Lecture 5 Electrolyte Imbalances

Question 1

how are electrolytes measured?

Answer 1

based on extracellular (serum) concentration of electrolytes in blood

Question 2

what is the most abundant electrolyte in extracellular fluid?

Answer 2

sodium

Question 3

what does sodium do?

Answer 3

muscle contraction and nerve impulses

Question 4

what does calcium do?

Answer 4

transmits nerve impulses
regulates muscle contraction ad relaxation
cardiac conduction
blood coagulation
bone mineralization

Question 5

where is potassium mostly concentrated?

Answer 5

98% is intracellular

Question 6

what does potassium do?

Answer 6

conduction of nerve cells - skeletal muscle and cardiac muscle

Question 7

what does magnesium do?

Answer 7

neuromuscular function - contraction and relaxation
vasodilation

Question 8

causes of hyponatremia

Answer 8

diuretics
vomiting
kidney and liver issues
polydipsia
diarrhea

Question 9

signs and symptoms of hyponatremia

Answer 9

neuro = lethargy, headache, confusion
seizures
gait disorders
nausea and vomiting
muscle weakness and spasms

Question 10

hyponatremia treatment

Answer 10

sodium by mouth and 1-1.5 L fluid restriction
isotonic IV solution
Hypertonic solution for severe neuro changes
no more than 12 mEq sodium in 24 hours

Question 11

hypernatremia

Answer 11

gain of excess sodium or excessive loss of water

Question 12

causes of hypernatremia

Answer 12

• fluid deprivation
• sodium intake
• sodium retention with water loss
• fluid losses (diabetes insipidus)
• hyperventilation

Question 13

signs and symptoms of hypernatremia

Answer 13

thirst
muscle weakness
dry mucous membranes
decreased UOP
mild fever
hallucinations and seizure

Question 14

what is used to treat hypernatremia

Answer 14

hypotonic IV fluids
furosemide or thiazide

Question 15

causes of hypokalemia

Answer 15

• increased potassium output, decreased intake
• too much insulin
• magnesium depletion
• increased aldosterone
• potassium wasting diuretics - furosemide, thiazide

Question 16

signs and symptoms of hypokalemia

Answer 16

• arrhythmias, tachycardia
• muscle and GI cramping
• hypotension
• weakness
• respiratory depression

Question 17

treating hypokalemia

Answer 17

• oral potassium supplement
• potassium IV infusion 10-20 mEq/hr, NEVER IV PUSH
• cardiac monitoring during infusion

Question 18

causes of hyperkalemia

Answer 18

• potassium sparing diuretics
• acidosis
• cellular injury (because potassium more abundant intracellularly)
• low aldosterone
• renal failure with increased potassium intake

Question 19

what does aldosterone do to potassium?

Answer 19

causes excretion of potassium
too much aldosterone = hypokalemia
too little aldosterone = hyperkalemia

Question 20

signs and symptoms of hyperkalemia

Answer 20

• muscle twitching
• irritability
• low BP
• dysrhythmias
• abdominal cramping
• diarrhea

Question 21

treating hyperkalemia

Answer 21

diet restriction
calcium gluconate
sodium bicarbonate
IV insulin
loop diuretics - potassium wasting
dialysis if severe

Question 22

how is low calcium regulated?

Answer 22

• low calcium prompts parathyroid to release PTH
• draws calcium out of bones and tells kidneys and intestines to reabsorb calcium

Question 23

how is high calcium regulated?

Answer 23

• thyroid gland releases calcitonin
• inhibits calcium reabsorption from bone
• encourages calcium to be deposited in bones or excreted

Question 24

what is the relationship between calcium and phosphorus

Answer 24

inverse
less calcium = more phosphorus
more calcium = less phosphorus

Question 25

causes of hypocalcemia

Answer 25

• inadequate intake
• calcium malabsorption
• inadequate parathyroid hormone
• vitamin D deficiency

Question 26

signs and symptoms of hypocalcemia

Answer 26

• neuromuscular hyperactivity, spasms
• arrhythmias
• numbness and tingling
• seizures
• dyspnea

Question 27

treating hypocalcemia

Answer 27

calcium carbonate antacid - lower phosphorus
vitamin D supplements
IV calcium gluconate - infusion pump

Question 28

causes of hypercalcemia

Answer 28

• malignancies - bone metastases
• too much parathyroid hormone
• lithium and thiazide diuretics

Question 29

signs and symptoms of hypercalcemia

Answer 29

• bone pain
• kidney stones
• abdominal pain, N/V, constipation
• anxiety, fatigue, psychosis, depression
• decreased deep tendon reflex
• cardiac arrhythmias

Question 30

how does calcium affect bleeding?

Answer 30

hypocalcemia = bleeding risk
hypercalcemia = clotting risk

Question 31

treating hypercalcemia

Answer 31

• treat malignancy
• restrict dietary intake
• loop diuretics
• IM calcitonin to encourage reabsorption
• dialysis
• sodium containing fluids

Question 32

causes of hypomagnesemia

Answer 32

ETOH
malnutrition
diarrhea
DKA
loop and thiazide diuretics

Question 33

signs and symptoms of hypomagnesemia

Answer 33

• muscle weakness and cramping
• disorientation, vertigo
• cardiac arrhythmias
• associated with hypokalemia and hypocalcemia

Question 34

managing hypomagnesemia

Answer 34

• diet - green veg, PB, nuts, legumes
• oral magnesium salts
• magnesium sulfate IV

Question 35

causes of hypermagnesemia

Answer 35

renal failure
tissue trauma: DKA, rhabdomyolysis
lithium
laxatives
opioids
anticholinergics

Question 36

signs and symptoms of hypermagnesemia

Answer 36

• CNS and nerve depression - weakness, dizziness, confusion
• vasodilation and dysrhythmias = hypotension
• respiratory depression
• Lost DTR and paralysis = coma
• cardiac arrest