Fluid and Electrolyte Balance - UNIT 3

What factors can effect body fluid?

- Age - Gender (hormonal fluctuations in women can cause fluid retention. Men have higher total body water percentage. ) - Fat cell percentage (↑fat = ↓ water)

Isotonic over hydration (Hypervolemia)

- Excess of both sodium and water - Increase in circulating blood volume while serum osmolarity stays the same - Causes: Heart failure Renal failure Cirrhosis

Hypotonic overhydration (water intoxication)

- Excess of water causes dilutional deficiency of electrolytes - Increase in circulating blood volume with a decrease in serum osmolarity - Fluid moves into cells, causing cellular swelling which can lead to pulmonary congestion and cerebral edema - Causes: Excessive intake of salt-free solutions - water Prolonged use of hypotonic IV solutions SIADH (Syndrome of inappropriate antidiuretic hormone secretion)

fluid volume deficit

- Excess water and/or sodium loss - Inadequate water and/or sodium intake - Fluid shifts from bloodstream to interstitial space Isotonic dehydration Hypertonic dehydration urine specific gravity >1.030 Increased hematocrit BUN >20

fluid volume excess

- Excessive fluid intake - Abnormal fluid retention (disease, medications) - Long-term corticosteroid therapy - Adrenal gland disorders Isotonic overhydration (hypervolemia) Hypotonic over hydration (water intoxication) Urine specific gravity <1.005 Decreased hematocrit BUN <7

Nursing care of patients with overhydration includes:

- Observe respiratory rate, symmetry, and effort. - Auscultate breath sounds in all lung fields. Lung sounds can be diminished with crackles. - Monitor for shortness of breath and dyspnea. - Check ABGS, SaO2, CBC, and chest x-ray results. - Position the client in semi-Fowler's position. • Measure the client's weight daily at same time of day using the same scale. • Monitor and document edema (pretibial, sacral, periorbital). • Monitor I&O. - Implement prescribed restrictions for fluid and sodium intake. - Provide fluids in small glass to promote the perception of a full glass of fluid. • Administer supplemental oxygen as needed. Reduce IV flow rates. - Reposition the client at least every 2 hr. • Monitor and document circulation to the extremities. • Administer diuretics (osmotic, loop) as prescribed. - Support arms and legs to decrease dependent edema.

ANP (atrial natriuretic peptide)

- Produced and stored in the atrium of the heart. - Stops the action of RAAS (causes vasodilation and increasing excretion of sodium and water.)

ADH (antidiuretic hormone/vasopressin)

- Produced by hypothalamus. - Secreted by posterior pituitary. - ADH stimulates re-absorption of water within the nephron and constriction of vessels (raising blood pressure). - increases water retention if serum osmolality increases or blood volume decreases. - too much ADH = too much water in the vascular space *RETAIN

What do electrolytes do?

- Regulate water distribution - Govern acid-base balance - Transmit nerve impulses - Contribute to energy generation and blood clotting

How is thirst regulated and stimulated?

- Regulated by the hypothalamus - Stimulated by increase in extracellular fluid osmolality and drying of mucous membranes

Hypotonic IV fluids

- from the extracellular space (vessel) into cell Uses: rehydration without increasing blood pressure; useful in clients with renal, cardiac disease Caution in: clients with liver disease, shock, trauma, and burns Monitor for: Fluid volume deficit, worsening hypovolemia due to decreased vascular volume, cerebral edema Examples: 0.33% NS, .45% NS, and .225% NS

Isotonic IV fluids

- stays in the vascular space Uses: replacing fluid losses from vomiting, sweating, trauma, burns, etc. Caution: clients with heart and renal disease, no LR for clients with liver disease Monitor for: edema and fluid volume excess Examples: 0.9% NS, LR, D5W, D5 1/2NS

Hypertonic IV solutions

-from cell into extracellular space (vessel) Uses: Increase serum osmolality and corrects severe hyponatremia Caution: monitor closely, use an IV pump, cardiac disease, renal disease, dehydration, and diabetic ketoacidosis Monitor for: Pulmonary edema, flood volume excess Examples: D5 1/2 NS, D5 NS, D5 LR, 3% NS, and D50W

Regulation of fluid balance

1. Kidneys 2. Hormones (ADH, RAAS, ANP) 3. Thirst

Magnesium (Mg+) normal range

1.3-2.1 mEq/L

Sodium (Na+) normal range

135-145 mEq/L

Daily I&O is approximately ______ ml/day

2,000-3,000

Phosphate (PO-) normal range

3.0-4.5 mg/dL

Potassium (K+) normal range

3.5-5.0 mEq/L

Normal blood pH range

7.35-7.45

Calcium (Ca+) normal range

9-10.5 mg/dL

Chloride (Cl) normal range

96-106 mEq/L

List some factors that can affect acid-base balance:

