FLUIDS AND ELECTROLYTES

Question 1

Thid-Spacing

Answer 1

Third-spacing is the accumulation and sequestration of trapped extracellular fluid in an actual or potential body space as a result of disease or injury.

The trapped fluid represents a volume loss and is unavailable for normal physiological processes.

Fluid may be trapped in body spaces such as the pericardial, pleural, peritoneal, or joint cavities; the bowel; the abdomen’ or within soft tissues after trauma or burns.

Assessing the intravascular fluid loss caused by third-spacing is difficult The loss may not be reflected in weight changes or intake and output records and may not become apparent until after organ malfunction occurs

Question 2

EDEMA

Answer 2

Edema is an excess accumulation of fluid in the interstitial space’ it occurs as a result of alterations in oncotic pressure, hydrostatic pressure, capillary permeability, and lymphatic obstructions.

Localized edema occurs as a result of traumatic injury from accidents or surgery, local inflammatory processes, or burns.

Generalized edema, also called anasarca, is an excessive accumulation of fluid in the interstitial space throughout the body and occurs as a result of conditions such a cardiac, renal, or liver failure.

Question 3

BODY FLUID

Answer 3

Body fluids transport nutrients to the cells and carry waste products from the cells.

Total body fluid (intracellular and extracellular) amounts to about 60% body weught in the adult, 55% in the older adult, and 80% in the infant.

Thus infants and older adults are at a higher risk for fluid-related problems than younger adults; children have a greater proportion of body water than adults,, and the other older adult has the least proportion of body water.

Body fluids consist of water and dissolved substances.

The largest single fluid constituent of the body is water.

Some substances, such as glucose, urea, and creatining, do not dissociate in solution; that is, they do not separate from their complex forms into simpler substances when they are in solution.

Other substances do dissociate; for example, when sodium chloride is in a solution, it dissociates, or separates, into 2 parts or elements.

INFANTS AND OLDER ADULTS NEED TO BE MONITORED CLOSELY FOR FLUID IMBALANCES.

Question 4

Body fluid transport - DIFFUSION

Answer 4

Diffusion is the process whereby a solute (substance that is dissolved) may spread through a solution or solvent (solution in which the solute is dissolved).

Diffusion of a solute spreads the molecules from an area of higher concentration to an area of lower concentration.

A permeable membrane allows substances to pass through it without restriction.

A selectively permeable membrane allows some solutes to pass through without restriction but prevents other solutes from passing freely.

Diffusion occurs within fluid compartments and from one compartment to another if the barrier between the compartments is permeable to the diffusing substances.

Question 5

BODY FLUID TRANSPORT - OSMOSIS

Answer 5

Osmosis is the movement of solvent molecules across a membrane in response to a concentration gradient,
usually from a solution of lower to one of higher solute concentration.

Osmotic pressure is the force that draws the solvent from a less concentrated solute through a selectively permeable membrane into a more concentrated solute, thus tending to equalize the concentration of the solvent.

If a membrane is permeable to water but not to all solutes present, the membrane is a selective or semipermeable membrane.

When a more concentrated solution is on one side of a selectively permeable membrane and a less concentrated solution is on the other side, a pull called osmotic pressure draws the water through the membrane to the more concentrated side, or the side with more solute.

Question 6

BODY FLUID TRANSPORT - Filtration

Answer 6

Filtration is the movement of solutes and solvents by hydrostatic pressure.

The movement is from an area of higher pressure to an area of lower pressure.

Question 7

BODY FLUID TRANSPORT - Hydrostatic pressure

Answer 7

Hydrostatic pressure is the force exerted by the weight of a solution.

When a difference exists in the hydrostatic pressure on two sides of a membrane, water and diffusible solutes move out of the solution that has the higher hydrostatic pressure by the process of filtration.

At the arterial end of the capillary, the hydrostatic pressure is higher than the osmotic pressure; therefore, fluids and diffusible solutes move out of the capillary.

At the venous end, the osmotic pressure, or pull, is higher than the hydrostatic pressure, and fluids and some solutes move into the capillary.

The excess fluid and solutes remaining in the interstitial spaces are returned to the intravascular Compartment by the lymph channels.

Question 8

BODY FLUID TRANSPORT - Osmolality

Answer 8

Osmolality refers to the number of osmotically active particles per kilogram of water; it is the concentration of a solution.

In the body, osmotic pressure is measured in milliosmoles (mOsm).

