Electrolytes Flashcards
what 8 things/processes are electrolytes an essential component of?
volume and osmotic regulation
myocardial rhythm
cofactor in enzyme activation
Regulation of ATP ion pumps
acid-base balance
blood coagulation
neuromuscular excitability
production of ATP from glucose
sodium is the major _______ _______. It determines the _______ of plasma, and it’s needed for ______ transport across the cell membrane.
sodium is the major extracellular cation. It determines the osmolality of plasma, and it’s needed for active transport across the cell membrane
regulation of sodium depends on what? What percent of sodium is reabsorbed?
regulation of sodium depends on intake and excretion of water
60 -75% of sodium reabsorbed. (Maintained by Cl- reabsorption or H+ secretion)
what are symptoms of hyponaturemia?
nausea, vomiting, muscle weakness, headache, lethargy, severe symptoms (seizures), coma, respiratory depression
what are three reasons for hyponatremia, and reasons for each of those?
- increased sodium loss
- decreased aldosterone
- diuretics
- ketonuria - increased water retention
- renal failure
- nephrotic syndrome
- hepatic syndrome
- CHF - water imbalance
- excess water intake
- pseudohyponaturemia
what are symptoms of hypernatremia
CNS, altered mental state, lethargy, irritation, restlessness, muscle twitching, fever
what are three causes of hypernatremia
- excess water loss
- diabetes insipidus
- renal tubular disorder
- prolonged diarrhea
- severe burns - decreased water intake
- elderly and infants who cannot ask for water - increased intake or retention
- hyperaldosteronism
- sodium bicarb excess
- dialysis
what is the analysis method for sodium?
ion specific electrodes
what is the reference range for sodium?
136 - 145 mmol/L
Potassium is the major _______ _______. Why is there only 2% of the body’s K+ circulating in the plasma?
it’s the major intracellular cation
there’s only 2% because cellular functions require the body to maintain a low ECF concentration
what are four functions of potassium? How it is potassium regulated?
functions to regulate:
- neuromuscular excitability
- contraction of the heart
- intracellular volume
- H+ concentration
regulation:
- K+ absorbed, and then aldosterone causes K+ to be secreted into urine in exchange for Na+
hypokalemia symptoms and four general reasons for hypokalemia
symptoms: weakness, fatigue, constipation, (and paralysis)
reasons for hypokalemia
1. gastrointestinal loss
2. renal loss
3. cellular shift
4. dehydration
what are four reasons for gastrointestinal loss causing hypokalemia, and six reasons for renal loss causing hypokalemia?
GI loss:
1. vomiting/diarrhea
2. gastric suction
3. intestinal tumor
4. malabsorption’
Renal loss:
1. diuretics
2. nephritis
3. Cushing’s / hypoaldosteronism
4. hypomagnesemia
5. renal tubular acidosis
6. acute leukemia
what are two reasons for cellular shift as they relate to hypokalemia?
cellular shift:
- alkalosis
- insulin overdose
what are 4 symptoms of hyperkalemia? What are four general reasons for potassium decreases?
muscle weakness, tingling, numbness, and mental confusion
decreased renal excretion, cellular shift, increased intake, or artifact
what are three reasons for decreased renal excretion, cellular shift, and artifact as they relate to hyperkalemia?
decreased renal excretion:
1. acute or chronic renal failure
2. hypoaldosteronism
3. Addison’s disease (hypoadrenalcorticalism)
cellular shift:
1. acidosis
2. chemo
3. hemolysis
artifact:
1. sample hemolysis
2. thrombocytosis
3. prolonged tourniquet use during blood draw
what is the reference range for potassium?
3.5 - 5.1 mmol/L
Chloride is the major _______ ______. It maintains what three things?
it is the major extracellular anion/ It maintains osmolality, blood volume. and electroneutrality
After chloride is ingested and then absorbed in the intestine, anything left is reabsorbed where and with what? Excess chloride is excreted in what two places?
it’s reabsorbed in conjunction with sodium in the tubules
excess Cl- is excreted in the urine and sweat
what are five ways to have hypochloremia?
excessive loss from:
1. vomiting
2. diarrhea
3. diabetic ketoacidosis
4. aldosterone deficiency
5. pyelonephritis
what are two ways to have hyperchloremia?
excess loss of bicarbonate due to GI loss of metabolic acidosis
what is the reference range for chloride?
