Volume 3 - Chapter 9 - Hematology

Front 1

Hematopoiesis in Adults

Back 1

- occurs exclusively in the bone marrow unless a pathological state exists

Front 2

Erythropoietin

Back 2

- the hormone responsible for red blood cell production
- produced by the kidneys and liver

Front 3

Unipotent Progenitors

Back 3

- mature into basophils, eosinophils, neutrophils, monocytes, erythrocytes, thrombocytes

Front 4

Liver and Hematopoiesis

Back 4

- liver also removes toxins from the blood and produces many clotting facotrs and proteins in the plasma

Front 5

Pluripotent Stem Cells

Back 5

- may differentiate into common lymphoid stem cells that mature into lymphocytes

Front 6

Spleen and Hematopoiesis

Back 6

- an important part of the immune system
- have cells that scavenge abnormal blood cells and bacteria

Front 7

Blood Volume

Back 7

- remains constant - 6% of body weight
- average of 80-85 ml of blood/kg of body weight
- body can handle up to 0.5L of lost blood or fluid easily
- major determinants are red cell mass and plasma volume

Front 8

Red Blood Cells and Blood Volume

Back 8

- remain confined to the intravascular compartment
- if destruction remains constant, then only rate of production can alter the size of circulationg red blood cell mass
- differs from blood plasma

Front 9

Blood Plasma and Blood Volume

Back 9

- can rapidly change due to fluid shifts between the intravascular and extravascular space
- shifts help to preserve circulating blood volume in the event of acute hemorrhage

Front 10

Other Compensatory Measures for Blood Volume

Back 10

- vasoconstriction
- tachycardia
- increased cardiac contractility
- maintains adequate perfusion until significant losses overwhelm
- then the patient enters decompensated shock
- young, healthy bodies can compensate for as much as 25 to 30% blood volume loss

Front 11

Components of Blood

Back 11

- liquid (plasma)
- formed elements (RBC, WBC, platelets)

Front 12

Plasma

Back 12

- thick, pale yellow fluid that makes up the liquid part of the blood
- 90 to 92% water
- 6-7% proteins
- 2-3% fats, carbohydrates, gases and certain chemical messengers
- transports the cellular components of blood and dissolved nutrients throughout the body
- transports waste products from cellular metabolism to the liver, kidneys, and lungs (where they are removed from the body)
- performs a role in gas transport
- oxygen and carbon dioxide are carried by RBCs and dissolved and transported in plasma

Front 13

Osmotic Pull

Back 13

- also called oncotic pressure
- components can move back and forth across the capillary membranes to the interstitial fluid
- plasma proteins (Albumin) are large molecules - difficult to diffuse across the membranes
- helps to retain water in the capillaries

Front 14

Plasma Protein Functions

Back 14

- clotting of blood
- dismantling of clots
- buffering of the blood's acid-base balance
- transporting hormones and regulating their effects
- providing a source of energy

Front 15

Electrolytes

Back 15

- found in plasma
- chemical substances that dissociate into charged particles in water
- essential for nerve conduction, muscle contraction, and water balance
- can easily diffuse across capillary membranes (based on concentration gradient)

Front 16

Carbohydrates

Back 16

- in plasma they are generally in the form of glucose (primary energy source of all body tissues)
- important to brain cells as they cannot obtain energy from fat metabolism
- glucose cannot diffuse across most cell membranes without assistance from the hormone insulin

Front 17

Hematology

Back 17

- the study of the blood and blood-forming organs
- include RBC, WBC, platelet and coagulation disorders
- usually accompany ongoing disease processes
- may predispose patients to infection and intolerance to exercise, hypoxia, acidosis and blood loss

Front 18

Signs and Symptoms of a Hematological Disorder

Back 18

- they do not point directly to a specific disease process
- laboratory findings may be necessary to further classify the diagnosis
- recognize and treat injuries, pain and instabilities

Front 19

Pluripotent Stem Cell

Back 19

- a cell from which the various types of blood cells can form
- cellular components of blood are formed by the differentiation of theses cells (hematopoeisis)

Front 20

Hematopoiesis

Back 20

- the process through which pluripotent stem cells differentiate into various types of blood cells
- the stem cell reproduces to maintain a constant population of cells
- some differentiate into myeloid multipotent stem cells, that differentiate into unipotent progenitors

Front 21

Hematopoietic System

Back 21

- consists of blood (cells and plasma)
- bone marrow
- liver
- spleen
- kidneys

Front 22

Hematopoiesis in Fetuses

Back 22

- first extramedullary hematopoeisis
- occurs outside the bone marrow
- in the liver, spleen, lymph nodes, and thymus
- after 4 months becomes intramedullary hematopoiesis
- developing bone marrow begins to produce blood cells

Front 23

Hematopoiesis After Birth

Back 23

- bone marrow is the primary site of blood cell production and extramedullary hematopoiesis greatly diminishes (mostly occurs in liver and spleen)