The normal osmolality of plasma is 275 to 295 mOsm/kg (275 to 295 mmol/kg).

Question 9

Movement of body fluid

Answer 9

Cell membranes and capillary walls separate body compartments.

Cell membranes are selectively permeable; that is, the cell membrane and the capillary wall allow water and some solutes free passage through them.

Several forces affect the movement of water and solutes through the walls of cells and capillaries; for example, the greater the number of particles within the cell, the more pressure exists to force the water through the cell membrane out of the cell.

If the body loses more electrolytes than fluids, as can happen in diarrhea, then the extracellular fluid contains fewer electrolytes or less solute than the intracellular fluid.

Fluids and electrolytes must be kept in balance for health; when they remain out of balance, death can occur.

Question 10

Isotonic solutions

Answer 10

When the solutions on both sides of a selectively permeable membrane have established equilibrium or are equal in concentration, they are isotonic.

Isotonic solutions are isotonic to human cells, and thus very little osmosis occurs; isotonic solutions have the same osmolality as body fluids.

Question 11

Hypotonic solutions

Answer 11

When a solution contains a lower concentration of salt or solute than another, more concentrated solution, it
is considered hypotonic.

A hypotonic solution has less salt or more water than an isotonic solution; these solutions have lower osmolality than body fluids.

Hypotonic solutions are hypotonic to the cells; therefore, osmosis would
continue in an attempt to bring about balance or equality.

Question 12

Hypertonic solutions

Answer 12

A solution that has a higher
concentration of solutes than another, less concentrated solution is hypertonic; these solutions have a higher osmolality than body fluids.

Question 13

Osmotic pressure

Answer 13

The amount of osmotic pressure is determined by the concentration of solutes in solution.

When the solutions on each side of a selectively permeable membrane are equal in concentration, they are isotonic.

A hypotonic solution has less solute than an isotonic solution, whereas a hypertonic solution contains more solute.

Question 14

Active transport

Answer 14

If an ion is to move through a membrane from an area of lower concentration to an area of higher concentration, an active transport system is necessary.

An active transport system moves molecules or ions against concentration and osmotic pressure.

Metabolic processes in the cell supply the energy for active transport.

Substances that are transported actively through the cell membrane include ions of sodium, potassium, calcium, iron, and hydrogen; some of the sugars; and the amino acids.

Question 15

Body fluid intake

Answer 15

Water enters the body through 3 sources—orally ingested liquids, water in foods, and water formed by oxidation of foods.

About 10 mL of water is released by the metabolism of each 100 calories of fat, carbohydrates, or proteins.

Question 16

Body fluid output

Answer 16

Water lost through the skin is called insensible loss (the individual is unaware of losing that water).

The amount of water lost by perspiration varies according to the temperature of the environment and of the body.

Water lost from the lungs is called insensible loss and is lost through expired air that is saturated with water vapor.

The amount of water lost from the lungs varies with the rate and the depth of respiration.

Large quantities of water are secreted into the gastrointestinal tract, but almost all of this fluid is reabsorbed.

A large volume of electrolyte-containing liquids moves into the gastrointestinal tract and then returns again to the extracellular fluid.

Severe diarrhea results in the loss of large quantities of fluids and electrolytes.

The kidneys play a major role in regulating fluid and electrolyte balance and excrete the largest quantity of fluid.

Normal kidneys can adjust the amount of water and electrolytes leaving the body.

The quantity of fluid excreted by the kidneys is determined by the amount of water ingested and the amount of waste and solutes excreted

As long as all organs are functioning normally, the body is able to maintain balance in its fluid content.

Question 17

Maintaining Fluid and Electrolyte Balance

Answer 17

Homeostasis is a term that indicates the relative stability of the internal environment.

Concentration and composition of body fluids must be nearly constant.

When one of the substances in a client is deficient— either fluids or electrolytes—the substance must be replaced normally by the intake of food and water or by therapy such as intravenous (IV) solutions and medications.

When the client has an excess of fluid or electrolytes, therapy is directed toward assisting the body to eliminate the excess.

Question 18

Maintaining Fluid and Electrolyte Balance

Answer 18

The kidneys play a major role in controlling balance in fluid and electrolytes.

Question 19

Maintaining Fluid and Electrolyte Balance

Answer 19

The adrenal glands, through the secretion of aldosterone, also aid in controlling extracellular fluid volume by regulating the amount of sodium reabsorbed by the kidneys.

