Pathophysiology - Lecture 11 - Blood & Circulatory Disorders - Blood therapy and Anemia

Tunica Intima

endothelium (simple squamous epithelium)

Tunica Media

middle layer, mostly smooth muscle

Tunica Adventitia (externa)

connective tissue with fibrocytes, collagen, and elastic fibers

Hemopoiesis

blood forming tissue

Erythrocytes (RBCs)

-contains hemoglobin

-life span of 120 days

Hemoglobin

-globin portion

-heme group

Platelets (Thrombocytes)

blood clotting

Blood clotting

-AKA coagulation

-seal up the hole

What does the 13 different clotting factors convert?

circulating (soluble) fibrinogen into insoluble fibrin

Fibrin

protein fibers that extend from platelet

Vitamin K

-needed for proper clotting

-helps make 4 different clotting factors

Extrinsic Pathway

factors released by damaged tissues begin cascade

Intrinsic Pathway

cascade of clotting factors leading to the formation of a clot within an injured vessel

Extrinsic factor and intrinsic factor lead to which common pathway?

factor 10

Prothrombinase

converts prothrombin to thrombin

Thrombin

converts fibrinogen to fibrin

ABO blood system

-based on the presence or absence of specific antigens

-antibodies in the blood plasma

Rh system

-antigen D in plasma membrane is RH+

-Absence of Antigen D is RH-

Hematocrit

-percent by volume of RBCs in blood

Low Hematocrit

fluid overload

High Hematocrit

dehydration

Hemoglobin

Oxygen carrying pigment in red blood cells

MCV (mean corpuscular volume)

oxygen-carrying capacity of blood of hemoglobin

Reticulocyte Count

Assessment of bone marrow function

Prothrombin Time (PT) and partial thromboplastin time (PTT)

Measure function of various factors in coagulation process (or coagulation abilities). INR is a standardized version

INR

international normalized ratio

Epoetin alfa for blood therapies

-Artificial form of erythropoietin

-before certain surgical procedures

-anemia related to cancer

-chronic renal failure

Bone marrow or stem cell transplantation for blood therapies

-close tissue match necessary

-tx of some cancers

-severe immunodeficiency

-severe blood cell diseases

Drug tx for blood therapies

-prevent or aid in the clotting process

EPO

-erythropoietin

-increase RBC formation

-athletes cheat with taking this

Anemia

-a reduction in oxygen transport

-basic problem is hemoglobin deficit

Oxygen deficit leads to

-less energy production in all cells

-compensation mechanism

-general signs of anemia

less energy production in all cells leads to what?

reduced cell metabolism and reproduction

compensation mechanism

tachycardia and peripheral vasoconstriction

general s/s of anemia

-fatigue

-pallor (pale face)

-dyspnea

-tachycardia

Oxygen deficit leads to what?

decreased regeneration of epithelial cells

visceral organs that get affected by oxygen deficit

-digestive tract becomes inflamed and ulcerated

-dysphasia (swallowing)

-hair and skin may show degenerative changes

-esophageal webs (flaps)

Severe anemia may lead to what?

-angina

-CHF

Angina

Pain in the heart region caused by lack of oxygen

CHF

congestive heart failure

5 different Anemias

-Iron deficiency anemia

-Pernicious Anemia

-Aplastic Anemia

-Sickle cell Anemia

-Hemolytic Anemia

Iron Deficiency Anemia

-Insufficient iron impairs hemoglobin synthesis

-Microcytic

-Hypochromic RBCs

Microcytic RBCs

Smaller than normal red blood cells.

Hypochromic RBCs

Red blood cells with reduced hemoglobin content.

Common facts about Iron Deficiency Anemia

-very common

-ranges from mild to severe

-occurs in all age groups

-pregnant women are more prone

-frequently sign of an underlying problem

Causes of iron deficiency anemia

-dietary intake (rare)

-chronic blood loss

-impaired duodenal absorption of iron

-severe liver disease

s/s iron deficiency anemia

-pallor of skin and mucous membranes

-dyspnea

-fatigue

-tachycardia

-cold intolerance

-irritability

-degenerative changes

-stomatitis and glossitis

-menstrual irregularities

-delayed healing

Pernicious Anemia

Vitamin B12 deficiency

Why Vitamin B12 deficiency?

affect parietal cells which affects ability to secrete intrinsic factors which will not allow B12 absorption, which leads to pernicious anemia

What often accompanies pernicious anemia?

chronic gastritis

What does parietal cells secrete?

-HCl and intrinsic factor

HCl

hydrochloric acid, strong acid found in the gastric (stomach) tract

Hypochlorhydria

abnormally low gastric acid secretions

Achlorhydria

Absence of hydrochloric acid from the gastric juice.

What affect does deficit of vitamin have on the nervous system?

-Feeling of pins and needles

-tingling in limbs

-symptoms in the peripheral nerves

Aplastic Anemia

impairment or failure of bone marrow

Causes of aplastic anemia

-myelotoxins

-viruses

-genetics

-myelodysplastic syndrome

-diseases

aplastic anemia affects the person for how long?

-temporary

-permanently

-can be life threatening

Myelotoxins

-radiation

-industrial chemicals

-drugs

Myelodysplastic syndrome

compromised bone marrow

What would blood counts indicate for aplastic anemia?

-penia on all blood cell type

What kind of biopsy may be required for aplastic anemia?

bone marrow biopsy

How do erythrocytes appear in aplastic anemia?

normal

Why is it imperative to identify cause and prompt treatment for aplastic anemia?

-life threatening

-removal of any bone marrow suppressants

-for bone marrow recovery

Hemolytic Anemia

results from excessive destruction of RBCs

Causes of Hemolytic anemia

-genetic

-immune reactions

-changes in blood chemistry

-infections (i.e. malaria)

-Toxins in the blood

-Antigen-antibody reactions

Antigen-Antibody reactions in hemolytic anemia

-incompatible blood transfusion

-hemolytic disease of newborn (Erythroblastosis fetalis)

Sickle Cell Anemia

-Genetic condition

-homozygous recessive

-Autosomal

-Incomplete dominance

-African ancestry

What is abnormal is sickle cell anemia?

abnormal hemoglobin

When does a sickle cell crisis occurs?

whenevery oxygen levels are lowered

What is altered and changes shape in sickle cell anemia?

altered hemoglobin is unstable and changes shape in hypoxemia

Why can't sickle cell anemia pass through the microcirculation?

sickle-shaped cells are too large to pass through the microcirculation

Obstruction leads to what in sickle cell anemia?

obstruction leads to multiple infarctions and areas of necrosis

When does the shape of sickle cell occur?

when the sickle cell gives off oxygen is when it changes shape to a sickle shape

When do clinical sign of sickle cell anemia show?

clinical signs do not usually appear until the child is about 12 months old

Why do sickle cell anemic patients become jaundiced?

high rate of hemolysis

hyperbilirubinemia

excessive bilirubin in the blood

s/s of sickle cell anemia

-severe pain

-pallor

-weakness

-tachydardia

-dyspnea

-hyperbilirubinemia

-splenomegaly

-vascular occlusions

-delay of growth and development

-CHF

Why do sickle cell anemic patients have severe pain?

severe pain because of ischemia of tissue and infarction

Dx for sickle cell anemia

-blood test

-Prenatal DNA analysis

Tx for sickle cell anemia

-droxia

-hydrea

-they are able to cure sickle cell anemia