Chapter 13 prep U Electrolytes

Which factor increases blood urea nitrogen (BUN)? A. Decreased protein intake B. Gastrointestinal bleeding C. Hypothermia D. Overhydration

Ans: B Feedback: Factors that increase BUN include gastrointestinal bleeding, decreased renal function, dehydration, increased protein intake, fever, and sepsis.

A client has a respiratory rate of 38 breaths/min. What effect does breathing faster have on arterial pH level? A. Decreases arterial pH B. Increases arterial pH C. Provides long-term pH regulation D. No effect

Ans: B Feedback: Respiratory alkalosis is always caused by hyperventilation, which is a decrease in plasma carbonic acid concentration. The pH is elevated above normal as a result of a low PaCO2.

A volume-depleted patient would present with which of the following diagnostic lab results? A. BUN-to-creatinine ratio of 24:1 B. Urine specific gravity of 1.02 C. Capillary refill time of 3 seconds D. Urinary output of 1.2 L/24 hours

Ans: A Feedback: A BUN-to-serum creatinine concentration ratio greater than 20:1 is indicative of volume depletion. The other results are within normal range.

A client is diagnosed with syndrome of inappropriate antidiuretic hormone (SIADH). Laboratory results reveal serum sodium level 130 mEq/L and urine specific gravity 1.030. Which nursing intervention helps prevent complications associated with SIADH? A. Restricting fluids to 800 ml/day B. Administering vasopressin as ordered C. Restricting sodium intake to 1 gm/day D. Elevating the head of the client's bed to 90 degrees

Ans: A Feedback: Excessive release of antidiuretic hormone (ADH) disturbs fluid and electrolyte balance in SIADH. The excessive ADH causes an inability to excrete dilute urine, retention of free water, expansion of extracellular fluid volume, and hyponatremia. Symptomatic treatment begins with restricting fluids to 800 ml/day. Vasopressin is administered to clients with diabetes insipidus a condition in which circulating ADH is deficient. Elevating the head of the bed decreases vascular return and decreases atrial-filling pressure, which increases ADH secretion, thus worsening the client's condition. The client's sodium is low and, therefore, shouldn't be restricted.

With which condition should the nurse expect that a decrease in serum osmolality will occur? A. Kidney failure B. Diabetes insipidus C. Uremia D. Hyperglycemia

Ans: A Feedback: Failure of the kidneys results in multiple fluid and electrolyte abnormalities including fluid volume overload. If renal function is so severely impaired that pharmacologic agents cannot act efficiently, other modalities are considered to remove sodium and fluid from the body.

Which sign suggests that a client with the syndrome of inappropriate antidiuretic hormone (SIADH) secretion is experiencing complications? A. Jugular vein distention B. Weight loss C. Polyuria D. Tetanic contractions

Ans: A Feedback: SIADH secretion causes antidiuretic hormone overproduction, which leads to fluid retention. Severe SIADH can cause such complications as vascular fluid overload, signaled by jugular vein distention. This syndrome isn't associated with tetanic contractions. It may cause weight gain and fluid retention (secondary to oliguria).

You are caring for a new client on your unit who is third-spacing fluid. You know to assess for what type of edema? A. Generalized B. Dependent C. Brassy D. Pitting

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

What clinical indication of hyperphosphatemia does the nurse assess in a patient? A. Bone pain B. Tetany C. Seizures D. Paresthesia

Ans: B Feedback: Tetany is a symptom of hyperphosphatemia. Bone pain, paresthesia, and seizures are associated with hypophosphatemia.

Clients diagnosed with hypervolemia should avoid sweet or dry food because it A. can lead to weight gain. B. increases the client's desire to consume fluid. C. can cause dehydration. D. obstructs water elimination.

Ans: B Feedback: The management goal in hypervolemia is to reduce fluid volume. For this reason, fluid is rationed and the client is advised to take a limited amount of fluid when thirsty. Sweet or dry food can increase the client's desire to consume fluid. Sweet or dry food does not obstruct water elimination or cause dehydration. Weight regulation is not part of hypervolemia management except to the extent it is achieved on account of fluid reduction.

Which laboratory result does the nurse identify as a direct result of the client's hypovolemic status with hemoconcentration? A. Low urine specific gravity B. Elevated hematocrit level C. Low white blood count D. Abnormal potassium level

Ans: B Feedback: When hemoconcentration occurs due to a hypovolemic state, a high ratio of blood components in relation to watery plasma occurs, thus causing an elevated hematocrit level. A high white blood cell count and urine specific gravity is also noted. Other causes of an abnormal potassium level may be present.

Which medication does the nurse anticipate administering to antagonize the effects of potassium on the heart for a patient in severe metabolic acidosis? A. Magnesium sulfate B. Furosemide C. Sodium bicarbonate D. Calcium gluconate

Ans: C Feedback: IV administration of sodium bicarbonate may be necessary in severe metabolic acidosis to alkalinize the plasma, shift potassium into the cells, and furnish sodium to antagonize the cardiac effects of potassium.

Which condition leads to chronic respiratory acidosis in older adults? A. Overuse of sodium bicarbonate B. Erratic meal patterns C. Thoracic skeletal change D. Decreased renal function

Ans: C Feedback: Poor respiratory exchange as the result of chronic lung disease, inactivity, or thoracic skeletal changes may lead to chronic respiratory acidosis. Decreased renal function in older adults can cause an inability to concentrate urine and is usually associated with fluid and electrolyte imbalance. A poor appetite, erratic meal patterns, inability to prepare nutritious meals, or financial circumstances may influence nutritional status, resulting in imbalances of electrolytes. Overuse of sodium bicarbonate may lead to metabolic alkalosis.

