Ch 13 Fluid & Electrolytes prep u

A nurse can estimate serum osmolality at the bedside by using a formula. A patient who has a serum sodium level of 140 mEq/L would have a serum osmolality of:

280 mOsm/kg. Serum osmolality can be estimated by doubling the serum sodium or using the formula: Na × 2 = glucose/18 + BUN/3. Therefore, the nurse could estimate a serum osmolality of 280 mOsm/kg by doubling the serum sodium value of 140 mEq/L.

The health care provider ordered an IV solution for a dehydrated patient with a head injury. Select the IV solution that the nurse knows would be contraindicated.

5% DW A solution of D5W is an isotonic IV solution that is contraindicated in head injury because it may increase intracranial pressure.

A patient complains of tingling in the fingers as well as feeling depressed. The nurse assesses positive Trousseau's and Chvostek's signs. Which decreased laboratory results does the nurse observe when the patient's laboratory work has returned?

Calcium

Air embolism is a potential complication of IV therapy. The nurse should be alert to which clinical manifestation associated with air embolism?

Chest pain

The physician has prescribed 0.9% sodium chloride IV for a hospitalized client in metabolic alkalosis. Which nursing actions are required to manage this client? Select all that apply.

Compare ABG findings with previous results. Maintain intake and output records. Document presenting signs and symptoms.

You are caring for a 72-year-old client who has been admitted to your unit for a fluid volume imbalance. You know which of the following is the most common fluid imbalance in older adults?

Dehydration

A nurse is caring for an adult client with numerous draining wounds from gunshots. The client's pulse rate has increased from 100 to 130 beats per minute over the last hour. The nurse should further assess the client for which of the following?

Extracellular fluid volume deficit Fluid volume deficit (FVD) occurs when the loss extracellular fluid (ECF) volume exceeds the intake of fluid. FVD results from loss of body fluids and occurs more rapidly when coupled with decreased fluid intake. A cause of this loss is hemorrhage.

What foods can the nurse recommend for the patient with hypokalemia?

Fruits such as bananas and apricots Sources of potassium include fruit juices and bananas, melon, citrus fruits, fresh and frozen vegetables, lean meats, milk, and whole grains

You are caring for a new client on your unit who is third-spacing fluid. You know to assess for what type of edema?

Generalized

Which intervention is most appropriate for a client with an arterial blood gas (ABG) of pH 7.5, a partial pressure of arterial carbon dioxide (PaCO2) of 26 mm Hg, oxygen (O2) saturation of 96%, bicarbonate (HCO3-) of 24 mEq/L, and a PaO2 of 94 mm Hg?

Instruct the client to breathe into a paper bag. The ABG results reveal respiratory alkalosis. The best intervention to raise the PaCO2 level would be to have the client breathe into a paper bag.

Your client has a diagnosis of hypervolemia. What would be an important intervention that you would initiate?

Limit sodium and water intake.

The nurse is caring for a patient with diabetes type I who is having severe vomiting and diarrhea. What condition that exhibits blood values with a low pH and a low plasma bicarbonate concentration should the nurse assess for?

Metabolic acidosis

The calcium concentration in the blood is regulated by which mechanism?

Parathyroid hormone (PTH)

Which electrolyte is a major cation in body fluid?

Potassium

A client with a suspected overdose of an unknown drug is admitted to the emergency department. Arterial blood gas values indicate respiratory acidosis. What should the nurse do first?

Prepare to assist with ventilation. Respiratory acidosis is associated with hypoventilation; in this client, hypoventilation suggests intake of a drug that has suppressed the brain's respiratory center. Therefore, the nurse should assume the client has respiratory depression and should prepare to assist with ventilation. After the client's respiratory function has been stabilized, the nurse can safely monitor the heart rhythm, prepare for gastric lavage, and obtain a urine specimen for drug screening.

Which of the following arterial blood gas results would be consistent with metabolic alkalosis?

Serum bicarbonate of 28 mEq/L Evaluation of arterial blood gases reveals a pH greater than 7.45 and a serum bicarbonate concentration greater than 26 mEq/L.

A patient with diabetes insipidus presents to the emergency room for treatment of dehydration. The nurse knows to review serum laboratory results for which of the diagnostic indicators?

Sodium level of 150 mEq/L Hypernatremia (normal serum sodium is 135 to 145 mEq/L) is consistent with increased fluid loss and dehydration in diabetes insipidus.

To compensate for decreased fluid volume (hypovolemia), the nurse can anticipate which response by the body?

Tachycardia

A client admitted with acute anxiety has the following arterial blood gas (ABG) values: pH, 7.55; partial pressure of arterial oxygen (PaO2), 90 mm Hg; partial pressure of arterial carbon dioxide (PaCO2), 27 mm Hg; and bicarbonate (HCO3-), 24 mEq/L. Based on these values, the nurse suspects:

respiratory alkalosis. This client's above-normal pH value indicates alkalosis. The below-normal PaCO2 value indicates acid loss via hyperventilation; this type of acid loss occurs only in respiratory alkalosis.

