Question 1

A client received a kidney transplant 2 months ago. He’s admitted to the hospital with the diagnosis of acute rejection. Which of the following assessment findings would be expected?

Accepted Answer

Answer reason: A falling GFR leads to retention of nitrogenous wastes, so BUN and serum creatinine rise and are key early indicators of graft dysfunction. Normal temperature is not expected because rejection often produces systemic inflammatory findings (e.g., fever, graft tenderness) even if subtle in immunosuppressed patients. Hypotension is not a typical hallmark of rejection (more consistent with volume depletion/shock), and a decreased WBC count suggests medication-related marrow suppression rather than an active rejection process.

Question 2

A client’s ABG analysis reveals a pH of 7.18, PaCO2 of 72 mm Hg, PaO2 of 77 mm Hg, and HCO3- of 24 mEq/L. What do these values indicate?

Accepted Answer

Answer reason: The bicarbonate is normal (24 mEq/L), supporting an acute/uncompensated process rather than a chronic state with renal compensation. The mildly low PaO2 further supports hypoventilation as a likely physiologic problem accompanying CO2 retention. In contrast, a primary metabolic acidosis would present with a low HCO3- and a compensatory low PaCO2, which is not seen here.

Question 3

Case Event: The nurse is reviewing the laboratory results of a client who is receiving magnesium sulfate by IV infusion and notes that the magnesium level is 3.5 mg/dL (1.44 mmol/L), Question Query: Based on this laboratory result, the nurse would most likely expect to note which finding in the client?

Accepted Answer

Answer reason: A serum magnesium level of 3.5 mg/dL is above the normal reference range but remains below the typical therapeutic and toxic levels associated with magnesium sulfate therapy. At this level, the client is unlikely to exhibit significant clinical manifestations. Signs such as tremors and hyperactive reflexes are associated with hypomagnesemia, while respiratory depression occurs at much higher magnesium levels. Therefore, no specific clinical findings are expected at this stage, although continued monitoring is required for rising levels and early signs of toxicity.

Question 4

The nurse should assess for Trousseau’s sign in a client after noting which electrolyte abnormality?

Accepted Answer

Answer reason: Trousseau’s sign reflects neuromuscular irritability due to hypocalcemia, which lowers the threshold for nerve and muscle depolarization. A calcium of 7.7 is below the typical adult reference range and can precipitate latent tetany, making carpopedal spasm with blood pressure cuff inflation more likely. In contrast, mild hyponatremia or hypochloremia does not classically cause this specific tetany sign, and hypokalemia more commonly presents with weakness, cramps, and dysrhythmias. Therefore, the abnormal value that should trigger assessment for this sign is the low calcium level.

Question 5

A patient who has received chemotherapy for cancer treatment is given an injection of Epoetin. Which of the following should reflect the findings in a complete blood count (CBC) drawn several days later?

Accepted Answer

Answer reason: Several days after initiation, reticulocytosis occurs followed by measurable increases in hematocrit as erythropoiesis continues. It does not stimulate neutrophil production (that would be more consistent with G-CSF agents such as filgrastim), and it is not intended to raise platelets. Serum iron typically does not increase; iron stores may actually be consumed during increased erythropoiesis, so iron supplementation may be needed.

Question 6

Matteo is diagnosed with dehydration and underwent a series of tests. Which laboratory result would warrant immediate intervention by the nurse?

Accepted Answer

Answer reason: Electrolyte abnormalities that can trigger dysrhythmias require prompt nursing action. A potassium of 3.1 mEq/L indicates hypokalemia, which can cause muscle weakness, ileus, and dangerous cardiac conduction changes (e.g., ventricular ectopy, U waves), especially in a dehydrated patient who may also have ongoing GI or renal losses. This result warrants immediate assessment (cardiac status, ECG if ordered), provider notification, and anticipated potassium replacement with safety precautions. By contrast, the sodium 138 mEq/L is within normal limits, and the glucose 120 mg/dL and creatinine 0.6 mg/100 mL are not typically urgent in this context.

Question 7

Which diagnostic test would be used first to evaluate a client with upper GI bleeding?

Accepted Answer

Answer reason: These labs provide an immediate baseline for anemia and guide urgency of resuscitation, transfusion thresholds, and monitoring trends over time. Definitive localization tests like endoscopy are important but should follow stabilization and basic assessment, and an upper GI series is not appropriate in active bleeding because it can delay care and interfere with subsequent endoscopy. MRI has no role as a first-line test in acute GI hemorrhage evaluation.

Question 8

The client who has menorrhagia complains to the nurse of feeling listless and tired all the time. Which laboratory data should the nurse monitor?

