Electrolyte Imbalances

Question 1

Why do patients with chronic renal failure—and thus chronically elevated potassium levels—have relatively mild symptoms of this electrolyte imbalance that would be disabling in other individuals.

Answer 1

K+ adaption- increased aldosterone levels increases secretion of of K+ via colon and shifts K+ ions from extracellular fluid into cells to normalize RMP

Question 2

Hyperkalemia

Answer 2

causes muscle dysfunction d/t hypopolarization of smooth and skeletal muscle. S/Sx muscle weakness, cardiac dysrhythmias. RMP lies above threshold. Once they’ve discharged they can’t contract again.

Question 3

Hypokalemia

Answer 3

Muscle cells are hyperpolarized and less reactive to stimuli. S/Sx abd distention, paralytic ileus, muscle weakness, postural hypotension, flaccid paralysis, ectopic beats, rhabdo, neuropathy

Question 4

Hypercalcemia

Answer 4

decreased neuromuscular activity, muscle weakness, fatigue, polyuria, nausea, anorexia, diminished reflexes, lethargy, cardiac dysrhythmia

Question 5

Hypocalcemia

Answer 5

increased neuromuscular excitability, +trosseau, + chvostek, twitching, cramping

Question 6

Hyperphosphatemia

Answer 6

typically causes hypocalcemia. Increased neuromuscular excitability. Deposition of calcium phosphate salts in the tissues l/t aching, stiff joints, itching, conjunctivitis

Question 7

Hypophosphatemia

Answer 7

decrease in ATP and thereby cellular function. S/sx anorexia, muscle weakness, seizures, hemolysis, confusion, cardiac dysrhythmias

Question 8

Hypermagnesimia

Answer 8

neuromuscular depression, decreased DTRs, lethargy, hypotension, diaphoresis, bradycardia, respiratory depression

Question 9

Hypomagnesimia

Answer 9

can be caused by chronic EtOH or hypocalcemia. Increased neuromuscular excitability, insomnia, hyperactive reflexes, muscle cramps, twitching, grimacing, +Chvostek, dysphagia, tetany, ataxia

Question 10

Hypernatremia

Answer 10

thirst, oliguria, confusion, lethargy, coma, seizures

Question 11

Hyponatremia

Answer 11

nonspecific manifestations of CNS dysfunction. Malaise, anorexia, nausea, vomiting, confusion, lethargy, cerebral herniation

Question 12

ADH

Answer 12

synthesized in hypothalamus, released from posterior pituitary. Released when blood is overly concentrated and causes the reabsorption of water and decrease in UOP.

Question 13

Aldosterone

Answer 13

synthesized and secreted by adrenal cortex. Stimulate by release of angiotensin II. Causes renal tubules to reabsorb saline (Water and salt) to expand extracellular volume.

Question 14

ECV (extracellular fluid volume)

Answer 14

abnormalities in the amount of total body fluid

Question 15

Body fluid concentration (Water imbalances)

Answer 15

abnormalities in the concentration of total body fluid

Question 16

ECV excess causes

Answer 16

IVF, hyperaldosteronism, CHF, cirrhosis, ESRD, Cushing, corticosteriod therapy

Question 17

Electrolyte Distribution

Answer 17

concentrations of K+, Mg+, and Phos are higher inside cells. Bones and cells are electrolyte pools. Largely effected by insulin, PTH, and epinephrine.

Question 18

Electrolyte excretion

Answer 18

occurs through urine, feces, and sweat. Effected by kidney function, GFR, drugs.