NURS 327 Chapter 13 Fluids and Electrolytes

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 Indicates respiratory alkalosis. The pH level is increased, and the HCO3- and PaCO2 levels are decreased. Normal values are pH 7.35 to 7.45; PaCO2 35 to 45 mm Hg; HCO3- 22 to 26 mEq/L.

Which electrolyte is a major anion in body fluid?

Chloride Chloride is a major anion found in extracellular fluid. Potassium, sodium, and calcium are cations.

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?

I will not salt my food; instead I'll use salt substitute 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 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?

Intravenous furosemide 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.

A client who complains of an "acid stomach" has been taking baking soda (sodium bicarbonate) regularly as a self-treatment. This may place the client at risk for which acid-base imbalance?

Metabolic alkalosis Metabolic alkalosis results in increased plasma pH because of accumulated base bicarbonate or decreased hydrogen ion concentrations. The client's regular use of baking soda (sodium bicarbonate) may create a risk for this condition. Metabolic acidosis refers to decreased plasma pH because of increased organic acids (acids other than carbonic acid) or decreased bicarbonate. Respiratory acidosis, which may be either acute or chronic, is caused by excess carbonic acid. Respiratory alkalosis results from a carbonic acid deficit that occurs when rapid breathing releases more CO2 than necessary with expired air.

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 - Document presenting signs and symptoms - Maintain intake and output records Metabolic alkalosis results in increased plasma pH because of accumulated base bicarbonate or decreased hydrogen ion concentrations. The result is retention of sodium bicarbonate and increased base bicarbonate. Nursing management includes documenting all presenting signs and symptoms to provide accurate baseline data, monitoring laboratory values, comparing ABG findings with previous results (if any), maintaining accurate intake and output records to monitor fluid status, and implementing prescribed medical therapy.

Which of the following is a clinical manifestation of fluid volume excess (FVE)? Select all that apply.

- Crackles in the lung fields - Shortness of breath - Distended neck veins Clinical manifestations of FVE include distended neck veins, crackles in the lung fields, shortness of breath, increased blood pressure, and tachycardia.

The nurse is caring for a client who was admitted with fluid volume excess (FVE). Which nursing assessments should the nurse include in the ongoing monitoring of the client? Select all that apply.

- Nutritional status and diet - Blood pressure, heart rate, and rhythm - Intake and output, urine volume, and color - Skin assessment for edema and turgor To assess for FVE the nurse measures blood pressure, heart rate and rhythm, and breath sounds; inspects the skin to look for edema and turgor; and inspects neck veins. Intake and output, daily weight, urine volume and color, dyspnea, and thirst are assessments that will assist the nurse in identifying improvement or worsening of the fluid volume excess. In addition, the nurse will be able to identify potential fluid volume deficit from overtreatment of the fluid volume excess. Treatment of FVE typically involves dietary restriction of sodium.

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.)

- Tachypnea - Oliguria - Tachycardia Hypovolemia, or fluid volume deficit, is indicated by decreased, not increased, blood pressure (hypotension), oliguria, tachycardia (not bradycardia), and tachypnea.

A client weighing 160 pounds (72.6 kg), who has been diagnosed with hypovolemia, is weighed every day. The health care provider asked to be notified if the client loses 1,000 mL of fluid in 24 hours. What weight would be consistent with this amount of fluid loss?

158 lbs (71.7 kg) A loss of 0.5 kg, or 1 lb, represents a fluid loss of about 500 mL. Therefore, a loss of 1,000 mL would be equivalent to the loss of 2 lbs (0.9 kg), bringing the client's weight to 158 lbs (71.7 kg).

A nurse correctly identifies a urine specimen with a pH of 4.3 as being which type of solution?

Acidic Normal urine pH is 4.5 to 8.0; a value of 4.3 reveals acidic urine pH. A pH above 7.0 is considered an alkaline or basic solution. A pH of 7.0 is considered neutral.

A client with excess fluid volume and hyponatremia is in a comatose state. What are the nursing considerations concerning fluid replacement?

Administer small volumes of a hypertonic solution 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.

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?

Bicarbonate 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 is an insensible mechanism of fluid loss?

Breathing Loss of fluid from sweat or diaphoresis is referred to as insensible loss because it is unnoticeable and immeasurable. Losses from urination and bowel elimination are measurable. Nausea does not result in fluid loss, however if the client would develop emesis ( vomiting) this would be considered loss of body fluids and would need measured.

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?

Cerebral edema 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 caring for a client being treated with isotonic IV fluid for hypernatremia. What complication of hypernatremia should the nurse continuously monitor for?

Cerebral edema 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.

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?

Consider sodium restriction with discontinuation of salt tablets. 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.

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?

Discontinue the intravenous lactated Ringer solution. 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 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.

Which laboratory result does the nurse identify as a direct result of the client's hypovolemic status with hemoconcentration?

Elevated hematocrit level 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.

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.

Before seeing a newly assigned client with respiratory alkalosis, a nurse quickly reviews the client's medical history. Which condition is a predisposing factor for respiratory alkalosis?