Accepted Answer

Answer reason: Heavy menstrual bleeding can cause chronic blood loss leading to iron-deficiency anemia, which commonly presents with fatigue, weakness, and listlessness. Monitoring hemoglobin and hematocrit directly assesses the severity of anemia and trends response to treatment (e.g., iron therapy, hormonal management, or transfusion decisions if severe). BUN evaluates renal function and does not explain symptoms driven by blood loss. WBC count is more relevant to infection/inflammation, and urinalysis does not quantify oxygen-carrying capacity or blood loss impact.

Question 9

The nurse is assessing a patient after returning from surgery. After reviewing the patient's lab results, the nurse should notify the physician of?

Accepted Answer

Answer reason: Potassium 3.1 mEq/L. Postoperative patients are at heightened risk for dysrhythmias, and clinically significant hypokalemia warrants prompt provider notification and replacement planning. A value of 3.1 mEq/L is below the typical safe range and can contribute to weakness, ileus, and ECG changes, especially with fluid shifts, diuretics, or NG suction. In contrast, sodium 144 mEq/L is within normal limits, and a phosphorus of 3.8 is generally normal. While magnesium 1.4 is low and may also need repletion, hypokalemia at this level is a more immediate arrhythmia trigger and often requires coordinated correction (frequently alongside magnesium).

Question 10

The nurse is caring for a client who is taking digoxin and is complaining of nausea. The nurse gathers additional assessment data and checks the most recent laboratory results. Which laboratory value requires the need for follow-up by the nurse?

Accepted Answer

Answer reason: Potassium 3.3 mEq/L (3.3 mmol/L) Hypokalemia increases myocardial sensitivity to digoxin because fewer potassium ions compete at the Na+/K+ ATPase, raising the risk of digoxin toxicity. Nausea is an early, common manifestation of digoxin toxicity, so an accompanying low potassium level is a clinically significant red flag that warrants prompt nursing follow-up and provider notification. A sodium of 138 mEq/L is normal and does not explain toxicity risk. The magnesium and phosphorus values shown are within typical reference ranges and are less immediately concerning than hypokalemia in a patient on digoxin.

Question 11

Mr. Smith lab values include a serum potassium of 2.8 mg/dL (2.8 mmol/L). What is the priority nursing action at this time?

Accepted Answer

Answer reason: Severe hypokalemia (K+ 2.8 mmol/L) places the patient at high risk for life-threatening dysrhythmias and requires prompt medical management and monitoring. The nurse’s priority is to rapidly escalate this critical abnormal lab to the provider so orders can be obtained (e.g., potassium replacement route/dose, ECG monitoring, and evaluation of cause). Teaching about diet is appropriate only after stabilization and will not correct an acute, potentially dangerous deficit. Oxygen or a low-rate maintenance saline infusion does not address the immediate cardiac risk created by the low potassium.

Question 12

After performing a urine point of care (POC) test on a patient’s urine sample, the patient’s urine specific gravity (SG) is 1.030. This is indication of?

Accepted Answer

Answer reason: Urine specific gravity reflects urine concentration relative to plasma, rising when the kidneys conserve water. An SG of 1.030 is at the high end of normal and is commonly interpreted as concentrated urine, most consistent with volume depletion. Acidic vs alkaline urine is determined by urine pH, not specific gravity, so those options do not follow from the given value. A well-hydrated patient would be expected to have a more dilute SG closer to ~1.005–1.015.

Question 13

A nurse is entering the most recent laboratory report of a client on the telemetry floor. The client is currently asymptomatic, and the telemetry monitor indicates sinus rhythm. Which of the following critical values is most likely due to laboratory error?

Accepted Answer

Answer reason: Potassium of 7.0 mEq/L Severe hyperkalemia is expected to cause cardiac conduction abnormalities (e.g., peaked T waves, PR prolongation, QRS widening, bradyarrhythmias) and can rapidly become life-threatening. An asymptomatic client with a stable sinus rhythm on telemetry makes a true value of 7.0 mEq/L less plausible than specimen-related pseudohyperkalemia (most commonly hemolysis during draw/handling). In contrast, markedly elevated BUN and creatinine can occur in chronic kidney disease and may be present without acute symptoms or immediate rhythm changes. Mild-moderate hypernatremia (155 mEq/L) can also be relatively asymptomatic early and does not specifically contradict sinus rhythm.

Question 14

Following several episodes of vomiting with an increasing temperature in a 2-year-old child, the nurse plans to monitor the client for dehydration. Which of the following findings indicates the child is dehydrated?