The nurse is caring for four clients on a medical unit. The nurse is most correct to review which client's laboratory reports first for an electrolyte imbalance?

A 52-year-old with diarrhea Electrolyte deficiency occurs from an inadequate intake of food, conditions that deplete water such as nausea and vomiting, or disease processes that cause an excess of electrolyte amounts.

The nurse is correct to state that a client's body needs to have adequate nutrition to maintain energy. Which type of transport of dissolved substances requires adenosine triphosphate (ATP)?

Active transport

To evaluate a client for hypoxia, the physician is most likely to order which laboratory test?

Arterial blood gas (ABG) analysis

Which findings indicate that a client has developed water intoxication secondary to treatment for diabetes insipidus?

Confusion and seizures Classic signs of water intoxication include confusion and seizures, both of which are caused by cerebral edema. Weight gain will also occur. Sunken eyeballs, thirst, and increased BUN levels indicate fluid volume deficit. Spasticity, flaccidity, and tetany are unrelated to water intoxication.

Oral intake is controlled by the thirst center, located in which of the following cerebral areas?

Hypothalamus

Which is considered an isotonic solution?

0.9% normal saline An isotonic solution is 0.9% normal saline (NaCl). Dextran in normal saline is a colloid solution, 0.45% normal saline is a hypotonic solution, and 3% NaCl is a hypertonic solution.

A 54-year-old male patient is admitted to the hospital with a case of severe dehydration. The nurse reviews the patient's laboratory results. Which of the following results are consistent with the diagnosis? Select all that apply.

Blood urea nitrogen (BUN) of 23 mg/dL Serum osmolality of 310 mOsm/kg Serum sodium of 148 mEq/L Urine specific gravity of 1.03

The nurse is caring for a client in heart failure with signs of hypervolemia. Which vital sign is indicative of the disease process?

Elevated blood pressure Indicative of hypervolemia is a bounding pulse and elevated blood pressure due to the excess volume in the system. Respirations are not typically affected unless there is fluid accumulation in the lungs. Temperature is not generally affected.

A nurse is caring for a client with metastatic breast cancer who is extremely lethargic and very slow to respond to stimuli. The laboratory report indicates a serum calcium level of 12.0 mg/dl, a serum potassium level of 3.9 mEq/L, a serum chloride level of 101 mEq/L, and a serum sodium level of 140 mEq/L. Based on this information, the nurse determines that the client's symptoms are most likely associated with which electrolyte imbalance?

Hypercalcemia The normal reference range for serum calcium is 8.6 to 10.2 mg/dl. A serum calcium level of 12 mg/dl clearly indicates hypercalcemia.

A client has the following arterial blood gas (ABG) values: pH, 7.12; partial pressure of arterial carbon dioxide (PaCO2), 40 mm Hg; and bicarbonate (HCO3-), 15 mEq/L. These ABG values suggest which disorder?

Metabolic acidosis This client's pH value is below normal, indicating acidosis. The HCO3- value also is below normal, reflecting an overwhelming accumulation of acids or excessive loss of base, which suggests metabolic acidosis. The PaCO2 value is normal, indicating absence of respiratory compensation. These ABG values eliminate respiratory alkalosis, respiratory acidosis, and metabolic alkalosis.

The client's lab values are sodium 166 mEq/L, potassium 5.0 mEq/L, chloride 115 mEq/L, and bicarbonate 35 mEq/L. What condition is this client likely to have, judging by anion gap?

Metabolic acidosis The anion gap is the difference between sodium and potassium cations and the sum of chloride and bicarbonate anions. An anion gap that exceeds 16 mEq/L indicates metabolic acidosis. In this case, the anion gap is (166 + 5) − (115 + 35), yielding 21 mEq/L, which suggests metabolic acidosis.

A client in the emergency department reports that he has been vomiting excessively for the past 2 days. His arterial blood gas analysis shows a pH of 7.50, partial pressure of arterial carbon dioxide (PaCO2) of 43 mm Hg, partial pressure of arterial oxygen (PaO2) of 75 mm Hg, and bicarbonate (HCO3-) of 42 mEq/L. Based on these findings, the nurse documents that the client is experiencing which type of acid-base imbalance?

Metabolic alkalosis A pH over 7.45 with a HCO3- level over 26 mEq/L indicates metabolic alkalosis. Metabolic alkalosis is always secondary to an underlying cause and is marked by decreased amounts of acid or increased amounts of base HCO3-. The client isn't experiencing respiratory alkalosis because the PaCO2 is normal. The client isn't experiencing respiratory or metabolic acidosis because the pH is greater than 7.35.

The nurse on a surgical unit is caring for a client recovering from recent surgery with the placement of a nasogastric tube to low continuous suction Which acid-base imbalance is most likely to occur?

Metabolic alkalosis Metabolic alkalosis results in increased plasma pH because of an accumulated base bicarbonate or decreased hydrogen ion concentration. Factors that increase base bicarbonate include excessive oral or parenteral use of bicarbonate-containing drugs, a rapid decrease in extracellular fluid volume and loss of hydrogen and chloride ions as with gastric suctioning. Acidotic states are from excess carbonic acid and hydrogen ions in the system. Respiratory alkalosis results from a carbonic acid deficit that occurs when rapid breathing releases more CO2 than necessary.