Age (infants kidneys not developed have higher metabolic rate creating more toxins -- older adults have decreased thirst sensation) stress (aldosterone production causes ECF retention) surgery (fluid loss, NPO) weight (obese = fluids are disproportionate) medical disorder ( kidney, liver, cardiovascular failure)

9. Which activity is important to include in the plan of care for a client with a peripherally inserted central catheter (PICC)? a. Use sterile technique when changing the PICC dressing. b. Change the IV tubing every 72 hours. c. Take blood pressure in the arm with the PICC line. d. Use only macrodrip tubing with IV infusions through the PICC line.

Answer: a Because a PICC enters the body through a peripheral vein and is threaded up to the superior vena cava, resting just outside the right atrium of the heart, strict sterile technique is used during insertion and care of PICCs to prevent entrance of bacteria into the line. PICC tubing is usually changed every 24 hours. Never take blood pressure in an arm with a PICC. Macrodrip or microdrip tubing can be used for infusions through a PICC.

2. A nurse caring for a hospitalized patient with diarrhea and dehydration is told in the shift report that the patient's laboratory results have just come in. Which abnormal laboratory values should be reported to the primary care provider? (Select all that apply). a. Sodium (Na) level 150 mEq/L b. Potassium (K) level 3.3 mEq/L c. Calcium (Ca) level 9.5 mg/dL d. Magnesium (Mg) level 1.0 mEq/L e. Chloride (Cl) level 101 mEq/L

Answer: a, b, and d The sodium, potassium, and magnesium levels are all abnormal levels that often can be seen in dehydrated clients with prolonged diarrhea. Normal sodium levels for adults range from 135 to 145 mEq/L. Normal potassium levels for adults range from 3.5 to 5 mEq/L. Normal magnesium levels for adults range from 1.3 to 2.1 mEq/L. The calcium and chloride values are within normal limits.

5. A nurse in the emergency department is caring for an adult patient with numerous draining wounds from gunshots. The patient's pulse rate has increased from 100 to 130 beats/min over the past hour, and the patient experiencing orthostatic hypotension. For which imbalance should the nurse assess? a. Respiratory acidosis b. Extracellular fluid volume deficit c. Metabolic alkalosis d. Intracellular fluid volume excess

Answer: b The draining wounds indicate hypovolemia, or extracellular fluid volume deficit. As circulating blood volume decreases, the heart rate increases to maintain normal cardiac output, and the patient may experience orthostatic hypotension and lightheadedness with position changes. Respiratory acidosis and metabolic alkalosis do not have as a symptom a rapidly increasing pulse rate. Intracellular fluid volume excess causes pulmonary congestion and cerebral edema.

8. The nurse is assessing the intravenous (IV) site in the right forearm and notices the area about 1 inch around it is cool, swollen, firm, and tender to touch. Which action should the nurse take first? a. Take patient's temperature b. Apply an ice pack to site c. Stop infusion and remove IV catheter d. Call the primary care provider immediately

Answer: c The area around an IV infiltration is cool, swollen, firm, and tender to touch. The first intervention to take for an infiltrated IV is to stop the infusion and discontinue the IV by removing the catheter. Applying cold compresses may be appropriate for hyperosmolar fluids, but only after the IV infusion has been stopped. Taking the temperature would be an assessment to make if the complication of infection is suspected. The primary care provider does not need to be notified unless grade 3 or 4 infiltrations are noted (>6 inches edema).

4. The nurse is caring for a patient with hypocalcemia who does not like milk. Which food should the nurse encourage the patient to consume? a. Cod b. Eggs c. Spinach d. Tomatoes

Answer: c Dark leafy vegetables such as spinach, kale, turnip greens, broccoli, Brussels sprouts, and cabbage are sources high in calcium

LA patient has reported a 2-kg (4.4-lb) weight gain over the past 3 days. Which dietary factor should the nurse assess? a. Protein intake b. Potassium intake c. Calorie intake d. Sodium intake

Answer: d A weight gain of 2 kg in 3 days suggests fluid retention. Increased sodium intake leads to increased fluid retention. Although it is important to ask the patient about intake of all nutrients, the other options cannot cause this much weight gain in 3 days.

