FON Chapter 22 - Fluids and Electrolytes

Causes of hypercalcemia

-Loss from bone -Immobilization -Metastatic bone cancer -Multiple myeloma -Excess intake -Dietary -Antacids containing calcium -Increased absorption Increased parathyroid hormone Increased vitamin D

Magnesium

-Normal blood level, the second most abundant cation in the intracellular fluid, is 1.5 to 2.4 mEq/L. -Majority (60%) is found in the bone, 39% in the muscle and the soft tissue, and 1% in the extracellular fluid, most of which is the cerebrospinal fluid -Dietary intake is usually 200 to 400 mg daily. The minimum daily requirement is 250 mg for the average adult, 150 mg for an infant, and 400 mg for a female during pregnancy and lactation -Major route is the kidneys. Kidneys do not conserve potassium, but they do conserve magnesium; therefore if a magnesium deficiency develops, the body will conserve magnesium at the expense of excreting potassium -Promotes regulation of serum calcium, phosphate, and potassium levels and is essential for integrity of nervous tissue, skeletal muscle, and cardiac functioning -Diets low in magnesium may create a risk for hypertension, cardiac dysrhythmias, ischemic heart disease and sudden cardiac death. Decreased intracedllular magnesium levels may contribute to the hypertension, abnormal glucose tolerance, and insulin resistance common in diabetics

Bicarbonate

-Normal level is 22 to 24 mEq/L -Acts as a buffer to neutralize acids in the body and maintain the 20:1 bicarbonate to carbonic acid ratio needed to keep the body in homeostasis -Kidneys regulate the amount of bicarbonate retained or excreted

Hyperphosphatemia

-Occurs as a result of renal insufficiency -Increased intake of phosphate or vitamin D -Signs ans symptoms of tetany, numbness, and tingling around the mouth, and muscle spasms develop

Water

-Provides an extracellular transportation route to deliver nutrients to the cells and carry waste products from the cells - Acts as a lubricant for tissues - Important functions are to aid in the maintenance of acid-base balance and to assist in heat regulation by evaporation.

Causes of hypermagnesemia

-Renal failure -Diabetic ketoacidoses with severe water loss

Cause of hypomagnesemia

-Decreased intake - prolonged malnutrition - Starvation -Impaired absorption from GI tract - alcoholism - hypercalcemia -diarrhea - draining intestinal fistula - Conditions causing large lasses of urine -Prolonged IV feedings without magnesium supplementation

Hypophosphatemia

-Dietary insufficiency -Impaired kidney function -Maldistribution of phosphate -Muscle weakness, especially affecting the respiratory muscles, sometimes occurs

Causes of Hypocalcemia

-Excess blinding of calcium ions -Large amount of citrated blood -Excess alcohol -Alkalosis -Dietary deficiency of calcium and vitamin D -Chronic renal failure -Pancreatic disease -Disease of small bowel; malabsorption -Severe diarrhea -Anticonvulsants, such as phenobarbital and phenytoin (Dilantin) -Diuretics (Lasix, Edcrin) -Draining intestinal fistulas -Deficiency of parathyroid hormone or vitamin D -Increased magnesium -Thyroid surgery (surgical removal of parathyroid glands, removal of parathyroid tumor) -Injury or disease of parathyroid gland -Severe burns -Low serum albumin levels

Signs and Symptoms of hpermagnesemia

-Hypotension -Vasodilation -Heat -Thirst -Nausea and vomiting -Loss of deep tendon reflexes -Respiratory depression Prolonged or severe excess -Coma -Cardiac arrest

Water loss is replenished in two ways

1. Ingestion of liquids and food 2. Metabolism, both of food and in body tissue

The fluid compartments are as follows

1. Intracellular (66%) 2. Extracellular (34%) a. Interstitial (27%) b. Intravascular (7%)

Hypomagnesemia

-blood levels fall into less than 1.5 mEq/L -Decrease in magnesium often parallels decreased potassium, because if the magnesium level is low, the kidneys ten to excrete more potassium -

2.2 pounds (1kg)

1 L of fluid equals how many pounds

Three considerations are important in the blood calcium level

1. Deposition and resorption of bone 2. Absorption of calcium from the GI tract 3. Excretion of calcium in urine and feces

Passive transport Processes

1. Diffusion 2. Osmosis 3. Filtration

Hyperchloremia

the increase in chloride anions represent an attempt to compensate and maintain equal numbers with the cations in the body fluid