A client is being treated in the ICU 24 hours after having a radical neck dissection completed. The client's serum calcium concentration is 7.6 mg/dL (1.9 mmol/L). Which physical examination finding is consistent with this electrolyte imbalance?

Presence of Trousseau sign After radical neck resection, a client is prone to developing hypocalcemia. Hypocalcemia is defined as a serum value <8.6 mg/dL (<2.15 mmol/L). Signs and symptoms of hypocalcemia include Chvostek sign, which consists of muscle twitching enervated by the facial nerve when the region that is about 2 cm anterior to the earlobe, just below the zygomatic arch, is tapped; and a positive Trousseau sign can be elicited by inflating a blood pressure cuff on the upper arm to about 20 mm Hg above systolic pressure; within 2 to 5 minutes, carpal spasm (an adducted thumb, flexed wrist and metacarpophalangeal joints, and extended interphalangeal joints with fingers together) will occur as ischemia of the ulnar nerve develops.

A client with an intravenous infusion is rubbing his arm. The nurse assesses the site and decides to discontinue the current infusion because of concern that the client has developed phlebitis. Which of the following clinical manifestations would the nurse assess with phlebitis? Select all that apply.

Reddened area along the path of the vein Tender area around the insertion site if indications lead to suspected phlebitis, the nurse will discontinue the intravenous line and restart with a different vessel.

A nurse reviews the arterial blood gas (ABG) values of a client admitted with pneumonia: pH, 7.51; PaCO2, 28 mm Hg; PaO2, 70 mm Hg; and HCO3--, 24 mEq/L. What do these values indicate?

Respiratory alkalosis A client with pneumonia may hyperventilate in an effort to increase oxygen intake. Hyperventilation leads to excess carbon dioxide (CO2) loss, which causes alkalosis — indicated by this client's elevated pH value. With respiratory alkalosis, the kidneys' bicarbonate (HCO3-) response is delayed, so the client's HCO3- level remains normal. The below-normal value for the partial pressure of arterial carbon dioxide (PaCO2) indicates CO2 loss and signals a respiratory component. Because the HCO3- level is normal, this imbalance has no metabolic component. Therefore, the client is experiencing respiratory alkalosis.

A client is diagnosed with syndrome of inappropriate antidiuretic hormone (SIADH). The nurse should anticipate which laboratory test result?

Serum sodium level of 124 mEq/L In SIADH, the posterior pituitary gland produces excess antidiuretic hormone (vasopressin), which decreases water excretion by the kidneys. This, in turn, reduces the serum sodium level, causing hyponatremia, as indicated by a serum sodium level of 124 mEq/L. In SIADH, the serum creatinine level isn't affected by the client's fluid status and remains within normal limits. A hematocrit of 52% and a BUN level of 8.6 mg/dl are elevated. Typically, the hematocrit and BUN level decrease.

Treatment of FVE involves dietary restriction of sodium. Which of the following food choices would be part of a low-sodium diet, mild restriction (2 to 3 g/day)?

Three ounces of light or dark meat chicken, 1 cup of spaghetti and a garden salad Ham (1,400 mg Na for 3 oz) and bacon (155 mg Na/slice) are high in sodium as is tomato juice (660 mg Na/¾ cup) and low fat cottage cheese (918 mg Na/cup). Packaged meals are high in sodium.

A client was admitted to the hospital unit after 2 days of vomiting and diarrhea. The client's spouse became alarmed when the client demonstrated confusion and elevated temperature, and reported "dry mouth." The nurse suspects the client is experiencing which condition?

dehydration Dehydration results when the volume of body fluid is significantly reduced in both extracellular and intracellular compartments. In dehydration, all fluid compartments have decreased volumes; in hypovolemia, only blood volume is low. The most common fluid imbalance in older adults is dehydration. Hypervolemia is caused by fluid intake that exceeds fluid loss, such as from excessive oral intake or rapid IV infusion of fluid. Early signs of hypervolemia are weight gain, elevated BP, and increased breathing effort. Hypercalcemia occurs when the serum calcium level is higher than normal. Some of its signs include tingling in the extremities and the area around the mouth (circumoral paresthesia) and muscle and abdominal cramps. Hyperkalemia is an excess of potassium in the blood. Symptoms include diarrhea, nausea, muscle weakness, paresthesias, and cardiac dysrhythmias.

When evaluating arterial blood gases (ABGs), which value is consistent with metabolic alkalosis?

pH 7.48 Metabolic alkalosis is a clinical disturbance characterized by a high pH and high plasma bicarbonate concentration. The HCO value is below normal. The PaCO value and the oxygen saturation level are within a normal range.

Which set of arterial blood gas (ABG) results requires further investigation?

pH 7.49, PaCO2 30 mm Hg, PaO2 89 mm Hg, and HCO3- 18 mEq/L