Question 20

Maintaining Fluid and Electrolyte Balance

Answer 20

Antidiuretic hormone from the pituitary gland regulates the osmotic pressure of extracellular fluid by regulating the amount of water reabsorbed by the kidneys.

IF THE CLIENT HAS A FLUID OR AN ELECTROLYTE IMBALANCE, THE NURSE MUST CLOSELY MONITOR THE CLIENT’S CARDIOVASCULAR, RESPIRATORY, NEUROLOGICAL, MUSCULOSKELETAL, RENAL, INTEGUMENTARY, AND GASTROINTESTINAL STATUS.

Question 21

Fluid Volume Deficit

Answer 21

Dehydration occurs when the fluid intake of the body
is not sufficient to meet the fluid needs of the body.

The goal of treatment is to restore fluid volume, replace electrolytes as needed, and eliminate the cause of the fluid volume deficit.

Question 22

Isotonic dehydration

Answer 22

a. Water and dissolved electrolytes are lost in equal proportions.

Known as HYPOVOLEMIA, isotonic dehydration is the MOST COMMON type of dehydration.

Isotonic dehydration results in decreased circulating blood volume and inadequate tissue perfusion.

CAUSES OF FLUID VOLUME DEFICITS

a. Inadequate intake of fluids and solutes
b. Fluid shifts between compartments volume deficits

C. Excessive losses of isotonic body fluids

Question 23

Hypertonic dehydration

Answer 23

Water loss exceeds electrolyte loss.

The clinical problems that occur result from alterations in the concentrations of specific plasma electrolytes.

Fluid moves from the intracellular compartment into the plasma and interstitial fluid spaces, causing cellular dehydration and shrinkage.

CAUSES OF FLUID VOLUME DEFICITS– conditions that
increase fluid loss, such as excessive perspiration,
hyperventilation, ketoacidosis, prolonged fevers, diarrhea, early-stage kidney disease, and diabetes
insipidus

Question 24

Hypotonic dehydration

Answer 24

Electrolyte loss exceeds water loss.

The clinical problems that occur result from fluid shifts between compartments, causing a decrease in plasma volume.

Fluid moves from the plasma and interstitial fluid spaces into the cells, causing a plasma volume deficit and
causing the cells to swell.

CAUSES OF FLUID VOLUME DEFICITS

a. Chronic illness
b. Excessive fluid replacement (hypotonic)
c. Kidney disease
d. Chronic malnutrition

Question 25

Fluid Volume Deficit

Answer 25

Interventions 1. Prevent further fluid losses and increase fluid compartment volumes to normal ranges. 2. Provide oral rehydration therapy if possible and IV fluid replacement if the dehydration is severe; monitor intake and output. 3. In general, isotonic dehydration is treated with isotonic fluid solutions, hypertonic dehydration with hypotonic fluid solutions, and hypotonic dehydration with hypertonic fluid solutions. 4. Administer medications, such as antidiarrheal, antimicrobial, antiemetic, and antipyretic medications, as prescribed to correct the cause and treat any symptoms. 5. Monitor electrolyte values and prepare to administer medication to treat an imbalance, if present.

Question 26

Fluid Volume Excess

Answer 26

1. Fluid intake or fluid retention exceeds the fluid needs of the body. 2. Fluid volume excess is also called overhydration or fluid overload. 3. The goal of treatment is to restore fluid balance, correct electrolyte imbalances if present, and eliminate or control the underlying cause of the overload.

Question 27

Isotonic overhydration

Answer 27

Known as HYPERVOLEMIA, ISOTONIC overhydration results from excessive fluid in the extracellular fluid compartment. Only the extracellular fluid compartment is expanded, and fluid does not shift between the extracellular and intracellular compartments. Isotonic overhydration causes CIRCULATORY OVERLOAD and interstitial edema; when severe or when it occurs in a client with poor cardiac function, heart failure and pulmonary edema can result. CAUSE: a. Inadequately controlled IV therapy b. Kidney disease c. Long-term corticosteroid therapy

Question 28

Hypertonic overhydration

Answer 28

a. The occurrence of hypertonic overhydration is rare and is caused by an excessive sodium intake. b. Fluid is drawn from the intracellular fluid compartment; the extra-cellular fluid volume expands, and the intracellular fluid volume contracts. CAUSES; a. Excessive sodium ingestion b. Rapid infusion of hypertonic saline c. Excessive sodium bicarbonate therapy

