Calcium

Question 1

… is the most abundant mineral in human body

Answer 1

Ca

Question 2

Excretion of [Ca2+] is primarily via the.

Answer 2

stool

Question 3

Hypocalcemia is defined by an ionized [Ca2+] level

Answer 3

Normal ionized [Ca2+] is 2.1 to 2.6 mEq/L (1.05 to 1.3 mmol/L).

Question 4

common causes of hypocalcemia are (4)

Answer 4

1 shock,
2 sepsis,
3 renal failure
4 pancreatitis.

Question 5

Drugs that Can Cause Hypocalcemia

Answer 5

Phosphates (e.g., enemas, laxatives)
Phenytoin, phenobarbital
Gentamicin, tobramycin, actinomycin
Cisplatin
Heparin
Theophylline
Protamine
Glucagon
Norepinephrine
Citrate
Loop diuretics
Glucocorticoids
Magnesium sulfate
Sodium nitroprusside

Question 6

Neurologic signs and symptoms of hypocalcemia

Answer 6

1  Tetany
2  Chvostek sign, 3Trousseau sign
4 Circumoral and digital paresthesias
5  Impaired memory, 
6 confusion
7 Hallucinations, dementia, seizures
8 Extrapyramidal disorders

Question 7

The most characteristic ECG finding in hypocalcemia is a

Answer 7

prolonged QT interval

Question 8

With severe acute hypocalcemia, 10 mL of…. (or 10 to 30 mL of ….) may be given IV over 10 to 20 minutes followed by a continuous IV infusion of …. at ….

Answer 8

10% CaCl2

10% [Ca2+] gluconate

10% CaCl2

0.02 to 0.08 mL/kg/h (1.4 to 5.6 mL/h in a 70-kg patient)

Question 9

IV [Ca2+] should be used with extreme caution in patients taking…., because hypercalcemia can potentiate …. toxicity

Answer 9

digitalis

digitalis

Question 10

During massive transfusions, if the blood is being given faster than …, 10 mL of 10% CaCl2 can be given after every … units of blood

Answer 10

1 unit every 5 minutes

4 to 6

Question 11

the most likely underlying presentation of hypercalcemia in the ED is…

Answer 11

Malignancy

Question 12

Common ED etiologies of hypercalcemia

Answer 12

1 Malignancy*
  Lung (squamous cell cancer)
  Breast
  Kidney
  Myeloma
  Leukemia
2 Lithium
3 Granulomatous disease*
  Sarcoidoses
  Tuberculosis
  Histoplasmosis
  Coccidioidomycosis

Question 13

Drugs that can cause hypercalcemia (4)

Answer 13

Hypervitaminosis D and A
Thiazides
Lithium*
Hormonal therapy for breast cancer

Question 14

Hypercalcemia should be suspected in patients with extensive metastatic bone disease, particularly if the primary site involves the (3)

Answer 14

breast, lungs, or kidneys

Question 15

mnemonic sometimes used for the signs and symptoms of hypercalcemia is

Answer 15

stones (renal calculi), bones (osteolysis), moans (psychiatric disorders), and groans (peptic ulcer disease, pancreatitis, and constipation).

Question 16

On ECG, hypercalcemia may be associated with (4)

Answer 16

1 depressed ST segments,
2 widened T waves,
3 shortened ST segments and QT intervals

Question 17

Hypercalcemia Rx

Answer 17

1 usual first-line therapy for severe hypercalcemia is IV rehydration with normal saline (2-4 L/day for 1-3 days)
2 medications for severe hypercalcemia or inadequate response to IV hydration may include
- bisphosphonates (such as zoledronic acid 4 mg or pamidronate 60-90 mg) IV
- calcitonin 4 units/kg intramuscularly or subcutaneously, especially if rapid onset of action is desired
- glucocorticoids IV for hypercalcemia due to vitamin D excess, granulomatous disease, or hematologic malignancies