6- Blood Physiology & Pathology

Hematopoiesis

blood cell formation

plasma

Liquid part of blood

formed elements

red blood cells, white blood cells, platelets

complete blood count (CBC)

Determination of numbers of blood cells, hemoglobin concentration, hematocrit, and red cell values-MCH, MCV, MCHC

What percentage of blood is plasma and blood cells?

55% plasma, 45% erythrocytes, <1% buffy coat

Leukocytes

WBC, fight infection

Lymphocytes

A type of white blood cell that make antibodies to fight off infections

T-cells

Cells created in the thymus that assist with immune response

B-cells

agranulocytes that produce antibodies, recognize and eliminate foreign materials

Monocytes

agranular leukocyte that migrates into tissues and transform into a macrophage

Granulocytes

Engulf and destroy foreign material including bacteria

neutrophils

WBC that indictates the ability to fight bacterial infections

Eosinophils do what?

Targets parasites

Basophils do what?

Targets allergens

________ indicate the ability to fight bacterial infections

Neutrophils

Neutropenia

deficiency of neutrophils

Red blood cells

Blood cells that carry oxygen from the lungs to the body cells.

Hemoglobin

-An iron-containing protein in red blood cells that reversibly binds oxygen

-Levels are reported in absolute amounts in g/100 mL or g/dL. Normal range varies, generally 10-15 g/dL

Hematocrit

-Percentage of whole blood that is composed of RBCs

-Can be an indicator of blood viscosity

-Higher than 50% is bad in adults

Platelets

cell fragments in the blood that play a crucial role in blood clotting

throbocytopenia

low platelet count

Thrombocytosis

an abnormal increase in the number of platelets in the circulating blood

Erythrocyte

mature RBC, carry O2 to tissues, carry CO2 to lungs, a buffer to maintain acid/base balance

Oxygen capacity

The maximum amount of oxygen an individual's blood can carry; this capacity depends on the amount of hemoglobin available

What is normal Hb content?

14.0 g/dL for adult females and 15.5 g/dL adult males

What does a L shift mean in the oxyhemoglobin dissociation curve?

Increased affinity; happens in central vasculature

What does a R shift mean in the oxyhemoglobin dissociation curve?

Decreased affinity; happens in peripheral vasculature

Anemia

A condition in which the blood is deficient in red blood cells, in hemoglobin, or in total volume.

iron deficiency anemia

anemia caused by inadequate iron intake

Aplastic anemias

destruction or inhibition of red bone marrow

Chronic disorders of hemoglobin

Sickle cell, thalassemia

Hemolytic anemias

insufficient iron in blood due to destruction of RBC resulting from genetic blood diseases, toxins, or infectious pathogens

Acute blood loss anemia

reduction in red blood cells as a result of hemorrhage

Sickle Cell Disease (SCD)

group of inherited, autosomal recessive disorders characterized by the presence of an abnormal form of hemoglobin in the erythrocyte

Vaso-occlusion

Blockage of blood vessels by sickled cells.

Hemolysis

the rupture or destruction of red blood cells.

What is a hallmark of sickle cell disease?

Acute pain

Acute crises of SCD

-acute chest syndrome

-acute stroke

-hepatic sequestration

-splenic sequestration

-retinopathy

General signs and symptoms of SCD

Pain, fatigue, shortness of breath, exercise intolerance

Treatment for SCD

Hydroxyurea (increases HbF) and bone marrow transplantation.

Hemophilia

disease where blood doesn’t coagulate to stop bleeding

Hemophilia A

Factor VIII deficiency

Hemophilia B

Factor IX deficiency

Intrinsic pathway is inhibited by _________

damage to vessel wall

Extrinsic pathway is a

response to trauma to extravascular cells

Signs and symptoms of hemophilia

-Recurrent bleeding in soft tissue, muscle, joints (hemarthrosis)

-Joint contractures

-Joint deformities

Treatment for hemophilia

-Factor replacement

-transfusion

-antrifibrinolytic drugs

Leukemias

Characterized by overcrowding of WBCs and less production of RBCs

Acute Myeloid Leukemia (AML)

Immature granulocytes predominate. Platelets and erythrocytes are diminished because of infiltration and replacement of the bone marrow by large numbers of myeloblasts.

Chronic Myeloid Leukemia (CML)

Malignant but mature granulocytic leukocytes multiply in bloodstream

Acute Lymphocytic Leukemia (ALL)

Immature lymphocytes (lymphoblasts) predominate. This form is seen most often in children and adolescents; onset is sudden

Chronic Lymphocytic Leukemia (CLL)

abnormal numbers of relatively mature lymphocytes predominate in the marrow, lymph nodes, and spleen

Clinical manifestations of leukemias

Anemia, severe infections, increased metabolic rate, headache and disorientation, hyperuricemia, splenomegaly or hepatomegaly, lyphadoenopathy and bone pain

Lymphomas

tumors from cells of the lymphatic system

Hodgkin's lymphoma

Characterized by the presence of Reed-Sternberg cells

Non-Hodgkin's Lymphoma

malignant cancer that starts in the lymphocytes

Clinical manifestations of lymphomas

-Irregular behavior or fever

-Jaundice

-Splenomegaly or hepatomegaly

-Anemia

-Respiratory symptoms

-Bone pain

Myelosuppression

suppression of the blood cell-producing function of the bone marrow

Myelosuppression of platelets leads to _______

bruising or hemorrhaging

Myelosuppression of WBCs leads to _______

higher risk for infection

Myelosuppression of RBCs leads to __________

fatigue