Fluid and Electrolyte Imbalances (Fundamentals Ch 57)

Question 1

Electrolytes

Answer 1

• minerals present in all body fluids
• regulate fluid balance and hormone production
• strengthen skeletal structures
• act as catalysts in nerve response, muscle contraction, and metabolism of nutrients

Question 2

Fluid volume deficits (FVDs)

Answer 2

Isotonic FVD (hypovolemia)
Dehydration

Question 3

Isotonic FVD

Answer 3

• loss of water and electrolytes from the ECF

- referred to as hypovolemia because intravascular fluid is also lost

Question 4

Dehydration

Answer 4

• loss of water from body w/o loss of electrolytes

- this hemoconcentration results in increases in Hct, serum electrolytes, and urine specific gravity

Question 5

Compensatory mechanisms for FVD

Answer 5

• sympathetic nervous system response of:
  1) increased thirst
  2) antidiuretic hormone (ADH) release
  3) aldosterone release

Question 6

Are older adults at increased risk for dehydration?

Answer 6

Yes

-due to decreased total body mass

Question 7

Causes of isotonic FVD (hypovolemia)

Answer 7

1) abnormal GI losses–vomiting, ng suctioning, diarrhea
2) abnormal skin losses–diaphoresis
3) abnormal renal losses–diuretic therapy, diabetes insipidus, kidney disease, adrenal insufficiency
4) third spacing–peritonitis, intestinal obstruction, ascites, burns
5) hemorrhage
6) altered intake–impaired swallowing, confusion, NPO

Question 8

Causes of dehydration

Answer 8

1) hyperventilation
2) prolonged fever
3) diabetic ketodacidosis
4) enteral feeding w/o sufficient water intake

Question 9

Subjective and objective data of FVD

Answer 9

1) vital signs–hypothermia, tachycardia, thready pulse, hypotension, orthostatic hypotension, decreased central venous pressure, tachypnea, hypoxia
2) neuromusculoskeletal–dizziness, syncope, confusion, weakness, fatigue
3) GI–thirst, dry mucous membranes, dry furrowed tongue, N/V, anorexia, acute weight loss
4) renal–oliguria (decreased production of urine)
5) other clinical findings–diminished cap. refill, cool clammy skin, diaphoresis, sunken eyeballs, flattened neck veins, absence of tears, decreased skin turgor

Question 10

Lab findings associated with FVD

Answer 10

1) Hct–increased in both hypovolemia and dehydration (unless FVD is due to hemorrhage)
2) serum osmolarity–dehydration–increased hemoconcentration osmolarity (greater than 300 mOsm/kg)- increased protein, BUN, electrolytes, glucose
3) urine sp. gravity and osmolarity–increased concentration (urine sp. gravity > 1.030)
4) serum sodium–dehydration–increased hemoconcentratin

Question 11

Nursing care for FVD

Answer 11

1) assess respiratory rate, symmetry, effort
2) monitor SOB and dyspnea
3) check urinalysis, SaO2, CBC, electrolytes
4) administer supplemental O2 as prescribed
5) measure client’s weight daily at same time of day using same scale
6) observe for N&V
7) assess & monitor VS (check for hypotension & orthostatic hypotension)
8) check neurological status to determine LOC
9) assess heart rhythm (may be irregular, tachycardic)
10) initiate & maintain IV access
11) place client in shock position ( on back with legs elevated)
12) fluid replacement: administer IV fluids as prescribed (isotonic solutions–Lactated Ringer’s or 0.9% NaCl; blood transfusion)
13) monitor I&O–encourage as tolerated; notify provider of urine output less than 30 mL/hr
14) monitor LOC and ensure client safety
15) assess level of gait stability
16) encourage client to use call light for assistance
17) encourage client to change positions slowly
18) check cap refill
19) provide frequent oral care
20) prevent skin breakdown

Question 12

Fluid volume excess (FVE)

Answer 12

-isotonic retention of water and sodium in abnormally high proportions

Question 13

Overhydration

hypoosmolar fluid imbalance

Answer 13

• gain of more water than electrolytes

- hemodilution results in decreases in Hct, serum electrolytes, and protein

Question 14

Compensatory mechanisms for FVE

Answer 14

1) increased release of natriuretic peptides–result in increased excretion of sodium and water by kidneys
2) decreased release of aldosterone

