[Infographic: Complete NCLEX Lab Values Reference Card — Printable]
Electrolytes
| Lab Value | Normal Range | Critical Low | Critical High |
|---|---|---|---|
| Sodium (Na+) | 135–145 mEq/L | <120 | >160 |
| Potassium (K+) | 3.5–5.0 mEq/L | <3.0 | >6.0 |
| Calcium (Ca++) | 8.5–10.5 mg/dL | <7.0 | >12.0 |
| Magnesium (Mg++) | 1.5–2.5 mEq/L | <1.0 | >4.0 |
| Phosphorus | 2.5–4.5 mg/dL | <1.0 | >8.0 |
| Chloride (Cl-) | 98–106 mEq/L | <80 | >115 |
Haematology
| Lab Value | Female Normal | Male Normal | Critical |
|---|---|---|---|
| Haemoglobin (Hgb) | 12–16 g/dL | 14–18 g/dL | <7 or >20 |
| Haematocrit (Hct) | 36–46% | 42–52% | <21% or >60% |
| WBC | 4,500–11,000 cells/mcL | <2,000 or >30,000 | |
| Platelets | 150,000–400,000/mcL | <50,000 or >1 million | |
Chemistry Panel
| Lab Value | Normal Range | Clinical Significance |
|---|---|---|
| BUN | 10–20 mg/dL | Elevated: renal failure, dehydration |
| Creatinine | 0.6–1.2 mg/dL | Best indicator of renal function |
| Glucose (fasting) | 70–100 mg/dL | <70 hypoglycaemia; >250 diabetic concern |
| HbA1c | <5.7% (normal) | >6.5% diagnostic for DM |
| PT/INR | PT: 11–13 sec; INR: 0.8–1.2 | INR 2–3 therapeutic on warfarin |
| aPTT | 30–40 seconds | 60–80 therapeutic on heparin |
Arterial Blood Gas (ABG) Values
| Component | Normal Range | Abnormal Direction |
|---|---|---|
| pH | 7.35–7.45 | <7.35 acidosis; >7.45 alkalosis |
| PaCO2 | 35–45 mmHg | Respiratory indicator |
| HCO3 | 22–26 mEq/L | Metabolic indicator |
| PaO2 | 80–100 mmHg | <60 respiratory failure |
| SaO2 | 95–100% | <90% critical |
🏃 Practise Lab Value NCLEX Questions
Knowing normal values is just the start. The NCLEX asks you what to do with abnormal values. Practise: Fluid & Electrolyte Questions • Renal Questions • Acid-Base Questions
Free Download: NCLEX Lab Values Cheat Sheet (PDF)
All normal ranges, critical values, and nursing implications. Printable and mobile-friendly.