Question 29

Hypotonic overhydration

Answer 29

Hypotonic overhydration is known as WATER INTOXICATION . The excessive fluid moves into the intracellular space, and all body fluid compartments expand. Electrolyte imbalances occur as a result of dilution. CAUSES; a. Early kidney disease b. Heart failure c. Syndrome of inappropriate antidiuretic hormone secretion d. Inadequately controlled IV therapy e. Replacement of isotonic fluid loss with hypotonic fluids f. Irrigation of wounds and body cavities with hypotonic fluids A CLIENT WITH ACUTE KIDNEY INJURY, CHRONIC KIDNEY DISEASE, AND HEART FAILURE IS AT HIGH RISK FOR FLUID VOLUME EXCESS

Question 30

Fluid Volume Excess - Interventions

Answer 30

1. Prevent further fluid overload and restore normal fluid balance. 2. Administer diuretics; osmotic diuretics may be prescribed initially to prevent severe electrolyte imbalances. 3. Restrict fluid and sodium intake as prescribed. 4. Monitor intake and output; monitor weight. 5. Monitor electrolyte values and prepare to administer medication to treat an imbalance if present.

Question 31

FLUID VOLUME DEFICIT ASSESSMENTS CARDIOVASCULAR Thready, Increased Pulse Rate Decreasedd blood pressure and orthostatic (postural) hypotension Flat Neck and hand veins in dependent positions Diminished peripheral pulses Decreased central venous pressure Dysrhythmias RESPIRATORY Increased rate and depth of respirations Dyspnea NEUROMUSCULAR Decreased central nervous system activity from lethargy to coma Fever, depending on the amount of fluid loss Skeletal muscle weakness RENAL Decreased urine output INTEGUMENTARY Dry skin Poor turgor, tenting Dry mouth ``` GASTROINTESTINAL Decreased motility and diminished bowel sounds Constipation Thirst Decreased body weight ``` ``` LABORATORY FINDINGS Increased serum osmolality Increased hematocrit Increased Blood Urea Nitrogen (BUN) level Increased serum sodium level Increased urinary specific gravity ```

Answer 31

FLUID VOLUME EXCESS ASSESSMENTS ``` CARDIOVASCULAR Bounding, increased pulse rate Elevated blood pressure Distended neck and hand veins Elevated central venous pressure Dysrhythmias ``` RESPIRATORY Increased respiratory rate (shallow respirations) Dyspnea Moist crackles on auscultation ``` NEUROMUSCULAR Altered level of consciousness Headache Visual disturbances Skeletal muscle weakness Paresthesias ``` RENAL Increased urine output if kidneys can compensate; decreased urine output if kidney damage is the cause INTEGUMENTARY Pitting edema in dependent areas Pale, cool skin ``` GASTROINTESTINAL Increased motility in the GI tract Diarrhea Increased body weight Liver enlargement Ascites ``` ``` LABORATORY FINDINGS Decreased hematocrit Decreased Blood Urea Nitrogen (BUN) level Decreased serum sodium level Decreased urinary specific gravity ```

Question 32

FLUID VOLUME OVERLOAD Interventions

Answer 32

1. Prevent further fluid overload and restore normal fluid balance. 2. Administer diuretics; osmotic diuretics may be prescribed initially to prevent severe electrolyte imbalances. 3. Restrict fluid and sodium intake as prescribed. 4. Monitor intake and output; monitor weight. 5. Monitor electrolyte values and prepare to administer medication to treat an imbalance if present.