A nurse caring for a patient with metabolic alkalosis knows to assess for the primary, compensatory mechanism of: A. Decreased PaCO2. B. Decreased serum HCO3. C. Increased PaCO2. D. Increased serum HCO3.

Ans: C Feedback: The respiratory system compensates by decreasing ventilation to conserve CO2 and increase the PaCO2.

The nursing student asks their instructor what the term is for the amount of hydrogen ions in a solution. What should the instructor respond? A. H+ B. ATP C. pH D. DTATP

Ans: C Feedback: The symbol pH refers to the amount of hydrogen ions in a solution; pH can range from 1, which is highly acidic, to 14, which is highly basic. All other options are incorrect.

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. A. Tender area around the insertion site B. Cool area around the insertion site C. Reddened area along the path of the vein D. Ecchymosis at the insertion site E. Rapid, shallow respirations

Ans: C,D Feedback: Phlebitis is inflammation of a vein and is characterized by a reddened, warm area around an insertion site or along the path of a vein. The involved area is also tender and swollen. The nurse assesses infusion sites and determines the proper action to take. If indications lead to suspected phlebitis, the nurse will discontinue the intravenous line and restart with a different vessel.

A nurse reviews the results of an electrocardiogram (ECG) for a patient who is being assessed for hypokalemia. Which of the following would the nurse notice as the most significant diagnostic indicator? A. Widened QRS wave B. Flat P wave C. Peaked T wave D. Elevated U wave

Ans: D Feedback: An elevated U wave is specific for hypokalemia. Flat or inverted T waves may also be present. The other tracings are consistent with hyperkalemia.

Which of the following is the most common cause of symptomatic hypomagnesemia in the United States? A. Alcoholism B. Intestinal resection C. Loss of gastric acid D. Inflammatory bowel disease

Ans: A Feedback: Alcoholism is currently the most common cause of symptomatic hypomagnesemia in the United States. Any disruption in small bowel function, as in intestinal resection or inflammatory bowel disease, can lead to hypomagnesemia.

A patient has been involved in a traumatic accident and is hemorrhaging from multiple sites. The nurse expects that the compensatory mechanisms associated with hypovolemia would cause what clinical manifestations? (Select all that apply.) A. Tachypnea B. Tachycardia C. Bradycardia D. Hypertension E. Oliguria

Ans: A, B, E Feedback: Hypovolemia, or fluid volume deficit, is indicated by decreased, not increased, blood pressure (hypotension), oliguria, tachycardia (not bradycardia), and tachypnea.

A client has chronic hyponatremia, which requires weekly laboratory monitoring to prevent the client lapsing into convulsions or a coma. What is the level of serum sodium at which a client can experience these side effects? A. 135 mEq/L B. 114 mEq/L C. 130 mEq/L D. 148 mEq/L

Ans: B Feedback: Hyponatremia occurs when the serum sodium level dips below 135 mEq/L. When serum sodium levels fall below 115mEq/L, mental confusion, muscular weakness, anorexia, restlessness, elevated body temperature, tachycardia, nausea, vomiting, personality changes, convulsions, or coma can occur. A serum sodium level of 148 mEq/L would indicate hypernatremia. Normal serum concentration levels range from 135 to 145 mEq/L.

Which arterial blood gas (ABG) result would the nurse anticipate for a client with a 3-day history of vomiting? A. pH: 7.28, PaCO2: 25 mm Hg, HCO3: 15 B. pH: 7.55, PaCO2: 60 mm Hg, HCO3-: 28 C. pH: 7.34, PaCO2: 60 mm Hg, HCO3: 34 D. pH: 7.45, PaCO2: 32 mm Hg, HCO3-: 21

Ans: B Feedback: The client's ABG would likely demonstrate metabolic alkalosis. Metabolic alkalosis is a clinical disturbance characterized by a high pH (decreased H+ concentration) and a high plasma bicarbonate concentration. It can be produced by a gain of bicarbonate or a loss of H+. A common cause of metabolic alkalosis is vomiting or gastric suction with loss of hydrogen and chloride ions. The disorder also occurs in pyloric stenosis, where only gastric fluid is lost. The other results do not represent metabolic alkalosis.

The nurse is caring for a client undergoing alcohol withdrawal. Which serum laboratory value should the nurse monitor most closely? A. Magnesium B. Phosphorus C. Calcium D. Potassium

Ans: A Feedback: Chronic alcohol abuse is a major cause of symptomatic hypomagnesemia in the United States. The serum magnesium concentration should be measured at least every 2 or 3 days in clients undergoing alcohol withdrawal. The serum magnesium concentration may be normal at admission but may decrease as a result of metabolic changes, such as the intracellular shift of magnesium associated with intravenous glucose administration.

A patient has a serum osmolality of 250 mOsm/kg. The nurse knows to assess further for: A. Hyponatremia. B. Dehydration. C. Hyperglycemia. D. Acidosis.

Ans: A Feedback: Decreased serum sodium is a factor associated with decreased serum osmolality. Dehydration and hyperglycemia are associated with increased serum osmolality; acidosis is associated with increased urine osmolality.

