Lab values master card I: hematology and coagulation
Eight stacked band gauges with a normal zone in the middle, shoulders at each side, and a shaded danger cap on only the end that actually kills.
Ranges vary by institution and by assay. Learn each value with the direction that hurts attached to it.
Strip 1 · White blood cells 5,000 to 10,000 per cubic millimeter. The absolute neutrophil count matters more than the total: below 500 per cubic millimeter, a fever is an emergency, not an observation.
Strip 2 · Hemoglobin 14 to 18 grams per deciliter in males, 12 to 16 in females. Symptomatic anemia shows up as tachycardia and exertional dyspnea long before anyone notices pallor.
Strip 3 · Hematocrit 42 to 52 percent in males, 37 to 47 in females. It runs roughly three times the hemoglobin, which is a fast sanity check on a reported panel.
Strip 4 · Platelets 150,000 to 400,000 per cubic millimeter. Below 50,000 there is bleeding risk with procedures. Below 20,000 bleeding happens spontaneously. Bleeding precautions are nursing-initiated and need no order.
Strip 5 · Prothrombin time and international normalized ratio Prothrombin time 11 to 12.5 seconds. International normalized ratio 0.8 to 1.1 untreated, 2 to 3 therapeutic for most warfarin indications. This is the warfarin value.
Strip 6 · Activated partial thromboplastin time 30 to 40 seconds, therapeutic at 1.5 to 2.5 times the control value. This is the unfractionated heparin value.
Strip 7 · The antidote pairing Vitamin K restores warfarin. Protamine sulfate reverses heparin. Learn them as a pair, and get the dosing from → BOOK 05 · P13.
Strip 8 · Erythrocyte sedimentation rate and D-dimer Nonspecific inflammation and clot breakdown, respectively. Both are sensitive, neither is diagnostic on its own.
Margin notelearn the direction that hurts, not both.
Watch outplatelets under 20,000 per cubic millimeter is a bleeding emergency with no injury required.
Takeawaymemorize each value with its dangerous direction attached, because the exam never asks for a number by itself.
Drilled version → BOOK 07 · P5.