Health and Illness Course 2: Comprehensive Overview of Electrolyte Balance

Define electrolyte balance

Interplay of electrolyte intake, absorption, distribution, and output to maintain homeostasis

What are the defining criteria for electrolyte balance?

1. Appropriate intake

2. Optimal distribution

3. Adequate intake/output to achieve proper osmolality

Excessive aldosterone leads to what disease? Too little aldosterone leads to what disease?

Too much = Cushing's disease; Too little = Addisons Disease

When is aldosterone secreted?

When sodium is low

What does aldosterone cause?

sodium and water retention

What is another name for antidiuretic hormone?

Vasopressin

When is ADH secreted/

When sodium is high

What does ADH do?

Retain water and excrete sodium

What is SIADH

Syndrome of inappropriate ADH; excess ADH results in hypervolemia meaning diluted electrolytes

What is diabetes insipidus?

Deficit of ADH results in hypovolemia causing concentrated electrolytes

What do brain natriuretic peptides do?

Inhibit kidneys reabsorption of sodium causing sodium and water loss

What are the critical values for sodium?

<120 or >160

What is the normal value of sodium?

136-145 mEq

What is the overall function for sodium?

conduct impulses, contract and relax muscles, fluid distribution

What are some signs and symptoms of hyponatremia? (CNS, muscular, GI, CV?)

Decreased excitable membrane depolarization and cellular swelling.

CNS - edema, IICP, lethargy, confusion, seizures, coma

Neuromuscular - decreased DTR, muscle weakness

GI - increased motility - cramping, nausea, diarrhea

CV - depends on vascular volume

What are eight causes of hyponatremia?

1. Diuretics

2. GI losses

3. Inadequate intake

4. Excessive diaphoresis

5. Fluid overload

6. CHF

7. Aldosterone deficiency

8. SIADH

What is the treatment for hyponatremia?

1. Increase Na+ intake

2. Restrict oral fluids

3. Strict I&O

4. Daily weight

5. Initiate seizure precautions

6. Monitor response to tx (neuro exam, Urine specific gravity, serum Na+, blood pressure, prevent hypernatremia and fluid overload)

What are some medications you could give someone with hyponatremia?

1. Hypertonic saline

2. Lithium carbonate

3. Conivaptan or tolvaptan (ADH inhibitors)

What are seizure precautions? (SLORP)

1. Oxygen and suction apparatus

2. Rails up and padded

3. Patient in side lying position asap

4. Bed in lowest position

5. Privacy asap

What are seven causes of hypernatremia?

1. Dehydration

2. Fever

3. Acute renal failure

4. Hypertonic enteral feeding w/o water bolus

5. Diabetes insipidus

6. Cushing syndrome

7. Corticosteroids

What are signs and symptoms of hypernatremia?

CNS: Extreme thirst, agitation

CV: depends on vascular volume

Muscular: Muscle twitching; as Na gets higher = decreased/absent DTR

GI: dry/sticky tongue/mucosa

Skin: Dry, flushed skin

How do you treat hypernatremia?

1. Increase h2o

2. restrict sodium

3. Strict I&O

4. Daily weight

5. Monitor response to tx (neuro, urine specific gravity, vitals)

What are medications to treat hypernatremia?

1. Hydration therapy (0.9% NS or 0.45% NS)

2. Diuretics (lasix to promote Na loss)

3. Dialysis

What electrolyte when corrected too quickly can cause demyelination?

Sodium

What are normal values for potassium?

3.5-5.0 mEq/L

What are critical values for potassium?

<2.8 or >6.2

What are some causes of hypokalemia?

1. Loop/thiazide diuretics

2. GI losses

3. Inadequate intake

4. Hyperinsulinism

5. Corticosteroids

6. Cushing's syndrome

What is the overall function of potassium?

Cellular excitability

What are some signs and symptoms of hypokalemia?

1. Respiratory muscle weakness

2. Skeletal muscle weakness (decreased DTR-paralysis)

3. CV: thready pulse, orthostatic hypotension, bradycardia

4. Decreased bowel motility: n/v, constipation, ileus, distention

5. CNS: fatigue, confusion, paresthesias

What is the treatment for hypokalemia?