The nurse should assess the patient for signs of lethargy, increasing intracranial pressure, and seizures when the serum sodium reaches what level? A. 115 mEq/L B. 160 mEq/L C. 130 mEq/L D. 145 mEq/L

Ans: A Feedback: Features of hyponatremia associated with sodium loss and water gain include anorexia, muscle cramps, and a feeling of exhaustion. The severity of symptoms increases with the degree of hyponatremia and the speed with which it develops. When the serum sodium level decreases to less than 115 mEq/L (115 mmol/L), signs of increasing intracranial pressure, such as lethargy, confusion, muscle twitching, focal weakness, hemiparesis, papilledema, seizures, and death, may occur.

The nurse is conducting a lecture on the difference between hypovolemia and dehydration. When completing a verbal comparison, which point needs clarified? A. In dehydration, only extracellular is depleted. B. Similar causes are present in both conditions. C. Hypovolemia contains only low blood volume. D. Both conditions result in abnormal laboratory studies.

Ans: A Feedback: In clients diagnosed with dehydration, all fluid compartments including the intracellular and extracellular compartment are reduced. The other options are correct. Both states can be from similar disease process such as vomiting, fever, diarrhea and difficulty swallowing and also have abnormal lab work. It is correct that hypovolemia relates to low blood volume.

A nurse is assessing a client with syndrome of inappropriate antidiuretic hormone. Which finding requires further action? A. Weight loss B. Jugular vein distention C. Polyuria D. Tetanic contractions

Ans: B Feedback: Jugular vein distention requires further action because this finding signals vascular fluid overload. Tetanic contractions aren't associated with this disorder, but weight gain and fluid retention from oliguria are. Polyuria is associated with diabetes insipidus, which occurs with inadequate production of antidiuretic hormone.

The nurse is participating in the care of a client who had a peripherally inserted central catheter (PICC) placed in the right arm. After catheter placement, the nurse should complete which action? A. Administer the prescribed IV fluids. B. Send the client for a chest x-ray. C. Assess the client's blood pressure (BP) on the right arm. D. Obtain written consent for the procedure.

Ans: B Feedback: A chest x-ray is needed to confirm the placement of catheter tip before initiating ordered infusions. Consent should be obtained before, not after, the procedure. No BPs should be taken on the extremity where the catheter is placed.

A client is diagnosed with syndrome of inappropriate antidiuretic hormone (SIADH). The nurse should anticipate which laboratory test result? A. Hematocrit of 52% B. Serum sodium level of 124 mEq/L C. Serum blood urea nitrogen (BUN) level of 8.6 mg/dl D. Serum creatinine level of 0.4 mg/dl

Ans: B Feedback: 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.

What does the nurse recognize as one of the best indicators of the patient's renal function? A. Urine osmolality B. Blood urea nitrogen C. Serum creatinine D. Specific gravity

Ans: C Feedback: Creatinine is the end product of muscle metabolism. It is a better indicator of renal function than BUN because it does not vary with protein intake and metabolic state.

The nurse is caring for a client with laboratory values indicating dehydration. Which clinical symptom is consistent with the dehydration? A. Crackles in the lung fields B. Cool and pale skin C. Dark, concentrated urine D. Distended jugular veins

Ans: C Feedback: Dehydration indicates a fluid volume deficit. Dark, concentrated urine indicates a lack of fluid volume. Adding more fluid would dilute the urine. The other options indicate fluid excess.

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? A. Sodium level of 137 mEq/L B. Potassium level of 6 mEq/L C. Sodium level of 150 mEq/L D. Potassium level of 3.8 mEq/L

Ans: C Feedback: Hypernatremia (normal serum sodium is 135 to 145 mEq/L) is consistent with increased fluid loss and dehydration in diabetes insipidus.

A fluid volume deficit can be caused by either dehydration or hypovolemia. What is the distinction between the two? A. In hypovolemia all fluid compartments have decreased volumes. B. In dehydration intracellular fluid volume is depleted. C. In hypovolemia only blood volume is low. D. In dehydration only blood volume is low.

Ans: C Feedback: 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. This makes options A, B, and D incorrect.

Which is the most common cause of symptomatic hypomagnesemia? A. Alcoholism B. Intravenous drug use C. Burns D. Sedentary lifestyle

Ans: A Feedback: Alcoholism is currently the most common cause of symptomatic hypomagnesemia. Intravenous drug use, sedentary lifestyle, and burns are not the most common causes of hypomagnesemia.

A patient with a history of poorly controlled type 1 diabetes has begun displaying the characteristic signs and symptoms of diabetic nephropathy. The patient's nurse recognizes that the patient is at risk of disruptions to fluid balance. What role do the kidneys play in the maintenance of normal fluid balance? A. Selectively retaining needed substances and excreting waste products B. Synthesizing and releasing angiotensin in cases of fluid volume deficit C. Maintaining the correct concentration of H+ ions in the blood D. Secreting or withholding antidiuretic hormone in response to extracellular fluid volume

Ans: A FeedbacK: Major functions of the kidneys in maintaining normal fluid balance include regulation of extracellular fluid (ECF) volume and osmolality by selective retention and excretion of body fluids and regulation of electrolyte levels in the ECF by selective retention of needed substances and excretion of unneeded substances. Antidiuretic hormone (ADH) is secreted by the pituitary gland, and angiotensin is ultimately derived from the liver, not the kidneys. Concentration of H+ ions contributes the buffer action of the kidneys, not the maintenance of fluid balance.