Extreme anxiety Extreme anxiety may lead to respiratory alkalosis by causing hyperventilation, which results in excessive carbon dioxide (CO2) loss. Other conditions that may set the stage for respiratory alkalosis include fever, heart failure, injury to the brain's respiratory center, overventilation with a mechanical ventilator, pulmonary embolism, and early salicylate intoxication. Type 1 diabetes may lead to diabetic ketoacidosis; the deep, rapid respirations occurring in this disorder (Kussmaul respirations) don't cause excessive CO2 loss. Myasthenia gravis and opioid overdose suppress the respiratory drive, causing CO2 retention, not CO2 loss; this may lead to respiratory acidosis, not alkalosis.

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?

Hypocalcemia 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.

Which could be a potential cause of respiratory acidosis?

Hypoventilation 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.

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?

Irregular heart rate 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.

Which sign suggests that a client with the syndrome of inappropriate antidiuretic hormone (SIADH) secretion is experiencing complications?

Jugular vein distention 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).

With which condition should the nurse expect that a decrease in serum osmolality will occur?

Kidney failure 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.

A client with cancer is being treated on the oncology unit for bilateral breast cancer. The client is undergoing chemotherapy. The nurse notes the client's serum calcium concentration is 12.3 mg/dL (3.08 mmol/L). Given this laboratory finding, the nurse should suspect that the

Malignancy is causing the electrolyte imbalance The client's laboratory findings indicate hypercalcemia. Hypercalcemia is defined as a calcium concentration >10.2 mg/dL (>2.6 mmol/L).The most common causes of hypercalcemia are malignancies and hyperparathyroidism. Malignant tumors can produce hypercalcemia through a variety of mechanisms. The client's calcium level is elevated; there is no indication that the client's diet is lacking in calcium-rich food products. Hyperaldosteronism is not associated with a calcium imbalance. Alcohol abuse is associated with hypocalcemia.

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?

Metabolic acidosis 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).

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?

Metabolic alkalosis 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.

Oncotic pressure refers to the

Osmotic pressure exerted by proteins Oncotic pressure is a pulling pressure exerted by proteins such as albumin. Osmolality refers to the number of dissolved particles contained in a unit of fluid. Osmotic diuresis occurs when urine output increases as a result of excretion of substances such as glucose. Osmotic pressure is the amount of pressure needed to stop the flow of water by osmosis.

Following a unilateral adrenalectomy, a nurse should assess for hyperkalemia as indicated by:

Muscle Weakness 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.

The nurse is assigned a client with calcium level of 4.0 mg/dL. Which system assessment would the nurse ask detailed questions?

Neurological system A client with a calcium level of 4.0 mg/dL has hypocalcemia. The nurse closely monitors the client with hypocalcemia for neurological manifestations such as tetany, seizures, and spasms. If the calcium level continues to decrease, seizure precautions are necessary. Cardiac dysrhythmias and airway obstruction may also occur.

A client with pancreatic cancer has the following blood chemistry profile: Glucose, fasting: 204 mg/dl; blood urea nitrogen (BUN): 12 mg/dl; Creatinine: 0.9 mg/dl; Sodium: 136 mEq/L; Potassium: 2.2 mEq/L; Chloride: 99 mEq/L; CO2: 33 mEq/L. Which result should the nurse identify as critical and report immediately?

Potassium The nurse should identify potassium: 2.2 mEq/L as critical because a normal potassium level is 3.5 to 5.0 mEq/L. Severe hypokalemia can cause cardiac and respiratory arrest, possibly leading to death. Hypokalemia also depresses the release of insulin and results in glucose intolerance. The glucose level is above normal (normal is 75 to 110 mg/dl) and the chloride level is a bit low (normal is 100 to 110 mEq/L). Although these levels should be reported, neither is life-threatening. The BUN (normal is 8 to 26 mg/dl) and creatinine (normal is 0.8 to 1.4 mg/dl) are within normal range.

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?

Provide oral care every 2-3 hours. 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.

A client with chronic renal failure has a serum potassium level of 6.8 mEq/L. What should the nurse assess first?

Pulse 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 caring for a client admitted with a diagnosis of exacerbation of myasthenia gravis. Upon assessment of the client, the nurse notes the client has severely depressed respirations. The nurse would expect to identify which acid-base disturbance?

Respiratory acidosis Respiratory acidosis is always from inadequate excretion of CO2 with inadequate ventilation, resulting in elevated plasma CO2 concentrations. Respiratory acidosis can occur in diseases that impair respiratory muscles such as myasthenia gravis.

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?

Restricting fluids to 800 ml/day 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.

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?

Send the client for a chest x-ray 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 with nausea, vomiting, and abdominal cramps and distention is admitted to the health care facility. Which test result is most significant?

Serum potassium level of 3 mEq/L 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.

Which medication does the nurse anticipate administering to antagonize the effects of potassium on the heart for a patient in severe metabolic acidosis?

Sodium bicarbonate 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.

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.

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.

Tented T wave 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 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?

The lungs are not able to blow off carbon dioxide 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 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:

hyperkalemia 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.

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?

peaked T waves 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.