Collection of Blood Samples

Vocabulary practice flashcards covering the methods, terminology, anatomical sites, and clinical precautions associated with blood specimen collection.

Asepsis

The condition of being free from septic or infectious material, such as bacteria and viruses.

Blood Sample

A small amount of blood (a few drops or a few milliliters) collected from a person to aid in the diagnosis and/or prognosis of a disease or disorder.

Capillary Blood

Blood obtained from a skin puncture (skin-prick) with a lancet or needle when small quantities are needed for tests such as cell counts or hemoglobin estimation.

Venous Blood

Blood obtained by puncturing a superficial vein with a syringe and needle when larger volumes are required for complete hematological and biochemical investigations.

Arterial Blood

Blood drawn by puncturing an artery (such as the radial or femoral artery) with a syringe and needle for specialized investigations such as blood pH and blood gas analysis.

Cerebrospinal Fluid (CSF)

The biological liquid that surrounds the brain and spinal cord, analyzed in clinical laboratories.

Synovial Fluid

A biological fluid located within joints that can be analyzed in clinical laboratories.

Amniotic Fluid

The biological fluid that surrounds a developing fetus.

Chorionic Villus Sampling

A clinical sampling procedure where cells are extracted from the placenta and tested for genetic defects.

Clotted Sample

A blood sample containing clots, even microscopic ones in anticoagulated blood, that negates test results and renders the specimen unsuitable for hematological analysis.

Hemolysed Sample

A blood sample in which erythrocytes have ruptured during collection or handling, releasing hemoglobin that turns the plasma or serum red and invalidates test results.

Plasma

The liquid component of blood obtained by centrifuging anticoagulated blood (representing whole blood minus all blood cells).

Serum

The clear liquid expressed after whole blood clots without anticoagulant (representing plasma minus fibrinogen and all clotting factors).

Tourniquet

An elastic bandage or rubber strip applied $4\text{ to }6\text{ inches}$ ($10\text{ to }15\,\text{cm}$) above the puncture site to obstruct venous return and distend veins for venipuncture.

Prolonged Venous Occlusion

Extended stasis from tourniquet application causing increased concentrations of total protein, iron, cholesterol, AST, bilirubin, and CK, alongside decreased serum potassium.

Fist Pumping

Repeated clenching of the hand before venipuncture, an action that must be avoided because it falsely increases plasma potassium, phosphate, and lactate concentrations.

Diurnal Variation

Cyclical daily fluctuations in the concentration of blood constituents (such as iron, growth hormone, and cortisol) that make the timing of blood collection essential.

Thixotropic Polymer Gel

An inert substance with a specific gravity of $1.04$ found in separator tubes that shifts during centrifugation to form a barrier disk between blood cells and supernatant.

Evacuated Blood Collection Tubes

Vacuum-sealed blood tubes that are less expensive, more convenient, and easier to handle than traditional syringes.

Skin-Prick Sites

Recommended anatomical puncture sites for capillary blood collection, including the sides of fingertips in adults (middle and ring fingers) and the medial or lateral plantar surfaces of the heel in infants.

Earlobe Prick

A skin-prick method for capillary blood collection where blood is expressed from the earlobe and collected using a capillary tube.