Fluids & Electrolytes

Question 1

What is the first step in evaluating a patient with hyponatremia?

Answer 1

Determining their volume statu

Question 2

What is the most common cause of hypovolemic hyponatremia?

Answer 2

Intravascular volume depletion “dehydration”

Question 3

What is the most common cause of hypervolemic hyponatremia?

Answer 3

Heart failure with total body fluid overload

Question 4

What are the two most common causes of euvolemic hyponatremia

Answer 4

1. Hypoosmolar hyponatremia (malnutrition)

2. Syndrome of Inappropriate Anti-diuretic Hormone (SIADH)

Question 5

What are two common causes of SIADH?

Answer 5

1. CNS disturbances
2. Major surgery (especially neurosurgery)
3. Trauma (especially to the head)
4. Pulmonary disturbances (tumors, infections, inflammatory reactions)
5. Malignancy

Question 6

What are the symptoms of severe hyponatremia? (name 3)

Answer 6

1. Headache
2. Decreased mental status (Lethargy/Obtunded/Coma)
3. Confusion
4. Seizure

Question 7

What is the risk of too rapid correction of hyponatremia?

Answer 7

Cerebral Osmotic Demyelination (COD)

Question 8

What is typically the treatment of mild to moderate hypovolemic hyponatremia

Answer 8

Intravenous normal saline (0.9% sodium)

Question 9

What is typically the treatment of acute severe hyponatremia?

Answer 9

Hypertonic saline infusion (3% sodium)

Question 10

What is the most common cause of hypoosmolar hyponatremia

Answer 10

Malnutrition (often due to alcoholism)

Question 11

What is typically the treatment of SIADH?

Answer 11

Free water restriction

Question 12

What is typically the treatment of hypervolemic hyponatremia?

Answer 12

Diuretics

Question 13

What is the maximum rate of correction of hyponatremia?

Answer 13

8 mEq/L in 24hr

Question 14

What is the most common cause of hypernatremia?

Answer 14

Free water deficit (true dehydration)

Question 15

What is typically the treatment of hypernatremia?

Answer 15

D5W (dangerous to give intravenous free water)

*Calculate the free water deficit

Question 16

A patient presents to the office complaining of muscle cramping, fatigue and heart palpitations. He recently was started on a medication to treat leg swelling. What is the most likely electrolyte abnormality?

Answer 16

Hypokalemia

Question 17

How do you treat mild and severe hypokalemia

Answer 17

Mild - Oral potassium
Severe - Oral and IV potassium together
*Ensure Magnesium is optimized

Question 18

What is the EKG findings of Hypokalemia?

Answer 18

Flattened T waves (possibly U wave)

Question 19

A patient with chronic renal dysfunction presents with heart palpitations after starting a new medication for HTN. What is the most likely electrolyte abnormality?

Answer 19

Hyperkalemia

Question 20

What EKG finding is expected in severe hyperkalemia?

Answer 20

Peaked T waves, sine waves –> can lead to Ventricular tachycardia

Question 21

What is the treatment of mild hyperkalemia?

Answer 21

Oral Kayexalate

Question 22

What is the treatment of severe hyperkalemia?

Answer 22

IV calcium gluconate plus regular IV insulin

Question 23

What are the common causes of hypocalcemia? (name 3)

Answer 23

1. Parathyroid disease
2. Parathyroidectomy
3. Vitamin D deficiency
4. Other malnutrition - poor intake

Question 24

What are symptoms of severe hypocalcemia? (name 3)

Answer 24

1. Parasthesia
2. Hyperreflexia
3. Tetany
4. Muscle cramps
5. Seizure

Question 25

Describe Chvostek sign

Answer 25

Facial spasm following the percussion of the facial nerve

Question 26

Describe Trousseau’s sign

Answer 26

spasm of the hand elicited by inflation of a BP cuff

Question 27

A patient with an osteocarcoma presents with fatigue, muscle weakness and confusion. What electrolyte disorder does she have?

Answer 27

Hypercalcemia