NUR 170 Exam 1: Med Surg - Galen College of Nursing
Updated and Latest Questions and Correct Answers with
Rationale
1. A patient presents with a serum potassium level of 6.2 mEq/L. Which medication should the nurse
anticipate administering first to stabilize the cardiac membrane?
A. Sodium Polystyrene Sulfonate (Kayexalate)
B. Regular Insulin and Dextrose 50%
C. Calcium Gluconate
D. Furosemide (Lasix)
Correct Answer: C
Rationale: Calcium gluconate is administered to stabilize the cardiac cell membrane and prevent life-
threatening arrhythmias in severe hyperkalemia. While insulin and dextrose help shift potassium into
cells, they do not stabilize the heart directly. Sodium polystyrene sulfonate is used for actual removal of
potassium but takes longer to act. Furosemide promotes potassium excretion through the kidneys but is
not the fastest emergency stabilization method. The nurse must prioritize cardiac protection before
focusing on lowering the total potassium level.
2. During the preoperative assessment, a patient reports a family history of high fever and muscle rigidity
during surgery. Which condition should the nurse suspect?
A. Anaphylactic reaction
B. Hypovolemic shock
C. Postoperative ileus
D. Malignant hyperthermia
,Correct Answer: D
Rationale: Malignant hyperthermia is a rare but life-threatening genetic disorder triggered by certain
volatile anesthetic gases and succinylcholine. The primary clinical signs include a rapid rise in body
temperature and severe muscle contractions or rigidity. A family history is a significant risk factor that
necessitates immediate communication with the surgical team. If triggered, the emergency treatment
involves the administration of dantrolene sodium to stop muscle metabolism. Preoperative identification
is critical for planning a safe anesthetic approach for the patient.
3. A nurse is caring for a patient with a phosphorus level of 1.8 mg/dL. Which electrolyte imbalance is most
commonly associated with this finding?
A. Hyperkalemia
B. Hypocalcemia
C. Hypercalcemia
D. Hyponatremia
Correct Answer: C
Rationale: Phosphorus and calcium maintain an inverse relationship in the human body’s extracellular
fluid. When serum phosphorus levels are low, calcium levels typically rise as the body attempts to
maintain homeostasis. Hypocalcemia would usually be seen with high phosphorus levels, such as in
chronic kidney disease. Potassium and sodium levels are not directly tied to phosphorus through the
same regulatory mechanism as calcium. Monitoring both levels is essential for patients with renal issues
or nutritional deficiencies.
4. An older adult patient is admitted with dehydration. Which physiological change makes this population
more susceptible to fluid volume deficit?
A. Increased thirst mechanism
, B. Decreased lean muscle mass
C. Decreased glomerular filtration rate
D. Increased total body water
Correct Answer: B
Rationale: Older adults have a higher risk of dehydration due to a decrease in lean muscle mass and a
subsequent decrease in total body water. Muscle holds more water than fat, so losing muscle reduces the
body’s reservoir of fluids. Additionally, the thirst sensation often diminishes with age, making patients
less likely to drink voluntarily. Their kidneys also become less efficient at concentrating urine as the
glomerular filtration rate declines. These factors combined require nurses to be vigilant in monitoring
fluid intake and output in elderly patients.
5. A patient’s ABG results are: pH 7.31, PaCO2 52, HCO3 26. How should the nurse interpret these findings?
A. Metabolic Acidosis
B. Respiratory Acidosis
C. Respiratory Alkalosis
D. Metabolic Alkalosis
Correct Answer: B
Rationale: The pH of 7.31 indicates acidosis because it is below the normal range of 7.35 to 7.45. The
PaCO2 is elevated at 52, which is consistent with respiratory retention of carbon dioxide. Since the
bicarbonate (HCO3) is within the normal range of 22 to 26, the primary cause is respiratory. This
condition often occurs in patients with COPD or respiratory depression from sedation. The nurse should
focus on improving ventilation to blow off the excess carbon dioxide.
