Ch 12: Fluid Volume and Electrolytes

ANS: D Rationale: Loop diuretics cause the body to lose potassium. Patients who take loop and thiazide diuretics should be monitored for hypokalemia.

A patient is taking a loop diuretic and reports anorexia and fatigue. The nurse suspects which electrolyte imbalance in this patient? a. Hypercalcemia b. Hypocalcemia c. Hyperkalemia d. Hypokalemia

ANS: D. Discontinue the infusion. Rationale: These are signs and symptoms of a blood transfusion reaction that could escalate to anaphylaxis; therefore, the blood transfusion should be stopped immediately.

A patient receiving a unit of red blood cells suddenly develops shortness of breath, chills, and fever. What will the nurse do first? a. Reassure the patient that this is an expected reaction. b. Notify the health care provider while a peer monitors the blood transfusion. c. Decrease the infusion rate and reassess the patient in 15 min. d. Discontinue the infusion.

ANS: B. Assess skin for flushing and assess increased thirst. Rationale: Flushed skin and increased thirst are signs and symptoms of hypernatremia.

The nurse is administering hypertonic saline solution to treat a patient with severe hyponatremia. Which is the priority nursing intervention? a. Monitor temperature. b. Assess skin for flushing and assess increased thirst. c. Administer antiemetic for vomiting. d. Monitor urinary output.

ANS: A Rationale: Vitamin D enhances the absorption of calcium in the body. Calcium and phosphorus have an inverse relationship—an increased level of one mineral decreases the level of the other, and they would bind in the gastrointestinal tract and not be absorbed if taken at the same time. Antacids can contain magnesium, which can promote calcium loss. Aspirin can alter vitamin D levels and interfere with calcium absorption.

A patient asks the nurse about taking calcium supplements to avoid hypocalcemia. The nurse will suggest that the patient follow which instruction? a. Take a calcium and vitamin D combination supplement. b. Take calcium along with phosphorus to improve absorption. c. Take calcium with antacids to reduce stomach upset. d. Use aspirin instead of acetaminophen when taking calcium.

ANS: B.

A patient gained 4.4 lb (2 kg), and it has been determined that the weight gain is caused by fluid retention. The nurse correctly estimates that the weight gain may be equivalent to approximately how much fluid? a. 1 L b. 2 L c. 6 L d. 8 L

ANS: B. Breath sounds Rationale: The patient presents with hypotension and generalized edema, indicating that fluid has shifted into the interstitial spaces and the patient lacks sufficient oncotic pressure to hold fluid in the vessels to maintain the blood pressure. Because a significant proportion of the patient's fluid is in the interstitial space, the goal of therapy is to pull fluid from the interstitial space into the intravascular space; the proper fluid with which to achieve this is a colloid, such as albumin. Therefore the nurse's priority is to monitor the patient's breath sounds because generalized edema can frequently involve pulmonary edema and because breathing is the second most basic need, between airway and circulation.

A patient has a blood pressure of 82/60 mm Hg with generalized edema. What should be the nurse's priority patient assessment in evaluating the effectiveness of fluid therapy? a. Serum albumin b. Breath sounds c. Patient weight d. Blood pressure

ANS: 100 Rationale: (200 mL x 15 gtt/mL) ÷ 30 min = 100 gtt/min.

A patient with cirrhosis is noted to have low serum albumin levels. The patient is to receive 200 mL of albumin in 30 minutes. The drop factor for the IV set is 15 gtt/mL. The nurse correctly adjusts the IV rate to what rate? _______________ gtt/min

ANS: C Rationale: Normal osmolality is 275 to 295 mOsm/kg. This patient is therefore hyper-osmolar.

A patient's serum osmolality is 305 mOsm/kg. Which term describes this patient's body fluid osmolality? a. Iso-osmolar b. Hypo-osmolar c. Hyper-osmolar d. Isotonic

ANS: C Rationale: Potassium chloride should be given intravenously when hypokalemia is severe, so this patient should receive IV potassium chloride. Potassium should never be given as a bolus and should be administered slowly. The maximum infusion rate for adults with a serum potassium level greater than 2.5 mEq/L is 10 mEq/h or 200 mEq/24 hours.

