PHRM 825: Fluids and Electrolytes - Electrolytes - Ca+2 Flashcards
Normal Ca+2 blood levels
8.5-10.5 mg/dL
Calcium is necessary for ____ formation and _____ funciton
bone and neuromuscular
Calcium serum concentrations are controlled mainly by what 3 things?
parathyroid hormone, vitamin D, and calcitonin
Organs involved in calcium metabolism include
bone, kidneys, and the intestine
Causes of hypocalcemia (7)
- Magnesium deficiency
- Large volumes of blood products
- Hypoalbuminemia
- Post-op hypoparathyroid
- Vitamin D deficiency
- Thyroid surgery
- Medications
Hypocalcemia is typically seen in what kinds of patients?
Hospital patients
Corrected calcium equation
Corrected Ca+2 = measured Ca+2 + [(4 - measured albumin) x 0.8]
When available, you should use the _____ over the corrected calcium calculation
ionized calcium level
Normal ionized calcium levels
4.6-5.1 mg/dL (milligram, NOT milliequivalents)
What does ionized calcium levels represent?
The amount of calcium available for use in the body
Clinical presentation of hypocalcemia in the neuromuscular system
- Parasthesias
- Muscle cramps
- Tetany
Clinical presentation of hypocalcemia in the CNS
- Depression
- anxiety
- Memory loss
- Confusion
- Hallucination
- Seizures
Clinical presentation of hypocalcemia in the dermatologic system
- Hair loss
- Grooved brittle nails
- Eczema
Clinical presentation of hypocalcemia in the cardiac system
-Prolonged QT Decreased myocardial contractility -Arrhythmias -Bradycardia -Hypotension
Acute treatment of hypocalcemia
- 100-300 mg of elemental Ca+2 IV oer 5-10 minutes
- Usual administration rate for Ca+2 is 1 gm/hr
- Correct hypomagnesemia
What should you NEVER give a patient when giving calcium to treat hypocalcemia?
Bicarb or phos solutions (It will precipitate and create chalk in the bloodstream)
1 g CaCl = ____ g Ca gluconate
3
1 g CaCl= ____ mg elemental calcium
270
3 g Ca gluconate = ____ mg elemental calcium
270
Calcium chloride can be administered PIV when?
During a code (cardiac arrest)
Calcium gluconate is preferred for ____
PIV administration
What aspects of calcium gluconate make it preferred for PIV administration
- Lower percentage of elemental Ca+2
- Less predictable increase in Ca+2 concentration
- Less risk for extravasation
Chronic treatment of hypocalcemia
- PO calcium
- Vitamin D supplementation
PO calcium treatment for hypocalcemia
-1-3 g/day of elemental Ca+2
1 g elemental Ca+/day is equivalent to _____ of CaCO3
650 mg PO QID
Vitamin D supplementation for hypocalcemia
- Calcitriol 0.25 mcg PO daily or every other day
- May need to increase by 0.25 mcg q 4-8 weeks to 1 mcg PO daily
Hypercalcemia is typically present in what 2 disease states?
Cancer and hyperparathyroidism
3 mechanisms that lead to hypercalcemia
- Increased bone resorption
- Increased gastrointestinal absorption
- Decreased elimination by the kidneys
Hypercalcemia is often ____ especially when serum calcium is ____
asymptomatic; <13 mg/dL
Clinical presentation of acute onset of hypercalcemia
- Anorexia
- Nausea
- Vomiting
- Constipation
- Polyuria
- Polydipsia
- Nocturia
Clinical presentation of hypercalcemic crisis
- ARF
- Obtundation
- Coma
- Life-threateing arrhythmias
Hypercalcemic crisis is characterized by calcium concentration of ___
> 15 mg/dL
Clinical presentation of chronic hypercalcemia
- Metastatic calcification
- Nephrolithiasis
- CRF
Goals of treatment for hypercalcemia
- Reverse signs and symptoms
- Restore to normal calcium concentrations
- Identify and treat the underlying cause(s)
- Prevent long term consequences, renal insufficiency
Treatments for hypercalcemia
- Volume expansion/loop diuretics
- Calcitonin
- Bisphosphonates
- Glucocorticoids
Volume expansion/Loop diuretics should be used to treat hypercalcemia when renal function is ____
normal to moderately impaired
Volume expansion/loop diuretics should be used in ____ patients that have ____
symptomatic patients; hypercalcemia
In hypercalcemia, symptomatic patients are often _____ because of ___
dehydrated; vomiting/ polyuria
When administering NS to treat _____, you should monitor ____
hypercalcemia; ins and outs or CVP
How does furosemide help treat hypercalcemia
- Increases Ca+ urinary excretion
- Minimizes volume overload
Calcitonin should be used to treat _____ in patients with _____
hypercalcemia; moderate to severe renal dysfunction or CHF
Calcitonin _____ serum Ca+2 by ____
reduces; inhibiting bone resorption and reducing renal tubular reabsorption
How do bisphosphonates help treat hypercalcemia
Prevent bone reabsorption
_____ bisphosphonate is more effective at reducing Ca+2 levels than ____ bisphosphonate
Pamidronate; etidronate
Bisphosphonates cause Ca+2 concentrations to decline in ____ days
~2
Glucocorticoids can be used to treat hypercalcemia in patients caused by
- Multiple myeloma
- Leukemia
- Lymphoma
- Sarcidosis
How do glucocorticoids treat hypercalcemia
- Decrease GI absorption
- Interfere with vitamin D metabolism (increases bone resorption and decreased osteoblast proliferation)
Glucocorticoids have a ____ onset and increase the risk of ____ or _____
Onset; hyperglycemia or infection