2.1.1 CV: First increases HR and BP; Severe hypercalcemia depresses HR; dysrhythmias; increased and unnecessary
clot formation, shown by s/s of impaired blood flow to tissues (cap refills, temperature inequality, color changes).
2.1.2 NM: Severe muscle weakness, decreased deep tendon reflexes, altered LOC, psychiatric problems.
2.3.3 Assess for slowed
or impaired blood
flow (calf circ, cap
changes), esp. in
BLE, pelvic region.
2.3.4 Monitor frequently for s/s of
effective treatment or worsening
2.4 Serum Value >10.5 mg/dL
2.5.1 Actual Excess: increase in total body Ca++.
18.104.22.168 Ex: Excess
intake of Ca++
or Vit D, Kidney
failure, use of
2.5.2 Relative Excess: total body
Ca++ is normal, serum Ca++
22.214.171.124 Ex: Hyperparathyroidism;
malignancies (esp of lung,
breast, and bone); indirect
immobility; use of
3 Normal Range (Free/Unbound Ca++ in blood): 9.0-10.5 mg/dL
3.1 Any change in Ca++ can have major effects on
function because of the relatively low serum levels
4 Importance in the Body
4.1 Functions are closely r/t P and Mg
4.2 Enters the body through dietary intake (esp. dairy!) and
absorption is facilitated by Vit D.
4.2.1 Dairy products, tofu, leafy greens, and almonds are high in calcium.
4.3 Absorbed in the intestinal tract, stored in the bones, and regulated
by PTH (parathyroid hormone) and TCT (thyrocalcitonin).
4.3.1 PTH increases serum levels by releasing free Ca++ from bone
storage, stimulating Vit D activation to increase intestinal
absorption, inhibiting kidney excretion and stimulating kidney
reabsorption of Ca++.
4.3.2 PTH is inhibited when Ca++ is high in the blood, and TCT is
excreted by the thyroid. TCT inhibits bone resorption, inhibits
Vit D assisted intestinal uptake, and increases the kidney
excretion of Ca++.
4.4 Excitable membrane stabilizer, regulates the depolarization
and generation of AP's in the CNS and PNS.
4.4.1 Low serum levels make excitable
membranes MORE excitable because
they increase the movement of Na+
across the membranes.
4.4.2 High serum levels make excitable membranes LESS
excitable, requiring MORE stimuli.Usually this affects
the heart, skeletal muscles, and intestinal smooth
muscles initially and predominantly, but affects all systems.
4.4.3 Maintains bone strength,
skeletal and cardiac muscle
4.4.4 Controls impulse
transmission in the
CNS and PNS.
4.4.5 Remember Ca++
channels from Phys?
4.5 Utilized by many
involved in blood
5 Ignaviticus, D., & Workman, M. L. (2013). Medical-surgical nursing: Patient-centered collaborative
care. (7th ed., pp. 187-191). St. Louis, Missouri: Elsevier-Saunders.