The nurse is caring for a client being treated with isotonic IV fluid for hypernatremia. What complication of hypernatremia should the nurse continuously monitor for? A. Renal failure B. Red blood cell hydrolysis C. Red blood cell crenation D. Cerebral edema

Ans: D Feedback: Treatment of hypernatremia consists of a gradual lowering of the serum sodium level by the infusion of a hypotonic electrolyte solution (e.g., 0.3% sodium chloride) or an isotonic nonsaline solution (e.g., dextrose 5% in water [D5W]). D5W is indicated when water needs to be replaced without sodium. Clinicians consider a hypotonic sodium solution to be safer than D5W because it allows a gradual reduction in the serum sodium level, thereby decreasing the risk of cerebral edema. It is the solution of choice in severe hyperglycemia with hypernatremia. A rapid reduction in the serum sodium level temporarily decreases the plasma osmolality below that of the fluid in the brain tissue, causing dangerous cerebral edema.

A client's potassium level is elevated. The nurse is reviewing the ECG tracing. Identify the area on the tracing where the nurse would expect to see peaks?

Ans: T wave peaks Feedback: Potassium influences cardiac muscle activity. Alterations in potassium levels change myocardial irritability and rhythm. Hyperkalemia is very dangerous; cardiac arrest can occur. Cardiac effects of elevated serum potassium are significant when the level is above 8 mEq/L. Hyperkalemia causes skeletal muscle weakness and even paralysis, related to a depolarization block in t muscle. Therefore, ventricular conduction is slowed. The earliest change that can be seen are peaked, narrow T waves on the ECG.

The weight of a client with congestive heart failure is monitored daily and entered into the medical record. In a 24-hour period, the client's weight increased by 2 lb. How much fluid is this client retaining? A. 1500 ml B. 500 ml C. 1250 ml D. 1 L

Ans:D Feedback: A 2-lb weight gain in 24 hours indicates that the client is retaining 1L of fluid.

Which condition might occur with respiratory acidosis? A. Increased intracranial pressure B. Decreased blood pressure C. Mental alertness D. Decreased pulse

Ans: A Feedback: If respiratory acidosis is severe, intracranial pressure may increase, resulting in papilledema and dilated conjunctival blood vessels. Increased blood pressure, increased pulse, and decreased mental alertness occur with respiratory acidosis.

A client with chronic renal failure has a serum potassium level of 6.8 mEq/L. What should the nurse assess first? A. Pulse B. Blood pressure C. Respirations D. Temperature

Ans: A Feedback: An elevated serum potassium level may lead to a life-threatening cardiac arrhythmia, which the nurse can detect immediately by palpating the pulse. In addition to assessing the client's pulse, the nurse should place the client on a cardiac monitor because an arrythmia can occur suddenly. The client's blood pressure may change, but only as a result of the arrhythmia. Therefore, the nurse should assess blood pressure later. The nurse also may delay assessing respirations and temperature because these aren't affected by the serum potassium level.

A nurse is providing an afternoon shift report and relates morning assessment findings to the oncoming nurse. Which daily assessment data is necessary to determine changes in the client's hypervolemia status? A. weight B. vital signs C. edema D. intake and output

Ans: A Feedback: Daily weight provides the ability to monitor fluid status. A 2-lb (0.9 kg) weight gain in 24 hours indicates that the client is retaining 1 L of fluid. Also, the loss of weight can indicate a decrease in edema. Vital signs do not always reflect fluid status. Edema could represent a shift of fluid within body spaces and not a change in weight. Intake and output do not account for unexplainable fluid loss.

A client reports muscle cramps in the calves and feeling "tired a lot." The client is taking ethacrynic acid (Edecrin) for hypertension. Based on these symptoms, the client will be evaluated for which electrolyte imbalance? A. hypokalemia B. hypercalcemia C. hypocalcemia D. hyperkalemia

Ans: A Feedback: Hypokalemia causes fatigue, weakness, anorexia, nausea, vomiting, cardiac dysrhythmias, leg cramps, muscle weakness, and paresthesias. Many diuretics, such as ethacrynic acid (Edecrin), also waste potassium. Symptoms of hyperkalemia include diarrhea, nausea, muscle weakness, paresthesias, and cardiac dysrhythmias. Signs of hypocalcemia include tingling in the extremities and the area around the mouth and muscle and abdominal cramps. Hypercalcemia causes deep bone pain, constipation, anorexia, nausea, vomiting, polyuria, thirst, pathologic fractures, and mental changes.

A client presents with severe diarrhea and a history of chronic renal failure to the emergency department. Arterial blood gas results are as follows: pH 7.30 PaO2 97 PaCO2 37 HCO3 18 The nurse would expect which of the following sets of assessment findings? A. Clammy skin, blood pressure 86/46, headache B. Confusion, respiratory rate 8 breaths/min, dry skin C. Blood pressure 188/120, nausea, vomiting D. Headache, blood pressure 90/54, dry skin

Ans: A Feedback: Metabolic acidosis, a common clinical disturbance, is characterized by decreased pH and plasma bicarbonate concentration. Common causes of metabolic acidosis include diarrhea, chronic renal failure, use of diuretics, intestinal fistulas, and ureterostomies. The client will experience the following signs and symptoms: headache, confusion, increased respiratory rate, nausea, vomiting, cold and clammy skin, and decreased blood pressure.