98 - 107 mmol/L
bicarbonate is the _____ most common ____ in the ____ fluid
bicarbonate is the second most common anion in the extracellular fluid
how does bicarb function is the major buffering component system in the blood?
bicarb diffuses out of the cell in exchange for chloride to maintain ionic charge neutrality within the cell
how is bicarbonate regulated?
bicarbonate reabsorbed in tubules as CO2. In alkalosis (relative increase in bicarbonate), the kidneys increase excretion of HCO3- into urine carrying along a cation
during compensation for acidosis, the body will reabsorb more than 90% of bicarbonate to make the blood more alkaline
what is the measurement system for measuring bicarbonate?
blood gas testing vie co-oximetry measurement of CO2
what is the reference range for bicarbonate
22 - 29 (22-33??) mmol/L
what two ways is calcium found in the blood?
it’s in the blood either
- free (active form)
- bound to a protein (albumin) or anion (bicarbonate)
(Ca2+ conc. more in blood than smooth muscle)
decreased ionized calcium impairs _____ function, so you have to maintain normal concentration during ____ and critically ill patients
impairs myocardial function
maintain normal Ca2+ levels during surgery
what three things regulate serum calcium
parathyroid hormone (PTH), vitamin D, and calcitonin
what three body parts play a role in calcium homeostasis?
the intestines, bones, and kidneys
what are two symptoms of hypocalcemia?
neuromuscular irritability and cardiac irregularities
what are five ways to develop hypocalcemia
- primary hypoparathyroidism
- vit D deficiency
- hypo/hypermagnesemia
- acute pancreatitis
- renal disease
what are 7 different symptoms of hypercalcemia?
- drowsiness
- weakness
- depression
- lethargy
- coma
- anorexia
- ulcers
what are four ways to develop hypercalcemia?
- primary hyperparathyroidism
- increased vit D
- malignancy
- multiple myeloma
magnesium is mostly found in what four places? 1% of it is found where?
mostly found in
1. bone
2. muscle
3. organ tissue
4. soft tissue
1% found in serum where 1/3 of it is bound to albumin
magnesium is a cofactor for what 8 enzyme functions?
- glycolysis
- transcellular ion transport
- neuromuscular transmission
4 - 7. carb, proteins, nucleic acids, lipid synthesis - release of/ response to certain hormones
Where and how is magnesium regulated?
Mg2+ controlled by the kidneys, which either reabsorb magnesium during deficiency (30% by proximal tubule) or excrete it in excess
Henle’s loop is major regulation site
What hormone is responsible for magnesium regulation, and how?
PTH increases in reabsorption of MG2+ and enhances absorption in the intestine
what four bodily states can be affected by hypomagnesemia?
cardiovascular, neuromuscular, psychiatric, and metabolic
what are 7 symptoms of hypomagnesemia?
- arrhythmias
- cramps
- seizures
- paralysis
- coma
- depression
- psychosis
what are four general ways to be magnesium deficient?
- increased excretion
- decreased absorption
- reduced intake (poor diet)
- other (chronic alcoholism)
what are specific ways increased excretion can result in hypomagnesemia?
renal: tubular disorders
endocrine: hyper-
- (para)thyroidism
- aldosteronism
- calcemia
and diabetic ketoacidosis
drug-induced: diuretics, antibiotics, cyclosporine
what are decreased absorption causes of hypomagnesemia?
surgical resection of small intestine, pancreatitis, vomiting/diarrhea, and laxative abuse
what are eight symptoms of hypermagnesemia
bradycardia, heart block, skin flushing, increased skin temp, nausea, vomiting lethargy, coma
what are three general reasons for hypermagnesemia?
decreased excretion, increased intake, and miscellaneous
what are four specific reasons for decreased exertion leading to hypermagnesemia
- acute/chronic renal failure
- hypothyroidism
- hypoaldosteronism
- decreased growth hormone
what three things cannot be used for magnesium analysis?
oxalate, citrate, and EDTA
Phosphate is found everywhere in living cells. Phosphate participates in most important biochemical processes such as ______, _____, and _____
DNA/RNA, enzymes, ATP
what four things regulate phosphate in the body?
- absorbed through diet, released from blood, or lost from bone
- PTH lowers phosphate blood concentration (by increasing renal excretion)
- via D increases phosphate in blood
- growth hormone
what are seven reasons for hypophosphatemia?
- diabetic ketoacidosis
- chronic obstructive pulmonary disease
- asthma
- malignancy
- inflammatory bowel disease
- anorexia nervosa
- alcoholism
six reasons for hyperphosphatemia
renal disease, increased intake, intense exercise, infections, neoplasm disorders, intravascular hemolysis
there is a ______ mortality rate associated with hypophosphatemia?
high
