🧪 NCLEX Lab Values

Must-know lab values for the exam!

ELI5: Why Lab Values Matter

Lab values are like a window into what's happening inside the body. As a nurse, you'll be checking these values to see if patients are healthy or if something's wrong!

TL;DR: Know the normal ranges for common labs - you'll see these on the NCLEX!

🩸 Complete Blood Count (CBC)

Test	Normal Range	What It Means
WBC	5,000-10,000	White blood cells - infection fighting
RBC	4.5-5.5 million	Red blood cells - oxygen carrying
Hgb	12-16 g/dL	Hemoglobin - oxygen protein
Hct	36-50%	Hematocrit - blood cell percentage
Platelets	150,000-400,000	Blood clotting

🧪 Metabolic Panel (BMP/CMP)

Test	Normal Range	What It Means
Glucose	70-100 mg/dL	Blood sugar
BUN	10-20 mg/dL	Kidney function
Creatinine	0.6-1.2 mg/dL	Kidney function
Sodium	135-145 mEq/L	Electrolyte
Potassium	3.5-5.0 mEq/L	Electrolyte - critical!
Chloride	95-105 mEq/L	Electrolyte
CO2	23-30 mEq/L	Kidney/lung function
Calcium	9-11 mg/dL	Bones & nerves

❤️ Cardiac Markers

Test	Normal Range	What It Means
Troponin I	< 0.04 ng/mL	Heart damage - MI indicator
BNP	< 100 pg/mL	Heart failure indicator
CK-MB	0-25 U/L	Heart muscle damage

🫁 ABG (Arterial Blood Gas)

Test	Normal Range	What It Means
pH	7.35-7.45	Acid-base balance
PaO2	80-100 mmHg	Oxygen level
PaCO2	35-45 mmHg	Carbon dioxide
HCO3	22-26 mEq/L	Bicarbonate
O2 Sat	95-100%	Oxygen saturation

💊 Therapeutic Drug Levels

Drug	Therapeutic Range
Lithium	0.6-1.2 mEq/L
Digoxin	0.5-2.0 ng/mL
Dilantin	10-20 mcg/mL
Aminophylline	10-20 mcg/mL
Vancomycin	5-15 mcg/mL

⚠️ Critical Values - Call Provider IMMEDIATELY!

Potassium: < 2.5 or > 6.5 mEq/L
Sodium: < 120 or > 155 mEq/L
Glucose: < 50 or > 400 mg/dL
WBC: > 30,000 or < 2,000
Platelets: < 20,000
troponin: Any elevated level
ABG pH: < 7.2 or > 7.6

💡 NCLEX Tips

Know potassium, sodium, and glucose ranges - most tested!
Understand what HIGH or LOW values mean for the patient
Critical values = immediate action needed
Look at trends - one value alone may not tell the whole story

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Disclaimer: This content is for educational purposes only.