Calcium - Electrolytes Flashcards
what is the normal calcium range?
8.4 - 11.0
what is the function of calcium?
99% stored in bones (bones & teeth)
- bones
- blood
- beats (Heart)
what is calcium bound to?
to proteins (less than 50%)
where is calcium ionized?
found in serum (50% of calcium and is most important)
what is complexed calcium?
combined with nonprotein anions: phosphate, citrate, and carbonate
what is ionized calcium? and its purpose? 5
- Activate body chemical rxn
- Muscle contractions and relaxation
- Promote transmission of nerve impulse
- Cardiac contractility & automaticity
- Formation of prothrombin
what is one calcium regulator?
- Parathyroid Hormone (PTH) “pulls” *
1. Releases Ca from the bone
2. Increases Ca absorption from GI
3. Increases Ca absorption from renal tubules
what is the second calcium regulator?
- Calcitonin – secreted by thyroid “keeps” *
1. Antagonist of PTH
2. Secretion stimulated by high serum Ca++
3. Inhibits Ca reabsorption from bone
what are two other minor calcium regulators?
- Phosphate
Reciprocal relationship with Ca
(Ca = Phos) - Vitamin D
Necessary for absorption & utilization of Ca
what causes HYPOcalcemia? 6
- think “LOW CAL”*
1. Low parathyroid hormone
2. Oral intake inadequate
3. Wound drainage
4. Celiac’s, Crohn’s Disease, & Corticosteroids
5. Acute pancreatitis
6. Low Vitamin D levels
what are the signs and symptoms of HYPOcalcemia? 6
- think CRAMPS
1. Confusion
2. Reflexes hyperactive
3. Arrhythmias (prolonged QT interval)
4. Muscle spasms (calves/feet, tetany, seizures)
5. Positive Trousseau’s
6. Signs of Chvostek’s (facial nerves hyperexcitable)
CATS of hypocalcemia?
Convulsions
Arrythmias
Tetany (hand thing)
Spasms and stridor
what is a positive trousseau’s?
Carpopedal spasm of hand when
- Blood supply
- Pressure on nerve
Occurs several minutes after BP cuff inflated > systolic BP
what is a positive chvostek’s ?
- Spasm of muscles innervated by facial nerve
- Tap facial nerve anterior to ear lobe below zygomatic process
how can HYPOcalcemia affect the heart?
- prolong QT interval
- Prolong ST segment
- cardiac contractility
- sensitivity to digoxin
HYPOcalcemia lab data includes what? 5
- Serum calcium levels < 8.4 mg/dl
- Albumin/protein levels can give incorrect levels of Ca
- Ionized (serum) levels of Ca should be obtained for accurate results
- PTH levels can effect Ca
- Magnesium and phosphorus levels should also be obtained
Medical treatment of HYPOcalcemia?
Acute symptomatic 🡫 Ca is emergency =
Requires prompt adm. of IV Calcium
*10% Ca-Gluconate
For severe symptoms
*Ca-Chloride
Never give IM
*Oral Ca or Vitamin D
Nursing interventions for HYPOcalcemia?
- Identify pt at risk
- Seizure precautions if severe Ca
- Monitor airway
- Monitor ECG
- Educate pt: Ca loss & risks & Ca rich foods
What can cause HYPERcalcemia? 7
*think “HIGH CAL”
1. Hyperparathyroidism
2. Increased intake of calcium
3. Glucocorticoids usage
4. Hyperthyroidism
5. Calcium excretion < w/Thiazide diuretics & renal failure, bone ca
6. Adrenal insufficiency (Addison’s)
7. Lithium usage (affects parathyroid)
HYPERcalcemia signs and symptoms? 4
*think “WEAK”
1.Weakness of muscles
2. EKG changes-(shortened QT interval & prolonged PR interval)
3. Absent reflexes, “a”bsent minded (disoriented), “a”bdominal distention from constipation
4. Kidney stone formation
how can HYPERcalcemia affect the heart? 4
- Calcium: inotropic effect on heart & reduces heart rate
- Shorten ST segment & QT interval
- Prolonged PR interval
- Potentiate digoxin toxicity
HYPERcalcemia lab data? 5
- Serum calcium > 11.0 mg/dl
- ECG-dysrhthmias
- PTH- increased
- X-ray-reveal osteoporosis
- Urine
Medical treatment for HYPERcalcemia? 7
1.Treat underlying cause
2. Dilute serum Ca++ with NS
3. Lasix/furosemide
4. IV phosphate
5. Calcitonin
6. Glucocorticoids
7. Hemodialysis or CAPD
nursing interventions for HYPERcalcemia? 7
- Monitor for pt risk
- activity & fluids if possible
- ↓ Ca++ intake
- Safety measures for confusion
- Monitor ECG, I&O, breath sounds
- Monitor for Digoxin toxicity
- Prevent Ca++ renal stones