Question 33

HYPOKALEMIA 1. Hypokalemia is a serum potassium level lower than 3.5 mEq/L (3.5 mmol/L) 2. Potassium deficit is potentially life-threatening because every body system is affected Causes 1. Actual total body potassium loss a. Excessive use of medications such as diuretics or corticosteroids b. Increased secretion of aldosterone, such as in Cushing’s syndrome c. Vomiting, diarrhea d. Wound drainage, particularly gastrointestinal e. Prolonged nasogastric suction f. Excessive diaphoresis g. Kidney disease impairing reabsorption of potassium 2. Inadequate potassium intake: Fasting; nothing by mouth status 3. Movement of potassium from the extracellular fluid to the intracellular fluid a. Alkalosis b. Hyperinsulinism 4. Dilution of serum potassium a. Water intoxication b. IV therapy with potassium-deficient solutions ``` ASSESSMENTS CV Thready, weak, irregular pulse Weak peripheral pulses Orthostatic Hypotension Dysrhythmias ``` RESPIRATORY Shallow, ineffective respirations that result from profound weakness of the skeletal muscles of respiration Dimished breath sounds ``` NEUROMUSCULAR Anxiety, lethargy, confusion, coma Skeletal muscle weakness, leg cramps Loss of tactile discrimination Paresthesias Deep Tendon Hyporeflexiaa ``` GI Decreased motility, hypoactive to absent bowel sounds Nausea, vomiting, constipation, abdominal distention Paralytic Ileus LABORATORY FINDINGS Serum Potassium level lower than 3.5 mEq/L ECG: ST depression; shallow, flat, or inverted T wave, and prominent U wave INTERVENTIONS 1. Monitor electrolyte values. 2. Administer potassium supplements orally or intravenously, as prescribed. 3. Oral potassium supplements a. Oral potassium supplements may cause nausea and vomiting and should not be taken on an empty stomach; if the client complains of abdominal pain, distention, nausea, vomiting, diarrhea, or gastrointestinal bleeding, the supplement may need to be discontinued. b. Liquid potassium chloride has an unpleasant taste and should be taken with juice or another liquid. 4. Intravenously administered potassium 5. Institute safety measures for the client experiencing muscle weakness. 6. If the client is taking a potassium-losing diuretic, it may be discontinued; a potassium-sparing (retaining) diuretic may be prescribed. 7. Instruct the client about foods that are high in potassium content. POTASSIUM IS NEVER ADMINISTERED BY IV PUSH, IM OR SUBCUTANEOUS ROUTES. IV POTASSIUM IS ALWAYS DILUTED USING AN INFUSION DEVICE.

Answer 33

HYPERKALEMIA 1. Hyperkalemia is a serum potassium level that exceeds 5.0 mEq/L (5.0 mmol/L) 2. Pseudohyperkalemia: a condition that can occur due to methods of blood specimen collection and cell lysis; if an increased serum value is obtained in the absence of clinical symptoms, the specimen should be redrawn and evaluated. Causes 1. Excessive potassium intake a. Overingestion of potassium-containing foods or medications, such as potassium chloride or salt substitutes b. Rapid infusion of potassium-containing IV solutions 2. Decreased potassium excretion a. Potassium-sparing (retaining) diuretics b. Kidney disease c. Adrenal insufficiency, such as in Addison’s disease 3. Movement of potassium from the intracellular fluid to the extracellular fluid a. Tissue damage b. Acidosis c. Hyperuricemia d. Hypercatabolism ``` ASSESSMENTS CV Slow, weak, irregular heart rate Decreased blood pressure Dysrhythmias ``` RESPIRATORY Profound weakness of the skeletal muscles leading to respiratory failure NEUROMUSCULAR EARLY: Muscle twitches, cramps, paresthesias (tingling and burning followed by numbness in the hands and feet and around the mouth) LATE: Profound weakness, ascending flaccid paralysis in the arms and legs (trunk, head and respiratory muscles become affected when the serum potassium level reaches a lethal level) GI increased motility, hyperactive bowel sounds Diarrhea LABORATORY FINDINGS Serum Potassium level that exceeds 5.0 mEq/L ECG: Tall peaked T waves, flat P waves, widened QRS complexes, and prolonged PR intervals MONITOR THE CLIENT CLOSELY FOR SIGNS OF A POTASSIUM IMBALANCE. A POTASSIUM IMBALANCE CAN CAUSE CARDIAC DYSRHYTHMIAS THAT CAN BE LIFE-THREATENING, LEADING TO CARDIAC ARREST! INTERVENTIOS 1. Discontinue IV potassium (keep the IV catheter patent) and withhold oral potassium supplements. 2. Initiate a potassium-restricted diet. 3. Prepare to administer potassium-excreting diuretics if renal function is not impaired. 4. If renal function is impaired, prepare to administer sodium polystyrene sulfonate (oral or rectal route), a cation-exchange resin that promotes gastrointestinal sodium absorption and potassium excretion. 5. Prepare the client for dialysis if potassium levels are critically high. 6. Prepare for the administration of IV calcium if hyperkalemia is severe, to avert myocardial excitability. 7. Prepare for the IV administration of hypertonic glucose with regular insulin to move excess potassium into the cells. 8. When blood transfusions are prescribed for a client with a potassium imbalance, the client should receive fresh blood, if possible; transfusions of stored blood may elevate the potassium level because the breakdown of older blood cells releases potassium. 9. Teach the client to avoid foods high in potassium 10. Instruct the client to avoid the use of salt substitutes or other potassium-containing substances. 11. Monitor the serum potassium level closely when a client is receiving a potassium-sparing (retaining) diuretic.

