Basic Laboratory Values with Hematology and Chemistry

Vocabulary practice flashcards covering hematology reference ranges, clinical chemistry, blood smear techniques, panic values, coagulation studies, sample integrity conditions, and urinalysis testing.

Hematology

The study of blood and blood-forming tissues, which also encompasses the area of hemostasis (coagulation).

Plasma

The liquid portion of blood, forming one of the two main components of blood alongside the cellular portion.

Buffy Coat

The thin white middle layer containing white blood cells (WBCs) and platelets that separates plasma from red blood cells after blood centrifugation.

Complete Blood Count (CBC)

An automated laboratory test performed on whole blood that is the most commonly ordered hematology test.

Red Blood Cell Count

A test determining the total number of circulating erythrocytes, used to diagnose conditions such as anemia and erythrocytosis. Reference ranges are $3.8\text{--}5.2 \times 10^6/\text{mm}^3$ for women, $4.4\text{--}5.9 \times 10^6/\text{mm}^3$ for men, $3.8\text{--}5.5 \times 10^6/\text{mm}^3$ for children under 12, and $4.0\text{--}5.8 \times 10^6/\text{mm}^3$ for newborns.

White Blood Cell Count

A test determining the total number of leukocytes without specifying individual cell types, used to diagnose leukocytosis and leukopenia. Normal ranges are $4,500\text{--}11,000/\text{mm}^3$ for adults, $6,000\text{--}14,000/\text{mm}^3$ for children under 12, and $9,000\text{--}30,000/\text{mm}^3$ for newborns.

Hemoglobin

An iron-containing protein in blood that transports oxygen ($\text{O}_2$) and carbon dioxide ($\text{CO}_2$). Normal ranges are $12\text{--}16\text{ g/dL}$ for women and $14\text{--}18\text{ g/dL}$ for men.

Hematocrit

A measurement, also called packed cell volume (PCV), that compares the volume of red blood cells to the volume of whole blood. Normal ranges are $35\text{--}47\%$ for women, $40\text{--}52\%$ for men, $34\text{--}42\%$ for 6-year-olds, $32\text{--}38\%$ for 1-year-olds, and $51\text{--}61\%$ for newborns.

Platelet Count

A test determining the quantity of platelets in peripheral circulation, used to diagnose bleeding disorders, thrombocytosis, thrombocytopenia, and monitor anticoagulant therapy (Coumadin and heparin). Normal range is $150,000\text{--}400,000/\text{mm}^3$.

Blood Smear Preparation Quality

The procedural standard for blood smear preparation, where a correct smear (Slide D) forms a thumbprint shape with a rainbow feathered edge, while improper techniques create irregular or truncated smears (Slides A, B, and C).

Differential Leukocyte Count

A test reported as percentages that determines the amount of each leukocyte type (Neutrophils $54\text{--}62\%$, Lymphocytes $20\text{--}40\%$, Monocytes $4\text{--}10\%$, Eosinophils $1\text{--}3\%$, Basophils $0\text{--}1\%$), which must be prepared within one hour of collection to preserve cell morphology.

Erythrocyte Sedimentation Rate (ESR)

A test measuring the rate at which red blood cells settle to the bottom of a tube under controlled conditions, used to monitor inflammation and tissue injury. Normal ranges are $0\text{--}10\text{ mm/hr}$ for men and children, and $0\text{--}20\text{ mm/hr}$ for women.

Lactic Acid Test

A clinical chemistry evaluation where elevated lactate (hyperlactatemia) indicates lactic acidosis, commonly found in severe sepsis or septic shock. Normal ranges are $0.7\text{--}2.5\text{ mmol/L}$ for adults and $1.1\text{--}3.5\text{ mmol/L}$ for children.

StatStrip Lactate Analyzer

A point-of-care handheld device designed to measure blood lactate concentrations.

Panic Values

Significantly abnormal laboratory test results that signal a potentially life-threatening patient condition and must be communicated directly to the physician or designated staff, typically via telephone.

Coagulation Studies

A group of four principal tests used to assess hemostasis: Platelet count, Bleeding Time, PT (Prothrombin time/protime), and aPTT/PTT (activated partial thromboplastin time).

Clinical Chemistry Department

The largest and busiest laboratory department, performing automated chemical analyses mostly on serum specimens collected in tiger top or gold tubes.

Hemolyzed Sample

A damaged blood specimen exhibiting a red discoloration in the serum/plasma portion, rendering it unsuitable for chemical testing.

Icteric Sample

A blood specimen exhibiting a brown or green discoloration due to elevated bilirubin, making it unsuitable for testing.

Lipemic Sample

A blood specimen showing a white or milky appearance due to high lipid levels, making it unsuitable for chemical testing.

Profile (Panel)

A grouped battery of related clinical chemistry tests ordered together, such as a Lipid Profile or Anemia Panel.

Routine Urinalysis

A diagnostic procedure consisting of three distinct evaluative parts: physical examination, chemical analysis, and microscopic examination.

Physical Examination of Urine

The part of routine urinalysis that assesses physical properties including turbidity, color, odor, and specific gravity.

Chemical Analysis of Urine

The part of routine urinalysis that screens for pH, protein, glucose, ketones, blood, bilirubin, urobilinogen, nitrates, and leukocyte esterase using reagent strips.