30 mL/hr (720/24 hr)

It is necessary for the kidneys to excrete a minimum of how much of urine

Hyponatremia

Less than normal concentration of sodium in the blood

Chloride

Negatively charged extracellular anion; a salt of hydrochloric acid

Anions

Negatively charged ion that, when in solution, is at tracted to the positive electrode

Milliequivalent (mEq)

Number of grams of soluble substance dissolved in 1 mL of normal solution

The lungs

Once the buffer systems are exhausted, the body calls on the second line of defense

Osmosis

Passage of water across a selectively permeable membrane; the water moves from a less concentrated solution to a more concentrated solution

Cations

Positively charged ion that, when in solution, is attracted to the negatively charged electrode

Normal Fluid I&O in an adult eating 2500 calories per day

Water in food - 1000 - Skin - 500 Water from oxidation - 300 - Lungs - 350 Water as liquid - 1200 - Feces - 150 - Kidney - 1500

Carbonic acid

causes respiratory acidosis or alkalosis

Potassium

The dominant intracellular cation

Glomerular filtration

The fluid part of the blood that is forced through the glomerulus. It leads to an output of 1 to 2 L of urine per day.

Compartment

The fluids are in constant motion throughout the body to carry out their functions.

Nephrons

The functioning unit of the kidney. It filter blood at a rate of 125 mL/min, or about 180 L/day.

Sodium

The most abundant electrolyte in the body; the major extracellular electrolyte; it is a cation

Filtration

The transfer of water and dissolved substances from an area of higher pressure to an area of lower pressure

Blood buffers

They circulate throughout the body in pairs, neutralizing excess acids or bases by contributing or accepting hydrogen ions. One buffer will dominate if the solution is too acid; the other if the solution is too alkaline.

Hypochloremia

This is usually occurs when sodium is lost, because sodium and chloride are frequently paired.

Bicarbonate and carbonic acid

Two general types of disturbances can cause a pH imbalance

Acid-alkaline balance

Alkaline electrolyte whose major function is the regulation of the acid-base balance

Examples of anions

- Chloride (Cl-) - Bicarbonate (HCO3-) - Sulfate (SO4-) - Hydrogen phosphate (HPO4 -)

Calcium

- Normal blood level is approximately 4.5 mEq/L. - Of the 1200 g of calcium in the body, 99% is concentrated in the bones and the teeth. 1% is found in the soft tissue and the extracellular fluid - Is deposited in the bones and mobilized as needed to keep the blood level constant during any period of insufficient intake - It's removed from the body via the urine and feces - Regulate normal muscle contraction and relaxation - Help hold body cells together by establishing the thickness and strength of cell membranes - Most important functions is to act as an enzyme activator for chemical reactions in the body

Examples of cations

- Sodium (Na+) - Potassium (K+) - Calcium (Ca+) - Magnesium (Mg++)

Hydrogen ions

- the more hydrogen ions in a solution, the more acid the solution -the few hydrogen ions in a solution, the more alkaline the solution -as the numbers of hydrogen ion increase, the acidity of the solution increases and the pH decreases -the number of hydrogen ion decreases and the pH increase -a pH of less than 7.35 is acid -a pH of greater than 7.45 is alkaline -normal pH of arterial blood is 7.45 -normal pH of venous blood and interstitial fluid is approximately 7.35

DRI for calcium

-360 mg for infants - 1200 mg for females 15 to 18 yrs old - 1300 mg during pregnancy and lactation - 1000 mg/day for premenopausal women and postmenopausal women taking estrogen - 1500 mg/day for postmenopausal women who are not receiving supplemental estrogen

Signs and Symptoms of hypomagnesemia

-Anorexia -Metal changes -Agitation, depression, confusion -Dysphagia -Hyperactive deep tendon reflexes -Nausea and vomiting -Paresthesias -Tetany -Tremors -Seizures -Ataxia -Cramps, spasticity, tentany -Tachycardia -Hypotension -Cardiac dysrhythmias

Signs and symptoms of hypercalcemia

-Anorexia, nausea, vomiting -Behavioral changes, including confusion -Thirst, polyuria -Renal calculi -Decreased deep tendon reflexes -Constipation -Paralytic ileus -Lethargy, coma -Cardiac dysrhythmias, cardiac arrest -Hypertension -Decreased muscle tone -Decreased GI motility -Bone pain