Accepted Answer

Answer reason: Specific gravity of 1.034 Dehydration causes the kidneys to conserve water, producing concentrated urine with an elevated urine specific gravity. A value of 1.034 is above the typical pediatric range and is a direct, objective indicator of fluid volume deficit. Irritability can occur with dehydration but is nonspecific and can be caused by fever or discomfort. The listed blood pressure may be within normal limits for a 2-year-old, and a depressed fontanel is more reliable in younger infants and can be difficult to assess at age 2.

Question 15

A patient is experiencing frequent runs of ventricular tachycardia. The nurse should obtain an order from the provider to check serum levels of?

Accepted Answer

Answer reason: Low potassium and low magnesium are classic, high-yield reversible contributors to ventricular dysrhythmias and can also predispose to torsades-like rhythms. Repleting magnesium is often necessary to effectively correct hypokalemia and stabilize cardiac conduction. Calcium and sodium abnormalities are less directly linked as primary, routine triggers for recurrent VT compared with potassium and magnesium in standard clinical evaluation.

Question 16

A nurse cares for a client who is prescribed ticlopidine. Which laboratory value indicates to the nurse that the client is experiencing an adverse reaction?

Accepted Answer

Answer reason: An absolute neutrophil count around 500 cells/mm3 represents severe neutropenia and is a classic lab signal of this adverse reaction requiring prompt provider notification and likely discontinuation. The other values shown may be abnormal (hyperglycemia, mild hypokalemia) or within expected range (hemoglobin 12.1 g/dL) but are not characteristic hallmark toxicities of this drug. This lab finding is therefore the most directly drug-related and safety-critical abnormality.

Question 17

A diabetic female has the following lab results: fasting glucose of 218 mg/dl, creatinine of 0.8 mg/dl, potassium of 4.1 mEq/l, hemoglobin of 8 mg/dl, CO2 of 41 mEq/l. Which result is critical and should be reported to the physician immediately?

Accepted Answer

Answer reason: A hemoglobin of 8 g/dL indicates significant anemia with reduced oxygen-carrying capacity and potential for symptomatic tissue hypoxia, especially if there is ongoing blood loss or cardiovascular comorbidity. The other values are not immediately critical here: creatinine 0.8 mg/dL and potassium 4.1 mEq/L are normal, and fasting glucose 218 mg/dL is elevated but typically not an emergency in isolation. A CO2 (bicarbonate) of 41 mEq/L is high and suggests metabolic alkalosis/compensation but is generally less immediately dangerous than marked anemia unless accompanied by severe symptoms or deranged pH.

Question 18

The nurse admits a client in the ED and performs an arterial blood gas. The results are pH: 7.51, PCO2: 49, PO2: 85, and HCO3: 35. Which of the following describes this ABG result?

Accepted Answer

Answer reason: The elevated PCO2 (49) represents hypoventilatory respiratory compensation attempting to retain CO2 and lower the pH toward normal. Because the pH remains outside the normal range despite compensation, the disorder is only partial compensation rather than full compensation. The other choices conflict with the direction of the pH (acidosis) or ignore the clear compensatory rise in PCO2.

Question 19

A nurse cares for a client who undergoes a thoracentesis, which reveals leukocytosis. How does the nurse interpret these results?

Accepted Answer

Answer reason: Leukocytosis indicates an elevated white blood cell count, which most commonly reflects an inflammatory response to infection. In the context of thoracentesis/pleural fluid evaluation, increased WBCs support an infectious process such as parapneumonic effusion or empyema. Bleeding would more directly suggest increased red blood cells/hematocrit in the sample and clinical signs of hemorrhage rather than isolated leukocytosis. Heart failure typically causes a transudative effusion and is not characterized by leukocytosis as the primary finding.

Question 20

A nurse cares for a client with a GI bleed. The client is short of breath, exhibits clear lung sounds, and has an oxygen saturation of 98%. The nurse evaluates which laboratory results?

Accepted Answer

Answer reason: With a GI bleed, blood loss reduces hemoglobin, decreasing arterial oxygen content even if SpO2 remains normal because saturation only reflects the percentage of hemoglobin bound with oxygen. Evaluating hemoglobin and hematocrit directly assesses the degree of anemia/ongoing blood loss and guides urgency of transfusion or further interventions. ABGs primarily assess ventilation and oxygenation and would be less diagnostic here given the normal SpO2 and clear breath sounds.

Question 21

The RN is reviewing the client's morning laboratory results. Which of these results is of most concern?