Question 15

Causes of hypervolemia

Answer 15

1) chronic stimulus to kidneys to conserve Na and water (heart failure, cirrhosis, increased glucocorticosteroids)
2) abnormal kidney function w/ reduced excretion of Na and water (kidney failure)
3) interstitial to plasma fluid shifts (hypertonic fluids, burns)
4) age-related changes in CV and kidney function
5) excessive Na intake from IV fluids, diet, medications (Na bicarbonate antacids, hypertonic enema solutions)

Question 16

Causes of overhydration

Answer 16

1) water replacement w/o electrolyte replacement (strenuous exercises w/ diaphoresis)
2) SIADH–excess secretion of ADH
3) head injuries
4) barbiturates
5) anesthetics

Question 17

Subjective and objective data of FVE

Answer 17

1) VS–tachycardia, bounding pulse, hypertension, tachypnea, increased central venous pressure
2) neuromusculoskeletal–confusion, muscle weakness
3) GI–weight gain, ascites
4) respiratory–dyspnea, orthopnea, crackles
5) other clinical findings–edema, distended neck veins

Question 18

Lab findings associated w/ FVE

Answer 18

1) Hct–hypervolemia: decreased Hct; overhydration: decreased Hct = hemodilution
3) serum osmolarity–overyhdration: < 280 mOsm/kg
4) serum Na–hypervolemia: Na within expected range (136-145 mEq/L)
5) electrolytes, BUN, creatinine–hypervolemia&overhydration: decreased
6) ABGs–respiratory alkalosis (decreased PaCO2, increased pH)

Question 19

Nursing care for FVE

Answer 19

1) assess respiratory rate, symmetry, effort
2) assess breath sounds in all lung fields (may be diminished w/ crackles)
3) monitor for SOB and dyspnea
4) check ABGs, SaO2, CBC, CX-ray results (may indicated pulmonary congestion)
5) position client in semi-Fowler’s
6) measure client’s weight daily
7) monitor and document edema (pretibial, sacral, periorbital)
8) monitor I&O
9) implement prescribed fluid and Na intake restrictions
10) administer supplemental O2 as needed
11) reduce IV flow rates
12) administer diuretics as prescribed (osmotic, loop)
13) monitor and document circulation to extremities
14) reposition client at least q 2 hr
15) support arms and legs to decrease dependent edema as appropriate
5)

Question 20

Clients at greatest risk for electrolyte imbalances

Answer 20

1) infants and children
2) older adults
3) clients who have cognitive disorders
4) chronically ill clients

Question 21

Sodium (Na+)

Answer 21

• major electrolyte found in ECF
• present in most body fluids or secretions
• essential for maintenance of acid-base and fluid balance, active and passive transport mechanisms, and irritability and conduction of nerve and muscle tissue
• 136-145 mEq/L

Question 22

Hyponatremia

Answer 22

• serum Na+ level < 136 mEq/L
• a net gain of water or loss of sodium-rich foods
• delays and slows depolarization of membranes
• water moves from ECF to ICF, causes cells to swell (cerebral edema)

Question 23

Causes of hyponatremia

Answer 23

1) deficient ECF volume
2) abnormal GI losses–vomiting NG suctioning, diarrhea, tap water enemas
3) renal losses–diuretics, kidney disease, adrenal insufficiency, excessive sweating
4) skin losses–burns, wound drainage, GI obstruction, peripheral edema, ascites
5) increased or normal ECF volume–excessive oral water intake, SIADH
6) edematous states–heart failure, cirrhosis, nephrotic syndrome
7) excessive hypotonic IV fluids
8) inadequate Na+ intake (NPO status)
9) age-related risk factors–older adults greater risk due to incidences of chronic illnesses, use of diuretic medications, and risk for insufficient Na+ intake

Question 24

Subjective and objective data of hyponatremia

Answer 24

1) physical assessment findings–vary with a normal, decreased, or increased ECF volume
2) VS–hypothermia, tachycardia, rapid thready pulse, hypotension, orthostatic hypotension
3) neuromusculoskeletal–headache, confusion, lethargy, muscle weakness w/ possible respiratory compromise, fatigue, decreased deep tendon reflexes (DTRs), seizures, coma
4) GI–increased motility, hyperactive bowel sounds, abdominal cramping, anorexia, nausea, vomiting