Signs and symptoms of hypocalcemia

-Anxiety, confusion, irritability -Osteoporosis, pathologic fractures -Tingling around nose, mouth, ears, fingers, toes -Twitching -Muscle spasm of feet and hands -Tetany (note positive Trousseau's or Chvostek's sign) -Laryngeal sapsms -Nausea, vomiting 0Hyperactive deep tendon relfexes -Diarrhea -Cardiac dysrhythmias, cardiac arrest -Calcium deposits in body tissues -Deminished response to digitalis glycosides

Hypermagnesemia

-Blood levels exceed 2.5 mEq/L

Phosphorus

-The normal blood level of an intracellular anion is approximately 4 mEq/L -Phosphorus and calcium have an inverse relationship in the body: an increase in one causes a decrease in the other -The majority (70% to 80%) of phosphorus is found combined with calcium in an individual's bones and teeth. 10% is in the muscle, and the remaining 10% is in the nerve tissue of the body -Dietary intake is usually 800 to 1500 mg/day. -Minimum daily requirement is 800 mg -Higher intake during pregnancy and lactation is needed -Kidneys are responsible for approximately 90% of the excretion of phosphorus, the remainder is in the feces -Acts as a buffer to regulate the body's acid-base balance -Promotes effectiveness of many of the B vitamins -Assists in normal nerve and muscle activity, and participates in carbohydrate metabolism

Hypokalemia

A decrease in the body's potassium to a level less than 3.5 mEq/L

Hydrostatic pressure

A force of fluid pressing outward on a vessel wall

Bicarbonate

A main anion of the extracellular fluid

Semipermeable membrane

A membrane that allows some molecules to pass through but does not allow other molecules to pass through

70% to 80%

A newborn's body weight is comprised of how many water percentage

Diffusion

A process in which solid particles in a fluid move from an area of higher concentration to an area of lower concentration

Homeostasis

A relative constancy in the internal environment of the body, naturally maintained by adaptive responses that promote healthy survival

Hypertonic

A solution of higher osmotic pressure; solutions pull fluid from the cells

Hypotonic

A solution of lower osmotic pressure; solutions move into the cells, causing them to enlarge

Adenosine Triphosphate (ATP)

A substance produced in the mitochondria from nutrients and is capable of releasing energy that in turn enables the cell to work

Hydration

A urine specific gravity of less than 1.010 indicates concentrated urine

Dehydration

A urine specific gravity of more than 1.030 indicates concentrated urine

Hypertonic, isotonic, hypotonic

According to the electrolyte concentration, solutions are classified in the body as

Hyperkalemia

An increase in the body's serum potassium level greater than 5 mEq/L

90%

An infant's body weight is comprised of how many water percentage

Hypercalcemia

Calcium levels exceed 5.8 mEq/L

Bicarbonate

Causes metabolic acidosis or alkalosis

Phosphorus

Chiefly, an intracellular anion in fluid of the body

Hypocalcemia

Develops when the serum level is less than 4.5 mEq/L

Ions

Electronically charged particle resulting from the breakdown of an electrolyte; negatively or positively charged.

Interstitial

Fluid between the cells or in the tissues of the body

Intracellular

Fluid inside the cells of the body

Intravascular

Fluid or plasma within the vessels of the body

Extracellular

Fluid outside the cells of the body

Hypernatremia

Greater than normal concentration of sodium; exceeds 145 mEq/L

Isotonic

Having equal tension designating or of a salt solution. Having the same osmotic pressure as blood

Acid-base balance

Homeostasis of the hydrogen ion (H+) concentration in the body fluids

10% loss is serious and 20% loss is fatal

How much of a percentage of body fluid need to be loss to be serious and how much percentage is fatal for an adult

5% is serious, 10% is very serious, and 15% is fatal

How much of a percentage of body fluid need to be loss to serious for infant

Urine specific measurements

How to determine a patient's hydration or dehydration levels

Carbonic acid to bicarbonate in the extracellular fluid

Hydrogen ion concentration is

Four primary types of acid-base imbalance

Respiratory acidosis, respiratory alkalosis, metabolic acidosis, metabolic alkalosis

The bicarbonate

Responsible mainly for buffering blood and interstitial fluid. Decreasing the strength of potentially damaging acids and bases reduces the danger these chemicals pose to pH balance. the kidney assist in regulating production of bicarbonate. The lungs assist by regulating the production of carbonic acid, which results from combing carbon dioxide and water.

