2 - Blood & Other Samples Glossary Terms

Capillary Action

The process by which blood is drawn into a small tube (like a Pasteur pipette or microhematocrit tube) without the need for active suction.

Cardiac Puncture

A terminal blood collection technique where a needle is inserted directly into the heart; it requires anesthesia and dorsal recumbency.

Hematoma

A localized swelling filled with blood caused by a break in a blood vessel; prolonged pressure is required after arterial puncture to prevent this.

Hyperthermia

An abnormally high body temperature that can be a dangerous side effect of using heat lamps or chambers to promote vasodilation.

Indwelling Catheter

A tube left inside a blood vessel for a period of time; it requires regular maintenance to prevent the formation of a thrombus.

Left Cardiac Notch

The specific anatomical area between the xiphoid process and the ribs on the animal's left side used as an entry point for cardiac puncture.

Retro-orbital Sinus

A cluster of blood vessels located behind the eye socket; a common but invasive site for blood collection in rats and mice.

Sentinel Animal

An animal used to monitor the health and disease status of a larger colony.

Serum

The clear, yellowish fluid that remains after whole blood has clotted; it makes up approximately 55% of a whole blood sample.

Superficial Temporal Vein

A vessel located in a cluster caudal to and just above the tip of the mandible (jaw bone), used for blood collection.

Terminal Procedure

A procedure, such as a terminal bleed, that results in the death of the animal; it is used when large volumes of blood (up to 1/2 of TBV) are required.

Thrombus

A blood clot that can form within a vessel or catheter, potentially blocking flow and requiring preventative maintenance in indwelling systems.

Total Blood Volume (TBV)

The total amount of blood present in an animal's body (e.g., ~2 mL in a mouse; ~5 L in a cow).

Vacutainer

A sterile glass or plastic tube with a colored rubber stopper creating a vacuum seal inside; often unsuitable for rodents due to vessel collapse.

Vasodilation

The widening of blood vessels, typically achieved through warming or physical manipulation, to increase blood flow for easier collection.

Xiphoid Process

A cartilage flap located at the base of the sternum used as a landmark for cardiac puncture.