Chapter 19: Part Two

Respiratory Alkalosis Symptoms

• Lethargy

• Light-headedness

• Confusion

• Tachycardia

• Dysrhythmias (related to hypokalemia from compensation)

• Nausea

• Vomiting

• Epigastric pain

• Tetany

• Numbness

• Tingling of extremities

• Hyperreflexia

• Seizures

• Hyperventilation (lungs are unable to compensate when there is a respiratory problem)

Metabolic Alkalosis Symptoms

• Dizziness

• Irritability

• Nervousness

• Confusion

• Tachycardia

• Dysrhythmias (related to hypokalemia from compensation)

• Anorexia

• Nausea

• Vomiting

• Tremors

• Hypertonic muscles

• Muscle cramps

• Tetany

• Tingling of fingers and toes

• Hypoventilation (compensatory action by the lungs)

PCO2 (arterial)

35-45mm Hg

Bicarbonate (HCO3 − ) level (arterial)

21-28mmol/L

PO2∗ (arterial)

80-100mm Hg

Base excess (arterial)

0 ± 2.0mmol/L

Arterial Blood Gas (Abg) Analysis

1. pH of <7.4 indicates acidosis (abnormal range below 7.35).

2. PaCO2 is low, indicating respiratory alkalosis.

3. HCO3 − level is low, indicating metabolic acidosis.

4. Metabolic acidosis matches the pH.

5. The PaCO2 level does not match the pH but is opposing the acidosis, which indicates the lungs are attempting to compensate for the metabolic acidosis.

6. The PaO2 indicates adequate oxygenation of the blood.

Rome: Mnemonic For Acid–Base Imbalances

For acid–base imbalances, the mnemonic ROME can be used.

In respiratory conditions, the pH and the PaCO2 are in opposite directions. (RO)

• In respiratory alkalosis, the pH is ↑ and the PaCO2 is ↓.• In respiratory acidosis, the pH is ↓ and the PaCO2 is ↑.

In metabolic conditions, the pH and the HCO3 − go in the same direction (equal or equivalent). (ME)•

In metabolic alkalosis, pH and HCO3 − are ↑.•

In metabolic acidosis, pH and HCO3 − are ↓.

Poor skin turgor

Fluid volume deficit

Cold, clammy skin

Na+ deficit, shift of plasma to interstitial fluid

Pitting edema

Fluid volume excess

Flushed, dry skin

Na+ excess

Bounding pulse

Fluid volume excess, shift of interstitial fluid to plasma

Rapid, weak, thready pulse

Shift of plasma to interstitial fluid, Na+ deficit, fluid volume deficit

Weak, irregular, rapid pulse

Severe K+ deficit

Weak, irregular, slow pulse

Severe K+ excess

Hypotension

Fluid volume deficit, shift of plasma to interstitial fluid, Na+ deficit

Hypertension

Fluid volume excess, shift of interstitial fluid to plasma

Deep, rapid breathing

Compensation for metabolic acidosis

Shallow, slow, irregular breathing

Compensation for metabolic alkalosis

Shortness of breath

Fluid volume excess

Moist crackles

Fluid volume excess, shift of interstitial fluid to plasma

Cramping of exercised muscle

Ca2+ deficit, Mg2+ deficit, alkalosis

Carpal spasm (Trousseau's sign)

Ca2+ deficit, Mg2+ deficit, alkalosis

Flabby muscles

K+ deficit

Positive Chvostek's sign

Ca2+ deficit, Mg2+ deficit, alkalosis

Picking at bedclothes

K+ deficit, Mg2+ deficit

Inappropriate indifference

Fluid volume deficit, Na+ deficit

Apprehension

Shift of plasma to interstitial fluid

Extreme restlessness

K+ excess, fluid volume deficit

Confusion and irritability

K+ deficit, fluid volume excess, Ca2+ excess, Mg2+ excess, H2O excess

Decreased level of consciousness

H2O excess

CVAD

central vascular access device or indwelling line

re catheters that are placed in large blood vessels (e.g., subclavian vein, jugular vein) when access to the vascular system is needed frequently. When the GI tract is nonfunctioning or requires rest, CVADs are used to deliver nutrients and electrolytes.

