NCLEX® 101: Lab Values: 50 Practice Questions with Answers and Rationales...The RAPID and EASY Method to ACE the NCLEX RN Review

One of the most confusing parts of learning lab values is knowing which ones you need to study. The NCLEX® does not publish an official list; but we have compiled a list of values that are known to appear most often.
Memorize these core lab values and then drill it down with the 50 practice questions.

In this guide we provide a brief overview of the most essential lab values you "NEED TO KNOW" followed by 50 practice questions and answers with detailed rationales.

These practice questions are designed to resemble true NCLEX-RN® test questions. The vast majority of test questions will be practical rather than theoretical. For most questions, you will be provided a clinical scenario and asked to make a decision based on the given situation.

Example Questions with Answer and Rationale

Question #12
The nurse educator is providing discharge teaching to a patient with newly diagnosed diabetes mellitus, type II. The client will leave with a prescription for insulin.

Which statement by the patient indicates a need for further education?
A. “I will reduce the amount of sugar in my diet and replace it with healthy alternatives”
B. “I will avoid foods that are high on the glycemic index.”
C. “If my blood glucose is less than 60 and I am feeling dizzy I will take a sugar supplement”
D. “My goal will be to get my glycosylated hemoglobin (Hgb A1c) above 12% by my next checkup”
 
Answer to #12
D. “My goal will be to get my glycosylated hemoglobin (Hgb A1c) above 12% by my next checkup”

Rationale:
Glycosylated hemoglobin (Hgb A1c) is a test that shows what blood glucose levels were on average over the past 3 months. In a healthy non-diabetic patient this number should be between 4-6%. The goal for an adult with diabetes is less than 8%. An Hgb A1c of 12% indicates that the patient’s average blood glucose level was around 300 the past 3 months, this suggest poor control of blood sugar levels.

Question #17
Your patient has been diagnosed with diabetes insipidus. Which laboratory result supports this diagnosis?
A. Urine osmolality of 400 mOsm/kg
B. Serum sodium of 120 mEq/L
C. Serum osmolality of 280 mOsm/kg
D. Urinary specific gravity of 1.002
 
Answer to #17

D. Urinary specific gravity of 1.002

Rationale:
Urine specific gravity of 1.005 or less is hallmark of diabetes insipidus. However other conditions such as primary polydipsia and pyelonephritis as well as recent diuretic use could also result in low urine specific gravity.
Urine osmolality would be less than 300 and Serum sodium would be expected to be high not low in a patient with diabetes insipidus.