Question 34

HYPONATREMIA 1Hyponatremia is a serum sodium level lower than 135 mEq/L (135 mmol/L). Sodium imbalances usually are associated with fluid volume imbalances. ``` CAUSES 1. Increased sodium excretion a. Excessive diaphoresis b. Diuretics c. Vomiting d. Diarrhea e. Wound drainage, especially gastrointestinal f. Kidney disease g. Decreased secretion of aldosterone ``` 2. Inadequate sodium intake a. Fasting; nothing by mouth status b. Low-salt diet 3. Dilution of serum sodium a. Excessive ingestion of hypotonic fluids or irrigation with hypotonic fluids b. Kidney disease c. Freshwater drowning d. Syndrome of inappropriate antidiuretic hormone secretion e. Hyperglycemia f. Heart failure ASSESSMENT CV Symptoms vary with changes in vascular volume NORMOVOLEMIC: Rapid pulse rate, normal blood pressure HYPOVOLEMIC: Thready, weak, rapid pulse rate; hypotension; flat neck veins' normal or low central venous pressure HYPERVOLEMIC: Rapid, bounding pulse; blood pressure normal or elevated' normal or elevated central venous pressure RESPIRATORY Shallow, ineffective respiratory movement is a late manifestations related to skeletal muscle weakness NEUROMUSCULAR Generalized skeletal muscle weakness that is worse in the extremities Diminished deep tendon reflexes ``` CNS Headache Personality changes Confusion Seizures Coma ``` GI Increased motility and hyperactive bowel sounds Nausea Abdominal cramping and diarrhea RENAL Increased urinary output INTEGUMENTARY Dry Mucous membranes LABORATORY FINDINGS Serum Sodium Level less than 135 mEq/L Decreased urinary specific gravity INTERVENTIONS: 1. If hyponatremia is accompanied by a fluid volume deficit (hypovolemia), IV sodium chloride infusions are administered to restore sodium content and fluid volume. 2. If hyponatremia is accompanied by fluid volume excess (hypervolemia), osmotic diuretics may be prescribed to promote the excretion of water rather than sodium. 3. If hyponatremia is caused by inappropriate or excessive secretion of antidiuretic hormone, medications that antagonize antidiuretic hormone may be administered. 4. Instruct the client to increase oral sodium intake as prescribed and inform the client about the foods to include in the diet. 5. If the client is taking lithium, monitor the lithium level, because hyponatremia can cause diminished lithium excretion, resulting in toxicity. HYPONATREMIA PRECIPITATES LITHIUM TOXICITY IN A CLIENT TAKING THIS MEDICATION

Answer 34

HYPERNATREMIA Hypernatremia is a serum sodium level that exceeds 145 mEq/L (145 mmol/L). CAUSES 1. Decreased sodium excretion a. Corticosteroids b. Cushing’s syndrome c. Kidney disease d. Hyperaldosteronism 2. Increased sodium intake: Excessive oral sodium ingestion or excessive administration of sodium- containing IV fluids 3. Decreased water intake: Fasting; nothing-by-mouth status 4. Increased water loss: Increased rate of metabolism, fever, hyperventilation, infection, excessive diaphoresis, watery diarrhea, diabetes insipidus ASSESSMENT CV Heart Rate and blood pressure respond to vascular volume status RESPIRATORY Pulmonary edema if hypervolemia is present NEUROMUSCULAR EARLY: Spontaneous muscle twitches; irregular muscle contractions LATE: Skeletal muscle weakness; deep tendon reflexes diminished or absent CNS Altered cerebral function is the most common manifestation of hypernatremia Normovolemic or hypovolemic: Agitation, confusion, seizures Hypervolemic: Lethary, stupor, coma GI Extreme thirst RENAL Decreased urinary output INTEGUMENTARY Dry and flushed skin Dry and sticky tongue and mucous membranes Presence or absence of edema, depending on fluid volume changes LABORATORY FINDINGS Serum Sodium Level that exceeds mEq/L Increased urinary specific gravity INTERVENTIONS 1. If the cause is fluid loss, prepare to administer IV infusions. 2. If the cause is inadequate renal excretion of sodium, prepare to administer diuretics that promote sodium loss. 3. Restrict sodium and fluid intake as prescribed.