A patient has a serum potassium level of 2.7 mEq/L. The patient's provider has determined that the patient will need 200 mEq of potassium to replace serum losses. How will the nurse caring for this patient expect to administer the potassium? a. As a single-dose 200 mEq oral tablet b. As an intravenous bolus over 15 to 20 minutes c. In an intravenous solution at a maximum rate of 10 mEq/h d. In an intravenous solution at a rate of 45 mEq/h

ANS: A, B, D, E

A patient has hypernatremia. Which components are appropriate to include in the nursing teaching plan of care? (Select all that apply) a. Instruct patient on seizure precautions b. keep appointments for laboratory tests c. a sign of hypernatremia is muscle cramps d. explain the meaning of fluid restriction e. instruct patient on how to read food labels

ANS: B. 250 mL of red blood cells (RBCs) Rationale: The nurse should administer the RBCs to increase the patient's oxygen-carrying capacity because the patient has anemia. This therapy should also help alleviate tachycardia because the patient's tachycardia is most likely caused by the sympathetic nervous system (SNS) activation responding to hypoxemia. As the tissues receive more oxygenated blood from the infusion of additional hemoglobin found in the RBCs, the SNS stimulation should subside. In addition, improved tissue oxygenation should help improve healing.

A patient in the postoperative period has tachycardia, hemoglobin 9 g/100 mL, and a slowly healing wound. Which fluid therapy would the nurse expect to administer to help resolve these problems? a. 100 mL of fresh frozen plasma b. 250 mL of red blood cells (RBCs) c. 450 mL of whole blood d. 50 mL of 5% albumin

ANS: D Rationale: Lactated Ringer's solution is an isotonic solution and is used to replace water and electrolytes and is often used to replace gastrointestinal losses. Hypotonic fluids increase interstitial and intracellular hydration. Colloidal solutions are used to maintain plasma volume over time. Hypertonic solutions pull water from the interstitial space into the extracellular fluid.

A patient is admitted after experiencing vomiting and diarrhea for several days. The provider orders intravenous lactated Ringer's solution. The nurse understands that this fluid is given for which purpose? a. To increase interstitial and intracellular hydration b. To maintain plasma volume over time c. To pull water from the interstitial space into the extracellular fluid d. To replace water and electrolytes

ANS: A Rationale: This patient has signs of fluid volume excess. Urine specific gravity levels less than 1.010 g/mL indicate dilute urine and excess fluid. Diuretics are prescribed to reduce fluid overload.

A patient is admitted with orthopnea, cough, pulmonary crackles, and peripheral edema. The patient's urine specific gravity is 1.002. The nurse will expect this patient's provider to order which treatment? a. Diuretics b. Colloidal IV fluids c. Hypertonic IV fluids d. Hypotonic IV fluids

ANS: D Rationale: 6% Dextran 75 is a high-molecular-weight colloidal solution and is used to treat shock from hemorrhage, burns, or trauma. Colloids are plasma expanders, and the end result is an improvement in heart rate (decreased) and blood pressure (increased). Plasma expanders will result in an increase in urine output. Blood oxygenation is not affected, and colloids do not increase the amount of interstitial fluid.

A patient is being treated for shock after a motor vehicle accident. The provider orders 6% dextran 75 to be given intravenously. The nurse should expect which outcome as the result of this infusion? a. Decreased urine output b. Improved blood oxygenation c. Increased interstitial fluid d. Stabilization of heart rate and blood pressure

ANS: C.

A patient is receiving 10mEq of potassium chloride in 100mL of normal saline intravenously (IV) to infuse over 1 hour via infusion pump. The patient has a 22-guage peripheral IV in his right forearm and reports pain at the insertion site; the nurse notes that the site is reddened, warm, and tender to the touch. Which action would the nurse take? a. Aspirate and check for blood return, and then slow the IV rate b. Discontinue the IV, and then have a central line started c. Stop the infusion, and discontinue the IV immediately d. Apply warm compresses to the IV site and elevate extremity

ANS: A, B, C, E

A patient is receiving fluid replacement. The nurse's health teaching with this patient includes which suggestions? (Select all that apply) a. Measure the patient's weight every morning b. know that thirst means a fluid deficit c. monitor fluid intake and fluid output daily d. avoid using calcium & chloride supplements e. review patient's daily electrolyte labs for changes

ANS: B.