1. ECG monitoring

2. Respiratory assessment

3. Encourage foods high in K

4. Use caution w/ digitalis

5. use caution if patient is receiving TPN

What are some medications that can be used for hypokalemia?

K+ supplement (always assess renal fxn before administration and never give IV push)

What are some causes of hyperkalemia?

1. Potassium sparing diuretics

2. Renal failure

3. Addison's disease

4. Use of salt substitutes

5. Cellular destruction

6. Lack of insulin

What are some signs and symptoms of hyperkalemia?

CV: bradycardia, hypotension, tall peaked T waves, heart block, cardiac arrest, ventricular fibrillation

Neuro: muscle twitching, paresthesias -> muscle weakness, flaccid paralysis -> respiratory failure

GI: Increased motility and diarrhea

What is the treatment for hyperkalemia?

1. ECG monitoring

2. Eliminate K from all meds/IV solutions

3. Restrict potassium

4. Avoid salt substitutes

5. Assess CV, Neuromuscular, and GI

What are some medications for hyperkalemia?

1. Patiromer or Kayexalate (excretes K+ in the stool)

2. Administer 50% glucose w/ regular insulin (monitor blood glucose)

3. Calcium gluconate for cardiac dysrhythmias

4. Dialysis if K+ is critically high

What is the normal value for calcium?

9-10.5 mg/dL

What are the critical values for calcium?

<6 or >13 mg/dL

What two electrolytes have an inverse relationship?

Calcium and phosphate

What does calcitonin do?

Lowers blood calcium levels

What does parathyroid hormone do?

Regulate calcium and phosphorus metabolism

What does hyperparathyroidism do to calcium levels?

Causes hypercalcemia/hypophosphatemia

What does hypoparathyroidism do to calcium levels?

Cause hypocalcemia/hyperphosphatemia

What ares some causes of hypocalceimia?

1. chronic diarrhea

2. inadequate intake

3. Vitamin D deficiency

4. Malabsorption syndromes

5. Acute pancreatitis

6. Hyperphosphatemia

7. Hypoparathyroidism

What is the function of calcium?

Regulate heart rhythms, muscle contraction, blood clotting and bone density

What are some signs and symptoms of hypocalcemia?

1. Increased DTR: Tetany, trousseau and chvosteks sign, paresthesias in hands/feet, lips, nose and ears

2. Bones become less dense

3. CV: hypotension, weak pulse, prolonged QT interval

4. Increased peristalsis

5. CNS: anxiety, irritability, seizures

6. Skin: dry, brittle hair and nails

What is trousseau's sign?

What is Chvostek's sign?

What is the treatment for hypocalcemia?

1. ECG monitoring

2. Implement seizure precautions (and reduce environmental stimuli)

3. Diet high in calcium

4. Beware of digitalis if giving calcium IV

What medications can you give for hypocalcemia?

1. IV calcium gluconate

2. Administer calcium carbonate

3. Administer vitamin D

Administer phosphate binding meds in patients with renal disease

What are causes of hypercalcemia?

1. Hyperparathyroidism

2. Vitamin D overdose

3. Lithium use

4. Malignancy

5. corticosteroid therapy

6. Thiazide diuretics

7. Renal failure

8. Immobility

9. Excessive oral intake of calcium or vitamin D

What are signs and symptoms of hypercalcemia?

CV: Mild: tachycardia and HTN, Severe or prolonged: decreased HR, heart blocks, cardiac arrest

Neruomusc: decreased DTR, weakness, confused

Skeletal: fractures, deep bone pain

GI: decreased motility

What is the treatment for hypercalcemia?

1. Monitor I&O

2. Monitor vitals

3. Assess for mental status changes

4. Eliminate calcium in diet and meds

5. Encourage large amounts of fluid (3-4L/day)

6. Mobilize pt

7. Partial parathyroidectomy

What are some medications for hypercalcemia?

1. Hydration therapy

2. IV phosphate

3. Loop diuretics

4. IM calcitonin for hypercalcemic crisis (emergency)

5. Renal dialysis

What are the normal values for magnesium?

1.8-2.6 mg/dL

What are the critical values for magnesium?

<1.0 or >6.0

What is the primary function of magnesium?

Muscle relaxation

What are some causes of hypomagnesemia?

