8: Fluid & Electrolytes 2023 with complete solution questions and answers

A patient has newly diagnosed hyperparathyroidism. What should the nurse expect to find during an assessment at the beginning of the nursing shift? A. Lethargy and constipation from hypercalcemia B. Positive Trousseau's sign from hypercalcemia C. Lethargy and constipation from hypocalcemia D. Positive Trousseau's sign from hypocalcemia Answer: A Rationale: Parathyroid hormone (PTH) shifts calcium from the bones into the extracellular fluid (ECF). Excessive PTH causes hypercalcemia, which is manifested by lethargy and constipation. A positive Trousseau's sign is characteristic of hypocalcemia rather than hypercalcemia. Answers that indicate hypocalcemia are not correct, because PTH moves calcium into the ECF. A patient injured in an earthquake today when a wall fell on his legs received 9 units of blood an hour ago because he was hemorrhaging. Which laboratory value should the nurse check first when the report returns? A. Serum sodium B. Serum potassium C. Serum total calcium D. Serum magnesium Answer: B Rationale: The patient has two major risk factors for hyperkalemia: massive sudden cell death from a crushing injury (potassium shift from cells into the extracellular fluid) and massive blood transfusion (rapid potassium intake). Although massive blood transfusion may cause calcium and magnesium ions to bind to citrate in the blood, thereby decreasing the physiological availability of those ions, it does not decrease the total calcium or magnesium laboratory measurements. Clinically significant changes in serum sodium are the least likely in this patient. A patient has a tumor that secretes excessive antidiuretic hormone (ADH). He is confused and lethargic. His partner wants to know how a change in blood sodium can cause these symptoms. What should the nurse teach the patient's partner? A. Decreased sodium in the blood causes the blood volume to decrease so that not enough oxygen reaches the brain. B. Decreased sodium in the blood causes brain cells to swell so that they do not work as effectively. C. Increased sodium in the blood causes the blood volume to increase so that too much oxygen reaches the brain. D. Increased sodium in the blood causes brain cells to shrivel so that they do not work as effectively. Answer: B Rationale: The normal action of ADH is renal reabsorption of water, which dilutes the blood. Excessive ADH causes hyponatremia, which is manifested by a decreased level of consciousness because the osmotic shift of water into the brain cells impairs their function. Hyponatremia does not decrease the blood volume. Answers that include increased sodium in the blood are incorrect because ADH excess causes hyponatremia rather than hypernatremia. A patient has acute gastroenteritis with watery diarrhea. Which statement by this patient would indicate that the nurse's teaching has been effective? A. "I should drink a lot of tap water today." B. "I need to take more calcium tablets today." C. "I should avoid fruits with potassium in them." D. "I need to drink liquids with some sodium in them." Answer: D Rationale: Sodium-containing fluids are removed from the body by acute diarrhea and must be replaced to prevent an extracellular fluid volume (ECV) deficit. Drinking tap water will not prevent ECV deficit from diarrhea, because tap water does not contain enough sodium to hold the water in the extracellular compartment. Taking calcium tablets is an incorrect answer because hypocalcemia is characteristic of chronic diarrhea rather than acute diarrhea. Restricting fruits is an incorrect answer because diarrhea increases the potassium output and the potassium intake should be increased to balance it. The home health nurse should assess a patient who has chronic diarrhea for which fluid and electrolyte imbalances? (select all that apply) A. Extracellular fluid volume (ECV) excess B. Extracellular fluid volume (ECV) deficit C. Hypokalemia D. Hyperkalemia E. Hypocalcemia F. Hypercalcemia Answer: B, C, E Rationale: Chronic diarrhea has a high risk of causing ECV deficit, hypokalemia, and hypocalcemia because it increases the fecal output of sodium-containing fluid, potassium, and calcium. Unless the intake of these substances increases appropriately, imbalances will occur. Excesses of ECV, potassium, and calcium are not likely, because the ECV, potassium, and calcium are being removed from the body. The nurse is admitting an older adult with decompensated congestive heart failure. The nursing assessment reveals adventitious lung sounds, dyspnea, and orthopnea. The nurse should question which doctors order? a. Intravenous (IV) 500 mL of 0.9% NaCl at 125 mL/hr b. Furosemide (Lasix) 20 mg PO now c. Oxygen via face mask at 8 L/min d. KCl 20 mEq PO two times per day ANS: A (A patient with decompensated heart failure has extracellular fluid volume (ECV) excess. The IV of 0.9% NaCl is normal saline, which should be questioned because it would expand ECV and place an additional load on the failing heart. Diuretics such as furosemide are appropriate to decrease the ECV during heart failure. Increasing the potassium intake with KCl is appropriate, because furosemide increases potassium excretion. Oxygen administration is appropriate in this situation of near pulmonary edema from ECV excess.) The nurse assessed four patients at the beginning of the shift. Which finding should the nurse report most urgently to the physician? a. Swollen ankles in patient with compensated heart failure b. Positive Chvosteks sign in patient with acute pancreatitis c. Dry mucous membranes in patient taking a new diuretic d. Constipation in patient who has advanced breast cancer ANS: B (Positive Chvosteks sign indicates increased neuromuscular excitability, which can progress to dangerous laryngospasm or seizures and thus needs to be reported first. The other assessment findings are less urgent and need further assessment. Bilateral ankle edema is a