Lecture 2 - Magnesium

Question 1

Normal Mg range: ___ mg/dL

Answer 1

1.5-2.5

Question 2

magnesium 1.5-2.5 mg/dL

• important role in ___ function
• Co-factor for many enzymes: ATP, Alkaline ___
• Needed for stabilizing macromolecular structures such as ___
• related to ___ and ___ metabolism
• regulated by intake and kidney ___

Answer 2

• neuromuscular
• phospatase
• DNA/RNA
• Ca, K
• excretion

Question 3

hypomagnesemia causes

• associated with disorders of ___ or ___
• diarrhea
• decreased intestinal absorption
• severe malnutrition
• drugs (amphotericin, aminoglycosides, ___ thiazide or ___, and cyclosporine)
• alcohol

Answer 3

• GI tract, kidneys
• diuretics, loop

Question 4

T or F: it is easy to isolate Mg

Answer 4

F

Question 5

clinical presentation of hypomagnesemia

• often associated with hypo___ and hypo ___
• cadiovascular: tetany, generalized convulsions, ___ arrhythmias
• neuromuscular: ataxia, fasculations, ___
• CNS: lethargy, ___, nystagmus

Answer 5

• hypocalcemia, hypokalemia
• ventricular
• seizures
• confusion

Question 6

when treating hypmagnesemia, dont forget to treat …

Answer 6

associated electrolyte disturbances

like hypocalcemia and hypokalemia

Question 7

Treatment of hypomagnesemia

PO - asymptomatic pts with Mg > ___ mg/dL
- ___ 5-10 mL PO QID
- ___ 800 mg PO d or 400 mg PO TID with meals

Answer 7

1
* Milk of Mag
* Mag-Ox

Question 8

Treatment of hypomagnesemia

IV - symptomatic pts
- goal in ICU may be higher ( ___ mg/dL)
- Mg 1-2 mg/dL: ___ mEq/kg
- Mg < 1 mg/dL: ___
- ___ mEq = 1 gram
- infused ___ gram per hour

Answer 8

• 2 mg/dL
• 0.5 mEq/k
• 1 mEq/k
• 8 mEq
• 1 gm

most pts need around 4 grams

Question 9

Hypermagnesemia

• ___ occurence
• ___ failure/insufficiency
• excessive intake of Mg through Mg containing ___, treatment of ___

Answer 9

• rare
• renal
• laxatives, eclampsia

Question 10

Clinical Presentation of hypermagnesemia

Concentrations above > ___ mg/dL

Neuromuscular
- loss of deep tendon reflexes
- drowsiness, lethargy, somnlence
- respiratory muscle paralysis

Cardiovascular
- hypotension
- cardiac rhythm abnormalities
- complete heart block

Answer 10

4 mg/dL

Question 11

Hypermagnesemia treatment

___ 1-2 grams IVP x1 and repeat prn

adequate renal function
* IV hydration with NS or 1/2NS infused at 200 mL/hr + 1-2 gm CaCl per above
* IV ___

Renal Dysfunction
- forced ___
- hemodialysis

Supportive care (as needed)
- cardiac pacing
- ___
- mechanical ventilation

Answer 11

calcium chloride
- furosemide
- diuresis
- vasopressors