Electrolytes

Question 1

What are signs and symptoms of fluid overload?

Answer 1

Bounding pulse, tachycardia, weight gain, hypertension, rales, cough, shortness of breath, dilute urine, jugular vein distention, edema,

Question 2

What are signs and symptoms of dehydration?

Answer 2

Decreased tear production, weight loss, hemoconcentration, skin tenting, hypotension, altered mental status, thready pulse, decreased urine production, dark concentrated urine, tachycardia, dry sticky mucus membranes,

Question 3

Controls water distribution. Regulated by hypothalamus. Decrease or increase is accompanied by a decrease or increase in water.

Answer 3

Sodium (Na+)
136-145 mEq/L
Antidiuretic hormone, thirst, renin-angiotensin-aldosterone system

Question 4

Hyponatremia?

Answer 4

Actual low levels of Na or a decrease in the amount of Na in relation to the amount of water: Fluid imbalance: over hydration. GI disturbance, diuretics.
For increased water, restrict fluids. Na loss, give Na. Malnutrition, improve nutrition. Tolvaptan: PO used to treat clinically significant hypervolemia and euvolemia hypernatremia.

Question 5

Hypernatremia?

Answer 5

Occurs when water losses exceed NA losses or when water intake is low. Fluid imbalance: dehydration. Causes include excessive water losses and increased NA intake.
For decreased water, fluid replacement. For increased NA, diet, salt free solutions. Hypotonic IV.

Question 6

Important in neuromuscular, skeletal and cardiac muscle function. Regulation requires adequate kidneys function. Major cation of ICF, 98% stored in ICF, 2% in ECF.

Answer 6

Potassium (K+), 3.5-5 mEq/L. Controls ICF osmotic pressure, regulates acid-base balance, mains neuro/muscular function vi the Na/K pump. Regulated by kidneys, aldosterone, Na/K pump.

Question 7

Causes of hypokalemia?

Answer 7

Diuretic therapy, GI loss, infusions of K-free fluids, decreased ingestion of K, diuretics, aldosteronism, renal disease, CHF, diet, anorexia, bulimia, laxative misuse

Question 8

Causes of hyperkalemia?

Answer 8

Renal failure, increased ingestion of K, misuse of supplements, extensive tissue injury, crushing injuries/burns, Excessive K in IV fluids, Addison’s disease, MI, hemorrhage/shock.

Question 9

Undesired effect that occurs when the med is administered

Answer 9

Side effect
May be anticipated by the HCP. Can be minor or serious. Resolve on their own with time.

Question 10

Unintended pharmacologic effects that occur when a med is administered

Answer 10

Adverse effect
Unanticipated event. Requires interventions.

Question 11

The most common electrolyte added to IV fluid?

Answer 11

K+ replacement, e.g. potassium chloride/KCl
Can only be given IV or PO
Must be diluted. Cannot be given faster than 10 mEq per hour. Must use a pump, not drip.

Question 12

Second most abundant cation in the body. Absorbed in the small intestine. Important for neuromuscular and cardiovascular functioning. Facilitates the transport of Na and K across the cell membrane.

Answer 12

Magnesium (Mg++), 1.3-2.1 mEq/L. Magnesium sulfate to fix issues with it. Conserved by kidney during times of inadequate in take, excreted in times of excessive intake. Helps keep K+ levels elevated. Influences Ca through effect on parathyroid gland.

Question 13

Causes of hypomagnesemia?

Answer 13

Impaired absorption, chronic alcohol abuse, GI tract loss, too rapid excretion through kidneys, decreased ingestion of Mg++. Diuretics, laxatives. Diabetic acidosis, renal failure, sepsis, burns.

Question 14

Causes of hypermagnesemia?

Answer 14

Renal failure, increased ingestion of Mg++, excessive use of Mg containing antacids, ingestion of cathartics (Epsom salts, MOM), hyperalimentation (TPN). Continuous infusions used to treat preeclampsia, pregnancy induced HTN, pre-term labor. Untreated DKA, Addison’s.

Question 15

Important for neuromuscular activity and blood clotting. Serum levels controlled by the parathyroid glands. Major ECF cation. Inverse or reciprocal relationship with phosphorous.

Answer 15

Calcium (Ca++). 9-10.5 mg/dL serum, 4.5-5.6 ionized. Majority is found in the bones and teeth, small percent found in the serum. Concentration kept constant by a Ca pump that constantly moves it in and out of cells.
In serum: 45% is bound to protein (mostly albumin), 40% is ionized, 15% is bound to other substances such as phosphate, citrate, carbonate.