A nurse is caring for a client with acute renal failure and hypernatremia. In this case, which action can be delegated to the nursing assistant? A. Provide oral care every 2-3 hours. B. Monitor for signs and symptoms of dehydration. C. Teach the client about increased fluid intake. D. Assess the client's weight daily for trends.

Ans: A Feedback: Providing oral care for the client every 2-3 hours is within the scope of practice of a nursing assistant. The other actions should be completed by the registered nurse.

The Emergency Department (ED) nurse is caring for a client who is known to make excessive use of laxatives who is showing signs of bradycardia. The client is admitted for hemodialysis. The ED nurse knows that a major goal of managing this client is what? A. Flush out excess magnesium B. Provide mechanical ventilation C. Stop all laxatives D. Prevent magnesium sulfate reactions

Ans: A Feedback: The main objective is to flush out excess magnesium. Laxatives contain magnesium, and their excessive use may cause hypermagnesemia. Bradycardia or slow heart rate is one of the signs of this imbalance. In severe cases, hemodialysis may be necessary. Magnesium sulfate is administered in hypomagnesemia and not hypermagnesemia. Mechanical ventilation is necessary only if there is a change in respiratory rate, rhythm, or depth. The physician may permit the use of magnesium-free laxatives and the client should follow the recommended frequency of their use.

A client with a magnesium concentration of 2.6 mEq/L (1.3 mmol/L) is being treated on a medical-surgical unit. Which treatment should the nurse anticipate will be used? A. Intravenous furosemide B. Fluid restriction C. Dialysis D. Oral magnesium oxide

Ans: A Feedback: The nurse should anticipate the administration of furosemide for the treatment of hypermagnesemia. Administration of loop diuretics (e.g., furosemide) and sodium chloride or lactated Ringer intravenous solution enhances magnesium excretion in clients with adequate renal function. Fluid restriction is contraindicated. The client should be encouraged to increase fluids to promote the excretion magnesium through the urine. Magnesium oxide is contraindicated because it would further elevate the client's serum magnesium concentration. In acute emergencies, when the magnesium concentration is severely elevated, hemodialysis with a magnesium-free dialysate can reduce the serum magnesium to a safe concentration within hours.

Upon shift report, the nurse states the following laboratory values: pH, 7.44; PCO2, 30mmHg; and HCO3,21 mEq/L for a client with noted acid-base disturbances. Which acid-base imbalance do both nurses agree is the client's current state? A. Compensated respiratory alkalosis B. Compensated metabolic alkalosis C. Uncompensated respiratory alkalosis D. Compensated metabolic acidosis

Ans: A Feedback: The question states that the client has a history of acid-base disturbance. The nurse would first note that the pH has returned to close to normal indicating compensation. The nurse then assess the PCO2 (normal: 35 to 45 mm Hg) and HCO3 (normal: 22 to 27mEq/L) levels. In a respiratory condition, the pH and the PCO2 move in opposite direction; thus, the pH rises and the PCO2 drops (alkalosis) or vice versa (acidosis). In a metabolic condition, the pH and the bicarbonate move in the same direction; if the pH is low, the bicarbonate level will be low, also. In this client, the pH is at the high end of normal, indicating compensation and alkalosis. The PCO2 is low, indicating a respiratory condition (opposite direction of the pH).

It is important for a nurse to know how to calculate the corrected serum calcium level for a patient when hypocalcemia is seen along with low serum albumin levels. Calculate the corrected serum calcium when the serum calcium is 9 mg/dL and the serum albumin is 3 g/dL. A. 9.8 mg/dL B. 11 mg/dL C. 10.3 mg/dL D. 12 mg/dL

Ans: A Feedback: To calculate corrected serum calcium, subtract the normal serum albumin level of 4 g/dL from the reported albumin level of 3 g/dL, multiply that value (1) by 0.8 (constant factor) and then add that result (0.8 mg) to the reported serum level of 9 mg/dL. Therefore, 9 + 0.8 = 9.8 mg/dL (corrected value). Note: a constant factor of 0.8 is used because, for every decrease in serum albumin of 1 g/dL below 4 g/dL, the total serum calcium level is underestimated by 0.8 mg/dL.

Which of the following is a clinical manifestation of fluid volume excess (FVE)? Select all that apply. A. Shortness of breath B. Crackles in the lung fields C. Bradycardia D. Decreased blood pressure E. Distended neck veins

Ans: A, B, E Feedback: Clinical manifestations of FVE include distended neck veins, crackles in the lung fields, shortness of breath, increased blood pressure, and tachycardia.

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? A. Hypokalemia B. Hypocalcemia C. Hypercalcemia D. Hyperkalemia

Ans: B FeedbacK: 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. The client's other laboratory findings are within their normal ranges, so the client doesn't have hypernatremia, hypochloremia, or hypokalemia.

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? A. Metabolic alkalosis B. Respiratory acidosis C. Altered blood urea nitrogen (BUN) value D. Extracellular fluid volume deficit

Ans: D Feedback: 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.

A client with a history of anxiety experiences respiratory alkalosis. The nurse measures a respiratory rate of 46 breaths/minute, a heart rate of 110 beats/minute, a blood pressure of 162/90 mm Hg, and a temperature of 98.6° F (37° C). To help correct respiratory alkalosis, the nurse should: A. insert a nasogastric tube (NG) as ordered. B. instruct the client to breathe into a paper bag. C. administer antibiotics as ordered. D. administer acetaminophen as ordered.

