Lab Values for NCLEX RN

Complete Blood Count:

Red Blood Cells:	4.7 – 6.1 million cells per microlitre
White Blood Cells:	5 – 10 x 10^9/Litres
Hemoglobin:	< 100 is abnormal > 110 is abnormal
Hematocrit:	0.39 – 0.5%
Platelets:	150 – 400 x 10^9

WBC is important as it identifies the severity of infection. It is important to note that low WBC indicates immunocompromise and severely elevated WBC may require immediate attention.

HgB tells you the oxygen carrying capacity, low levels may require transfusions, elevated ones are also not normal and may require attention. NCLEX loves testing you on this.

HcT is the percentage of RBC in vessels so you need to know low levels of hematocrit may indicate low hemoglobin which leads to an increase in respiratory rate, heart rate, and shortness of breath.

Platelets are the actual amount in blood vessels. It is important because certain conditions require you to have less, but not too low and to be within the normal therapeutic range otherwise it indicates a bleeding risk. As a result it is important to remember the normal value of the total amount of platelets, the aPTT, PT and the therapeutic ranges for patient on certain medications. It is also important to remember why it is indicated for patients to be on blood thinners.

Coagulation Studies:

Activated partial thromboplastin time (aPTT):	25 – 30 secs
Heparin therapy for aPTT:	1.5 – 2 times normal value
Prothrombin Time (PT):	11 – 12.5 sec
Warfarin therapy and PT:	1.5 – 2.5 times normal value
International Normalised Ratio (INR):	Less than 1.0
Warfarin therapy and INR:	2.0 – 3.0

CBC “with differential”:

Neutrophil:	2 – 8 * 10^9 L
Eosinophil:	< 0.5 * 10^9 L

Although a differential also includes: Lymphocytes, monocytes, basophils it is very rarely tested on in the NCLEX so I have not chosen to study them.

Neutrophils and eosinophils are the most important for you to remember. Decreased neutrophils mean they are at risk of being infection, it is CRUCIAL to put them into an isolation room.

Eosinophils elevated may indicate exposure to allergen.

Lipid profile:

Total cholesterol:	<200 mg
HDL:	35 – 65 mg/dL
LDL:	<130 mg/dL
Triglycerides:	<130 mg/dL

Lipid profile is also tested on in the NCLEX. It is important to know that a higher level of HDL’s is optimal and lower levels of LDL’s and Triglycerides is optimal. You should know that if someone has high cholesterol it is medically indicated for them to take statin drugs which lower it.

Electrolyte profile:

Na:	135 – 145 mEq/L
K:	3.5 – 5.0 mEq/L
Ca:	9 – 10.5 mg/dL
Mg:	1.5 – 2.5 mg/dL
Mg Therapy:	4 – 7 mg/dL
Phosphate:	3.5 – 4.5 mg/dL

You must remember these. It comes a lot in different situations and you need to be able to identify if a patient has a condition or is taking a medication which one of these is going to be abnormal.

Liver:

AST	5 – 40 unit/L
ALT	8 – 20 unit/L
ALP	42 – 128 unit/L
Albumin	3.5 – 5.0 g/L
Ammonia	15 – 110 mg/dL

Liver enzymes as well as albumin and ammonia are important to remember as one of them could indicate damage to live tissue. Conditions such as ascites, liver cirrhosis and hepatic encephalopathy will cause abnormal lab values. As you will read in the conditions section, there are different situation which cause elevated liver values.

Kidneys:

Blood Urea Nitrogen	6 – 20 mg/dL
Serum Creatinine	0.6 – 1.2 mg/dL
Creatinine Clearance	~53 – 115 mL/min
Glomerular Filtration Rate	125 mL/min

Damage to kidneys is very high yield. Lab values are a must to remember. They will give you a condition and ask you to identify a lab value that is most concerning with a patient who has a certain condition.

Sugars:

Fasting Blood Glucose	< 110mg/dL
HbA1c	<5% = non diabetic 5.7 – 6.4% = prediabetic >6.5% = diabetic

Self-explanatory, you need to know these values in order to be able to identify if someone is pre-diabetic, diabetic etc…

Thyroid:

T3	70 – 205 ng/dL
T4	4 – 12 mcg/dL
Thyroid Stimulating Hormone	0.4 – 6 microunits/mL

NCLEX loves to ask questions on hypo and hyperthyroidism. Metabolism questions are very high yield and therefore it is important not to remember the range necessarily but to identify whether someone is going to have hypothyroidism or hyperthyroidism based on these values.

Other:

Urine specific gravity:	1.003 – 1.030
Normal Mean Arterial Pressure	70 – 105 mmHg
Creatine kinase	>250 Units/Litre
Calculate Mean Arterial Pressure:	Systolic BP + (Diastolic BP x 2)/3
Central venous pressure	2 – 8 mmHg
Pulmonary arterial wedge pressure PAWP	6 – 12 mmHg
Carboxyhemoglobin	<5% in non-smokers <10% in smokers
Chest tube blood loss	>100mL = contact Healthcare provider >5 – 10 mL/Kg/hour

<1.003 of urine specific gravity indicates light urine or excessive urine output. Common in diabetes insipidus exacerbations

>1.030 of urine specific gravity indicates concentrated urine or dehydration. Common in SIADH (symptom of inappropriate antidiuretic hormone).

Central venous pressure = indicates cardiac function

Jugular venous distention = pressure inside the vena cava

Pulmonary arterial wedge pressure = indicates left ventricular preload and left sided heart function

Carboxyhemoglobin = indicator of carbon monoxide poisoning

Arterial Blood Gases:

pH:	7.35 – 7.45
PaCO2:	35 – 45 mmHg
PaO2:	80 – 100 mmHg
HCO3	22 – 26 mEq/L
SaO2	>95%

This is an important concept for you to know. Identify what the arterial blood gas is showing.

You want to make sure you memorize these values and are able to interpret a client’s arterial blood gases and analyze them to identify what is wrong with the client.

• In the sections below, I will show you how I analyze someone’s ABG’s.
• You need to know how to do it for the NCLEX.

Drugs Therapy:

Digoxin	0.5 – 2.0 ng/mL
Lithium	0.6 – 1.2 mmol/L