Question 16

Causes of hypocalcemia?

Answer 16

Damage to parathyroid, hypoparathyroidism, diarrhea, diuretics, alcoholism, hyperphosphatemia, decreased absorption from intestines, low levels of vit D, inadequate Ca intake, hypomagnesemia, alkalosis, citrate

Question 17

Causes of hypercalcemia?

Answer 17

Primary hyperparathyroidism, prolonged immobilization, renal failure, steroids, hypophosphatemia, multiple myeloma/metastatic cancer, squamous cell carcinoma of lung and breast. Vit D overdose, overuse of aluminum hydroxide gel, Paget’s disease, acidosis.

Question 18

Anion in ICF. Absorbed in Gi tract, excreted through kidneys. Inverse relationship with Ca. Parathyroid gland controls hormonal regulation. Provides structural support to the bones and teeth.

Answer 18

Phsphorous (PO4), 2.5-4.5 mg/dL. 85% in bones and teeth combined in 1:2 ratio with Ca. 14% in soft tissues, 1% in ECF.
Parathyroid hormone acts on the kidneys to excrete excess phosphorous.

Question 19

Causes of hypophosphatemia? Treatment?

Answer 19

Hypercalcemia, decreased intake, decreased intestinal absorption, increased loss through the kidneys, shift of PH form ECF to ICF, hyperparathyroidism, diuretics
Treated with diet, replacement, underlying cause

Question 20

Causes of hyperphosphatemia?

Answer 20

Causes few symptoms itself but the resulting hypocalcemia can be life threatening. Usually reflects renal failure, increased intake. Hypoparathyroidism, less PTH so less excretion of phosphorous. Shift from the ICF to ECF.

Question 21

General care of electrolyte disorders?

Answer 21

Monitor labs, vitals, cardiac, I+O, weight. Administer meds properly. Must educate on meds, diet, follow up with HCP, SS report to HCP

Question 22

Major ECF cation, the ECF level makes up 99% of the body’s level. ICF only 1%. Responsible for water balance and determination of plasma osmolarity. Movement of chloride is closely associated with this.

Answer 22

Na, 136-145 mEg/L. Controlled and influenced by aldosterone, ADH, osmolality/osmolarity (blood 285-298 most/kg), renal mechanism.
Functions relate to acid-base balance, controlling neuromuscular function via the Na/K pump.

Question 23

Causes of hyponatremia?

Answer 23

Water intoxication. Dilutional hyponatremia: hypervolemia, CHF, renal failure. Homronal changes: SIADH, Addison’s disease, hypothyroidism. True hyponatremia.

Question 24

S/s of hyponatremia?

Answer 24

CNS changes: headache, irritability, confusion, personality changes, apprehension. Weight gain or weight loss. Tachycardia. May have edema. Hypotension or hypertension. GI: nausea, vomiting, ab discomfort, diarrhea.
Severe (115 or less): muscle twitching and tremors, focal weakness, seizures, signs of ICP, coma.

Question 25

Nursing responsibilities for hypernatremia and hyponatremia?

Answer 25

Maintain accurate I+O. weight pt, VS, regulate IV fluids, be alert to CNS changes, monitor labs/electrolytes, educate pt and family

Question 26

S/s of hypernatremia?

Answer 26

Personality changes, agitation, confusion, hallucinations, decreased LOC. S/s associated with dehydration: thirst (early), dry sticky mucous membranes, fleshed skin, oliguria, tachycardia, postural hyportension, fever. Muscle weakness and twitching, cramps.

Question 27

Sources of Na dietary, hidden, and OTC meds?

Answer 27

Diet: table salt, cheese, eggs, ham, smoked or pickled meats. Hidden: processed foods, canned foods, condiments, seasonings (MSG), baking products (baking powder/soda). OTC: cold products, cough syrups, antacids, alka-seltzer

Question 28

Explain K’s role in acid-base balance?

Answer 28

H+ and K+ ions shift back and forth between the ICF and ECF to maintain the pH. H+ ions move into the cells in acidotic states to help correct the low pH and K+ ions move out to maintain an electrically stable state. When the acidosis is corrected they switch back. Reverse happens in alkalosis.

Question 29

Explain ECF K+’s role in neuromuscular function?

Answer 29

Responsible for maintain action potentials in excitable cells of muscles, neurons, and other tissues (via Na-K pump). Assists in controlling cardiac rate and rhythm, Conduction of nerve impulses. Skeletal muscle contraction. Function of smooth muscles and endocrine tissues.

Question 30

Explain ICF K+’s role in neuromuscular function?