Accepted Answer

Answer reason: Serum magnesium level of 0.8 mEq/L (0.4 mmol/L) Magnesium is critical for cardiac electrical stability and neuromuscular function, and clinically significant hypomagnesemia increases risk for dangerous dysrhythmias (including torsades de pointes) and seizures. A value of 0.8 mEq/L is clearly below typical reference ranges, making it the most urgent abnormality to address. By contrast, potassium 5.2 mEq/L is only mildly elevated and is often monitored rather than emergently treated unless higher or accompanied by ECG changes. Sodium 134 mEq/L and calcium 10.6 mg/dL are borderline deviations and generally pose less immediate threat than severe magnesium depletion.

Question 22

The nurse has been floated to the telemetry unit for the day. The monitor technician informs the nurse that the client has developed prominent U waves. Which laboratory value should be checked immediately?

Accepted Answer

Answer reason: The most immediate priority is to verify the serum potassium level to confirm the suspected electrolyte abnormality and guide urgent replacement if needed. While magnesium deficiency can contribute to arrhythmias, U waves point more specifically to low potassium as the primary abnormality. Prompt identification and correction helps prevent progression to torsades de pointes or ventricular tachycardia, especially if the patient is on diuretics or has GI losses.

Question 23

The nurse has made the following client observations. It would require follow-up if a client who receives prescribed?

Accepted Answer

Answer reason: An HbA1c of 11% reflects markedly poor long-term glycemic control and high risk for hyperglycemia-related complications, so it warrants prompt follow-up for medication regimen change and adherence/education assessment. In contrast, a pulse of 60 with metoprolol can be acceptable if asymptomatic and within ordered parameters, and flushing with niacin is a common expected effect. Easy bruising can occur with corticosteroid use due to skin/vascular fragility, but the most urgent actionable abnormality here is the severely elevated HbA1c indicating treatment failure.

Question 24

A client brought to the emergency department states that he has accidentally been taking 2 times his prescribed dose of warfarin for the past week. After noting that the client has no evidence of obvious bleeding, the nurse plans to take which action?

Accepted Answer

Answer reason: Warfarin’s anticoagulant effect is monitored with PT/INR, so the immediate priority in an asymptomatic overdose is to quantify the degree of anticoagulation and bleeding risk. A week of double dosing can significantly elevate INR even before visible bleeding occurs, and management is guided by the INR value and any evidence of bleeding. aPTT is used to monitor unfractionated heparin rather than warfarin, so it would not appropriately assess this medication error. Antidote therapy (vitamin K) or transfusion/blood products are generally reserved for elevated INR with significant bleeding or very high INR, not as the first step when no bleeding is present.

Question 25

A client is admitted with a suspected myocardial infarction (MI). What laboratory test is most specific for confirming an MI?

Accepted Answer

Answer reason: They rise within hours of infarction and remain elevated for days, improving diagnostic sensitivity beyond early presentation. CK-MB is less specific because it can increase with skeletal muscle injury and is therefore more prone to false positives. CRP is a nonspecific inflammation marker, and BNP reflects ventricular stretch/heart failure rather than acute myocardial necrosis.

Question 26

The nurse is gathering data on a 5-week-old admitted with a suspected diagnosis of pyloric stenosis. The nurse should expect to find which laboratory value?

Accepted Answer

Answer reason: Hematocrit of 57% (0.57) [22%] Pyloric stenosis causes persistent projectile vomiting with loss of fluid and electrolytes, leading to dehydration and hemoconcentration. Hemoconcentration raises the hematocrit, so an elevated value is expected on admission before adequate rehydration. A very low blood pH would suggest severe acidosis, whereas pyloric stenosis classically produces a metabolic alkalosis from loss of gastric acid. Hyperkalemia is not typical early because vomiting and volume depletion tend to lower potassium, and marked leukocytosis is not a classic primary finding of this condition.

Question 27

The nurse is reviewing the arterial blood gas (ABG) results of a client in the respiratory care unit and notes a pH of 7.38; Pco2, 38 mm Hg; Po2, 86 mm Hg; and HCO3, 23 mEq/L. The nurse should interpret that the client's blood gases indicate which finding?

Accepted Answer

Answer reason: The pH 7.38 is within normal (7.35–7.45), PaCO2 38 is within normal (35–45), and HCO3 23 is within normal (22–26), so there is no primary respiratory or metabolic disturbance. PaO2 86 is also within the expected adult range (~80–100), supporting adequate oxygenation. A common trap is to label a “borderline” pH as acidosis/alkalosis, but without an out-of-range pH or a compensatory shift in PaCO2/HCO3, the correct interpretation is normal ABGs.

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Abnormal Laboratory Values Practice Test 6

Abnormal Laboratory Values NCLEX Practice Test

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