The body has four major buffer systems

The bicarbonate (the most important), phosphate, protein, and hemoglobin buffer system

Blood buffers, the respiratory system, kidney

The body has three systems that work to keep the pH in the narrow range of normal

Chemical activity of hydrogen

The chemical activity of an electrolyte is compared with

Calcium

Silvery yellow metal; the most abundant mineral in the body; a positively charged ion, known as a cation.

Electrolytes

Substance that is sometimes called a mineral or salt; develops tiny electrical charges when dissolved in water and breaks up into particles known as ions

Active transport

The movement of glucose into the cells occurs through the process of what kind of transport

Active transport

The movement of materials across the membrane of a cell by means of chemical activity, which allows the cell to admit larger molecules than would otherwise be able to enter

Passive transport

The movement of small molecules across the membrane of a cell by diffusion; no cellular energy is required

45% to 55%

The percentage water makes up in the body declines from that highest percentage at birth to 50% to 60% in adults and what in the older adult.

Magnesium

The second most abundant cation in the intracellular fluid of the body

Kidneys

The third line of defense after the lungs are, their response takes hours to days

Vitamin D, calcitonin, and parathyroid hormone (parathormone)

What are necessary for the absorption and utilization of calcium

Intracellular and extracellular

What are the body two primary fluid compartments

2500mL

What is the approximately daily water I&O

200 to 2500 mg

What is the average daily intake for calcium

Causes of Hypokalemia

• Decreased potassium intake • Increased potassium loss • Increased aldosterone activity • GI losses (vomiting, diarrhea, GI suctioning) • Illeostomy • Potassium-losing diuretics • Loss from cells, as in trauma, burns, fistulas • Skin losses, diaphoreses • Conditions causing very large urine output • Potassium shift into cells • Treatment of acidosis • Metabolic alkalosis • Villous adenoma (tumor of the intestine that produces potassium-containing mucus)

Signs and symptoms of hypernatremia

• Dry, tenacious mucous membranes • Low urinary output • Firm, rubbery tissue turgor • Restlessness, agitation, confusion, flushed skin

Hyperkalaemia

• Excess in renal disease, in which potassium is not excreted adequately • When severe tissue damage occurs, potassium is released from the cells

Severe or prolonged excess of hyperkalemia

• Flaccid paralysis • Cardiac arrest • Anuria

Severe or prolonged deficit of hypokalemia

• Flaccid paralysis • Kidney damage • Paralytic ileus • Cardiac or respiratory arrest

Signs and symptoms of hyponatremia

• Headache • Irritability • Muscle weakness, muscle twitiching, tremors • Fatigue • Apathy • Postural hypotension • Nausea and vomiting • Abdominal cramps • Apprehension

Causes of hyponatremia

• Inadequate sodium intake • Loss of GI fluids • Vomiting • Diarrhea • GI or biliary drainage via nasogastric tube or T-tube • Fistulas • Loss through skin • Diaphoreses • Large open lesions (burn) • Shifting of body fluids • Massive edema • Ascites • Burns • Small bowel obstruction • Lengthy hydrotherapy

Sodium- containing internal secretions produced every day

• Intestinal (3000 mL) • Bile (700 mL) • Pancreatic (1200 mL) • Saliva (1300 mL) • Gastric (2000 mL)

Hypokalemia

• Major cause is renal excretion • Intestinal fluid contain large amounts of potassium • Conditions that cause injury to the cells in turn cause the release of potassium from the cells to the interstitial spaces and ultimately to the kidneys. • Capacity to affect skeletal and cardiac function

Severe or prolonged excess of hypernatremia

• Manic excitement • Tachycardia • Death

Nursing interventions for hyponatremia

• Monitor I&O of patients receiving diuretic medications • Monitor and record vita signs, especially blood pressure and pulse • Monitor neurologic status frequently; report any change in level of consciousness • Weigh patient daily • Monitor skin turgor at least every 8 hours • Restrict fluid intake as ordered, because this is primary treatment for dilutional hyponatremia; post a sign about fluid restriction in the patient's room • Observe for abnormal GI, renal, or skin losses • Replace fluid loss with fluids containing sodium, not plain water

Nursing interventions for hypernatremia

• Monitor and record vital signs, especially blood pressure and pulse • Provide a safe environment for confused or agitated patient • Monitor I&O • Weigh daily to check for body fluid loss • Decrease sodium intake in diet • Monitor water loss from fever, infection, increased respiratory rate • Monitor serum sodium level

