Rapid Review I: Blood, Clotting, and the Kidney Panel
A laboratory requisition and result slip mock-up drawn as an original vector form, with a header block carrying collection time and specimen type, a result column, a reference column, and a flag column, six populated rows, two carrying an H flag and one carrying a CRITICAL flag with the callback line printed beneath it.
Strip 1 · Red cell mass
| Value | Range |
|---|---|
| Hemoglobin, male | 14–18 g/dL |
| Hemoglobin, female | 12–16 g/dL |
| Hematocrit, male | 42–52 % |
| Hematocrit, female | 37–47 % |
Hook: the hematocrit runs near three times the hemoglobin, so the two check each other. Transfusion is commonly considered near 7 g/dL in a stable adult.
Strip 2 · White cells and the differential
| Value | Range |
|---|---|
| White blood cells | 5,000–10,000/mm³ |
| Neutrophils | 55–70 % |
| Lymphocytes | 20–40 % |
| Monocytes | 2–8 % |
| Eosinophils | 1–4 % |
| Basophils | 0.5–1 % |
Hook: a left shift means bands are rising and the marrow is being emptied faster than it can mature cells.
Strip 3 · The neutrophil count that drives isolation
An absolute neutrophil count below 500/mm³ is severe neutropenia. Hook: the ANC, not the white cell count, decides protective precautions. A normal-looking white count with a crushed neutrophil fraction is still a neutropenic patient.
Strip 4 · Platelets
Platelets 150,000–400,000/mm³. Hook: bleeding risk climbs below 50,000/mm³, and spontaneous bleeding is the concern below 20,000/mm³.
Strip 5 · Clotting times
| Value | Range |
|---|---|
| Prothrombin time | 11.0–12.5 sec |
| INR, untreated | 0.8–1.1 |
| INR, most anticoagulated adults | 2.0–3.0 |
| INR, mechanical mitral valve | 2.5–3.5 |
| aPTT | 30–40 sec |
| aPTT, heparin therapeutic | 1.5 to 2.5 times the control value |
Strip 6 · Renal indices
| Value | Range |
|---|---|
| Blood urea nitrogen | 10–20 mg/dL |
| Creatinine | 0.6–1.2 mg/dL |
| BUN-to-creatinine ratio | 10:1 to 20:1 |
| eGFR | above 60 mL/min/1.73 m² |
| Serum osmolality | 275–295 mOsm/kg |
Strip 7 · Sugar over time
| Value | Range |
|---|---|
| Fasting glucose | 70–99 mg/dL |
| A1C, normal | below 5.7 % |
| A1C, prediabetes | 5.7–6.4 % |
| A1C, diabetes | 6.5 % or above |
Margin notea rising BUN with a flat creatinine is usually dry.
☐ ANC ☐ platelet thresholds ☐ the two INR targets
→ BOOK 01 · P31 for the master cards. → BOOK 11 · P7 for the anemias and neutropenia. → BOOK 05 · P9 for anticoagulant pharmacology.
Takeawayeach range on this page exists because it changes something you do: transfuse, isolate, hold, or call.
Reference ranges vary between institutions and reference laboratories. Follow local protocol.