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The values and rules that recur on the CMSRN. Skim before test day, then prove it with practice.
Exam facts
- 150 questions (125 scored), 3 hours; pass ≈ 71% (standard score 95)
- Biggest domain: Patient/Care Management (32%)
Normal lab values to know cold
| Lab | Normal |
|---|---|
| Sodium | 135–145 mEq/L |
| Potassium | 3.5–5.0 mEq/L |
| Calcium | 8.5–10.5 mg/dL |
| Glucose (fasting) | 70–110 mg/dL |
| Creatinine | 0.6–1.2 mg/dL |
| Hemoglobin | 12–18 g/dL |
| Platelets | 150,000–400,000 |
| INR (no anticoagulation) | 0.8–1.1 |
Prioritization frameworks
- ABCs — airway, breathing, circulation come first
- Maslow — physiologic needs before psychosocial
- Acute > chronic, unstable > stable, unexpected > expected
Safety quick hits
- Suspected transfusion reaction → stop the transfusion, keep IV open with saline
- Delegate only stable, routine tasks to UAP — never assessment, teaching, or evaluation
- In DKA, insulin shifts potassium into cells — monitor and replace potassium
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Sources & references
The exam facts on this page are drawn from official certifying-body materials, reviewed 2026-06-18 by the DrCertifications exam-prep team (10+ years in exam preparation and publishing).