MedSurg Chapter 13
hypotonic solution
Solute concentration is less than that inside the cell; cell gains water
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 can use laxatives and enemas but only once a week."
Which solution is hypotonic?
0.45% NaCl
A client is to receive hypotonic IV solution in order to provide free water replacement. Which solution does the nurse anticipate administering?
0.45% NaCl Rationale: Half-strength saline (0.45%) is hypotonic. Hypotonic solutions are used to replace cellular fluid because it is hypotonic compared with plasma. Another is to provide free water to excrete body wastes. At times, hypotonic sodium solutions are used to treat hypernatremia and other hyperosmolar conditions. Lactated Ringer solution and normal saline (0.9% NaCl) are isotonic. A solution that is 5% NaCl is hypertonic.
Which is considered an isotonic solution?
0.9% normal saline
The nurse is caring for four clients on a medical unit. The nurse is most correct to review which client's laboratory reports first for an electrolyte imbalance?
A 52-year-old with diarrhea
isotonic solution
A solution in which the concentration of solutes is essentially equal to that of the cell which resides in the solution
Which is the most common cause of symptomatic hypomagnesemia?
Alcoholism
Which of the following is the most common cause of symptomatic hypomagnesemia in the United States?
Alcoholism
The nurse has been assigned to care for various clients. Which client is at the highest risk for a fluid and electrolyte imbalance?
An 82-year-old client who receives all nutrition via tube feedings and whose medications include carvedilol and torsemide. Rationale: The 82-year-old client has three risk factors: advanced age, tube feedings, and diuretic usage (torsemide). This client has the highest risk for fluid and electrolyte imbalances. The 45-year-old client has the risk factor of surgery, the 79-year-old client has the risk factor of advanced age, and the 66-year-old client has the risk factors of age and the bile drain, but none of these are the client at the highest risk.
A patient complains of tingling in the fingers as well as feeling depressed. The nurse assesses positive Trousseau's and Chvostek's signs. Which decreased laboratory results does the nurse observe when the patient's laboratory work has returned?
Calcium
Air embolism is a potential complication of IV therapy. The nurse should be alert to which clinical manifestation associated with air embolism?
Chest pain
osmosis
Diffusion of water through a selectively permeable membrane
What foods can the nurse recommend for the patient with hypokalemia?
Fruits such as bananas and apricots
A client with severe hypervolemia is prescribed a loop diuretic. The nurse knows that this drug can cause a significant loss of sodium and has to be carefully monitored. Which of the following drugs is most likely the one that was prescribed?
Furosemide
A nurse is caring for a client with metastatic breast cancer who is extremely lethargic and very slow to respond to stimuli. The laboratory report indicates a serum calcium level of 12.0 mg/dl, a serum potassium level of 3.9 mEq/L, a serum chloride level of 101 mEq/L, and a serum sodium level of 140 mEq/L. Based on this information, the nurse determines that the client's symptoms are most likely associated with which electrolyte imbalance?
Hypercalcemia
Which of the following electrolyte imbalances occur with adrenal insufficiency?
Hyperkalemia
The nurse is conducting a lecture on the difference between hypovolemia and dehydration. When completing a verbal comparison, which point needs clarified?
In dehydration, only extracellular is depleted.
A client hospitalized for treatment of a pulmonary embolism develops respiratory alkalosis. Which clinical findings commonly accompany respiratory alkalosis?
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). Nausea, vomiting, 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 patient with diabetes type I who is having severe vomiting and diarrhea. What condition that exhibits blood values with a low pH and a low plasma bicarbonate concentration should the nurse assess for?
Metabolic acidosis
Your client's lab values are sodium 166 mEq/L, potassium 5.0 mEq/L, chloride 115 mEq/L, and bicarbonate 35 mEq/L. What condition is this client likely to have, judging by anion gap?
Metabolic acidosis
A priority nursing intervention for a client with hypervolemia involves which of the following?
Monitoring respiratory status for signs and symptoms of pulmonary complications.
The nurse is adding the intake and output results for a client diagnosed with dehydration. The nurse notes a 24-hour intake of 1500 mL/day between oral fluids and intravenous solutions. The output total is calculated as 2800 mL/day from urine output, emesis, and Hemovac drainage. Which nursing action is best to maintain an acceptable fluid balance?
Offer a prescribed antiemetic medication.
Which is a correct route of administration for potassium?
Oral Rationale: Potassium may be administered through the oral route. Potassium is never administered by IV push or intramuscularly to avoid replacing potassium too quickly. Potassium is not administered subcutaneously.
The calcium concentration in the blood is regulated by which mechanism?
Parathyroid hormone (PTH) Rationale: The serum calcium concentration is controlled by PTH and calcitonin. The thyroid hormone, adrenal gland, or androgens do not regulate the calcium concentration in the blood.
Which electrolyte is a major cation in body fluid?
Potassium
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
Which condition leads to chronic respiratory acidosis in older adults?
Thoracic skeletal change Rationale: 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.
Treatment of FVE involves dietary restriction of sodium. Which of the following food choices would be part of a low-sodium diet, mild restriction (2 to 3 g/day)?