10. The nurse has just begun an infusion of packed red blood cells (PRBC). Which of the following changes would indicate a transfusion reaction and warrants stopping the infusion? a. Respirations increased from 16/min to 20/min. b. Urine output in Foley catheter bag has 50 mL/h output of dark yellow urine.ogd c. Heart rate decreased from 77 beats/min to 62 beats/ min. d. Temperature increased from 100° degrees to 102.2° F

Answer: d An increased temperature of more than 2 degrees Fahrenheit indicates a febrile nonhemolytic reaction, and the infusion should be stopped. The primary care provider and blood bank should be notified. The urine output is an adequate hourly amount. The heart rate is normal. The respiratory rate is not a significant change.

7. A patient with a continuous IV of D, 0.9% NS running at 150 mL/hr begins to exhibit hallucinations and confu- sion. Which laboratory value should the nurse expect to check? a. Calcium b. Carbon dioxide c. Magnesium d. Sodium

Answer: d Hypernatremia can be caused by hypertonic IV solutions such as D5 0.9% NS. Symptoms of severe hypernatremia include confusion, irritability, decreased level of consciousness, hallucinations, and seizures.

6. A 65-year-old female patient is a two-pack-a-day cigarette smoker with a history of chronic obstructive pulmonary disease (COPD). What is the interpretation of her arterial blood gas values (pH 7.34, PCO, 55, PO, 82, HCO, 32)? a. Partially compensated respiratory alkalosis b. Uncompensated metabolic acidosis c. Uncompensated respiratory alkalosis d. Partially compensated respiratory acidosis

Answer: d Patients with COPD tend to have chronic carbon dioxide retention. The patient is slightly acidotic (i.e., arterial pH below 7.35) with a higher than normal partial pressure of carbon dioxide (PCO2), which is inverse and therefore a respiratory issue. The compensatory response to respiratory acidosis is buffering, as indicated by the higher than normal bicarbonate (HCO3−) level. The increase in bicarbonate only partially shifts the pH toward normal, but partial compensation prevents the acid-base imbalance from becoming life-threatening. The kidneys will continue to compensate in an attempt to bring the pH into the normal range.

3. For a patient with a nursing diagnosis of Dehydration, the nurse is alert to which signs and symptoms? (Select all that apply). a. Hypertension b. Flushed skin c. Dry mucous membranes d. Weak, thready pulse e. Pale yellow urine

Answers: b, c, d Depending on the severity of fluid volume deficit, the patient may have hypotension. The skin is flushed and dry, the mucous membranes are dry, and the pulse is weak and thready. Hypertension occurs with fluid volume overload. For patients with fluid volume deficit, the urine is dark yellow and concentrated.

Review how fluids move through the body:

Fluids move throughout the body by going back and forth across a cell's semipermeable membrane. Diffusion: molecules move from an area of higher concentration to an area of low concentration. Facilitated diffusion: involves the use of protein carrier in the cell membrane. Osmosis: is the movement of water down a concentration gradient, from a region of low solute concentration to one of high solute concentration. Hydrostatic Pressure: is the force of fluid in a compartment pushing against a cell membrane or vessel wall. Oncotic Pressure: is the osmotic pressure caused by plasma colloids in solution. Active Transport: is a process in which molecules move against the concentration gradient.

Describe the distribution of fluids in the body...

Intracellular (fluid inside the cell) = 2/3 body water found within cells/40% of body weight Extracellular (fluid outside the cell)= 1/3 body water found outside of the cells. 1. Interstitial (around the cells) = 25% accounted for total body fluid (excess =2/3 ECF) 2. Intravascular (in the blood vessels, plasma) = 8% of body fluid 3. Transcellular (cerebral spinal, synovial, peritoneal, pleural, and pericardial fluid)

What is important to know concerning weight as a measure of fluid loss/gain?

Measure weight at the same time, clothes and scale 1 kg (2.2 lb) = 1 L of fluid 5% loss = clinically significant 8% loss = severe 15% loss = fatal

The nurse must _____ administer IV potassium as a push bolus medication because it can cause severe cardiac arrhythmias and death.

NEVER

who is ultimately responsible for assessing the patient and evaluating IV therapy?

