Chapter 13: Fluid and Electrolytes: Balance and Disturbance

Which intervention is most appropriate for a client with an arterial blood gas (ABG) of pH 7.5, a partial pressure of arterial carbon dioxide (PaCO2) of 26 mm Hg, oxygen (O2) saturation of 96%, bicarbonate (HCO3-) of 24 mEq/L, and a PaO2 of 94 mm Hg? Administer ordered supplemental oxygen. Administer an ordered decongestant. Instruct the client to breathe into a paper bag. Offer the client fluids frequently.

Instruct the client to breathe into a paper bag. Rationale: The ABG results reveal respiratory alkalosis. The best intervention to raise the PaCO2 level would be to have the client breathe into a paper bag. Administering a decongestant, offering fluids frequently, and administering supplemental oxygen wouldn't raise the lowered PaCO2 level.

The nurse is caring for a client diagnosed with bulimia. The client is being treated for a serum potassium concentration of 2.9 mEq/L (2.9 mmol/L). Which statement made by the client indicates the need for further teaching? "I will be sure to buy frozen vegetables when I grocery shop." "A good breakfast for me will include milk and a couple of bananas." "I can use laxatives and enemas but only once a week." "I will take a potassium supplement daily as prescribed."

"I can use laxatives and enemas but only once a week." Rationale: The client is experiencing hypokalemia, most likely due to the diagnosis of bulimia. Hypokalemia is defined as a serum potassium concentration <3.5 mEq/L (3.5 mmol/L), and usually indicates a deficit in total potassium stores. Clients diagnosed with bulimia frequently suffer increased potassium loss through self-induced vomiting and misuse of laxatives, diuretics, and enemas; thus, the client should avoid laxatives and enemas. Prevention measures may involve encouraging the client at risk to eat foods rich in potassium (when the diet allows), including fruit juices and bananas, melon, citrus fruits, fresh and frozen vegetables, lean meats, milk, and whole grains. If the hypokalemia is caused by abuse of laxatives or diuretics, client education may help alleviate the problem.

The physician has prescribed a hypotonic IV solution for a patient. Which IV solution should the nurse administer? 0.45% sodium chloride 0.9% sodium chloride 5% glucose in water 5% glucose in normal saline solution

0.45% sodium chloride Rationale: Half-strength saline (0.45% sodium chloride) solution is frequently used as an IV hypotonic solution.

Which is considered an isotonic solution? 0.9% normal saline Dextran in normal saline 0.45% normal saline 3% NaCl

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

A 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? 114 mEq/L 130 mEq/L 135 mEq/L 148 mEq/L

114 mEq/L Rationale: 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.

A client weighing 160.2 pounds (72.7 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? 156.0 lbs (70.8 kg) 157.0 lbs (71.2 kg) 158.0 lbs (71.7 kg) 159.0 lbs (72.1 kg)

158.0 lbs (71.7 kg) Rationale: A loss of 0.5 kg, or 1.1 lb, represents a fluid loss of about 500 mL. Therefore, a loss of 1,000 mL would be equivalent to the loss of 2.2 lbs (1 kg), bringing the client's weight to 158.0 lbs (71.7 kg).

A client experiencing a severe anxiety attack and hyperventilating presents to the emergency department. The nurse would expect the client's pH value to be 7.50 7.45 7.35 7.30

7.50 Rationale: The patient is experiencing respiratory alkalosis. Respiratory alkalosis is a clinical condition in which the arterial pH is >7.45 and the PaCO2 is <38 mm Hg. Respiratory alkalosis is always caused by hyperventilation, which causes excessive "blowing off" of CO2 and, hence, a decrease in the plasma carbonic acid concentration. Causes include extreme anxiety, hypoxemia, early phase of salicylate intoxication, gram-negative bacteremia, and inappropriate ventilator settings.

Which of the following measurable urine outputs indicates the client is maintaining adequate fluid intake and balance? A patient with a minimal urine output of 50 mL/hour A patient with a minimal urine output of 20 mL/hour A patient with a minimal urine output of 30 mL/hour A patient with a minimal urine output of 10 mL/hour

A patient with a minimal urine output of 30 mL/hour Rationale: A client with minimal urine output of 30 mL/hour provides the nurse with the information that the patient is maintaining proper fluid balance. Less then 30 mL/hour of urine output indicates dehydration and possible poor kidney function.

Which electrolyte is a major anion in body fluid? Chloride Potassium Sodium Calcium

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

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? Widened QRS wave Flat P wave Elevated U wave Peaked T wave

Elevated U wave Rationale: 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 sign suggests that a client with the syndrome of inappropriate antidiuretic hormone (SIADH) secretion is experiencing complications? Tetanic contractions Jugular vein distention Weight loss Polyuria

Jugular vein distention Rationale: 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).

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? Respiratory acidosis Respiratory alkalosis Metabolic acidosis Metabolic alkalosis

Metabolic alkalosis Rationale: 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.