A patient is receiving intravenous (IV) potassium supplements. What is the most important nursing implications when administering this drug? a. It is administered via a central vascular access device b. It is diluted with IV fluids and delivered by infusion pump c. IV potassium must be chilled before administration d. IV potassium preparations should not contain preservatives

ANS: A, E, F Rationale: Patients who have hypocalcemia will exhibit laryngeal spasms, hyperactive deep tendon reflexes, and twitching of the mouth. The other symptoms are not characteristic of hypocalcemia.

A patient is suspected of having severe hypocalcemia. While waiting for the patient's serum electrolyte results, the nurse will assess for which symptoms? (Select all that apply.) a. Laryngeal spasms b. Fatigue c. Muscle weakness d. Nausea and vomiting e. Hyperactive deep tendon reflexes f. Twitching of the mouth

ANS: D Rationale: The patient's potassium level is within normal limits, but the urine output is decreased, so the patient should not be receiving IV potassium. The nurse should stop the IV and report the findings to the provider. The patient does not need an increase in potassium. The patient needs more fluids but not with potassium.

A patient who is being treated for dehydration is receiving 5% dextrose and 0.45% normal saline with 20 mEq/L potassium chloride at a rate of 125 mL/h. The nurse assuming care for the patient reviews the patient's serum electrolytes and notes a serum sodium level of 140 mEq/L and a serum potassium level of 3.6 mEq/L. The patient had a urine output of 250 mL during the last 12-hour shift. Which action will the nurse take? a. Contact the patient's provider to discuss increasing the potassium chloride to 40 mEq/L. b. Continue the intravenous fluids as ordered and reassess the patient frequently. c. Notify the provider and discuss increasing the rate of fluids to 200 mL/h. d. Stop the intravenous fluids and notify the provider of the assessment findings.

ANS: B. 5% dextrose and normal saline Rationale: Of the fluids listed, the only one that is hypertonic is 5% dextrose and normal saline. Normal saline is isotonic, and both 2.5% dextrose and water and 0.33% NaCl are considered to be hypotonic.

Based on the condition of the patient, an intravenous fluid that is hypertonic will be ordered. Which intravenous fluid is most likely to be ordered by the health care provider? a. 0.33% NaCl b. 5% dextrose and normal saline c. Normal saline d. 2.5% dextrose and water

ANS: C. 0.33% NaCl Rationale: Of the fluids listed, the only one that is hypotonic is 0.33% NaCl. Normal saline is isotonic; both D5NS and D5LR are considered to be hypertonic solutions.

Based on the condition of the patient, an intravenous fluid that is hypotonic will be ordered. Which intravenous fluid is most likely to be ordered by the health care provider? a. 5% dextrose and normal saline (D5NS) b. 5% dextrose and lactated Ringer (D5LR) c. 0.33% NaCl d. Normal saline

ANS: B. Stop the infusion. Rationale: The patient's safety is always the primary concern; the fluid should be stopped and the correct fluid hung before other measures are taken such as notifying the health care provider.

The health care provider has ordered 5% dextrose in water as a maintenance fluid for the patient. The nurse is assessing the patient at the beginning of the shift and observes the fluid hanging to be 50% dextrose in water (D50W). Which is the priority nursing action? a. Notify the health care provider of the error. b. Stop the infusion. c. Complete an incident report. d. Find out which nurse hung the D50W.

ANS: D.

The health care provider orders a hypertonic crystalloid IV solution for a 70-year-old patient. Which solution will the nurse hang? a. Lactated Ringer's b. 0.45% sodium chloride (NaCl) c. 0.9% sodium chloride (NaCl) d. 5% dextrose in 0.9% sodium chloride (NaCl)

ANS: B, E, F Rationale: The patient is hypoxemic and exhibits peripheral edema with hypertension; this is consistent with clinical indicators for hypervolemia. A diuretic that inhibits sodium reabsorption increases renal excretion of sodium and water; thus, as a result of therapy, the nurse expects the patient's weight to decrease from fluid loss. The nurse also expects the oxygen saturation to increase because oxygenation and ventilation become more efficient as fluid is drawn from the lungs and excreted in the urine. The nurse also expects the patient's urinary sodium to increase as a direct result of the administration of a diuretic that excretes sodium.

