Calcium Flashcards
Calcium- Functions
major cation in bone and teeth blood clotting transmission of nerve impulse myocardial contractions muscle contractions
how the body regulates calcium
source of calcium= diet
how the body regulates calcium- calcium absorption requires
active form of vitamin D (diet or sunlight)
how the body regulates calcium- PTH
maintain normal serum Ca level by regulating the movement of Ca into/out of bone
Ca readily available supply b/c bone
production and release are stimulated by low serum Ca level
inc bone resorption (movement of Ca out of bone)
inc GI absorption of Ca
inc renal tubule reabsorption of Ca
vit B12 absorption and use
Ca and P have inverse relationship
how the body regulates calcium- to inc Ca: PTH secretion
bone
intestine
kidneys
how the body regulates calcium- to dec Ca: Calcitonin
bone intestine kidneys produced by thyroid gland stimulated by high serum Ca level Opposes action of PTH and lowers the Ca level by dec GI absorption, inc Ca deposition into bone, promoting renal excretion
how the body regulates calcium- Vitamin D facilitates Ca absorption
Dietary intake
sunlight
Calcium info
1% in serum
ionized ca- free ca (most active form)
bound to protein (albumin)
complexed bound to other anions
Calcium info: NM activity
inc calcium stabilizes excitable membranes (Ca calms)
Calcium info: blood clotting
ca clot (CC) inc ca causes excessive clotting dec calcium (DC)- low Ca doesnt clot(bleeding)
Calcium info: teeth and bone formation
98% of it found in bone
osteoporosis-> fx
Calcium info: changes in serum pH
alter the level of ionized Ca without altering the total Ca level
a dec plasma pH (acidosis) de Ca binding to albumin (more ionized Ca)
inc plasma pH (alkalosis) inc Ca binding leading to dec ionized Ca
alteration in serum albumin levels affect total Ca level
Low albumin levels = drop in total Ca level (BUT the level of ionized Ca is not affected)
Calcium: Pt at risk- Labs
8.6-10.62 mg/dL
Hypercalcemia: Pt at risk-
high serum ca
excitability of muscles and nerves- need stronger stimulus
2/3 caused by hyperthyroidism
1/3 caused by malignancy from myeloma and breast, lung, and kidney cancer (through bone destruction from tumor invasion, or tumor secretion of a parathyroid related protein), which stimulates Ca release from bone
Hypercalcemia: Pt at risk- prolonged immobilization
bone mineral loss and inc plasma Ca concentration
Hypercalcemia: Pt at risk- rare case
vit D overdose/ inc Ca intake
Hypercalcemia: Pt at risk- etc
excess Ca- excitability of both muscles and nerves hyperparathyroidism malignancy prolonged immobility RF multiple bon Fx thiazide diuretics- inc action of PTH overuse of Ca containing meds Steroids- mobilize Ca from bone Vit D/Ca overdose
Hypercalcemia: Assessment- dec NM excitability
muscle weakness
incoordination
fatigue
Hypercalcemia: Assessment: dec peristalsis
dec peristalsis
Hypercalcemia: Assessment: Neuro
lethargy, confusion
depressed reflexes
Hypercalcemia: Assessment: flank pain
may indicate renal calculi
Hypercalcemia: Assessment: dec (Faster) blood clotting time (easy blood clotting)
esp lower extremities
risk of DVT
Hypercalcemia: Assessment: cardiac
dysrhythmias
monitor: HR,BP, O2stats, pallor, EKG charges, DVT, assess blood flow in LE, LE temp
Hypercalcemia: Assessment: bone Fx
with Ca released from bone
Hypocalcemia: Pts at risk
inc nerve excitability
can be caused by any condition that dec the production of PTH
surgical removal of parathyroids
Hypocalcemia: Pts at risk- meds
in loss of ca= hypocalcemia
loop diuretics (lasix- furosemide)
laxative abuse
dec vit D
Hypocalcemia: Pts at risk- inc phosphorus
combines with Ca-> deposited in tissue
Dec Ca absorption in intestines
Hypocalcemia: Pts at risk- pancreatitis
lipolysis produces fatty acids that combine with Ca ions dec serum Ca levels
Hypocalcemia: Pts at risk- multiple blood transfusion
b/c citrate used to anticoagulate the blood binds with the Ca
Hypocalcemia: Pts at risk- dec serum albumin levels
will dec total Ca
ionized Ca not affected
Hypocalcemia: Pts at risk- burned or diseased tissue
traps Ca ions from ECF
Hypocalcemia: Pts at risk- high pH inc Ca binding to protein
dec amt of ionized Ca
Hypocalcemia- Assessment: Dec Ca
inc Na movement into cells
Hypocalcemia- Assessment: most common S&S
overstimulation of nerves and muscles
Hypocalcemia- Assessment: painful cramps
foot, leg, abdomen (diarrhea)
Hypocalcemia- Assessment: etc
tingling, numbness tetany Trousseau's sign chvostek's sign inc tendency to bleed (dec clotting) ECG changes, thread pulse high risk for bone Fx
Hypocalcemia- Assessment: labs
Mg, PTH, P, albumin
Hypercalcemia- Nsg Dx: risk for
activity intolerance- muscle weakness
electrolyte imbalance- excessive bone destruction
injury- NM and sensorium changes
Hypercalcemia- Nsg Dx: potential complications
dysrhythmias
Hypocalcemia- Nsg Dx: risk for
acute pain- sustained muscle contraction
ineffective breathing pattern- laryngospasm
electrolyte imbalance- dec production of PTH
injury- tetany and seizures
Hypocalcemia- Nsg Dx: potential complications
Fx, respiratory arrest
Hypercalcemia- Nursing goals
hydration and promote excretion
Hypercalcemia- Nursing goals: meds (IV/PO hydration)
IV/PO hydration (3000-4000mL daily PO): promotes excretion of Ca and dec kidney stone formation
Hypercalcemia- Nursing goals: meds (loop diuretics)
inc Ca excretion (basic treatment promoting urinary excretion of Ca and hydrating with isotonic saline infusions)
monitor: UOP, FVD
no thiazide diuretics: inhibits Ca excretion
avoid antacids- most have Ca
Calcitonin- given IM/subcut lowers serum Ca level; intranasal form not effective
Hypercalcemia- Nursing goals: mobilize pt
wt bearing activity
Hypercalcemia- Nursing goals: etc
dec dietary Ca intake
safety precaution with LOC
Hypocalcemia- Nursing goals: severe hypocalcemia
IV preparations of Ca are given
Hypocalcemia- Nursing goals: mild hypocalcemia
diet high in Ca rich foods along with Vit D supplementation
Hypocalcemia- Nursing goals: administer
supplements: PO 1-1.5 hrs after meal; IV may be necessary after thyroid surgery
dietary intake Ca with Vit D supplement
if inc P, administer phosphate binding antacids
Hypocalcemia- Nursing goals: monitor
bone fx with chronic low Ca chvotstek's and trousseau's sign Mg, PTH, Ca, albumin cardiac rhythm observe pt with thyroid or neck srugery