In contrast to CVADs, the basic IV catheter is inserted into a peripheral vein in the hand, inside of the arm, or antecubital fossa and is used for short-term IV access.

Central venous access can be achieved by three different methods: centrally inserted catheters, peripherally inserted central catheters (PICCs), or implanted ports.

Centrally inserted catheters and implanted ports must be placed by a physician, whereas PICCs can be inserted by a nurse with specialized training.

CVADs enable frequent, continuous, rapid, or intermittent administration of fluids and medications. They allow for the administration of drugs that are potential vesicants, blood and blood products, and parenteral nutrition. They may also be used for hemodynamic monitoring and venous blood sampling. These devices are indicated for patients who have limited peripheral vascular access or who have a projected need for long-term vascular access.

Advantages of CVADS

include a reduced need for multiple venipunctures, decreased risk of extravasation injury, and immediate access to the central venous system.

Although the incidence is decreased, extravasation can nonetheless occur if the device being used is displaced or damaged

Disadvantages of CVADS

are an increased risk of systemic infection and the invasiveness of the insertion procedure.

Dextrose in Water

5%

Isotonic, but physiologically hypotonic

278 mmol/Kg, 50 g/L glucose

Provides free water necessary for renal excretion of solutes

Used to replace water losses and treat hypernatremia

Provides 170 cal/L

Does not provide any electrolytes

10%

hypertonic

556 mmol/kg, 100 g/l glucose

Provides free water only, no electrolytes

Provides 340 cal/L

Saline (Sodium Chloride [NaCl])

0.45%

Hypotonic

154 mmol/L, 0 g/l glucose

Provides free water in addition to Na+ and Cl Used to replace hypotonic fluid losses

Used as maintenance solution, although it does not replace daily losses of other electrolytes

Provides no calories

0.9%

isotonic

308 mmol/L, 0g/L

Used to expand intravascular volume and replace extracellular fluid losses

Only solution that may be administered with blood products

Contains Na+ and Cl − in excess of plasma levels

Does not provide free water, calories, other electrolytes

May cause intravascular overload or hyperchloremic acidosis

3.0%

hypertonic

1026 mmol/L, 0g/l

Used to treat symptomatic hyponatremia

Must be administered slowly and with extreme caution because it may cause dangerous intravascular volume overload and pulmonary edema

Dextrose in Saline

5% in 0.225%

Isotonic

355 mmol/L, 50 g/L

Provides Na+, Cl − , and free water

Used to replace hypotonic losses and treat hypernatremia

Provides 170 cal/L

5% in 0.45%

Hypertonic

432 mmol/L, 50 g/L

Same as 0.45% NaCl except provides 170 cal/L

5% in 0.9%

Hypertonic

586 mmol/L, 50 g/L

Same as 0.9% NaCl except provides 170 cal/L

Multiple-Electrolyte Solutions

Ringer's solution

Isotonic

309 mmol, L 0 g/L

Similar in composition to plasma except that it has excess Cl − , no Mg2+, and no HCO3 −

Does not provide free water or calories

Used to expand the intravascular volume and replace extracellular fluid losses

Lactated Ringer's (Hartmann's) solution

Isotonic

274 mmol, L 0 g/L

Similar in composition to normal plasma except does not contain Mg2+

Used to treat losses from burns and lower GI tract

May be used to treat mild metabolic acidosis but should not be used to treat lactic acidosis

Does not provide free water or calories

1. Why are older persons more at risk for fluid related imbalances?

a. A higher proportion of their fluid is stored intracellularly.

b. They have an increase in lean body mass as they age.

c. They have a larger portion of fluid extracellularly which is easily lost.

d. They have less total body fluid because of a decline in muscle and increase in fat.

d. They have less total body fluid because of a decline in muscle and increase in fat.

