Fluid and Electrolytes

- maintain body temp
- maintain cell shape
- transports nutrients, electrolytes, and oxygen to cells
- excretes waste products
- lubricates joints and membranes
- medium for food digestion

Adults- 60%
Infants- 70-80%

Varies with gender, age, and body mass

Intracellular Fluid (ICF)- inside cell
Extracellular Fluid (ECF)- outside cell
Trans-cellular Fluid- specialized cavities

Input, Output

Positive
Negative

the movement of molecules from an area of high concentration to an area of low concentration. (Water movement)
Ex.- Lump of sugar in water.

Like simple diffusion, however when it is combined with a specific carrier molecule the rate of diffusion accelerates.
Ex.- Glucose transport in a cell

a process in which molecules move against the concentration gradient.
Ex.- Sodium potassium pump

the movement of WATER between two comparments seperated by a semipermeable membrane. Water moves through the membrane to the area of low solute concentration to an area of high solute concentration.

275- 295 mOsm/kg

That the concentration of particles is too great or that the water content is too little, termed water deficit.

Too little solute for the amount of water or too much water for the solute, termed water excess.

Fluids with the same osmolality as the cell interior.

Solutions in which the solutes are less concentrated than the cells.

Water moves into the cell.

Solutions in which the solutes are more concentrated than the cells.

Water moves out the cell.

the major force that pushes water out of the vascular system at the capillary level.

the force that pulls fluid into the vascular space.

First Spacing- normal distribution of fluid in ICF and ECF
Second Spacing- Abnormal accumulation of interstitial fluid. Edema
Third Spacing- Fluid accumulation in part of the body where it is not easily exchanged with ECF.

A body fluid deficit or increase in plasma osmolality is sensed by osmpreceptors which stimulates thirst and antidiuretic hormone (ADH) release. ADH causes water reabsorption resulting in increased free water in body and decreased plasma osmolality.

;Releases ADH, regulating water retention. Water is resorbed into the blood and not excreted in the urine.

Glucocorticoids and mineralocorticoids help to regulate water and electrolytes. Glucocorticoids (Cortisol) have an antiinflammatory effect and increase serum glucose levels. Mineralocorticoids (Aldosterone) enhance sodium retention and potassium excretion. When Sodium is absorbed, water folllows.

The kidneys regulate water balance by adjusting urine volume.

Natriuretic peptides are natural antagonists to the RAAS. Produced in response to increased atrial pressure and high serum sodium levels. They act on the renal tubules to promote excretion of sodium and water, resulting in a decrease in blood volume and BP.

Is the invisible vaporization from the lungs and skin, assists in regulating body temp.

- decrease in the glomerular filtration rate
- decreased creatinine clearance
- the loss of the ability to concentrate urine and conserve water
- narrowed limits for the excretion of H2O, Na, K, and H
- decrease in renin and aldosterone
- increase in ADH and ANP
- decrease in the thirst mechanism

- Illness and Conditions: GI issues, CVD, Renal disease, burns, endocrine disorders, cirrhosis of the liver, pulmonary disease
- Interventions and treatments: surgery, medications, IV fluids, NG suctioning, low Na diets, NPO status
- Stress

EVERYONE

Hypervolemia

- results from excessive intake of fluids, anormal rentention of fluids, or interstitial to plasma fluid shift, HF, Renal failure
- S/S: cough, SOB, JVD, bounding pulse, crackles, weight gain, HTN, change in LOC, peripheral edema, increased BP
- Treatment: diuretics and fluid restriction, Na might also be restricted

Hypovolemia

- results from loss of normal body fluids, decreased intake, plasma to interstitial fluid shift, diabetes insipidus, hemorrhage
- S/S: decreased urine output, concentrated urine, weakness, weight loss, orthostatic hypotension, low BP, poor skin tugor, dry mucous membranes, thirst
- treatment: balanced IV solutions given to replace both water and electrolytes

22-26 mEq/L

96-106 mEq/L

2.4- 4.4 mg/dL

3.5- 5.0 mEq/L

1.5- 2.5 mEq/L

135- 145 mEg/L

8.5- 10.3 mEq/dl

an elevated serum sodium may occur with water loss or sodium gain

a loss of sodium containing fluids, from water excess or combination of both

- IV fluids
- hypertonic tube feedings without water supplements
- inadequate water intake
- excessive water loss
- disease states: diabetes insipidus, Cushings, uncontrolled diabetes mellitus

- restlessness, agitation, twitching, seizures, coma
- intense thirst, dry, swollen tongue
- postural hypotension, decreased CVP, weight loss
- weakness, lethargy

- restlessness, agitation, twitching, seizures, coma
- intense thirst, flushed skin
- weight gain, peripheral and pulmonary edema, increased BP and CVP

If oral fluids can not be given, IV solutions of 5% dextrose in water or hypotonic solution. Must decrease Na levels gradually to prevent shift in of water back into the cells, it can cause cerebral edema. Diuretics may also be given. Dietary Na intake may be restricted

- excessive sodium loss: GI losses, renal losses, skin losses
- inadequate sodium intake: fasting diets
- excessive water gain: excessive hypotonic IV fluids
- disease states: SIADH, HF, primary hyperaldosteronism

- irritability, apprehension, confusion, dizziness, personality changes
- dry mucous membranes
- postural hypotension, decreased CVP and jugular venous filling, tachycardia, thready pulse
- cold and clammy skin

- headache, apathy, confusion, muscle spasms, seizures, coma
- nausea, vomiting, diarrhea, abdominal cramps
- weight gain, increased BP and CVP

Caused by water excess, Fluid restriction is often all that is needed.
For severe symptoms, small amounts of IV hypertonic saline solution (3% NaCl) are given.
For hyponatremia with fluid loss, treatment includes fluid replacement with sodium containing solutions.