The nurse administers a diuretic that increases renal excretion of sodium to a patient with heart failure. The patient's assessment: blood pressure 154/88 mm Hg, oxygen saturation 92%, and peripheral edema. If therapy is successful, which effects on fluid and electrolyte balance does the nurse expect to see? (Select all that apply.) a. Low oncotic pressures b. Higher oxygen saturation c. Decreased urinary sodium d. More intravascular fluid e. Decreased body weight f. Decreased total body fluid

ANS: C. Serum albumin Rationale: The nurse checks the serum albumin level because unexplained dyspnea and edema are frequently related to hypoalbuminemia. As the serum albumin level falls in hypovolemia, the oncotic pressure (pulling power of protein in the vessels) of the intravascular fluid decreases until fluid starts to escape into the interstitial spaces of the lungs and periphery, leading to edema. This is the most likely cause of the edema because the patient developed a toxic reaction, which is caused by an excessive dose; however, the patient's dose was low. This means the blood did not have enough protein (albumin, primarily) to which the medication could bind.

The nurse administers a low dose of a medication to a male patient who has normal hepatic and renal function and no contraindications to therapy; however, afterward, the patient experiences a toxic reaction, dyspnea, and edema. The medication is highly protein-bound. Which parameter should the nurse assess to determine the most likely cause of these adverse effects? a. Blood pressure b. Urine output c. Serum albumin d. Fluid balance

ANS: B Rationale: A weight gain of 1 kg, or 2.2 to 2.5 lb, is equivalent to 1 L of fluid.

The nurse is administering intravenous fluids to a patient who is dehydrated. On the second day of care, the patient's weight is increased by 2.25 pounds. The nurse would expect that the patient's fluid intake has a. equaled urine output. b. exceeded urine output by 1 L. c. exceeded urine output by 2.5 L. d. exceeded urine output by 3 L.

ANS: A Rationale: If the patient is receiving potassium and the urine output is <25 mL/h or <600 mL/d, potassium accumulation may occur. Patients with a low urine output should not receive IV potassium. Arterial blood gases are not necessary prior to IV potassium administration. Potassium should never be given as a bolus. Patients should be put on a potassium-enriched diet when foods are tolerated.

The nurse is caring for a newly admitted patient who has severe gastroenteritis. The patient's electrolytes reveal a serum sodium level of 140 mEq/L and a serum potassium level of 3.5 mEq/L. The nurse receives an order for intravenous 5% dextrose and normal saline with 20 mEq/L potassium chloride to infuse at 125 mL/h. Which action is necessary prior to administering this fluid? a. Evaluate the patient's urine output. b. Contact the provider to order arterial blood gases. c. Request an order for an initial potassium bolus. d. Suggest a diet low in sodium and potassium.

ANS: D Rationale: Hypomagnesemia, like hypokalemia, enhances the action of digitalis and causes digitalis toxicity. Laxatives and diuretics can deplete both of these electrolytes.

The nurse is caring for a newly admitted patient who will receive digoxin to treat a cardiac dysrhythmia. The patient takes hydrochlorothiazide (HydroDIURIL) and reports regular use of over-the-counter laxatives. Before administering the first dose of digoxin, the nurse will review the patient's electrolytes with careful attention to the levels of which electrolytes? a. Calcium and magnesium b. Sodium and calcium c. Potassium and chloride d. Potassium and magnesium

ANS: A Rationale: Patients who are hyponatremic will have tachycardia and hypotension along with lethargy and muscle weakness. The normal range for serum sodium is 135 to 145 mEq/L; a serum sodium level of 126 mEq/L would be considered hyponatremic.

The nurse is caring for a patient who has a heart rate of 98 beats per minute and a blood pressure of 82/58 mm Hg. The patient is lethargic, is complaining of muscle weakness, and has had gastroenteritis for several days. Based on this patient's vital signs, which sodium value would the nurse expect? a. 126 mEq/L b. 140 mEq/L c. 145 mEq/L d. 158 mEq/L

ANS: C Rationale: Patients with hyponatremia may be treated with oral sodium supplements if the patient is able or if the deficit is mild. This patient is vomiting and would not be able to take supplements easily. For a serum sodium level between 125 and 135 mEq/L, normal saline may increase sodium content in vascular fluid. Hypertonic saline is used for severe hyponatremia with a serum sodium <120 mEq/L. Diuretics would further deplete sodium and fluid volume in a patient already likely to be dehydrated from severe vomiting.

