Electrolytes

Question 1

What is tonicity

What are the most effective Osmols

Types?

Answer 1

Osmotic pressure caused by particle restriction to one side of the cell membrane

sodium and glucose

Hypertonic, isotonic, hypotonic

Question 2

What is the most common type of electrolyte disturbance

Answer 2

hyponatremia

Question 3

What is isotonic hyponatremia

What causes it

Answer 3

hyponatremia with normal osmolality

increased number of proteins & lipids in the plasma

elevated LDL, hyperproteinemia from multiple myelosis, elevated triglycerides

Question 4

How do you treat isotonic hyponatremia

What is used to treat LDL

Answer 4

1. treat hypertriglyeridemia or LDL
2. Treat the multiple myeloma (immunotherapy)

statins, fibrates, niacin, fish oil

Question 5

What is another name for hypertonic hyponatremia

Answer 5

translational hyponatremia

Question 6

What is the main cause of hypertonic hyponatremia

other common causes

Answer 6

Hyperglycemia

mannitol, sorbitol, contrast

Question 7

What are the different types of hypotonic hyponatremia

Answer 7

hypovolemic
euvolemic
hypervolemic

Question 8

What are the causes of hypovolemic hypotonic hyponatremia

Answer 8

Extra renal/ renal salt loss

Question 9

What causes extra renal salt loss

Answer 9

dehydration
diarrhea
vomiting

Question 10

What causes renal salt loss

Answer 10

Diuretics
ACEi
Kidney disease
mineralcorticoid deficiency
cerebral salt wasting

Question 11

What are the common causes of euvolemic hypotonic hyponatremia

Answer 11

SIADH
Adrenal insufficiency
Thiazides
NSAIDs
hypothyroidism
post-op
ecstasy
beer potomania

Question 12

What are some causes of hypervolemic hypotonic hyponatremia

Answer 12

Cirrhosis
Heart failure
Nephrotic syndrome
AKD

Question 13

What are some severe symptoms of hyponatremia

Mild to moderate?

Answer 13

Seizures, coma, respiratory arrest

H/A, N/V, ataxia, confusion, muscle cramps, dizziness, lethargy

Question 14

What level is considered severe hyponatremia

Answer 14

<120

Question 15

What is the primary treatment of hypotonic hyponatremia

Answer 15

restriction of free water or hypotonic solution

Question 16

What is the treatment of hypovolemic hypotonic, hyponatremia

Answer 16

volume resuscitation with LR (isotonic fluids)

Question 17

What is the treatment for hypervolemic hypotonic hyponatremia

Answer 17

reeduce volume with diuresis

Question 18

What is osmotic demyelination syndrome

When does it present

Answer 18

rapid rise in sodium concentration pulls water from the brain resulting in cerebral demyelination

2-3 days after sodium correction

Question 19

What are the symptoms of osmotic demyelination syndrome

Answer 19

dysphagia
aphagia
locked-in syndrome
coma
weakness/paralysis in extremities
confusion
stiffness

Question 20

What is the treatment for osmotic demyelination syndrome

Answer 20

supportive case
IV NS / D5
DDAVP
plasmapheresis

Question 21

What is hypernatremia

Answer 21

Serum sodium >145
always hyperosmolar state

Question 22

What are the primary causes of hypernatremia

Answer 22

Free water loss
excessive sodium intake
hospitalized w/o free water access
primary hyperaldosteronism

Question 23

What are the symptoms of hypernatremia

Answer 23

Signs of dehydration (orthostasis, oliguria)
lethargy, weakness, irritability
hyperthermia, delirium, coma if severe

Question 24

When looking at fractional sodium excretion, what does FENa<1% indicate

What are the causes

Answer 24

extrarenal losses

vomiting, diarrhea, sweating, burns, pulmonary losses

Question 25

When looking at fractional sodium excretion, what woul FENa>1% indicate

What are the causes

Answer 25

Renal losses

diuretics, mannitol, renal failure, hyperglycemia

Question 26

How do you treat someone with hypernatremia

Answer 26

Admit and treat any fluid loss or electrolyte imbalance

Question 27

What is the function of potassium in the body

Answer 27

maintain ICF
maintain electrochemical gradient
muscle contraction
balance pH
nerve signal transmission
cardiac refractory period

Question 28

What is hypokalemia due to

Answer 28

inadequate intake
movement of K+ from ECF-> ICF
extra renal K+ loss
Renal K+ loss

Question 29

What are the symptoms of hypokalemia

Answer 29

Muscle weakness, fatigue, muscle cramps, constipation/ileus

Question 30

If hypokalemia is severe, what are the symptoms

Answer 30

Flaccid Paralysis
hyporeflexia
hypercapnia
tetany
rhabdomyolysis

Question 31

If urinary potassium concentration is <20, where are the losses coming from

if >40??

Answer 31

extra renal loss

renal loss

Question 32

What are some characteristic EKG finding with hypokalemia

Answer 32

broadening T waves
Prominent U waves
PVC
Depressed ST segment

Question 33

What are the causes of hyperkalemia

Answer 33

renal disease
Shift of K+ from ICF to ECF
Excessive K+ intake
psuedohyperkalemia

Question 34

What are characteristic EKG findings with hyperkalemia

Answer 34

bradycardia
prolonged PR interval
Peaked T waves
QRS widening
Biphasic QRS complexes

**leads to Vfib +/- cardiac arrest

Question 35

How do you treat a hyperkalemic emergency

Answer 35

calcium
insulin, sodium bicarb, albuterol
dialysis
potassium binding medications
Diuretics

Question 36

What is magnesium used for in the body

Answer 36

protein synthesis
muscle / nerve function
glucose / BP regulation
Energy production
Active role in active transport of Ca and K

Question 37

What are the causes of hypomagnesemia

Answer 37

Reduced absorption intake
increased renal losses
DM
respiratory alkalosis
pregnancy
post-parathyroidectomy

Question 38

What can hypomagnesemia lead to/cause

Answer 38

Hypocalcemia
hypokalemia