1. Loop/thiazide diuretics

2. GI losses

3. Malabsorption disorders

4. Inadequate intake

5. Alcohol use disorders

What are signs and symptoms of hypomagnesemia?

CV: Increased cardiac activity (tachycardia, a-fib vent-fib, MI)

Neuromuscular: Tense muscles (tetany, increased DTR, seizures, chvostek and trosseau's signs)

GI: decreased motility (constipation, n/v, cramping)

What is the treatment for hypomagnesemia?

1. Seizure precautions

2. Cardiac monitoring

3. Can treat with diet if mild

What medications can be used to treat hypomagnesemia?

1. IV magnesium sulfate

2. Magnesium oxide or gluconate PO

3. Include magnesium if TPN

What is important to know about IV magnesium sulfate?

1. never give IV push

2. monitor DTR

3. Monitor urine output

4. Stop IV infusion if urine output <100 mL in 4 hours

What are some causes of hypermagnesemia?

1. Acute or chronic kidney disease

2. Antacids containing magnesium

3. Large amounts of IV mag given to treat HTN in pregnancy

4. Adrenal insufficiency

What are some signs and symptoms of hypermagnesemia?

CV: decreased cardiac activity (bradycardia, vasodilation, MI, hypotension)

CNS: suppression (drowsy, lethargic, coma)

Neuromuscular: muscle weakness (decreased DTR)

Respiratory: Depression

What is the treatment for hypermagnesemia?

1. Avoid Mg in meds/diet

2. Cardiac monitoring

3. Monitor kidney fxn

4. Monitor RR and BP

5. monitor DTR

6. Mechanical ventilation for respiratory failure

What medications are given for hypermagnesemia?

1. Give fluids to excrete magnesium if kidneys functioning.

2. Renal dialysis (if kidneys not functioning)

3. Loop diuretics

4. IV calcium gluconate (emergencies)

What is the normal value for phosphate?

2.5-4.5 mg/dL

What are critical values for phosphate?

<1.5 mg/dL

What are causes of hypophosphatemia?

1. Intestinal malabsorption or malnutrition

2. Hyperparathyroidism

3. Excessive use of antacids or diuretics

What are signs and symptoms of hypophosphatemia?

CNS: confusion, seizures

Neuromuscular: Muscle weakness, bone pain, paresthesias

Respiratory: Decreased RR -> Failure

What is the treatment for hypophosphatemia?

1. Fall bundle and seizure precautions

2. Encourage high phosphorus diet - add to tube feedings

What medications can be given for hypophosphatemia?

1. PO phosphates with vitamin D

2. IV phosphorus limited to those with severe hypophosphatemia

What are causes of hyperphosphatemia?

1. Increased intake

2. Acute/chronic renal failure

3. hypoparathyroidism

4. Excess vitamin D intake

5. Muscle necrosis - rhabdomyolysis

What are signs and symptoms of hyperphosphatemia?

Neuromuscular: Increased muscle excitability (tetany, chvostek and trousseau's sign, increased DTR)

GI: n/v, anorexia

What is the treatment for hyperphosphatemia?

1. Seizure precuations

2. Neuro assessment

3. Avoid foods with phosphate

4. Increase fluids

5. Renal dialysis

What are medications given for hyperphosphatemia?

1. Calcium supplements (if calcium deficient)

2. Phosphate binders w/ meals

3. Calcitriol

4. Loop diuretics

5. Hydration therapy

What are some foods high in calcium?

1. Dairy produts

2. Green leafy vegetables

3. Canned salmon and sardines/fresh oysters

What are some foods high in potassium?

1. Bananas, oranges, cantaloupe, honeydew melon, apricotes, grapefruit

2. Dried fruits

3. Legumes, whole grains

4. Spinach/leafy greens

5. potatoes/sweet potatoes

6. Juices

7. Meats, poultry, fish

What are some foods high in magnesium?

1. Pumpkin seeds

2. Nuts

3. Spinach

4. Soymilk

5. black beans/kidney beans/black-eyed peas

6. Dark chocolate

7. Whole wheat bread

8. Avocados

9. potatoes

10. Rice

11. Salmon, halibut, mackerel and pollock

12. Broccoli

What are some foods high in sodium?

1. Bread and rolls

2. Pizza

3. Sandwiches

4. Cold cuts/meats

5. Soup

6. Burritos/tacos