sign of ECV excess, and follow-up is needed, but the situation is not immediately life-threatening. Dry mucous membranes in a patient taking a diuretic may be associated with ECV deficit; however, additional assessments of ECV deficit are required before reporting to the physician. Constipation has many causes, including hypercalcemia and opioid analgesics, and it needs action, but not as urgently as a positive Chvosteks sign.) The nurse is assessing a patient before hanging an IV solution of 0.9% NaCl with KCl in it. Which assessment finding should cause the nurse to hold the IV solution and contact the physician? a. Weight gain of 2 pounds since last week b. Dry mucous membranes and skin tenting c. Urine output 8 mL/hr d. Blood pressure 98/58 ANS: C (Administering IV potassium to a patient who has oliguria is not safe, because potassium intake faster than potassium output can cause hyperkalemia with dangerous cardiac dysrhythmias. Dry mucous membranes, skin tenting, and blood pressure 98/58 are consistent with the need for IV 0.9% NaCl. Weight gain of 2 pounds in a week does not necessarily indicate fluid overload, because it can be from increased nutritional intake. Only an overnight weight gain indicates a fluid gain.) At change-of-shift report, the nurse learns the medical diagnoses for four patients. Which patient should the nurse assess most carefully for development of hyponatremia? a. Vomiting all day and not replacing any fluid b. Tumor that secretes excessive antidiuretic hormone (ADH) c. Tumor that secretes excessive aldosterone d. Tumor that destroyed the posterior pituitary gland ANS: B (ADH causes renal reabsorption of water, which dilutes the body fluids. Excessive ADH thus causes hyponatremia. Excessive aldosterone causes ECV excess rather than hyponatremia. The posterior pituitary gland releases ADH; lack of ADH causes hypernatremia. Vomiting without fluid replacement causes ECV deficit and hypernatremia.) The patient is receiving tube feedings due to a jaw surgery. What change in assessment findings should prompt the nurse to request an order for serum sodium concentration? a. Development of ankle or sacral edema b. Increased skin tenting and dry mouth c. Postural hypotension and tachycardia d. Decreased level of consciousness ANS: D (Tube feedings pose a risk for hypernatremia unless adequate water is administered between tube feedings. Hypernatremia causes the level of consciousness to decrease. The serum sodium concentration is a laboratory measure for osmolality imbalances, not ECV imbalances. Edema is a sign of ECV excess, not hypernatremia. Skin tenting, dry mouth, postural hypotension, and tachycardia all can be signs of ECV deficit.) The patient with which diagnosis should have the highest priority for teaching regarding foods that are high in magnesium? a. Severe hemorrhage b. Diabetes insipidus c. Oliguric renal disease d. Adrenal insufficiency ANS: C (When renal excretion is decreased, magnesium intake must be decreased also, to prevent hypermagnesemia. The other conditions are not likely to require adjustment of magnesium intake.) The patients laboratory report today indicates severe hypokalemia, and the nurse has notified the physician. Nursing assessment indicates that heart rhythm is regular. What is the most important nursing intervention for this patient now? a. Raise bed side rails due to potential decreased level of consciousness and confusion. b. Examine sacral area and patients heels for skin breakdown due to potential edema. c. Establish seizure precautions due to potential muscle twitching, cramps, and seizures. d. Institute fall precautions due to potential postural hypotension and weak leg muscles. ANS: D (Hypokalemia can cause postural hypotension and bilateral muscle weakness, especially in the lower extremities. Both of these increase the risk of falls. Hypokalemia does not cause edema, decreased level of consciousness, or seizures.) The home health nurse has an acute immunodeficiency syndrome (AIDS) patient who has chronic diarrhea. Which assessments should the nurse use to detect the fluid and electrolyte imbalances for which the patient has high risk? (Select all that apply.) a. Bilateral ankle edema b. Weaker leg muscles than usual c. Postural blood pressure and heart rate d. Positive Trousseaus sign e. Flat neck veins when upright f. Decreased patellar reflexes ANS: B, C, D (Chronic diarrhea has high risk of causing ECV deficit, hypokalemia, hypocalcemia, and hypomagnesemia because it increases fecal excretion of sodium-containing fluid, potassium, calcium, and magnesium. Appropriate assessments include postural blood pressure and heart rate for ECV deficit; weaker leg muscles than usual for hypokalemia; and positive Trousseaus sign for hypocalcemia and hypomagnesemia. Bilateral ankle edema is a sign of ECV excess, which is not likely with chronic diarrhea. Flat neck veins when upright is a normal finding. Decreased patellar reflexes is associated with hypermagnesemia, which is not likely with chronic diarrhea.) The patient has recent bilateral, above-the-knee amputations and has developed C. difficile diarrhea. What assessments should the nurse use to detect ECV deficit in this patient? (Select all that apply.) a. Test for skin tenting. b. Measure rate and character of pulse. c. Measure postural blood pressure and heart rate. d. Check Trousseaus sign. e. Observe for flatness of neck veins when upright. f. Observe for flatness of neck veins when supine. ANS: A, B, F (ECV deficit is characterized by skin tenting; rapid, thready pulse; and flat neck veins when supine, which can be assessed in this patient. Although ECV deficit also causes postural blood pressure drop with tachycardia, this assessment is not appropriate for a patient with recent bilateral, above-the-knee amputations. Trousseaus sign is a test for increased neuromuscular excitability, which is not characteristic of ECV deficit. Flat neck veins when upright is a normal finding.)