Blood Components

Red blood cells are also called…

Erythrocytes

Main functions of RBCs

• Carries oxygen to body tissues using Hgb

• Transports CO2

• Blood buffer pH

What is hemoglobin

Oxygen-carrying protein in RBCs

Lifespan of an RBC

100-120 days

Where are RBCs broken down

Spleen, liver, bone marrow

What is erythropoiesis

Production of RBCs

What organ is involved in erythropoiesis regulation

Kidneys

What is anemia / erythropenia

Too few RBCs

What is polycythemia

Too many RBC’s, making blood more viscous

What causes / is associated with polycythemia

• Polycythemia vera

• High altitude

• COPD

Polycythemia vera

Disorder involving excessive RBC production in bone marrow

How does chronic hypoxia affect RBC production

It may increaseRBC production to improve oxygen delivery to tissues

do RBCs have a nucleus

No, they are anucleate

What shape are RBCs

binconcave-shaped disks

MCV

Mean corpuscular volume (size of an RBC)

MCHC

Mean corpuscular hemoglobin concentration (amount/concentration of Hgb in each RBC)

Normal RBC count in men

4.2 - 5.4 c/mL

Normal RBC count in women

3.6 - 5.0 c/mL

Function of WBCs

Defend the body against infection (“first responders”)

Leukopenia

Decreased WBC count

Leukocytosis

Increased WBC count

Leukemia

Blood cancer that causes uncontrollable / unlimited production of WBCs

Platelets are also called…

thrombocytes

Where are platelets found?

Blood plasma

Function of platelets

Clot formation, repair damaged blood vessels

Thrombocytopenia

Too few platelets; increases bleeding risk

Thrombocytosis

Too few platelets; associated with abnormal clotting

What are megakaryocytes

Bone marrow cells responsible for maturing and releasing platelets

What is platelet plugging / aggregation

Platelets adhere to a damaged blood vessel and temporarily plug it

Plasma helps regulate…

BP and body temperature

What is plasma

The liquid surrounding blood cells (approx. 90% water)

Hematopoiesis

Production of red blood cells

What regulates blood cell formation

• Growth factor hormones

• Cytokines

• Kidneys (erythropoiesis)

How do cytokines and growth factor affect blood cell development

Their signals communicate with bone marrow, directing stem cells to mature/differentiate into thrombocytes, erythrocytes, or leukocytes

What is a CBC

Complete blood count, gives information about blood cells and helps clinicians recognize problems like anemia, infection, low platelet counts, etc.

RBC count measures…

The number of red blood cells

WBC count measures…

The number of white blood cells

What does Hct measure?

The proportion of blood make up of RBCs

What does Hgb measure?

The amount of oxygen-carrying protein (hemoglobin)

MCV on a CBC measures…

Average size of an RBC

MCHC on a CBC measures…

The average concentration of Hgb inside RBCs

What is a WBC differential

A breakdown of different types of WBCs

What does ESR stand for?

Erythrocyte sedimentation rate

What does ESR measures

How quickly RBCs settle at the bottom of a tube

What is ESR used to assess

Levels of nonspecific inflammation in the body

Why can RBCs settle faster during inflammation/infection

RBCs stick together, forming heavier clumps that sink faster

What conditions may elevate ESR

• Infections

• Certain cancers

• Autoimmune disorders

ESR range for males

0-15 mm/hr

ESR range for females

0-20 mm/hr