2. If a client's extracellular fluid space is hypertonic in comparison to their intracellular fluid compartment, what would occur?

a. Diffusion of fluid into the cell

b. Osmotic pull of fluid out of the cell

c. Active transport of sodium out of the cell

d. Facilitated diffusion of glucose into the cell

b. Osmotic pull of fluid out of the cell

3a. A client was admitted to the medical unit with GI bleeding and fluid volume deficit. What are the clinical manifestations of the latter problem? (Select all that apply.)

a. Weight loss

b. Dry oral mucosa

c. Full bounding pulse

d. Engorged neck veins

e. Decreased central venous pressure

a. Weight loss

b. Dry oral mucosa

e. Decreased central venous pressure

3b. Which of the following nursing actions is required for clients with hyponatremia?

a. Fluid restriction

b. Administration of hypotonic intravenous fluids

c. Administration of a cation exchange resin

d. Increased water intake for clients on nasogastric suction

a. Fluid restriction

3c. Which of the following should the nurse monitor for when a client is receiving a loop diuretic?

a. Restlessness and agitation

b. Paresthesias and irritability

c. Weak, irregular pulse and poor muscle tone

d. Increased blood pressure and muscle spasms

c. Weak, irregular pulse and poor muscle tone

3d. Which of the following clients would be at greatest risk for the potential development of hypermagnesemia?

a. An 83-year-old man with lung cancer and hypertension

b. A 65-year-old woman with hypertension taking β-adrenergic blockers

c. A 42-year-old woman with systemic lupus erythematosus and renal failure

d. A 50-year-old man with benign prostatic hyperplasia and a urinary tract infection

c. A 42-year-old woman with systemic lupus erythematosus and renal failure

3e. In a client who has just undergone a total thyroidectomy, it is especially important for the nurse to assess which of the following?

a. Weight gain

b. Depressed reflexes

c. Positive Chvostek's sign

d. Confusion and personality changes

c. Positive Chvostek's sign

3f. Care of the client experiencing hyperphosphatemia secondary to renal failure includes which of the following?

a. Calcium supplements

b. Potassium supplements

c. Magnesium supplements

d. Fluid replacement therapy

a. Calcium supplements

4. How do the lungs act as an acid-base buffer?

a. By increasing respiratory rate and depth when CO2 levels in the blood are high, thereby reducing acid load

b. By increasing respiratory rate and depth when CO2 levels in the blood are low, thereby reducing base load

c. By decreasing respiratory rate and depth when CO2 levels in the blood are high, thereby reducing acid load

d. By decreasing respiratory rate and depth when CO2 levels in the blood are low, thereby increasing acid load

a. By increasing respiratory rate and depth when CO2 levels in the blood are high, thereby reducing acid load

5. A client has the following arterial blood gas results: pH, 7.52; partial pressure of carbon dioxide in the arterial blood (PaCO2), 30 mm Hg; HCO3 − level, 24 mmol/L. These results indicate the presence of which acid-base disturbance?

a. Metabolic acidosis

b. Metabolic alkalosis

c. Respiratory acidosis

d. Respiratory alkalosis

d. Respiratory alkalosis

6. What is the typical fluid replacement for the client with a fluid volume deficit?

a. Dextran

b. 0.45% Saline

c. Lactated Ringer's solution

d. 5% Dextrose in 0.45% saline

c. Lactated Ringer's solution

7. The nurse is unable to flush a central venous access device and suspects occlusion. Which of the following would be the best nursing intervention?

a. Apply warm moist compresses to the insertion site.

b. Attempt to force 10 mL of normal saline into the device.

c. Place the client on the left side with head-down position.

d. Instruct the client to change positions, raise arm, and cough.

d. Instruct the client to change positions, raise arm, and cough.