Three ounces of light or dark meat chicken, 1 cup of spaghetti and a garden salad
A patient is diagnosed with hypocalcemia. The nurse advises the patient and his family to immediately report the most characteristic manifestation. What is the most characteristic manifestation?
Tingling or twitching sensation in the fingers
A nurse is reviewing a report of a client's routine urinalysis. Which value requires further investigation?
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.
Clients diagnosed with hypervolemia should avoid sweet or dry food because it
increases the client's desire to consume fluid. Rationale: 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.
To confirm an acid-base imbalance, it is necessary to assess which findings from a client's arterial blood gas (ABG) results? Select all that apply.
pH PaCO2 HCO3
When evaluating arterial blood gases (ABGs), which value is consistent with metabolic alkalosis?
pH 7.48
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
The nurse is analyzing the arterial blood gas (ABG) results of a client diagnosed with severe pneumonia. Which of the following ABG results indicates respiratory acidosis? Which of the following arterial blood gas results would be consistent with metabolic alkalosis?
pH: 7.20, PaCO2: 65 mm Hg, HCO3-: 26 mEq/L
A client admitted with acute anxiety has the following arterial blood gas (ABG) values: pH, 7.55; partial pressure of arterial oxygen (PaO2), 90 mm Hg; partial pressure of arterial carbon dioxide (PaCO2), 27 mm Hg; and bicarbonate (HCO3-), 24 mEq/L. Based on these values, the nurse suspects:
respiratory alkalosis
A nurse reviews the arterial blood gas (ABG) values of a client admitted with pneumonia: pH, 7.51; PaCO2, 28 mm Hg; PaO2, 70 mm Hg; and HCO3--, 24 mEq/L. What do these values indicate?
respiratory alkalosis
tonicity
the ability of a surrounding solution to cause a cell to gain or lose water
A nurse is conducting an initial assessment on a client with possible tuberculosis. Which assessment finding indicates a risk factor for tuberculosis?
the client had a liver transplant 2 years ago
hydrostatic pressure
the pressure within a blood vessel that tends to push water out of the vessel
diffusion
the process by which solutes move from an area of high concentration to one of low concentration
Which nerve is implicated in the Chvostek's sign?
Facial
The nurse is assessing residents at a summer picnic at the nursing facility. The nurse expresses concern due to the high heat and humidity of the day. Although the facility is offering the residents plenty of fluids for fluid maintenance, the nurse is most concerned about which?
Insensible fluid loss
The nurse is reviewing client lab work for a critical lab value. Which value is called to the physician for additional orders?
Potassium: 5.8 mEq/L
A client with a suspected overdose of an unknown drug is admitted to the emergency department. Arterial blood gas values indicate respiratory acidosis. What should the nurse do first?
Prepare to assist with ventilation.
A nurse correctly identifies a urine specimen with a pH of 4.3 as being which type of solution?
acidic
Which is an insensible mechanism of fluid loss?
breathing
osmolality
number of osmoles of solute per kilogram of water
The physician has prescribed a hypotonic IV solution for a patient. Which IV solution should the nurse administer?
0.45% sodium chloride
A group of nursing students are studying for a test over acid-base imbalance. One student asks another what the major chemical regulator of plasma pH is. What should the second student respond?
Bicarbonate-carbonic acid buffer system
The nurse is caring for a client with laboratory values indicating dehydration. Which clinical symptom is consistent with the dehydration?
Dark, concentrated urine
A client was admitted to the hospital unit after 2 days of vomiting and diarrhea. The client's spouse became alarmed when the client demonstrated confusion and elevated temperature, and reported "dry mouth." The nurse suspects the client is experiencing which condition?
Dehydration
A client was admitted to the unit with a diagnosis of hypovolemia. When it is time to complete discharge teaching, which of the following will the nurse teach the client and family? Select all that apply.
Drink at least eight glasses of fluid each day. Drink water as an inexpensive way to meet fluid needs. Respond to thirst
An elderly client takes 40 mg of Lasix twice a day. Which electrolyte imbalance is the most serious adverse effect of diuretic use?
Hypokalemia Rationale: Hypokalemia (potassium level below 3.5 mEq/L) usually indicates a defict in total potassium stores. Potassium-losing diuretics, such as loop diuretics, can induce hypokalemia.
Oral intake is controlled by the thirst center, located in which of the following cerebral areas?
Hypothalamus
Which intervention is most appropriate for a client with an arterial blood gas (ABG) of pH 7.5, a partial pressure of arterial carbon dioxide (PaCO2) of 26 mm Hg, oxygen (O2) saturation of 96%, bicarbonate (HCO3-) of 24 mEq/L, and a PaO2 of 94 mm Hg?
Instruct 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.
A 64-year-old client is brought in to the clinic with thirsty, dry, sticky mucous membranes, decreased urine output, fever, a rough tongue, and lethargy. Serum sodium level is above 145 mEq/L. Should the nurse start salt tablets when caring for this client?
No sodium intake should be restricted
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 Rationale: 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.