Causes of hypernatremia

• More water than odium is lost from the body • Abnormally large intake of sodium • Taking too many salt tablets • IV saline infusd too rapidly • Prepared foods: frozen, canned, smoked • Dairy products in large amounts • Consumption of antacids containing sodium

Sodium

• Normal blood level is 134 to 142 mEq/L • Intracellular level is approximately 10 mEq • Is a substance that it is frequently necessary to limit in the diet rather than encourage • Kidneys are the primary excretion route • Not only pass into and out of the body, but also move back and forth between a number of body fluids during each 24 hour period • More than 8 L of fluid containing 1000 to 13000 mEq of sodium are poured into the digestive system • Source are: cheese, table salt, seafood, processed meat, canned vegetables, canned soups, ketchup, and snack foods • It regulated the water balance; where sodium is, water will follow • It also increases cell membrane permeability • It stimulates conduction of nerve impulses and helps maintain neuromuscular irritability • Control contractility of muscles, especially the heart

Chloride

• Normal blood level is 96 to 105 mEq/L • Chief anion in interstitial and intravascular fluid • Can be diffuse quickly between the intracellular and extracellular compartments • It mostly more combines with sodium (sodium chloride) or with potassium (sodium chloride) • Daily requirement is 3.65 to 10.85 g/day • Main route of excretion is through the kidneys • Necessary for the formation of hydrochloric acid in gastric juice • Valuable electrolyte in regulating the osmotic pressure between the compartments and assisting in the regulation of acid-base balance

Potassium

• Normal blood serum level is 3.5 to 5 mEq/L • Is an intracellular electrolyte • Intracellular level of is much higher at 150 mEq/L • 98% is in the cells and 2% is in the extracellular fluid • The average daily intake is 60 to 100 mEq • The routes of excretion are the kidneys (80% to 90%) and in the feces and perspiration (10% to 20%). Kidneys prefer to conserve sodium • Sodium will be reabsorbed and potassium will be excreted • Any condition that causes a decrease in urine output also causes potassium retention • Too much affects the heart muscles and disturbance in cardiac rhythm (dysrhythmia) • Main function is regulation of water and electrolyte content within the cell • Another function is to control the hydrogen ion concentration • When potassium moves out of the cell, sodium and hydrogen ions move in

Hyponatremia

• Occurs when the sodium drops to less than 134 mEq/L in the extracellular fluid • When a deficiency results from sodium loss, the body attempts to compensate by decreasing water excretion • Occurs because water is being retained in the body, which has a diluting effect on all of the blood components • As sodium levels decrease in the extracellular fluid, water is pulled into the cells, causing them to become edematous, and as the fluid moves into the cells, potassium is shifted out; there the patient is likely to also have a potassium imbalance

Causes of hyperkalemia

• Potassium intake (parenteral or oral) in excess of kidney's ability to excrete • Excessive use of salt substitutes • Renal failure • Adrenal insufficiency • Potassium enters the bloodstream from injured cells with extensive trauma (shift of potassium out of the cells into extracellular fluid) • Metabolic acidosis • Infusion of large volume of blood nearing expiration date • Beta blockers • Potassium-sparing diuretics • Tumor lysis syndrome after chemotherapy • Angiotensin-converting enzyme inhibitors • Nonsteroidal anti-inflammatory drugs • Aminoglycosides

Severe or prolonged deficit of hyponatremia

• Shock • Altered level of consciousness (lethargy, confusion) • Seizures • Coma • Altered level of consciousness usually accompanies a serum sodium level less than 125 mEq/L and indicates that the patient's condition is deteriorating

Signs and symptoms of hyperkalemia

• Signs and symptoms are often nonspecific; serum potassium level and electrocardiogram (ECG) tracings are often the best clinical indicators • Irritability • Nausea, vomiting • Diarrhea, colic • Cardiac dysrhythmias • ECGG changes • Irregular pulse rate • Hypotension • Numbness, tingling • Paresthesias • Skeletal muscle weakness, especially of lower extremities

Sign and symptoms of hypokalemia

• Skeletal muscle weakness (especially in lower extremities), leg cramps • Paresthesias, hyporeflexia • Decreased bowel sounds, cramps, and constipation, anorexia, nausea, vomiting • Diminished deep tendon reflexes, lethargy, confusion; paralysis involving the respiratory muscles; coma • Orthostatic hypotension • Cardiac dysrhythmias; weak, irregular pulse • ECG changes • Poluria