Ans: B Feedback: A client with a history of anxiety who experiences respiratory alkalosis should breathe into a paper bag to increase arterial carbon dioxide tension and ease anxiety (which may exacerbate the alkalosis). An NG tube would be indicated for a client with metabolic alkalosis secondary to ingestion of toxic substances; there is no reason to believe that this has occurred. Fever may cause metabolic (not respiratory) alkalosis and would be treated with acetaminophen. A client with sepsis also may have metabolic alkalosis and probably would receive antibiotics; however, this clinical situation doesn't suggest sepsis.

A client with excess fluid volume and hyponatremia is in a comatose state. What are the nursing considerations concerning fluid replacement? A. Correct the sodium deficit rapidly with salt. B. Administer small volumes of a hypertonic solution. C. Monitor the serum sodium for changes hourly. D. Restrict fluids and salt for 24 hours.

Ans: B Feedback: In clients with normal or excess fluid volume, hyponatremia is usually treated effectively by restricting fluid with clients who are not neurologically impaired. When the serum sodium concentration is overcorrected (exceeding 140 mEq/L) too rapidly or in the presence of hypoxia or anoxia, the client can develop neurological symptoms. However, if neurologic symptoms are severe (e.g., seizures, delirium, coma), or if the client has traumatic brain injury, it may be necessary to administer small volumes of a hypertonic sodium solution with the goal of alleviating cerebral edema. Incorrect use of these fluids is extremely dangerous, because 1 L of 3% sodium chloride solution contains 513 mEq (mmol/L) of sodium and 1 L of 5% sodium chloride solution contains 855 mEq (mmol/L) of sodium. The recommendation for hypertonic saline administration in clients with craniocerebral trauma is between 0.10 to 1.0 mL of 3% saline per kilogram of body weight per hour.

An adult client is brought in to the clinic feeling thirsty with dry, sticky mucous membranes; decreased urine output; fever; a rough tongue; and lethargy. The nurse reconciles the client's medication list and notes that salt tablets had been prescribed. What would the nurse do next? A. Be prepared to administer a sodium chloride IV. B. Consider sodium restriction with discontinuation of salt tablets. C. Continue to monitor client with another appointment. D. Be prepared to administer a lactated Ringer's IV.

Ans: B Feedback: The client's symptoms of feeling thirsty with dry, sticky mucous membranes; decreased urine output; fever; a rough tongue; and lethargy suggest hypernatremia. The client needs to be evaluated with serum blood tests soon; a later appointment will delay treatment. It is necessary to restrict sodium intake. Salt tablets and a sodium chloride IV will only worsen this condition. A Lactated Ringer's IV is a hypertonic IV and is not used with hypernatremia. A hypotonic solution IV may be a part of the treatment, but not along with the salt tablets.

A client who is semiconscious presents with restlessness and weakness. The nurse assesses a dry, swollen tongue; body temperature of 99.3 °F; and a urine specific gravity of 1.020. What is the most likely serum sodium value for this client? A. 145 mEq/L B. 165 mEq/L C. 130 mEq/L D. 110 mEq/L

Ans: B Feedback: The normal sodium level is 135- 145 mEq/L (135-145 mmol/L). In hypernatremia, the serum sodium level exceeds 145 mEq/L (145 mmol/L) and the serum osmolality exceeds 300 mOsm/kg (300 mmol/L). The urine specific gravity and urine osmolality are increased as the kidneys attempt to conserve water (provided the water loss is from a route other than the kidneys). Body temperature may increase mildly, but it returns to normal after the hypernatremia is corrected.

A client with nausea, vomiting, and abdominal cramps and distention is admitted to the health care facility. Which test result is most significant? A. Blood urea nitrogen (BUN) level of 29 mg/dl B. Urine specific gravity of 1.025 C. Serum potassium level of 3 mEq/L D. Serum sodium level of 132 mEq/L

Ans: C Feedback: A serum potassium level of 3 mEq/L is below normal, indicating hypokalemia. Because hypokalemia may cause cardiac arrhythmias and asystole, it's the most significant finding. In a client with a potential fluid volume imbalance, such as from vomiting, the other options are expected but none are as life-threatening as hypokalemia. A BUN level of 29 mg/dl indicates slight dehydration. A serum sodium level of 132 mEq/L is slightly below normal but not life-threatening. A urine specific gravity of 1.025 is normal.

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? A. Metabolic acidosis B. Respiratory acidosis C. Metabolic alkalosis D. Respiratory alkalosis

Ans: C Feedback: 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.

Following a unilateral adrenalectomy, a nurse should assess for hyperkalemia as indicated by: A. constipation. B. tremors. C. muscle weakness. D. diaphoresis.

Ans: C Feedback: Muscle weakness, bradycardia, nausea, diarrhea, and paresthesia of the hands, feet, tongue, and face are findings associated with hyperkalemia, which is transient and results from transient hypoaldosteronism when the adenoma is removed. Tremors, diaphoresis, and constipation aren't seen in hyperkalemia.