Updated and Latest Questions and Correct Answers with
Rationale
1. A patient presents with a serum potassium level of 6.2 mEq/L. Which medication should the nurse
anticipate administering first to stabilize the cardiac membrane?
A. Sodium Polystyrene Sulfonate (Kayexalate)
B. Regular Insulin and Dextrose 50%
C. Calcium Gluconate
D. Furosemide (Lasix)
Correct Answer: C
Rationale: Calcium gluconate is administered to stabilize the cardiac cell membrane and prevent life-
threatening arrhythmias in severe hyperkalemia. While insulin and dextrose help shift potassium into
cells, they do not stabilize the heart directly. Sodium polystyrene sulfonate is used for actual removal of
potassium but takes longer to act. Furosemide promotes potassium excretion through the kidneys but is
not the fastest emergency stabilization method. The nurse must prioritize cardiac protection before
focusing on lowering the total potassium level.
2. During the preoperative assessment, a patient reports a family history of high fever and muscle rigidity
during surgery. Which condition should the nurse suspect?
A. Anaphylactic reaction
B. Hypovolemic shock
C. Postoperative ileus
D. Malignant hyperthermia
,Correct Answer: D
Rationale: Malignant hyperthermia is a rare but life-threatening genetic disorder triggered by certain
volatile anesthetic gases and succinylcholine. The primary clinical signs include a rapid rise in body
temperature and severe muscle contractions or rigidity. A family history is a significant risk factor that
necessitates immediate communication with the surgical team. If triggered, the emergency treatment
involves the administration of dantrolene sodium to stop muscle metabolism. Preoperative identification
is critical for planning a safe anesthetic approach for the patient.
3. A nurse is caring for a patient with a phosphorus level of 1.8 mg/dL. Which electrolyte imbalance is most
commonly associated with this finding?
A. Hyperkalemia
B. Hypocalcemia
C. Hypercalcemia
D. Hyponatremia
Correct Answer: C
Rationale: Phosphorus and calcium maintain an inverse relationship in the human body’s extracellular
fluid. When serum phosphorus levels are low, calcium levels typically rise as the body attempts to
maintain homeostasis. Hypocalcemia would usually be seen with high phosphorus levels, such as in
chronic kidney disease. Potassium and sodium levels are not directly tied to phosphorus through the
same regulatory mechanism as calcium. Monitoring both levels is essential for patients with renal issues
or nutritional deficiencies.
4. An older adult patient is admitted with dehydration. Which physiological change makes this population
more susceptible to fluid volume deficit?
A. Increased thirst mechanism
, B. Decreased lean muscle mass
C. Decreased glomerular filtration rate
D. Increased total body water
Correct Answer: B
Rationale: Older adults have a higher risk of dehydration due to a decrease in lean muscle mass and a
subsequent decrease in total body water. Muscle holds more water than fat, so losing muscle reduces the
body’s reservoir of fluids. Additionally, the thirst sensation often diminishes with age, making patients
less likely to drink voluntarily. Their kidneys also become less efficient at concentrating urine as the
glomerular filtration rate declines. These factors combined require nurses to be vigilant in monitoring
fluid intake and output in elderly patients.
5. A patient’s ABG results are: pH 7.31, PaCO2 52, HCO3 26. How should the nurse interpret these findings?
A. Metabolic Acidosis
B. Respiratory Acidosis
C. Respiratory Alkalosis
D. Metabolic Alkalosis
Correct Answer: B
Rationale: The pH of 7.31 indicates acidosis because it is below the normal range of 7.35 to 7.45. The
PaCO2 is elevated at 52, which is consistent with respiratory retention of carbon dioxide. Since the
bicarbonate (HCO3) is within the normal range of 22 to 26, the primary cause is respiratory. This
condition often occurs in patients with COPD or respiratory depression from sedation. The nurse should
focus on improving ventilation to blow off the excess carbon dioxide.
