NCLEX Lab Values Nursing Students Need to Know

The NCLEX exam is the capstone of your journey to becoming a registered nurse, licensed practical nurse, or licensed vocational nurse. But knowing what to study, particularly NCLEX lab values can be difficult. Not only are lab values for the NCLEX presented in complex word problems, but there are seemingly endless values to learn.

As you study for the NCLEX, you should pay careful attention to the most routine lab values. In this article, we'll talk about common lab values for NCLEX questions and their ranges and give you tips on how to prepare for them.

Common NCLEX Lab Values and Ranges

It’s important to understand the normal range for the lab values and the reason why a medical provider would order them.  Here are the common normal lab values for the NCLEX you should know.

Complete Blood Count

A complete blood count (CBC) measures five key components, including:

• Red Blood Cell: Cells that carry oxygen
• White Blood Cell: Cells that fight infection
• Hemoglobin: Oxygen-carrying protein in red blood cells
• Hematocrit: Proportion of red blood cells to the fluid component, or plasma, in blood
• Platelets: Help with blood clotting

What is a CBC Used For?

A CBC can be used to identify infections, anemia, autoimmune disorders, bone marrow disorders, thrombocytopenia, erythrocytosis, and different types of cancer, including leukemia. 

When to Order a CBC

A healthcare provider may order a CBC if a patient has:

• Bruising
• Bleeding
• Fatigue
• Dizziness
• Weakness
• Inflammation
• Joint pain
• Blood pressure concerns
• Heart issues

Normal CBC Levels

• WBC: 4,500 to 11,000
• Hemoglobin: 11 to 18 g/dL
• Hematocrit: Women 36-44%, Men 41-50%
• Platelets: 150,000 to 450,000

Metabolic Panel

NCLEX lab values questions will also assess your knowledge of metabolic panel ranges. According to the National Library of Medicine, a metabolic panel is a  group of blood tests that provides information about your body's metabolism. There are two panels that  are commonly referred to as a metabolic panels:

• Basic Metabolic Panel (BMP)
• Complete Metabolic Panel (CMP)

BMP Normal Lab Values

Normal lab findings for a BMP are:

• BUN: 6 to 20 mg/dL
• CO2 (carbon dioxide): 23 to 29 mmol/L
• Creatinine: 0.8 to 1.2 mg/dL
• Glucose: 64 to 100 mg/dL
• Chloride: 96 to 106 mmol/L
• Potassium: 3.7 to 5.2 mEq/L
• Sodium: 136 to 144 mEq/L
• Calcium: 8.5 to 10.2 mg/dL

CMP Normal Lab Values

A CMP measures all of the above and the following:

• ALP: 44 to 147 (IU/L)
• AST: 8 to 33 U/L
• ALT: 4 to 36 U/L
• Bilirubin: 0.1 to 1.2 mg/dL
• Total Protein: 6.0 to 8.3 g/dL
• Albumin: 3.4 to 5.4 g/dL
• Globulin: 2.0 to 3.5 g/dL

What is a Metabolic Panel Used For?

This is a very common blood test that is run for a variety of reasons, but generally - most hospitalized patients will have this test ordered. This lab can be used to check for medical conditions such as diabetes, high blood pressure, and kidney disease. 

Arterial Blood Gas

An arterial blood gases (ABG) test is a blood test that measures the acidity, or pH, and the levels of oxygen (O2) and carbon dioxide (CO2) from an artery. 

The test is used to check the function of the patient’s lungs and how well they are able to move oxygen into the blood and remove carbon dioxide.  

ABG Components

There are six key components to an ABG. They include:

1. pH: Measures the balance of acids and bases in your blood
2. Partial pressure of oxygen (PaO2): Measures the pressure of oxygen dissolved in your blood
3. Partial pressure of carbon dioxide (PaCO2): Measures the amount of carbon dioxide in your blood and how well carbon dioxide can move out of your body
4. Bicarbonate (HCO3): Calculated using the measured values of pH and PaCO2 to determine the amount of the basic compound made from carbon dioxide (CO2)
5. Oxygen saturation (O2 Sat): Measures how much hemoglobin in your blood is carrying oxygen
6. Oxygen content (O2CT): Measures the amount of oxygen in your blood
7. Hemoglobin: Measures the amount of hemoglobin in your blood

ABG Normal Values

The aforementioned components all have different normal values and represent different aspects of blood gas. According to the National Institute of Health, typical normal values are:

• pH: 7.35-7.45
• Partial pressure of oxygen (PaO2): 75 to 100 mmHg
• Partial pressure of carbon dioxide (PaCO2): 35-45 mmHg
• Bicarbonate (HCO3): 22-26 mEq/L
• Oxygen saturation (O2 Sat): 94-100%

When to Order an ABG

A medical provider may order an ABG for a variety of reasons, including but not limited to, lung failure, sepsis, pneumonia, hypovolemic shock, trauma, asthma, drug overdose, heart failure, and emphysema.