Answer 30

Role in intracellular metabolism and functions in the regulation of glycogen and protein synthesis. Primary ICF ion so has some control over the intracellular osmolarity and volume via the Na/K pump.

Question 31

S/s of hyperkalemia?

Answer 31

Skeletal muscle weakness progressing to flaccid paralysis, increased bowel motility, diarrhea, nausea, intestinal colic. Cardiac dysr, EKG changes, ventricular fibrillation/asystole. Death.

Question 32

EKG changes in hyperkalemia?

Answer 32

tall, tented T waves, wide QRS, prolonged PR interval, flat or absent P wave, ST segment depression

Question 33

Treatment of hyperkalemia?

Answer 33

Correct the cause. Limit PO intake of K and K containing meds. Take K out of IV fluids. IV glucose and insulin, correction of acidosis, CA salts (protection), dialysis, diet, cardiac monitoring, I+O. Pt education
Sodium polystyrene sulfonate (Kayexalate) enema or PO.

Question 34

S/s of hypokalemia?

Answer 34

Muscle weakness, decreased reflexes. GI: n/v, anorexia, constipation, ab distention, flatulence progressing to paralytic ileus. EKG changes, cardiac dysr, death

Question 35

EKG changes in hypokalemia?

Answer 35

Flat or inverted T wave, presence of a U wave, ST segment depression, peaked P wave, tachyarrythmias, PVCs, ventricular fibrillation/ventricular tachycardia

Question 36

Treatment of hypokalemia?

Answer 36

Correct the cause, oral K supplements, parental administration, cardiac monitoring, diet, KCL.
Rule: 10 mEq/hr. Max is 40 mEq over 4 hrs. Cannot be given SQ, IM, IV push. Should check renal function first.

Question 37

Dietary sources of K+?

Answer 37

Bananas, oranges, cantaloup, raisins, apricots, avocados, beans, potatoes, tomatoes, spinach, beef. Avoid black licorice, when eaten in large quantities can cause hypokalemia.

Question 38

Nursing interventions for K+?

Answer 38

Assess and monitor, VS, EKG, labs, I+O, K replacements. Provide safe environment. Digitalis toxicity, pt teaching for s/s of imbalance

Question 39

Functions of calcium?

Answer 39

Enzyme activation (blood clotting), skeletal and heart muscle activation, excitation, contraction, relaxation. Nerve impulse transmission, maintains membrane permeability by holding body cells together, firmness and rigidity to bones and teeth, assists in regulation of acid/base balance.

Question 40

Ca regulation? Calcitrol and calcitonin?

Answer 40

PTH raises the plasma Ca level by promoting the transfer of C from the bone to the plasma.
Cacitrol: most active form of vit D. Makes Ca and phosphate available for new bone formation. Promotes Ca absorption from duodenum.
Calcitonin: Ca lowering hormone produced by thyroid glands. Acts against PTH by transferring Ca from the plasma to the bone

Question 41

Intake of Ca needed?

Answer 41

Adults should consume at least 1000-1200 mg per day. Upper limits is 2.5 gm per day. Foods high in Ca are milk, yogurt, cheese, Ca-fortified OJ, ice cream, canned salmon, sardines, broccoli, tofu, rhubarb, spinach, almonds, figs, turnip greens

Question 42

S/s of hypocalcemia?

Answer 42

Paresthesia of nose, ears, fingertips, toes, circumoral region. Cardiac irregularities, tetany, seizures, trousseau’s and chvostek’s signs. Bleeding, petechiae, GI- increased peristalsis, osteoporosis.

Question 43

Treatment of hypocalcemia?

Answer 43

Diet therapy, PO Ca, vit D supplements, IV Ca, correct problem, hydration, check phosphorus level, cardiac monitoring

Question 44

Nursing responsibilities for hypocalcemia?

Answer 44

Observe for changes in neuromuscular irritability, seizure precautions, decrease stimulation, administer digitalis preps with caution, laryngeal and ab muscles particularly prone to spasms.
For severe deficit, have trach tray ready. Also after thyroid surgery, not only for possible laryngeal spasms but also neck swelling.

Question 45

S/s of hypercalcemia?

Answer 45

Muscle weakness, kidney stones, cardiac dysthymia, lethargy leading to coma, anorexia, n/v, dehydration, constipation, renal stones, pathological bone fractures.

Question 46

Treatment of hypercalcemia?

Answer 46

Definitive treatment: remove the cause. Hydrate with NS, oral phosphate. Mithracin, Aredia, Calcitonin (synthetic).
Encourage mobility whenever possible, strain urine if kidney stones are suspected, observe for CNS and musculoskeletal changes, I+O, assess VS, s/s, labs, monitor.