The nurse is caring for a patient who has had severe vomiting. The patient's serum sodium level is 130 mEq/L. The nurse will expect the patient's provider to order which treatment? a. Diuretic therapy b. Intravenous hypertonic 5% saline c. Intravenous normal saline 0.9% d. Oral sodium supplements

ANS: A Rationale: The patient shows signs of fluid volume excess, so the nurse should slow the IV fluid rate and notify the provider. Increasing the rate would compound the problem. Colloidal and hypertonic fluids would pull more fluids into the intravascular space and compound the problem.

The nurse is caring for a patient who is receiving isotonic intravenous (IV) fluids at an infusion rate of 125 mL/h. The nurse performs an assessment and notes a heart rate of 102 beats per minute, a blood pressure of 160/85 mm Hg, and crackles auscultated in both lungs. Which action will the nurse take? a. Decrease the IV fluid rate and notify the provider. b. Increase the IV fluid rate and notify the provider. c. Request an order for a colloidal IV solution. d. Request an order for a hypertonic IV solution.

ANS: A Rationale: Oliguria, tachycardia, and abdominal cramping are signs of hyperkalemia, so the nurse should request an order for serum electrolytes. This patient should increase fluid intake. The patient is not exhibiting signs of hyperchloremia; the patient is showing signs of hyperkalemia, and an increased potassium dose is not indicated.

The nurse is caring for a patient who is receiving oral potassium chloride supplements. The nurse notes that the patient has a heart rate of 120 beats per minute and has had a urine output of 200 mL in the past 12 hours. The patient reports abdominal cramping. Which action will the nurse take? a. Contact the provider to request an order for serum electrolytes. b. Encourage the patient to consume less fluids. c. Report symptoms of hyperchloremia to the provider. d. Request an order to increase the patient's potassium dose.

ANS: C. Normal saline Rationale: Of the fluids listed, the only one that is isotonic is normal saline. Both D5NS and D5LR are considered to be hypertonic solutions; 0.33% NaCl is considered to be hypotonic.

The patient is ordered an isotonic intravenous fluid. Which intravenous fluid is most likely to be ordered by the health care provider? a. 5% dextrose and lactated Ringer (D5LR) b. 0.33% NaCl c. Normal saline d. 5% dextrose and normal saline (D5NS)

ANS: C. Apply oxygen. Rationale: The patient is high risk for cardiac dysrhythmias due to low potassium level. Oxygen and IV fluids are not a priority; Kayexalate is am exchange resin used to treat hyperkalemia.

Which is the priority intervention when the nurse is assessing a patient with a potassium level of 3.2 mEq/L? a. Start IV fluids. b. Administer Kayexalate. c. Apply oxygen. d. Attach telemetry leads for monitoring.

ANS: A Rationale: The recommended daily fluid intake for adults is 30 to 40 mL/kg/day. This patient should have a minimum of 2250 mL/day and is currently receiving 1200 mL IV plus 100 mL orally for a total of 1300 mL. Increasing the IV rate to 90 mL/h would give the patient 2160 mL. If the patient continues to take oral fluids, the amount of 2250 mL can be met. A rate of 150 mL/h would give the patient 3600 mL/day, which exceeds the recommended amount. Since this patient is not taking fluids well and is not receiving adequate IV fluids, encouraging an increased fluid intake is not indicated. Even if the patient drank 250 mL of water every 8 hours, the amount would not be sufficient.

The nurse is caring for a patient who weighs 75 kg. The patient has intravenous (IV) fluids infusing at a rate of 50 mL/h and has consumed 100 mL of fluids orally in the past 24 hours. Which action will the nurse take? a. Contact the provider to ask about increasing the IV rate to 90 mL/h. b. Discuss with the provider the need to increase the IV rate to 150 mL/h. c. Encourage the patient to drink more water so the IV can be discontinued. d. Instruct the patient to drink 250 mL of water every 8 hours.

ANS: A Rationale: Calcium gluconate is given to treat hyperkalemia in order to decrease irritability of the myocardium. When administered to a patient taking digitalis, it can cause digitalis toxicity. The other drugs may affect potassium levels but are not a cause for concern with calcium gluconate.

