 11

1. Normal Saline (9%, 154 mEq of Na)
2. Lactate ringers (130 mEq)
3. Hypertonic saline (3%, 513 mEq) *used for severe cases

Question 12

Goal of treatment for hyponatremia is to raise Na by ___, not to exceed ____. Measure serum Na every ____

Answer 12

4-6 mmol/L/24 hours
8 mEq in 24 hours
2 hours

Question 13

Rapid correction of hyponatremia can lead to ___

Answer 13

Osmotic demyelination syndrome (ODS)

Question 14

ODS presentation:

Answer 14

Paresis
Dysphagia
Dysarthria
Diplopia
Loss of consciousness
Ataxia
Parkinsonism

Question 15

Tx of choice for

1. Euvolemia hyponatremia
2. Hypovolemic hyponatremia
3. Hypervolemic hyponatremia

Answer 15

1. Free water restriction
2. Isotonic/hypertonic saline
3. Na and fluid restriction
   - if CHF: add loop diuretics and ACEI/ARB

Question 16

Furosemide

1. What is it?
2. Indication?
3. Where does it act?
4. MOA?
5. Cautions?
6. Onset?
7. Duration?

Answer 16

1. Loop diuretics
2. Hypervolemia
3. Ascending loop of Henle
4. Inhibits Na-K-Cl transport system
5. Hypokalemia
6. PO 30-60 min, IV 5 min
7. PO 6-8 hrs, IV 2 hrs

Question 17

Desmopressin

1. What is it?
2. MOA?
3. Should avoid in ___

Answer 17

1. Synthetic analogue of ADH
2. Increases cAMP in renal tubular cells which increases H2O permeability = decreased urine volume, increased urine osmolality
3. Psychogenic polydipsia, CHF, cirrhosis

Question 18

Tolvaptan

1. MOA
2. Uses
3. Do not use for more than ___
4. Black box warning
5. Contraindications

Answer 18

1. Selective V2 receptor antagonist
   - increases urine output, decreases urine osmolality, normalizes serum Na
2. Hypervolemic or Euvolemia hyponatremia
3. 30 days
4. Only use in a hospital with serum Na monitoring
5. Liver disease

Question 19

Conivaptan

1. MOA
2. Uses
3. Route

Answer 19

1. Blocks V1a and V2 receptors
2. Euvolemia and hypervolemic hyponatremia in hospital pts
3. IV

Question 20

V2 receptors are predominantly located in the ___

Answer 20

Distal tubule and collecting ducts

Question 21

Things that may cause isosmotic volume contraction:

Answer 21

Diarrhea
Vomiting
Burns

Question 22

How would you treat isosmotic volume contraction?

Answer 22

Isotonic fluids

Question 23

Things that may cause hyperosmotic volume contraction:

Answer 23

Severe dehydration
Drinking cessation
Severe exercising
Diabetes insipidus

Question 24

How would you treat hyperosmotic volume contraction?

Answer 24

hyposmolar or isosmolar IV fluids

Dextrose 5

Question 25

Things that may cause hyposmotic volume contraction:

Answer 25

Adrenal insufficiency -Decrease in aldosterone excess Na loss in the urine

Question 26

How would you treat hyposmotic volume contraction?

Answer 26

Corticosteroids (allow reabsorption of free water and Na)

Question 27

Things that may cause isosmotic volume expansion:

Answer 27

Isotonic saline infusion | Too high fluids running while in the hospital

Question 28

How would you treat isosmotic volume expansion?

Answer 28

Fluid restriction

Question 29

Things that may cause hyperosmotic volume expansion:

Answer 29

Eating high Na foods

Question 30

How would you treat hyperosmotic volume expansion?

Answer 30

Cut back on salty foods

Question 31

Things that may cause hyposmotic volume expansion:

Answer 31

SIADH

Question 32

How would you treat hyposmotic volume expansion?

Answer 32

Fluid restriction Vapton drugs *DO NOT GIVE HYPEROSMOTIC FLUIDS OR GIVE RAPID Na REPLACEMENT! You could give them ODS*

Question 33

ECFV ⬇️ Osmolarity - ICFV -

Answer 33

Isosmotic volume contraction

Question 34

ECFV ⬇️ Osmolarity ⬆️ ICFV ⬇️

Answer 34

Hyperosmotic volume contraction

Question 35

ECFV ⬇️ Osmolarity ⬇️ ICFV ⬆️

Answer 35

Hyposmotic volume contraction

Question 36

ECFV ⬆️ Osmolarity - ICFV -

Answer 36

Isosmotic volume expansion

Question 37

ECFV ⬆️ Osmolarity ⬆️ ICFV ⬇️

Answer 37

Hyperosmotic volume expansion

Question 38

ECFV ⬆️ Osmolarity ⬇️ ICFV ⬆️

Answer 38

Hyposmotic volume expansion