Question 25

Lab findings associated with hyponatremia

Answer 25

1) serum Na+ – decreased < 136 mEq/L

2) serum osmolality–decreased < 280 mOsm/kg

Question 26

Hypernatremia

Answer 26

• serum sodium > 145 mEq/L
• serous electrolyte imbalance–can cause significant neurological, endocrine, and cardiac disturbances
• causes hypertonicity of serum–causes shift of water out of cells, making them dehydrated

Question 27

Risk factors for hypernatremia

Answer 27

1) water deprivation (NPO)
2) heat stroke
3) excessive Na+ intake–dietary, hypertonic IV fluids, hypertonic tube feedings, bicarbonate intake
4) excessive Na+ retention–kidney failure, Cushing’s syndrome, aldosteronism, some meds (glucocorticosteroids)
5) fluid losses–fever, diaphoresis, burns, respiratory infection, diabetes insipidus, hyperglycemia, watery diarrhea
6) age-related changes–decreased total body water content and inadequate fluid intake related to altered thirst mechanism
7) compensatory mechanisms–increased thirst and increased production of ADH

Question 28

Subjective and objective data of hypernatremia

Answer 28

1) VS–hyperthermia, tachycardia, orthostatic hypotension
2) neuromusculoskeletal–restlessness, disorientation, irritability, muscle twitching, muscle weakness, seizures, decreased LOC, reduced to absent DTRs
3) GI–thirst, dry mucous membranes, dry and swollen tongue red in color, increased motility, hyperactive bowel sounds, abdominal cramping, nausea
4) other clinical findings–edema, warm flushed skin, oliguria

Question 29

Lab findings associated with hypernatremia

Answer 29

1) serum Na+– increased, > 145 mEq/L

2) serum osmolarity–increased, > 300 mOsm/kg

Question 30

Nursing care for hypernatremia

Answer 30

1) report abnormal lab findings to provider
2) fluid loss–based on serum osmolarity (administer hypotonic IV fluids-0.225% NaCl)
3) Excess sodium–encourage water intake, discourage Na+ intake and administer diuretics (loop diuretics)
4) monitor LOC and ensure safety
5) provide oral hygiene and other comfort measures to decrease thirst
6) monitor I&O, alert provider if urinary output inadequate

Question 31

Potassium (K+)

Answer 31

• major cation in ICF
• plays vital role in cell metabolism; transmission of nerve impulses; functioning of cardiac, lung, and muscle tissues; and acid-base balance
• reciprocal action w/ Na+
• Expected levels 3.5-5 mEq/L

Question 32

Hypokalemia

Answer 32

• < 3.5 mEq/L

- result of increase loss of K+ from body or movement of K+ into the cells

Question 33

Risk factors for hypokalemia

Answer 33

• abnormal GI losses–vomiting, NG suctioning, diarrhea, inappropriate laxative use
• renal losses–excessive use of K+-excreting diuretics (furosemade (Lasix)), corticosteroids
• skin losses–diaphoresis, wound losses
• hyperadlosteronism
• insufficient K+
• inadequate dietary intake (rare)
• prolonged administration of non-electrolyte-containing IV solutions (5% dextrose in water)
• ICF–metabolic alkalosis, after correction of acidosis (treatment of DKA), during periods of tissue repair (burns, trauma, starvation), total parental nutrition (TPN)

Question 34

Subjective and objective data of hypokalemia

Answer 34

1) VS-hyperthermia, weak irregular pulse, hypotension, respiratory distress
2) neuromusculoskeletal-ascending bilateral muscle weakness w/ respiratory collapse and paralysis, muscle cramping, decreased muscle tone and hypoactive reflexes, paresthesias, mental confusions
3) ECG-PVCs, bradycardia, blocks, v-tach, flattening T waves, and ST depression
4) GI-decreased motility, hypoactive bowel sounds, abdominal distention, constipation, ileus, nausea, vomiting, anorexia
5) other clinical findings-polyuria (excretion of dilute urine)

Question 35

Lab findings associated with hypokalemia

Answer 35

1) serum potassium < 3.5 mEq/L

2) ABGs–metabolic acidosis pH > 7.45

Question 36

Diagnostic procedures associated with hypokalemia

Answer 36

ECG shows findings of dysrhythmias (PVCs, ventricular tachycardia, flattening T waves, ST depression)