Coagulation Level

Coagulation levels refer to several labs, including:

• Activated partial thromboplastin time (PTT)
• Prothrombin time (PT)
• Thrombin time (TT)
• Fibrinogen
• INR

When to Run Coagulation Levels

Some common reasons a medical provider may run coagulation levels is concern for liver disease, vitamin K deficiency, if a patient is on blood-thinning medication, and heart disease/problem. Labs may be ordered if a patient is suffering from the following symptoms:

• Bleeding
• Easy bruising
• Swelling
• Pain
• Stiffness
• Blood clots

Normal Coagulation Levels

Normal levels for coagulation tests include:

• PTT: 25 to 35 seconds
• PT: 11 to 13.5 seconds
• TT: 14 to 19 seconds
• Fibrinogen: 200 to 400 mg/dL
• INR: 1.1 or below 

Lipid Panel

A lipid panel is also called a cholesterol panel, fasting lipid panel, or non-fasting lipid panel. They include:

• Total Cholesterol: Overall cholesterol level — the combination of LDL, VLDL, and HDL
• Low-density lipoprotein (LDL): Referred to as “bad cholesterol,” LDL collects in blood vessels and is the main source of cholesterol buildup and blockage in the arteries
• Very low-density (VLDL) lipoprotein: Total cholesterol minus your HDL
• High-density (HDL) lipoprotein: Referred to as “good cholesterol,” HDL helps decrease the buildup of LDL in your blood vessels
• Triglycerides (TG): Type of fat in the blood

Normal Lipid Panel Values

According to Johns Hopkins Medicine, typical normal values are:

• Total cholesterol: Less than 200 mg/dL
• LDL: Less than 100 mg/dL
• VLDL: Between 2 and 30 mg/dL
• HDL: 45 to 70 mg/dL for men, 50 to 90 mg/dL for women
• Triglycerides: Less than 150 mg/dL

Hemoglobin A1C

An A1C level measures average blood sugar levels over the past 3 months. The A1C test is also called the glycated hemoglobin, glycosylated hemoglobin, hemoglobin A1C or HbA1c test. 

When to Order an A1C Test

This lab test is used to help diagnose prediabetes and diabetes as well as manage patients already diagnosed with diabetes. 

A1C Values 

• Normal: Below 5.7%
• Prediabetes: 5.7% to 6.4%
• Diabetes: 6.5% or more

Drug Levels

NCLEX lab values questions incorporate drug levels because they're common and vital. Since some medications have therapeutic blood levels, these values help medical providers safely titrate medication doses so that patients receive the proper amount of their medication. 

When to Order Drug Levels

Healthcare providers will routinely order drug levels until a safe level is obtained. 

Normal Drug Level Lab Values

The most common drug levels are:

• Digoxin: 0.5-2 ng/mL
• Carbamazepine: 4-10 mcg/mL
• Dilantin: 10-20 mcg/mL
• Theophylline: 10-20 mcg/mL
• Phenobarbital: 15-40 mcg/mL
• Lithium: 0.5-1.2 mmol/L
• Valproic Acid: 50-100 mcg/mL

NCLEX Lab Values: Common Question Formats and Variations

Lab values for NCLEX questions are never straightforward. You won't come across an exam question asking you to pick the normal or abnormal lab value range. Instead, the question may focus on problems, signs, and/or symptoms a patient may be experiencing. 

NCLEX LAB VALUES Example Question 1

For example, a question might indicate a patient is suffering from the following signs and symptoms:

• Fruity-smelling breath
• Nausea and vomiting
• Shortness of breath
• Dry mouth
• Weakness
• Confusion
• Abdominal pain

These are all signs of hyperglycemia or TOO HIGH blood sugar levels. The question might ask you to indicate which commonly ordered blood test should be drawn. In turn, you must know that the patient needs their glucose level checked, and glucose is part of a Metabolic Panel.

NCLEX LAB VALUES Example Question 2

Another example of a question that would be asked on the NCLEX regarding lab values is about a patient with an elevated WBC. A question may indicate that the patient’s WBC is 350,000, and the patient is also experiencing sudden, unintentional weight loss, bruising, recurrent nosebleeds, and swollen lymph nodes.

First, you will have to determine if the WBC is elevated or below the normal range. A normal range for a WBC is 4,500 to 11,000. Knowing the normal range will indicate that the WBC of 350,000 is extremely elevated, and coupled with the signs and symptoms, this patient may be diagnosed with leukemia.

Lab Values for the NCLEX: Why They Are Important

All labs for nurses are important, but the labs included above are the most commonly ordered labs. 

While it is important to understand and know these NCLEX lab values to pass the test, it is also extremely important to know these labs for your future nursing career. 

Understanding these labs' normal and abnormal ranges is essential to providing the best care possible for your patients. 

The Best Way to Prepare for NCLEX Lab Values Questions

There are several key ways to prepare for questions involving lab values for the NCLEX.

1. Establish an NCLEX study routine
2. Dedicate at least 8-10 weeks for NCLEX study before your exam date
3. Plan strategic study breaks to avoid burnout
4. Incorporate NCLEX lab value questions into your normal study routine
5. Use online or in-person NCLEX review course
6. Practice with a study group to solidify your knowledge
7. Take practice exams
8. Avoid getting caught off guard by learning how the NCLEX works and your time limit

NCLEX Success at Your Fingertips

Earning your nursing degree is just one step toward becoming a practicing nurse. Passing the NCLEX-RN or NCLEX-PN will provide you with the certifications necessary to begin your nursing career.  But NCLEX lab values are just one part of the exam.

If you want to learn more about how to pass your NCLEX, check out these tips from real nurses.

*This website is provided for educational and informational purposes only and does not constitute providing medical advice or professional services. The information provided should not be used for diagnosing or treating a health problem or disease.