Quiz II Electrolytes Flashcards
Define electrolyte
ions capable of carrying an electric charge
name two cations in the body
sodium
calcium
name two anions in the body
chloride
bicarbonate
Most abundant extracellular cation
maintains osmotic pressure
low levels produce edema(swelling)
sodium
When blood volume is low what two hormones help to maintain it
renin - angiotensinogenase
ADH - antidiuretic hormone
low sodium levels and 3 causes
hyponatremia
vomiting
burns
renal problems
high sodium levels and 3 causes
hypernatremia
diabetes insipidus
prolonged diarrhea
profuse sweating
normal range for sodium
136-145 mm/L
Major intracellular cation
regulates activity of neuromuscular junction and
cardiac muscle contraction
potassium
Controls amount of potassium available in circulation
Dietary intake
low levels of potassium
hypokalemia
high levels of potassium
hyperkalemia
normal range for potassium
3.5-5.0 mM/L
Major extracellular anion
maintain osmotic pressure
keeps body hydrated
maintains electroneutrality
Chloride
salt loss during renal disease
diabetic ketoacidosis
prolonged vomiting
causes of hypochloremia
dehydration
acute renal failure
prolonged diarrhea w/ loss of bicarbonate
aspirin intoxication
causes of hyperchloremia
normal range for chloride
90-109 mM/L
Second most abundant anion in extracellular fluid
bicarbonate
metabolic acidosis
renal failure
diarrhea
decreased levels of bicarbonate
respiratory acidosis
matobolic alkalosis after severe vomiting
hypokalemia
excess alkali intake
increased levels of bicarbonate
3 methods of analysis for bicarbonate
ion specific electrode
spectrophotometric method
enzymatic method
normal range for bicarbonate
22-28 mM/L
Second most abundant intracellular cation
magnesium
Most important application for testing magnesiums levels in blood
hypomagnesemia
can result in tetany
hemolyzed specimens are rejected
Normal range fo rmagnesium
1.5-2.5 mEq/L
required for blood coagulation
important in muscle contraction and
membrane permeability
Calcium
Two fractions of calcium
free; 60% of total calcium
protein bound
PTH - parathyroid hormone
calcitonin
antagonistic relationship
Regulate calcium
Required for intestinal absorption of calcium
Vitamin D
physiological active form of calcium
ionized calcium
vitamin d deficiency
liver disease
causes of hypocalcemia
vitamin d excess
multiple myeloma
causes of hypercalcemia
normal range for calcium
8.5-10.5 mg%
Major intracellular cation
levels inside rbc is 50 greater than in extracellular fluid
Phosphorus
Phosphate in the serum is combined with ammonium molybdate to form phosphomolybdate. Phosphomolybdate is then reduced to molybdenum blue which is measured with spectrophotometry
Fiske and Subbarrow Method
normal range for phosphorus
2.8-4.0 mg%
concentration of iron in the plasma represents what % or total body iron?
0.1%
found in oxyhemoglobin and reduced to hemoglobin
Ferrous, or iron II
stored in ferritin and hemosiderin and is the form that attaches to transferring
ferric, or iron III
TIBC is used to estimate what in the serum
transferrin levels
Reacts with the chromagen to produce detectable color in iron methods
ferrous
How is % iron saturation determined?
% saturation= serum Fe/TIBC x 100
Normal range for iron
m 60-150 ug/dL
f 50-130 ug/dL
Normal range for TIBC
250-450 ug/dL
Normal range for % iron saturation
20-50%
Formulas for anion gap and their ranges
NA - (Cl + HCO3) = 8-18 mmol/L
(Na+K) - (Cl+HCO3)= 12-20 mmol/L
uremia
lactic acidosis
severe dehydration
increase anion gap
instrument error
multiple myeloma
hypoalbuminemia
decrease anion gap
If after repeat testing anion gap stays the dame what else can be checked as indicator of possible uremia or ketoacidosis
BUN and glucose; elevated is indicative of either
compare to pt history and delta check