Question 37

Nursing care for hypokalemia

Answer 37

1) report abnormal findings to provider
2) treat underlying cause
3) replace potassium: provide dietary education and encourage foods high in K+ (avocados, dried fruit, cantaloupe, bananas, potatoes, spinach); provide oral K+ supplementation
4) IV K+ supplementation: mixed by pharmacist and checked by 2 nurses; max. rec. rate is 10-20 mEq/hr; NEVER IV bolus (high risk of cardiac arrest)
5) monitor for phlebitis (tissue irritant)
6) monitor for and maintain adequate urine output
7) monitor for shallow, ineffective respirations and diminshed breath sounds
8) monitor cardiac rhythm and intervene promptly as needed
9) monitor clients receiving digoxin (hypokalemia increases risk of digoxin toxicity)
10) monitor LOC and ensure safety
11) monitor bowel sounds and abdominal distention and intervene as needed

Question 38

Hyperkalemia

Answer 38

• serum K+ > 5 mEq/L
• results from increased intake of K+, movement of K+ out of the cells, or inadequate renal excretion
• uncommon in clients w/ adequate renal function
• potentially life-threatening due to risk of cardiac arrhythmias and cardiac arrest

Question 39

Risk factors for hyperkalemia

Answer 39

1) increased total body K+ – IV K+ admin., salt substitutes, blood transfusion
2) ECF shift–decreased insulin, acidosis (DKA), tissue catabolism (sepsis, trauma, surgery, fever, MI)
3) hypertonic states–uncontrolled diabetes mellitus
4) decreased excretion of K+ – kidney failure, severe dehydration, K+ sparing diuretics, ACE inhibitors, adrenal insufficiency
5) older adult clients – greater risk due to decreased kidney function and medical conditions resulting in use of salt substitutes, ACE inhibitors, and K+ sparing diuretics

Question 40

Subjective and objective data of hyperkalemia

Answer 40

1) VS-slow, irregular pulse; hypotension
2) neuromusculoskeletal-irritability, confusion, weakness with ascending flaccid paralysis, parethesias, lack of reflexes
3) ECG-ventricular fibrillation, peaked T waves, widened QRS, cardiac arrest
4) GI-increased motility, diarrhea, abdominal cramps, hyperactive bowel sounds
5) other clinical findings-oliguria

Question 41

Lab findings associated with hyperkalemia

Answer 41

1) serum potassium – increased > 5 mEq/L

2) ABGs – metabolic acidosis pH < 7.35

Question 42

Diagnostic procedures associated with hyperkalemia

Answer 42

1) ECG will show dysrhythmias (ventricular fibrillation, peaked T waves, widened QRS)

Question 43

Nursing care fro hyperkalemia

Answer 43

1) report abnormal findings to provider
2) decrease K+ intake–stop infusion of IV potassium, withhold oral K+, provide K+ restricted diet, dialysis may be required for extremely high levels
3) promote movement of K+ from ECF to ICF–administer IV fluids w/ dextrose and regular insulin
4) monitor cardiac rhythm and intervene promptly as needed
5) medications to increase K+ excretion–administer loop diuretics (furosemide-Lasix) if kidney function adequate; administer sodium polystyrene sulfonate (kayexalate) orally or as enema (increase excretion from GI tract)
6) maintain IV access
7) prepare client for dialysis if prescribed

Question 44

Calcium

Answer 44

• found in body’s cells, bones, and teeth
• expected range 9-10.5 mg/dL
• balance essential for proper functioning of CV, neuromuscular, and endocrine systems, blood clotting and bone and teeth formation

Question 45

Hypocalcemia

Answer 45

-serum Ca+ < 9 mg/dL

Question 46

Risk factors for hypocalcemia

Answer 46

1) increased Ca+ output–chronic diarrhea, steatorrhea (as w/ pancreatitis–binding of Ca+ to undigested fat)
2) inadequate Ca+ intake or absorption–malabsorption syndrome (Crohn’s disease); vitamin D deficiency (alcohol use disorder, kidney failure)
3) Ca+ shift from ECF into bone or to an inactive form–repeated blood transfusion; post-thyroidectomy; hypoparathyroidism