A client is diagnosed with syndrome of inappropriate antidiuretic hormone (SIADH). The nurse informs the client that the physician will order diuretic therapy and restrict fluid and sodium intake to treat the disorder. If the client doesn't comply with the recommended treatment, which complication may arise? A. Tetany B. Hypovolemic shock C. Cerebral edema D. Severe hyperkalemia

Ans: C Feedback: Noncompliance with treatment for SIADH may lead to water intoxication from fluid retention caused by excessive antidiuretic hormone. This, in turn, limits water excretion and increases the risk for cerebral edema. Hypovolemic shock results from, severe deficient fluid volume; in contrast, SIADH causes excess fluid volume. The major electrolyte disturbance in SIADH is dilutional hyponatremia, not hyperkalemia. Because SIADH doesn't alter renal function, potassium excretion remains normal; therefore, severe hyperkalemia doesn't occur. Tetany results from hypocalcemia, an electrolyte disturbance not associated with SIADH.

The nurse is assigned to care for a client with a serum phosphorus concentration of 5.0 mg/dL (1.61 mmol/L). The nurse anticipates that the client will also experience which electrolyte imbalance? A. Hypermagnesemia B. Hyperchloremia C. Hypocalcemia D. Hyponatremia

Ans: C Feedback: The client is experiencing an elevated serum phosphorus concentration. Hyperphosphatemia is defined as a serum phosphorus that exceeds 4.5 mg/dL (1.45 mmol/L). Because of the reciprocal relationship between phosphorus and calcium, a high serum phosphorus concentration tends to cause a low serum calcium concentration.

The nurse is caring for a client with a serum potassium concentration of 6.0 mEq/L (6.0 mmol/L). The client is ordered to receive oral sodium polystyrene sulfonate and furosemide. What other order should the nurse anticipate giving? A. Increase the rate of the intravenous lactated Ringer solution. B. Change the lactated Ringer solution to 2.5% dextrose. C. Discontinue the intravenous lactated Ringer solution. D. Change the lactated Ringer solution to 3% saline.

Ans: C Feedback: The lactated Ringer intravenous (IV) fluid is contributing to both the fluid volume excess and the hyperkalemia. In addition to the volume of IV fluids contributing to the fluid volume excess, lactated Ringer solution contains more sodium than daily requirements, and excess sodium worsens fluid volume excess. Lactated Ringer solution also contains potassium, which would worsen the hyperkalemia.

The nurse is caring for a client with multiple organ failure and in metabolic acidosis. Which pair of organs is responsible for regulatory processes and compensation? A. Heart and lungs B. Kidney and liver C. Lungs and kidney D. Pancreas and stomach

Ans: C Feedback: The lungs and kidneys facilitate the ratio of bicarbonate to carbonic acid. Carbon dioxide is one of the components of carbonic acid. The lungs regulate carbonic acid levels by releasing or conserving CO2 by increasing or decreasing the respiratory rate. The kidneys assist in acid-base balance by retaining or excreting bicarbonate ions.

What percentage of potassium excreted daily leaves the body by way of the kidneys? A. 40 B. 20 C. 80 D. 60

Ans: C Feedback: To maintain the potassium balance, the renal system must function, because 80% of the potassium excreted daily leaves the body by way of the kidneys. The other numerical values are incorrect.

A nurse is caring for a client in acute renal failure. The nurse should expect hypertonic glucose, insulin infusions, and sodium bicarbonate to be used to treat: A. hypercalcemia. B. hypernatremia. C. hypokalemia. D. hyperkalemia.

Ans: D FeedbacK: Hyperkalemia is a common complication of acute renal failure. It's life-threatening if immediate action isn't taken to reverse it. Administering glucose and regular insulin, with sodium bicarbonate if necessary, can temporarily prevent cardiac arrest by moving potassium into the cells and temporarily reducing serum potassium levels. Hypernatremia, hypokalemia, and hypercalcemia don't usually occur with acute renal failure and aren't treated with glucose, insulin, or sodium bicarbonate.

When caring for a client who has risk factors for fluid and electrolyte imbalances, which assessment finding is the highest priority for the nurse to follow up? A. Weight loss of 4 lb B. Blood pressure 96/53 mm Hg C. Mild confusion D. Irregular heart rate

Ans: D FeedbacK: Irregular heart rate may indicate a potentially life-threatening cardiac dysrhythmia. Potassium, magnesium, and calcium imbalances may cause dysrhythmias. Weight loss is a good indicator of the amount of fluid lost, confusion may occur with dehydration and hyponatremia, and blood pressure is slightly lower than normal (though not life threatening); in each case, following up on potential cardiac dysrhythmias is a higher priority.

A nurse in the Medical ICU has orders to infuse a hypertonic solution into a patient with low blood pressure. This solution will increase the number of dissolved particles in the patient's blood, creating pressure for fluids in the tissues to shift into the capillaries and increase the blood volume. What term or terms are associated with this process? A. Active transport B. Hydrostatic pressure C. Diffusion D. Osmosis and osmolality

Ans: D Feedback: A nurse in the Medical ICU has orders to infuse a hypertonic solution into a patient with low blood pressure. This solution will increase the number of dissolved particles in the patient's blood, creating pressure for fluids in the tissues to shift into the capillaries and increase the blood volume. What term or terms are associated with this process?

The Emergency Department (ED) nurse is caring for a client with a possible acid-base imbalance. The physician has ordered an arterial blood gas (ABG). What is one of the most important indications of an acid-base imbalance that is shown in an ABG? A. PaO2 B. Carbonic acid C. PO2 D. Bicarbonate

Ans: D Feedback: Arterial blood gas (ABG) results are the main tool for measuring blood pH, CO2 content (PaCO2), and bicarbonate. An acid-base imbalance may accompany a fluid and electrolyte imbalance. PaO2 and PO2 are not indications of acid-base imbalance. Carbonic acid levels are not shown in an ABG.