Question 47

Functions of magnesium?

Answer 47

Activates many enzyme strains, has sedative effect on CNS, transmits electrical impulses across nerves and muscles, skeletal muscle relaxation following contraction. Decreases or blocks the release of acetylcholine thereby acting as a smooth muscle relaxant. Aids in converting ATP to ADP for energy release.

Question 48

S/s of hypomagnesemia?

Answer 48

Neuromuscular irritability, hallucinations, agitation, personality changes, hypotension, positive Chvostek sign. Ventricular irritability: vtach, vfib, torsades de pointe

Question 49

Treatment for hypomagnesemia?

Answer 49

IM or IV magnesium sulfate. IV rate not to exceed 150 mg/min. Renal dose in renal insufficiency. While infusing watch for s/s of hypermag, respiratory depression, heart block. Calcium gluconate is antagonist.

Question 50

S/s of hypermagnesemia?

Answer 50

Diminished reflexes, respiratory depression, hypotension, flushed, feeling of warmth, sweating, bradycardia, drowsiness.

Question 51

Treatment for hypermagnesemia?

Answer 51

Calcium gluconate, stop administering any magnesium, hydration, dialysis

Question 52

Dietary sources of Mg?

Answer 52

Green leafy vegetables, nuts, legumes, seafood, whole grains, bananas, oranges, cocoa, chocolate. Daily requirement is 800-1200 mg.

Question 53

What is phosphorus needed for?

Answer 53

Cell membrane integrity, muscle function, neurologic function. Carb, protein, and fat metabolism. Buffering of acids and bases. ADP, ATP. Primary ingredient in 2,3-DPG.

Question 54

S/s of hypophosphatemia?

Answer 54

Muscle weakness, malaise, anorexia, irritability, apprehension, confusion, paresthesia, seizures, coma (late). Hypotension, myalgia, rhabdomyolysis, respiratory failure from weakened respiratory muscles. Decrease in O2 delivery to the tissues. Also effects platelet and WBC function.

Question 55

Foods high in phosphorous?

Answer 55

Cheese, dried beans, eggs, fish, milk and dairy, nuts, seeds, organ meats, poultry, whole grains.

Question 56

S/s of hyperphosphatemia?

Answer 56

Paresthesia, muscle spasms, cramps, pain, weakness, decreased mental status, seizures, tetany. Hyperreflexia: positive Chvostek and Trousseau signs. EKG changes, anorexia, n/v, calcification, tachycardia, ss of hypocalcemia

Question 57

Treatment of hyperphosphatemia?

Answer 57

Treat cause. Low PO diet, eliminate PO baed laxatives and enemas. Drugs to decrease absorption from the GI system. Aluminum, magnesium, or calcium gel or phosphate binding antacids (with meals). IV fluids, saline. Dialysis. Replace Ca

Question 58

How common are the Chvostek and Trousseau signs for hypocalcemia?

Answer 58

Chvostek’s sign is neither sensitive nor specific for hypocalcemia, since it is absent in about one third of patients with hypocalcemia and is present in approximately 10% of persons with normal calcium levels. Trousseau’s sign, however, is more sensitive and specific; it is present in 94% of patients with hypocalcemia and in only 1% of persons with normal calcium levels.

Question 59

Chvostek and Trousseau signs?

Answer 59

Chvostek’s sign is de- scribed as the twitching of facial muscles in response to tapping over the area of the facial nerve. Trousseau’s sign is carpopedal spasm that results from ischemia, such as that induced by pressure applied to the upper arm from an inflated BP cuff.

Question 60

What percentage/in L of an adult’s body weight is intracellular fluid, on average? Extracellular?

Answer 60

On average, Intra is 40%, or 28L. Extra is 20%, or 14L.

Question 61

How much of extracellular fluid is interstitial vs. plasma?

Answer 61

Interstitial is about 75% of extracellular fluid, plasma is 25%.

5% of the body’s total fluid volume is plasma.

Question 62

Explain changes in body fluid amount with age?

Answer 62

Compared to adults, infants have more stored in interstitial. About 80% of body weight of neonate is water, 90% for premature. Decreases with age and levels out at puberty. 15% of young adult’s weight is interstitial, which decreases with age. In typical adult male, 60% is water. Skeletal muscle mass declines, fat increases. After age 60, water content is about 45%.

Question 63

What solutes use ATP and active transport to move across membranes, in and out of cells?

Answer 63

Sodium-potassium pump
Calcium, hydrogen ions, amino acids, certain sugars