- Transmission and conduction of nerve impulses
- Maintenance of normal cardiac rhythms
- Skeletal muscle contraction
- Acid-base balance

high serum potassium

low serum potassium

- Excess K intake: excessive or rapid parenteral administration, K containing drugs, K containing salt substitute
- Shift of K out of cells: acidosis, tissue catabolism (fever, burns), crush injury, tumor lysis syndrome
- Failure to eliminate K: renal disease, K-sparing diuretics, adrenal insufficiency, ACE inhibitors

- Irritability, anxiety
- Abdominal cramping, diarrhea
- Weakness of lower extremities
- Paresthesias
- Irregular pulse, cardiac arrhythmias
- Cardiac arrest if hyperkalemia is sudden or severe

- Eliminate oral and parenteral potassium intake
- Increase elimination of K: diuretics, dialysis, increased fluid intake
- Force K from the ECF to the ICF: administration of IV insulin with glucose or IV sodium bicarb in the correction of acidosis
- Reverse the membrane potential effects of the elevated ECF K: administering IV calcium gluconate

- Potassium loss: GI losses, renal losses, skin losses, dialysis
- Shift of K into cells: increased insulin, alkalosis, tissue repair
- Lack of K intake: stravation, diet low in K, failure to include potassium in parenteral fluids if NPO

- Fatigue, muscle weakness, leg cramps, soft, flabby muscles, decreased reflexes
- Nausea, vomiting
- weak, irregular pulse
- polyuria
- Hyperglycemia

- Giving potassium chloride supplements (orally or IV) and increasing dietary intake of potassium
- NEVER give KCl IV push or in concentrated amounts

- Blocks sodium transport
- Stabilizes cell membrane
- Transmission of nerve impluses
- Myocardial contractions
- Blood clotting
- Formation of teeth and bone
- Muscle contractions

excessive calcium
> 10.2 mg/dL

low calcium levels
< 8.6 mg/dL

- Increased total calcium: multiple myeloma, prolonged immobilization, hyperparathyroidism, Vit D overdose, thiazide diuretics, milk-alkali syndrome

- Lethargy, weakness, depressed reflexes, bone pain, fractures
- Decreased memory, confusion, personality changes, psychosis
- Anorexia, nausea, vomiting
- Polyuria, dehydration
- Nephrolithiasis
- Stupor, coma

- Decreased total calcium: chronic kidney disease, elevated phosphorus, primary hyperparathyroidism, Vit D deficiency, Mg deficiency, loop diuretics, diarrhea
- Decreased ionized Ca: alkalosis, excess admin of citrated blood

- Depression, anxiety, confusion
- Numbness and tingling in extremities and around mouth
- Hyperreflexia, muscle cramps
- Chvostek's sign
- Trousseau's sign
- Tetany, seizures

Contraction of facial muscles in response to a light tap over the facial nerve in front of the ear.

Refers to carpal spasms induced by inflating a BP cuff on the arm above the systolic pressure. Shows up within 3 minutes.

- Oral or IV Ca supplements
- Diet high in Ca rich foods
- Vit D supplements

- Function of muscle
- RBCs
- Nervous system
- Deposited with Ca for bone and tooth structure

excess of phosphate

> 4.4 mg/dL

low serum phosphate

< 2.4 mg/dL

- Renal failure
- Chemotherapeutic agents
- Enemas containing phosphorus
- Excessive ingestion
- Large Vit D intake
- Hypoparathyrodism

- Hypocalcemia
- Muscle problems, tetany
- Deposition of Ca

- Dietary phosphate should be restricted
- adequate hypdration and correction of hypocalemia can enhance the renal excretion of phosphate

Reciprocal

When there are high serum phosphate levels there are low calcium levels

- Malabsorption syndrome
- Nutritional recovery syndrome
- Glucose admin
- TPN
- Alcohol withdrawal
- Phosphate- binding antacids
- Respiratory alkalosis

- CNS dysfunction
- Muscle weakness
- Renal tubular wasting of Mg, Ca, HCO3
- Cardiac problems
- Osteomalacia

- Oral supplements of Phosphate
- Diet high in phosphate
- Severe cases require IV admin of sodium phosphate or potassium phosphate

- Influences muscle contractions and intracellular activity
- Transmission of neuromuscular activity
- Coenzyme in metabolism of protein and carbohydrates

True

high serum Mg levels

>2.5 mEg/L

low serum Mg levels

<1.5 mEg/L

- Renal Failure
- Excessive admin of Mg for treatment of eclampsia
- Adrenal insufficiency

- Lethargy, drowsiness
- Nausea, vomiting
- Deep tendon reflexes are lost, then respiratory and cardiac arrest can occur

- Focus on prevention, people at risk should stay away from Mg containing drugs
- IV admin of CaCl, in severe cases

- Diarrhea, vomiting, impaired GI absorption, prolonged malnutrition
- large urine output
- NG suction
- Poorly controlled diabetes mellitus
- Hyperaldosteronism

- Oral supplements
- Increased dietary intake
- Parenteral IV or IM Mg, in severe cases; can cause cardiac arrest if given too fast

- Confusion
- Hyperactive deep tendon reflexes
- Tremors, seizures
- can resemble hypocalcemia

Decreased- dilution of blood from fluid overload

Increased- Fluid or ECF volume depletion

Decreased- hypo-osmolarity

Increased- Hyperosmolarity

ECF volume depletion

Fluid deficit

Deficit

Increase- fluid deficit

Decrease- Overhydration