Need clarity before I build
When a patient presents with cardiac or bleeding concerns, five laboratory values frame every decision you will make: WBC, Hgb/Hct, Platelets, Troponin, and D-dimer. WBC trends alert you to infection that could destabilize an already compromised heart; hemoglobin and hematocrit reveal whether oxygen delivery is threatened; platelets predict bleeding or clotting potential; troponin confirms or rules out myocardial injury; D-dimer tells you if fibrin is being actively digested somewhere in the body.
Interpreting the pattern—rising, falling, or stable—matters more than memorizing an isolated number, because treatment hinges on whether the problem is production, destruction, or consumption of cells and proteins.
Test | Adult Reference Range | What a Dangerous Shift Implies |
---|---|---|
WBC | 4.5–11.0 × 10³/μL | ↓ immunosuppression ↑ infection/inflammation |
Hgb | 12–16 g/dL (F) 14–18 g/dL (M) |
↓ anemia → tissue hypoxia ↑ polycythemia → hyperviscosity |
Hct | 36–44% (F) 42–52% (M) |
↓ bleeding/fluid overload ↑ dehydration/polycythemia |
Platelets | 150–400 × 10³/μL | ↓ bleeding risk ↑ thrombosis risk |
Troponin | <0.04 ng/mL | ↑ myocardial injury (MI, myocarditis) |
D-dimer | <0.5 μg/mL | ↑ active clot breakdown (PE, DVT, DIC) |
The ED receives four new admissions within twenty minutes. Each patient has preliminary vitals and stat labs drawn on arrival.
For each patient, choose the most urgent intervention:
A. Transfuse PRBCs
B. Transfuse FFP (plasma)
C. Transfuse platelets
D. Infuse 0.9% saline bolus
E. Begin broad-spectrum antibiotics and saline
Answer Key
1. American Heart Association. (2020). Advanced Cardiovascular Life Support Provider Manual.
2. Ignatavicius, D. D., Workman, M. L., & Rebar, C. R. (2021). Medical-Surgical Nursing: Concepts for Interprofessional Collaborative Care (10th ed.).
3. Lippincott Williams & Wilkins. (2022). Lippincott Nursing Drug Guide.
4. National Heart, Lung, and Blood Institute. (2022). Clinical Guidelines on Anticoagulation Therapy.
5. Silvestri, L. A. (2022). Saunders Comprehensive Review for the NCLEX-RN Examination (9th ed.).