Which of the following is a factor affecting an increase in urine osmolality? A. Fluid volume excess B. Alkalosis C. Myocardial infarction D. Syndrome of inappropriate antidiuretic hormone release (SIADH)

Ans: D Feedback: Factors increasing urine osmolality include SIADH, fluid volume deficit, acidosis, and congestive heart failure. Myocardial infarction typically is not a factor that increases urine osmolality.

The nurse is caring for a client diagnosed with chronic obstructive pulmonary disease (COPD) and experiencing respiratory acidosis. The client asks what is making the acidotic state. The nurse is most correct to identify which result of the disease process that causes the fall in pH? A. The lungs are unable to breathe in sufficient oxygen. B. The lungs are unable to exchange oxygen and carbon dioxide. C. The lungs have ineffective cilia from years of smoking. D. The lungs are not able to blow off carbon dioxide.

Ans: D Feedback: In clients with chronic respiratory acidosis, the client is unable to blow off carbon dioxide leaving in increased amount of hydrogen in the system. The increase in hydrogen ions leads to acidosis. In COPD, the client is able to breathe in oxygen and gas exchange can occur, it is the lungs ability to remove the carbon dioxide from the system. Although individuals with COPD frequently have a history of smoking, cilia is not the cause of the acidosis.

A patient is admitted with a diagnosis of renal failure. The patient complains of "stomach distress" and describes ingesting several antacid tablets over the past 2 days. Blood pressure is 110/70 mm Hg, face is flushed, and the patient is experiencing generalized weakness. Which is the most likely magnesium level associated with the symptoms the patient is having? A. 11 mEq/L B. 1 mEq/L C. 2 mEq/L D. 5 mEq/L

Ans: D Feedback: Magnesium excess (>2.7 mEq/L) is associated with the following symptoms: flushing, hypotension, muscle weakness, drowsiness, hypoactive reflexes, depressed respirations, and cardiac arrest. The respiratory center is depressed when serum magnesium levels exceed 10 mEq/L (5 mmol/L). This is not present in this patient, so the magnesium level is unlikely to be 11 mEq/L. Coma, atrioventricular heart block, and cardiac arrest can occur when the serum magnesium level is greatly elevated and not treated.

A client has been diagnosed with an intestinal obstruction and has a nasogastric tube set to low continuous suction. Which acid-base disturbance is this client at risk for developing? A. Respiratory acidosis B. Respiratory alkalosis C. Metabolic acidosis D. Metabolic alkalosis

Ans: D Feedback: Metabolic alkalosis is a clinical disturbance characterized by a high pH and a high plasma bicarbonate concentration. The most common cause of metabolic alkalosis is vomiting or gastric suction with loss of hydrogen and chloride ions. Gastric fluid has an acid pH, and loss of this acidic fluid increases the alkalinity of body fluids.

Which could be a potential cause of respiratory acidosis? A. Vomiting B. Diarrhea C. Hyperventilation D. Hypoventilation

Ans: D Feedback: Respiratory acidosis is always due to inadequate excretion of CO2, with inadequate ventilation, resulting in elevated plasma CO concentration, which causes increased levels of carbonic acid. In addition to an elevated PaCO2, hypoventilation usually causes a decrease in PaO2.

The nurse is caring for a client with severe diarrhea. The nurse recognizes that the client is at risk for developing which acid-base imbalance? A. Metabolic alkalosis B. Respiratory alkalosis C. Respiratory acidosis D. Metabolic acidosis

Ans: D Feedback: The client is at risk for developing metabolic acidosis. Metabolic acidosis is caused by diarrhea, lower intestinal fistulas, ureterostomies, and use of diuretics; early renal insufficiency; excessive administration of chloride; and the administration of parenteral nutrition without bicarbonate or bicarbonate-producing solutes (e.g., lactate).

The nurse is instructing a client with recurrent hyperkalemia about following a potassium-restricted diet. Which statement by the client indicates the need for additional instruction? A. "I need to check to see whether my cola beverage has potassium in it." B. "I'll drink cranberry juice with my breakfast instead of coffee." C. "Bananas have a lot of potassium in them; I'll stop buying them." D. "I will not salt my food; instead I'll use salt substitute."

Ans: D Feedback: The client should avoid salt substitutes. The nurse must caution clients to use salt substitutes sparingly if they are taking other supplementary forms of potassium or potassium-conserving diuretics. Potassium-rich foods to be avoided include many fruits and vegetables, legumes, whole-grain breads, lean meat, milk, eggs, coffee, tea, and cocoa. Conversely, foods with minimal potassium content include butter, margarine, cranberry juice or sauce, ginger ale, gumdrops or jellybeans, hard candy, root beer, sugar, and honey. Labels of cola beverages must be checked carefully because some are high in potassium and some are not.

A nurse is monitoring a client being evaluated who has a potassium level of 7 mEq/L (mmol/L). Which electrocardiogram changes will the client display? A. elevated ST segment B. prolonged T waves C. shortened PR interval D. peaked T waves

Ans: D Feedback: The earliest changes occur when the serum potassium level is 7 mEq/L (mmol/L). Cardiac tracings include peaked and narrow T waves, ST segment depression, and a shortened QT interval.