Calcium Disorders Flashcards
calcium function
- coagulation
- heart rhythm
- muscle contraction
calcium in blood
majority is unionized (bound to albumin)
only the ionized form is active
normal Ca values
total Ca: 9-11 mg/dL
ionized Ca: 1.1-1.45 mg/dL
most chem panels measure total Ca but not a clinically relevant value - want ionized Ca2+
causes of hypocalcemia
- eclampsia
- chronic kidney disease
- pancreatitis
- critical illness
- iatrogenic
eclampsia
most common cause
postpartum hypocalcemia associated with high lactation demand (usually pre-weaning)
signalment of eclampsia
female dogs
NOT reported in cats
treatment of eclampsia
- IV calcium
- client education: switch puppies to milk replacer, free-feed mom high quality puppy food +/- Ca supplement
clinical signs of hypocalcemia
mild: none, incidental on labs
moderate: facial rubbing, muscle tremors, “tetany”
severe: seizures, obtundation, cardiac dysrhythmias, death
hypocalcemia treatment
ONLY treat cases showing clinical signs
- IV calcium
- 10% Ca gluconate or chloride
ALWAYS monitor ECG for bradyarrhythmias and stop treatment if noted
causes of hypercalcemia
HARD ION
H: hyperparathyroidism
A: addison’s
R: renal failure (AKI)
D: hypervitaminosis D
I: idiopathic (cats)
O: osteolytic disease
N: neoplasia (most common)
clinical signs of hypercalcemia
acute onset:
1. profound PU/PD
2. systemic illness (lethargy, anorexia)
3. vomiting
4. AKI - azotemia
treatment of hypercalcemia
indicated when iCa > 1.8 mmol/L or if concurrent azotemia
- IV 0.9% saline
- furosemide
- +/- glucocorticoids
- treat underlying disease
role of 0.9% saline in hypercalcemia treatment
acidifying - aids in renal elimination of Ca
do NOT use LRS - want the acidifying effect of saline
role of furosemide in hypercalcemia treatment
loop diuretic - helps eliminate Ca in urine
role of glucocorticoids in hypercalcemia treatment
only used if severe hypercalcemia and increasing signs despite fluid and lasix therapy
avoid if not needed