Which of the following arterial blood gas results would be consistent with metabolic alkalosis?
Serum bicarbonate of 28 mEq/L
Which of the following electrolytes is the primary determinant of extracellular fluid (ECF) osmolality?
Sodium
hypertonic solution
Solute concentration is greater than that inside the cell; cell loses water`
To compensate for decreased fluid volume (hypovolemia), the nurse can anticipate which response by the body?
Tachycardia Rationale: Fluid volume deficit, or hypovolemia, occurs when the loss of extracellular fluid exceeds the intake of fluid. Clinical signs include oliguia, rapid heart rate, vasoconstriction, cool and clammy skin, and muscle weakness. The nurse monitors for rapid, weak pulse and orthostatic hypotension.
ascites
a type of edema in which fluid accumulates in the peritoneal cavity
alkalosis
an acid-base imbalance characterized by a reduction in H+ concentration (increased blood pH) (A high arterial pH with increased bicarbonate concentration is called metabolic alkalosis; a high arterial pH due to reduced PCO2 is called respiratory alkalosis.)
acidosis
an acid-base imbalance characterized by an increase in H+ concentration (decreased blood pH) (A low arterial pH due to reduced bicarbonate concentration is called metabolic acidosis; a low arterial pH due to increased PCO2 is called respiratory acidosis.)
A client is taking spironolactone to control hypertension. The client's serum potassium level is 6 mEq/L. What is the nurse's priority during assessment?
electrocardiogram(ECG) results Rationale: Although changes in all these findings are seen in hyperkalemia, ECG results should take priority because changes can indicate potentially lethal arrhythmias such as ventricular fibrillation. It wouldn't be appropriate to assess the client's neuromuscular function, bowel sounds, or respiratory rate for effects of hyperkalemia.
Your client has a diagnosis of hypervolemia. What would be an important intervention that you would initiate?
limit sodium and water intake
homeostasis
maintenance of a constant internal equilibrium in a biologic system that involves positive and negative feedback mechanisms
Following a unilateral adrenalectomy, a nurse should assess for hyperkalemia as indicated by:
muscle weakness
A client with Guillain-Barré syndrome develops respiratory acidosis as a result of reduced alveolar ventilation. Which combination of arterial blood gas (ABG) values confirms respiratory acidosis?
pH, 7.25; PaCO2 50 mm Hg rationale: In respiratory acidosis, ABG analysis reveals an arterial pH below 7.35 and partial pressure of arterial carbon dioxide (PaCO2) above 45 mm Hg. Therefore, the combination of a pH value of 7.25 and a PaCO2 value of 50 mm Hg confirms respiratory acidosis. A pH value of 7.5 with a PaCO2 value of 30 mm Hg indicates respiratory alkalosis. A ph value of 7.40 with a PaCO2 value of 35 mm Hg and a pH value of 7.35 with a PaCO2 value of 40 mm Hg represent normal ABG values, reflecting normal gas exchange in the lungs.
active transport
physiologic pump that moves fluid from an area of lower concentration to one of higher concentration; requires adenosine triphosphate for energy
A client recovering from an acute asthma attack 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:
instruct the client to breathe into a paper bag. Rationale: A client recovering from an acute asthma attack 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.
osmolarity
number of osmoles per liter of solution
A client comes to the emergency department with status asthmaticus. His respiratory rate is 48 breaths/minute, and he is wheezing. An arterial blood gas analysis reveals a pH of 7.52, a partial pressure of arterial carbon dioxide (PaCO2) of 30 mm Hg, PaO2 of 70 mm Hg, and bicarbonate (HCO3??') of 26 mEq/L. What disorder is indicated by these findings?
Respiratory alkalosis Rationale: Respiratory alkalosis results from alveolar hyperventilation. It's marked by a decrease in PaCO2 to less than 35 mm Hg and an increase in blood pH over 7.45. Metabolic acidosis is marked by a decrease in HCO3? to less than 22 mEq/L, and a decrease in blood pH to less than 7.35. In respiratory acidosis, the pH is less than 7.35 and the PaCO2 is greater than 45 mm Hg. In metabolic alkalosis, the HCO3? is greater than 26 mEq/L and the pH is greater than 7.45.
A client has been admitted to the hospital unit with signs and symptoms of hypovolemia; however, the client has not lost weight. The client exhibits a localized enlargement of her abdomen. What condition could the client be presenting?
third-spacing Rationale: Third-spacing describes the translocation of fluid from the intravascular or intercellular space to tissue compartments, where it becomes trapped and useless. The client manifests signs and symptoms of hypovolemia with the exception of weight loss. There may be signs of localized enlargement of organ cavities (such as the abdomen) if they fill with fluid, a condition referred to as ascites. Pitting edema occurs when indentations remain in the skin after compression. Anascara is another term for generalized edema, or brawny edema, in which the interstitial spaces fill with fluid. Hypovolemia (fluid volume deficit) refers to a low volume of extracellular fluid.
You are caring for a 72-year-old client who has been admitted to your unit for a fluid volume imbalance. You know which of the following is the most common fluid imbalance in older adults?
Dehydration