RN

hypertonic solution

Solute concentration is greater than that inside the cell; cell loses water

hypotonic solution

Solute concentration is less than that inside the cell; cell gains water

Thyroid Hormone (TH)

The major hormone secreted by thyroid follicles; stimulates enzymes concerned with glucose oxidation. ^ TH = ^ cardiac output = ^ urine output

Expected findings of dehydration include:

VITAL SIGNS: Hypothermia (hypovolemia) or hyperthermia (dehydration), tachycardia, thready pulse, hypotension, orthostatic hypotension, decreased central venous pressure, tachypnea (increased respirations), hypoxia NEUROMUSCULOSKELETAL: Dizziness, syncope, confusion, weakness, fatigue; seizures (rapid/severe dehydration) GI: Thirst, dry mucous membranes, dry furrowed tongue, nausea, vomiting, anorexia, acute weight loss RENAL: Oliguria (decreased production of urine) OTHER FINDINGS: Diminished capillary refill, cool clammy skin, diaphoresis, sunken eyeballs, flattened neck veins, absence of tears, decreased skin turgor

Expected findings of iverhydration includes:

VITAL SIGNS: Tachycardia, bounding pulse, hypertension, tachypnea, increased central venous pressure NEUROMUSCULOSKELETAL: Confusion, muscle weakness, altered level of consciousness, paresthesias, visual changes; seizures (if severe, sudden hyponatremia/water excess). GI: Increased motility, ascites RESPIRATORY: Dyspnea, orthopnea, crackles OTHER FINDINGS: Pitting edema, distended neck veins, weight gain, skin pallor and cool to touch

Isotonic dehydration

WATER LOSS = ELECTROLYTE LOSS MOST COMMON TYPE of dehydration!!!!!!!!!!! - Water and sodium are lost at the same rate - Circulating volume decreases but serum osmolarity remain unchanged - Causes: Hemorrhage Burns Vomiting Diarrhea Addison disease Fever Excessive perspiration

Hypertonic dehydration

WATER LOSS EXCEEDS ELECTROLYTE LOSS - Loss of more water than salt - Can be serious if not recognized and treated. - Water pulled out of the cells, into the ECF - Circulating fluid volume decreases and serum osmolarity increases - Causes: Diabetes insipidus Diabetic ketoacidosis Administration of osmotic diuretics Hypertonic enteral tube feedings or hypertonic intravenous fluids Prolonged vomiting and diarrhea

relative dehydration is

a shift of water from the plasma (blood) to the interstitial space

Fluid overload

an excess of fluid or water (with water intoxication). This includes hemodilution, which makes the amount of blood components (blood cells, electrolytes) seem lowet.

when the pH increases above normal (alkaline), the lungs conserve carbon dioxide by ______________________________.

decreasing the rate and depth of respirations

When the body is too acidic (<7.35), the kidneys __________ and __________.

excrete more hydrogen ions; retain bicarbonate

RAAS (renin-angiotensin-aldosterone system)

in response to decreased blood flow (↓ BP): kidneys secrete renin > angiotensin 1 (lungs) > angiotensin II (liver) > production of aldosterone (kidneys) = retention of water and sodium

When the pH falls below normal (acidic), the lungs exhale more carbon dioxide by _____________________________.

increasing the rate and depth of respirations.

Hypervolemia or fluid volume excess

involves and excess of water and electrolytes, so that the two are still in the right proportions. i.e.: excessive sodium intake causes the body to retain water, so that there is too much of both

hypovolemia (isotonic dehydration/fluid volume deficit)

lack of both water and electrolytes, causing a decrease in circulating blood volume

actual dehydration is

lack of fluid in the body

colloids

larger molecules that do not dissolve readily (proteins)

Severe FVE can lead to _____ and _____

pulmonary edema and heart failure.

When the pH is abnormally alkaline (>7.45) the kidneys __________ and __________.

retain hydrogen ions; excrete bicarbonate ions

Isotonic

same tonicity as the blood (happy cells)

Rapid or severe dehydration can cause _____.

seizures

crystalloids

solutes that readily dissolve (electrolytes)

______ is the primary measure of fluid loss/gain

weight

Nursing care of patients with dehydration includes:

• Monitor respiratory rate, effort, and oxygen saturation (Sa02). • Check urinalysis, CBC, and electrolytes. • Administer supplemental oxygen as prescribed. • Measure the client's weight daily at same time of day using the same scale. • Observe for nausea and vomiting. • Assess postural blood pressure and pulse. (Check for hypotension and orthostatic hypotension.) • Check neurologic status to determine level of consciousness. • Assess heart rhythm. • Initiate and maintain IV access. • Provide oral and IV rehydration therapy as prescribed. • Monitor I&O. Encourage fluids as tolerated. Alert the provider to a urine output less than 30 mL/hr. • Monitor level of consciousness and ensure client safety. • Observe level of gait stability. Encourage the client to use the call light and ask for assistance. • Encourage the client to change positions slowly (rolling from side to side or standing up).