Question 47

Subjective and objective data for hypocalcemia

Answer 47

1) muscle twitches/tetany–numbness and tingling (extremities, circumoral); frequent, painful muscle spasms at rest that can progress to tetany; hyperactive DTRs; + Chvostek’s sign (tapping facial nerve triggering facial twitching); + Trousseau’s sign (hand/finger spasms w/ sustained bp cuff inflation)
2) cardiovascular–decreased myocardial contractility (decreased HR and hypotension)
3) GI–hyperactive bowel sounds, diarrhea, abdominal cramping
4) CNS–seizures due to overstimulation of CNS

Question 48

Lab findings associated with hypocalcemia

Answer 48

-Ca+ level < 9 mg/dL

Question 49

Diagnostic procedures associated with hypocalcemia

Answer 49

-ECG–prolonged QT interval and ST segments

Question 50

Nursing care for hypocalcemia

Answer 50

1) administer oral or IV Ca+ supplements (carefully monitor respiratory and CV status)
2) initiate seizure precautions
3) keep emergency equipment on standby
4) encourage foods high in Ca+ (dairy products, dark green vegetables)

Question 51

Hypercalcemia

Answer 51

-serum Ca+ level > 10.5 mg/dL

Question 52

Risk factors for hypercalcemia

Answer 52

1) decreased Ca+ output–thiazide diuretics
2) increased Ca+ intake and absorption
3) Ca+ shift from bone to ECF–hyperparathyroidism; bone cancer; Paget’s disease; chronic immobility

Question 53

Subjective and objective data for hypercalcemia

Answer 53

1) neuromuscular–decreased reflexes; bone pain; flank pain if renal calculi develop
2) CV–dysrhythmias
3) GI–anorexia, nausea, vomiting, constipation
4) CNS–weakness, lethargy; confusion, decreased LOC

Question 54

Lab findings associated with hypercalcemia

Answer 54

-Ca+ level > 10.5 mg/dL

Question 55

Diagnostic procedures associated with hypercalcemia

Answer 55

-ECG–shortened QT interval and ST segment

Question 56

Nursing care for hypercalcemia

Answer 56

1) increase client activity level
2) limit dietary Ca+
3) encourage fluid to promote urinary excretion
4) encourage fiber to promote bowel elimination
5) implement safety precautions if client is confused
6) monitor for pathologic fractures
7) encourage acid-ash fluids (prune, cranberry juice) to decrease risk for renal Ca+ stone formation

Question 57

Magnesium

Answer 57

• most of body’s Mg is found in bones
• smaller amounts found within body cells
• very small amount found in ECF
• expected range 1.3-2.1 mEq/L

Question 58

Hypomagnesemia

Answer 58

-serum Mg level < 1.3 mEq/L

Question 59

Risk factors for hypomagnesemia

Answer 59

1) increased Mg output–GI losses (diarrhea, NG suction); thiazide or loop diuretics
2) inadequate Mg intake or absorption–malnutrition; alcohol use disorder; laxative use

Question 60

Subjective/objective data for hypomagnesemia

Answer 60

1) neuromuscular–increased nerve impulse transmission (hyperactive DTRs, paresthesias, muscle tetany); positive Chvostek’s and Trousseau’s signs
2) GI–hypoactive bowel sounds, constipation, abdominal distention, paralytic ileus
3) CV–dysrhythmias, tachycardia, hypertension

Question 61

Nursing care for hypomagnesemia

Answer 61

1) discontinue Mg-losing medications
2) administer oral or IV MgSO4 following safety protocols (IV route used because IM can cause pain and tissue damage. Oral Mg can cause diarrhea and increase Mg depletion. Monitor closely)
3) encourage foods high in Mg (whole grains and dark green vegetables)
4) implement seizure precautions

Question 62

Hypermagnesemia

Answer 62

-serum Mg level > 2.1 mEq/L

Question 63

Risk factors for hypermagnesemia

Answer 63

1) decreased Mg output–kidney failure; adrenal insufficiency
2) increased Mg intake and absorption–laxatives or antacids containing Mg

Question 64

Subjective/objective data for hypermagnesemia

Answer 64

1) neuromuscular–diminished DTRs; muscle paralysis; shallow respirations, decreased RR
2) CV–bradycardia, hypotension; dysrhythmias, cardiac arrest
3) CNS–lethargy