Critical Values

Hematocrit Critical Values

• ≤ 21% (≤ 0.21)

• ≥ 65% (≥ 0.65)

Hemoglobin Critical Values

• ≤ 70 g/L

• ≥ 200 g/L

Reticulocyte Critical Value

>20%

WBC Count Low Critical Value

• < 2,000/uL on a new patient

• 1,000 difference from previous, if less than 4,000/uL

WBC Count High Critical Value

>50,000/uL on a new patient

Blood Smear Systemic Infection Indicator

Neutrophilic phagocytosis of microorganisms (indicating the presence of systemic infection)

Blood Smear Leukemoid Reaction

Shows abnormal leukemoid reaction

Blood Smear Hemolytic Condition Indicator

Schistocytes (may indicate hemolytic condition)

Blood Smear Critical Findings (Cells & Organisms)

• Sickle cells

• Blast forms (if never or not recently reported in the patient)

• Presence of intracellular organisms

Platelets Critical Values

• < 20,000/uL and NOT previously reported

• > 1 million/uL

Prothrombin Time Critical Value

>40 seconds