A nurse is reviewing a report of a client's routine urinalysis. Which value requires further investigation? Specific gravity of 1.02 Urine pH of 3.0 Absence of protein Absence of glucose

Urine pH of 3.0 Rationale: Normal urine pH is 4.5 to 8; therefore, a urine pH of 3.0 is abnormal and requires further investigation. Urine specific gravity normally ranges from 1.010 to 1.025, making this client's value normal. Normally, urine contains no protein, glucose, ketones, bilirubin, bacteria, casts, or crystals. Red blood cells should measure 0 to 3 per high-power field; white blood cells, 0 to 4 per high-power field. Urine should be clear, with color ranging from pale yellow to deep amber.

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? vital signs weight edema intake and output

Weight Rationale: 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 nurse is providing client teaching about the body's plasma pH and the client asks the nurse what is the major chemical regulator of plasma pH. What is the best response by the nurse? renin-angiotensin-aldosterone system bicarbonate-carbonic acid buffer system sodium-potassium pump ADH-ANP buffer system

bicarbonate-carbonic acid buffer system Rationale: The major chemical regulator of plasma pH is the bicarbonate-carbonic acid buffer system. The renin-angiotensin-aldosterone system regulates blood pressure. The sodium-potassium pump regulate homeostasis. The ADH-ANP buffer system regulates water balance in the body.

Early signs of hypervolemia include a decrease in blood pressure. thirst. moist breath sounds. increased breathing effort and weight gain.

increased breathing effort and weight gain. Rationale: Early signs of hypervolemia are weight gain, elevated blood pressure, and increased breathing effort. Eventually, fluid congestion in the lungs leads to moist breath sounds. One of the earliest symptoms of hypovolemia is thirst.

A client with severe hypervolemia is prescribed a loop diuretic and the nurse is concerned with the client experiencing significant sodium and potassium losses. What drug was most likely prescribed? furosemide hydrochlorothiazide metolazone spironolactone

furosemide rationale: Furosemide is the only loop diuretic choice. Hydrochlorothiazide and metolazone are thiazide diuretics that block sodium reabsorption. Spironolactone is a potassium-sparing diuretic that prevents sodium absorption.

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? client's diet is lacking in calcium-rich food products. malignancy is causing the electrolyte imbalance. client has a history of alcohol abuse. client may be developing hyperaldosteronism.

malignancy is causing the electrolyte imbalance. Rationale: 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.

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

muscle weakness. Rationale: 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 with respiratory acidosis is admitted to the intensive care unit for close observation. What client complication associated with respiratory acidosis would the nurse observe? papilledema stroke seizures hyperglycemia

papilledema Rationale: If respiratory acidosis is severe, intracranial pressure may rise, causing papilledema. Stroke and hyperglycemia are not associated with respiratory acidosis. Seizures may complicate respiratory alkalosis, not respiratory acidosis.

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

respiratory alkalosis. Rationale:This client's above-normal pH value indicates alkalosis. The below-normal PaCO2 value indicates acid loss via hyperventilation; this type of acid loss occurs only in respiratory alkalosis. These ABG values wouldn't occur in metabolic acidosis, respiratory acidosis, or metabolic alkalosis.

The nurse notes that a patient's urine osmolality is 980 mOsm/kg. What should the nurse assess as a possible cause of this finding? Diabetes insipidus Acidosis Hyponatremia Fluid volume excess

Acidosis Rationale: Normal urine osmolality is 200 to 800 mOsm/kg, so 980 mOsm/kg is elevated. Acidosis is a factor that increases urine osmolality. Fluid volume excess, diabetes insipidus, and hyponatremia are all factors that decrease urine osmolality.

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? Headache, blood pressure 90/54, dry skin Blood pressure 188/120, nausea, vomiting Confusion, respiratory rate 8 breaths/min, dry skin Clammy skin, blood pressure 86/46, headache

Clammy skin, blood pressure 86/46, headache Rationale: 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.

The nurse is caring for a client in heart failure with signs of hypervolemia. Which vital sign is indicative of the disease process? Low heart rate Elevated blood pressure Rapid respiration Subnormal temperature

Elevated blood pressure Rationale: 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.

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? Continue to monitor client with another appointment. Be prepared to administer a lactated Ringer's IV. Be prepared to administer a sodium chloride IV. Consider sodium restriction with discontinuation of salt tablets.

Consider sodium restriction with discontinuation of salt tablets. Rationale: 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 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? Respiratory acidosis Metabolic alkalosis Extracellular fluid volume deficit Altered blood urea nitrogen (BUN) value

Extracellular fluid volume deficit Rationale: 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? Myasthenia gravis Extreme anxiety Opioid overdose Type 1 diabetes mellitus

Extreme anxiety Rationale: 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.

A client hospitalized for treatment of a pulmonary embolism develops respiratory alkalosis. Which clinical findings commonly accompany respiratory alkalosis? Headache or blurry vision Light-headedness or paresthesia Abdominal pain or diarrhea Hallucinations or tinnitus

Light-headedness or paresthesia Rationale: The client with respiratory alkalosis may complain of light-headedness or paresthesia (numbness and tingling in the arms and legs). Headache, blurry vision, abdominal pain, and diarrhea may accompany respiratory acidosis. Hallucinations and tinnitus rarely are associated with respiratory alkalosis or any other acid-base imbalance.

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? Kidney and liver Heart and lungs Lungs and kidney Pancreas and stomach

Lungs and kidney Rationale: 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.

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 Respiratory acidosis Metabolic alkalosis Respiratory alkalosis

Metabolic acidosis Rationale: 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).