The nurse is caring for a patient who will receive 10% calcium gluconate to treat a serum potassium level of 5.9 mEq/L. The nurse performs a drug history prior to beginning the infusion. Which drug taken by the patient would cause concern? a. Digitalis b. Hydrochlorothiazide c. Hydrocortisone d. Vitamin D

ANS: B, E, F Rationale: Calcium gluconate has the same action on the heart as digitalis and combined use can place the patient at risk for digitalis toxicity. Hypercalcemia can cause ECG changes. A serum calcium level greater than 2.5 mEq/L indicates hypercalcemia and therefore should be reported. Calcium does not require infusion through a central line and should not be given as a rapid IV bolus. Calcium should not be added to a solution containing bicarbonate, because rapid precipitation occurs.

The nurse is caring for a patient who will receive intravenous calcium gluconate. Which nursing actions are appropriate when giving this solution? (Select all that apply.) a. Administering through a central line b. Review the patients medication record to see if they are receiving digitalis c. Giving as a rapid intravenous bolus d. Mixing in a solution containing sodium bicarbonate e. Monitoring the patient's electrocardiogram (ECG) f. Reporting a serum calcium level of >2.5 mEq/L

ANS: A Rationale: Mild hyperkalemia may be treated with dietary restriction of potassium-rich foods. The patient's sodium level is normal, so sodium bicarbonate is not indicated. Kayexalate is used for severe hyperkalemia. Salt substitutes contain potassium and would only compound the hyperkalemia.

The nurse is caring for a patient whose serum sodium level is 140 mEq/L and serum potassium level is 5.4 mEq/L. The nurse will contact the patient's provider to discuss an order for: a. a low-potassium diet. b. intravenous sodium bicarbonate. c. Sodium polystyrene sulfonate (Kayexalate). d. salt substitutes.

ANS: A Rationale: Patients with FVD will exhibit elevated temperature, tachycardia, tachypnea, hypotension, orthostatic hypotension, and cool, clammy skin. Patients with FVE will have bounding pulses, elevated blood pressure, dyspnea, and crackles. Mild ECF deficit causes thirst. Renal failure generally leads to FVE.

The nurse is performing an assessment on a patient brought to the emergency department for treatment for dehydration. The nurse assesses a respiratory rate of 26 breaths/minute, a heart rate of 110 beats/minute, a blood pressure of 86/50 mm Hg, and a temperature of 39.5° C. The patient becomes dizzy when transferred from the wheelchair to a bed. The nurse notes cool, clammy skin. Which diagnosis does the nurse suspect? a. Fluid volume deficit (FVD) b. Fluid volume excess (FVE) c. Mild extracellular fluid (ECF) deficit d. Renal failure

ANS: D. Normal saline Rationale: Of the intravenous solutions listed, the only one that is compatible with blood products is normal saline.

The nurse is preparing to administer a transfusion of a blood product. What is the most appropriate intravenous fluid to hang as a maintenance infusion? a. Lactated Ringer b. 5% dextrose and water c. Ringer solution d. Normal saline

ANS: B Rationale: Hypokalemia increases the risk for digoxin toxicity, so the nurse should hold the dose and notify the provider. Potassium should never be given as an IV bolus. Oral supplements are not used when hypokalemia is severe.

The nurse is preparing to administer digoxin to a patient who is newly admitted to the intensive care unit. The nurse reviews the patient's admission electrolytes and notes a serum potassium level of 2.9 mEq/L. Which action by the nurse is correct? a. Administer the digoxin and monitor the patient's electrocardiogram closely. b. Hold the digoxin dose and notify the provider of the patient's lab values. c. Request an order for an intravenous bolus of potassium. d. Request an order for oral potassium supplements.

ANS: A, B, E

The nurse is reviewing the medication list of a patient with hypokalemia. Which products may contribute to the cause of this imbalance? (Select all that apply) a. cortisone b. licorice c. azithromycin d. estrogen e. digoxin

ANS: D. Confirm the identity of the patient. Rationale: Although all of the actions listed are important, the highest priority is confirmation of the identity of the patient. Failure to do this is a major safety violation.

The patient has been ordered to receive a unit of packed red blood cells. What is the priority nursing action prior to initiating the infusion of the blood product? a. Verify that a large bore IV is in place. b. Verify that the permit for infusion was witnessed. c. Collect the blood product from the blood bank. d. Confirm the identity of the patient.

