fluid and electrolytes

Electrolytes

potassium, sodium, calcium, magnesium

Electrolyte responsibilities

balancing water, pH level, moving waste out of cells, moving nutrients into cells, allowing body to function properly

Fluid

water containing glucose, mineral salts, and proteins, extracellular and intracellular

Extracellular fluid

outside cells, ⅓ total body water, intravascular, interstitial, and transcellular

What fluid contains sodium, chloride, and bicarbonate?

extracellular fluid

Intravascular fluid

blood plasma

Interstitial fluid

between cells, outside of blood vessels

Transcellular fluid

CSF, pleural, peritoneal, synovial

Intracellular fluid

inside cells, ⅔ total body water, balanced via membrane permeability

What fluid contains potassium, magnesium, phosphates, and proteins?

intracellular fluid

Cellular effect of isotonic solution

cells normal shape, no loss or gain

Cellular effect of hypertonic solution

cells lose water and shrink

Cellular effect of hypotonic solution

cells swell, water rushes in

Clinical dehydration

extracellular volume deficit and hypernatremia at same time, usually caused by gastroenteritis

Fluid intake

drinking and eating, food metabolism, IV, rectal, irrigation of body cavities

Fluid distribution

movement of fluid, ECF vs ICF occurs by osmosis, vascular vs interstitial ECF occurs by filtration

Fluid output

skin, lungs, GI, kidneys, insensible losses via lungs and skin

Hormones affecting fluid balance

ADH, RAAS, ANP

Extracellular fluid volume deficit causes

decreased oral intake of water and salt, increased GI output, increased renal output, loss of blood or plasma, massive sweating without water and salt intake

Extracellular fluid volume deficit signs and symptoms

sudden weight loss, postural hypotension, tachy, thready pulse, poor skin turgor, flat neck veins, dark yellow urine, restless, confusion, oliguria, cold and clammy, increased HCT, increased BUN and specific gravity

Extracellular fluid volume deficit treatment

identify underlying cause, treat underlying cause, replace fluids

Extracellular fluid volume excess causes

excess isotonic IVF, oral intake of salty foods and water, renal retention of Na and water, heart failure, cirrhosis, aldosterone or glucocorticoid excess, acute or chronic oliguric renal disease

Extracellular fluid volume excess signs and symptoms

sudden weight gain, edema, full neck veins, crackles, confusion, pulmonary edema, decreased HCT, decreased BUN

Extracellular fluid volume excess treatment

diuretics, restricting sodium and fluids, sit patient up in bed

Untreated hypovolemia

cyanosis, change in LOC, chest pain, palpitations, no urine, tachypnea, tachycardia, decreased BP, weak pulse

Hypovolemic shock

body has lost 20 percent or ⅕ of blood/fluid supply, treatment aimed at controlling fluid/blood loss

What can lead to electrolyte imbalances

dehydration, overhydration, certain medications, heart, kidney, and liver disorders, incorrect IV fluids or feedings

Normal potassium values

3.5 to 5 mEq/L

Normal sodium values

135 to 145 mEq/L

Normal calcium values

9 to 11 mEq/L

Normal magnesium values

1.5 to 2.5 mEq/L

Hypernatremia causes

loss of more water than salt (diabetes insipidus, large insensible perspiration), gain of more salt than water (tube feedings, hypertonic IVF, lack of access to water, dysfunction of osmoreceptors)

Hypernatremia s and s

decreased LOC, thirst, seizures, high serum osmolality

Hypernatremia treatment

slow and careful D5W or hypotonic fluid administration, seizure precautions, neuro checks, avoid rapid reduction of sodium

Hyponatremia causes

gain of more water than salt (excessive ADH, excess water intake, excessive D5W, hypotonic irrigation, tap water enema), loss of more salt than water (replacing large body output with water but no salt

Hyponatremia s and s

decreased LOC, seizures, low serum osmolality

Hyponatremia treatment

increase or decrease oral intake depending on cause, correct sodium levels SLOWLY to prevent cardiac overload

Hypokalemia causes

decreased intake, shift of K into cells, increased K output (N/V, diuretics)

Hypokalemia s and s

muscle weakness, abdominal distension, decreased bowel sounds, constipation, dysrhythmia, U waves, flattened T waves, ST segment depression

Hypokalemia treatment

potassium diet, oral supplements, IV, watch s and s

Hyperkalemia causes

increased K intake, shift K out of cells, insufficient insulin, decreased K output, use of K sparing diuretics, adrenal insufficiency

Hyperkalemia s and s

bilateral muscle weakness in quadriceps, abd cramps, dysrhythmia, cardiac arrest, peaked T waves, widened QRS complex, PR prolongation, terminal sine wave pattern

Hyperkalemia treatment

sodium bicarb (acidosis), calcium gluconate (dysrhythmias), insulin, increase excretion, dialysis, medications, iv fluids

Hypocalcemia causes

decreased Ca intake and absorption, shift of Ca into bone, increased Ca output

Hypocalcemia s and s

numbness of fingers, toes, and mouth, chvosteks sign, hyperactive reflexes, muscle twitching, prolonged ST segments

Hypocalcemia treatment

oral or IV Ca, may need vitamin D

Hypercalcemia causes

increased Ca intake and absorption, shift of Ca out of bone, decreased Ca output

Hypercalcemia s and s

anorexia, N/V, fatigue, decreased LOC, cardiac arrest, heart block, shortened ST segments

Hypercalcemia treatment

rehydration, mobility, oral phosphate, calcitonin, corticosteroids, iv fluids and diuretics, biphosphonates

Hypomagnesemia causes

decreased mag intake and absorption, shift of mag into inactive form, increased mag output

Hypomagnesemia s and s

positive chvosteks sign, muscle cramps, twitching, seizures, tachycardia, HTN, prolonged QT interval

Hypomagnesemia treatment

magnesium supplements, 1g for mg/hour for iv infusion

Hypermagnesemia causes

increased mag intake and absorption, decreased mag output

Hypermagnesemia s and s

lethargy, bradycardia, hypotension, flushing, respiratory depression, cardiac arrest, prolonged PR interval

Hypermagnesemia treatment

diuretics and dialysis, calcium gluconate