Magnesium

Question 1

What two other electrolytes should be assessed with magnesium?

Answer 1

Calcium and potassium

Question 2

Magnesium concentration is regulated by ___ and ___

Answer 2

Magnesium concentration is regulated by GI absorption and Kidney excretion

Question 3

Which electrolyte imbalances show similar symptoms to magnesium imbalances

Answer 3

Calcium

Question 4

Hypermagnesemia typically occurs due to: 2

Answer 4

Increased magnesium intake
Renal insufficiency/failure

Question 5

Clinical manifestation of hypermagnesemia

Answer 5

Excessive magnesium inhibits acetylcholine release and calcium movement into the cells, impairing nerve and muscle function.

Initial manifestations include:
- Hypotension
- Lethargy
- Urine retention
- N+V

As serum levels elevate…
- Deep tendon reflexes are lost
- Muscle paralysis
- Coma
- Respiratory & cardiac arrest can occur

Question 6

Management of Hypermagnesemia

+ What to do if it is way too high to avoid cardiac complications

Answer 6

Avoiding high-magnesium-containing foods
If renal function is adequate, increase fluid and diuretics to promote urinary excretion

IV calcium gluconate opposes the effects of the excess magnesium on cardiac muscle

Question 7

Causes of hypomagnesemia

Answer 7

Insufficient magnesium intake
- prolonged fasting
- starvation
- alcoholism

Real or GI losses
- vomiting
- diarrhea

Question 8

Manifestation of hypomagnesemia

Answer 8

Neuro-muscular manifestations are common
Muscle cramps
Tremors
Hyperactive deep tendon reflexes
Seizures
Cardiac dysrhythmias

Question 9

Management of hypomagnesemia

Answer 9

Can be treated with oral supplements and increased dietary intake

If the condition is severe, IV or IM magnesium can be administered.