ANS: C Rationale: Severe hyperkalemia, with a potassium level of 6.9 mEq/L, requires aggressive treatment to increase the body's excretion of potassium. Kayexalate is a potassium binder used to treat severe hyperkalemia. The normal range for serum potassium is 3.5 to 5.5 mEq/L, so patients with the other potassium levels would not be treated aggressively or would need potassium supplementation.

The provider has ordered sodium polystyrene sulfonate (Kayexalate) to be administered to a patient. The nurse caring for this patient would expect which serum electrolyte values prior to administration of this therapy? a. Sodium 125 mEq/L and potassium 2.5 mEq/L b. Sodium 150 mEq/L and potassium 3.6 mEq/L c. Sodium 135 mEq/L and potassium 6.9 mEq/L d. Sodium 148 mEq/L and potassium 5.5 mEq/L

ANS: A. Hypokalemia

Three days after a patient's total colectomy and ileostomy, he has a nasogastric tube for continuous suction and a Foley catheter for continuous drainage. The night nurse reports a high output from the ileostomy. The patient's pulse is irregular, and he reports leg weakness. Based on this situation, the nurse would correctly suspect what kind of imbalance. a. Hypokalemia b. Hyperkalemia c. Hyponatremia d. Hypercalcemia

ANS: A. Administer the medication using an infusion device. Rationale: Too rapid infusion of potassium can cause cardiac dysrhythmias; an intravenous infusion device must always be used. Potassium should not be bolused or pushed. Heat will not aid the infusion. Unless the patient is prone to constant hypokalemia, teaching the signs and symptoms is not a priority.

What is the priority nursing intervention when administering intravenous potassium replacement to the patient? a. Administer the medication using an infusion device. b. Teach the patient and family the signs and symptoms of hypokalemia. c. Administer potassium as a bolus over 10 min. d. Apply heat to the site of intravenous administration.

ANS: A, B, C, F Rationale: The patients who should receive magnesium supplements include the patient with heart failure, because magnesium is essential to cardiovascular function, and patients with liver failure, because of malabsorption. Because potassium and magnesium imbalances frequently occur together, a patient with hypokalemia can be a suitable candidate for magnesium repletion because the serum magnesium is restored before repleting the potassium. Vegetarians can find magnesium in milk, cheese, yogurt, and bran.

Which conditions or circumstances would indicate that the patients are potentially suitable candidates for magnesium sulfate supplements by mouth? (Select all that apply.) a. Heart failure b. Hypokalemia c. Vegetarian diet d. Renal failure e. Preeclampsia f. Liver failure

ANS: Calcium Rationale: Calcium, in addition to helping strengthen bones, is important in the transmission of nerve impulses and is vital for muscle contractions, among many other physiologic functions.

Which dietary supplement is critical to the proper function of nerve impulse transmission and muscle contractions? a. Pyridoxine b. Calcium c. Cobalamin d. Chromium

ANS: B. Phosphorus Rationale: Bone strength depends on the size and density of bone, and bone density depends on the bone concentrations of calcium, phosphorus, and other minerals.

Which dietary supplement is needed in combination with calcium to promote the development of strong bones and teeth? a. Zinc b. Phosphorus c. Vitamin C d. Cobalamin

ANS: A. Sodium Rationale: The major cation of extracellular fluid is sodium.

Which electrolyte is the major cation of extracellular fluid? a. Sodium b. Chloride c. Potassium d. Phosphorous

ANS: B. Potassium Rationale: The major cation of intracellular fluid is potassium.

Which electrolyte is the major ion of the intracellular space? a. Sodium b. Potassium c. Chloride d. Phosphorous

ANS: A. A 6 kilogram (13.2 lb) 2-month-old neonate is 75% to 80% water. Rationale: The TBW of a 70 kg (154 lb) man is approximately 60% (40 L). This percentage varies with age, sex, and percentage of body fat. Neonates are 75% to 80% water, whereas older adults are 45% to 55% water. Women tend to have less body water than men due to the effects of hormones and higher amount of adipose tissue, which contains very little water.

Which statement accurately describes the total body water (TBW) composition compared to weight? a. A 6 kilogram (13.2 lb) 2-month-old neonate is 75% to 80% water. b. A 60 kilogram 70-year-old is 75% water. c. A 3 kg 2-week-old is 95% water. d. A 70 kilogram (154 lb) 40-year-old man is 40% water.