Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Chapter 7 Blood and Blood-Forming...

transcript

Chapter 7

Blood and Blood-Forming Organs Diseases and Disorders

Anatomy and Physiology

• Hematologic system

• Major functions of blood:– Transport nutrients to cells

– Aid removal of wastes

• Average adult has 5 to 6 liters of circulating blood

Blood Components

• Erythrocytes– Normal count:

• 4.2 to 6.3 million

– Life span:• 120 days

– Form in bone marrow and do not reproduce

• Hemoglobin important in oxygen transport

• Normal hemoglobin:– Male

• 13.5 to 18 hemoglobin in grams (gm)/100 milliliter (ml)

– Female• 12 to 16 gm/100ml

• Leukocytes protect individual from infection– Normal count:

• 4,500 to 11,000

• Platelets– Also known as thrombocytes

– Important in blood clotting

– Normal count:• 150,000 to 350,000

• Blood-forming organs:– Lymph nodes

– Bone marrow

– Spleen

– Liver

• Lymph system protects against pathogens

• Bone marrow– Major blood cell producer

• Spleen produces lymphocytes, plasma cells, and antibodies to filter microorganisms from blood

• Liver produces prothrombin and fibrinogen for blood clotting

Animation

Click Here to Play Blood Animation

Common Signs and Symptoms

• Erythrocytopenia– Decrease in RBCs leading to anemia

– Symptoms:• Fatigue

• Headache

• Low RBCs

• Pallor

• Shortness of breath

• Erythrocytosis– Increased RBCs

– Symptoms:• High RBCs

• Reddened skin tones

• Bloodshot eyes

• Increased blood volume and pressure

• Increased blood volume of heart

• Leukocytopenia– Decreased white blood cells

– Weakens immune system

• Leukocytosis– Increased white blood cells

– Normal response to acute infections

• Thrombocytopenia– Decreased platelet count leading to coagulation problem

– Symptoms:• Petechiae

– Small hemorrhages in skin

• Ecchymoses– Large areas of bruising or hemorrhage

• Thrombocytopenia– Symptoms:

• Epistaxis– Nosebleeds

• Bleeding in mouth, gums, and mucous membranes

• Thrombocytosis– Increase in platelets

– Uncommon

– Usually no serious side effects

Diagnostic Tests

• Complete blood count with differential and indices

• Biopsy of blood-forming organs

• Hematocrit (Hct) reflects amount of red cell mass as proportion of whole blood

• Hemoglobin (Hgb) reflects blood’s oxygen-carrying potential

Diagnostic Tests

• Bleeding time determines platelet disorders– E.g., hemophilia, thrombocytopenia, disseminated

intravascular coagulation

• Prothrombin time (PT) and partial prothrombin time (PTT) measure blood’s ability to clot

Diagnostic Tests

• Biopsy– Bone marrow

– Lymph node

Disorders of Red Blood Cells

• Anemia– Decrease in oxygen-carrying ability of RBC

– Symptoms:• Pallor

• Fatigue

• Shortness of breath

• Anemia– Symptoms:

• Tachycardia

• Headache

• Irritability

• Syncope

• Iron deficiency anemia– Loss of iron or inadequate intake of iron

– Causes:• Blood loss

• Low dietary intake

– Treatment:• Increase dietary intake of iron

• Folic acid deficiency anemia– Folic acid needed for maturation of RBCs

– Causes:• Poor diet

• Overcooking of vegetables

• Over consumption of alcohol

– Treatment:• Increase folic acid intake by eating green and yellow vegetables

• Pernicious anemia– Lack of intrinsic factor leading to inadequate absorption of

vitamin B12

– Treatment:• Monthly injections of vitamin B12 for life

• Hemolytic anemia– Destruction of RBCs related to antibody-antigen reaction

– Disorder of immune system leading to destruction of erythrocytes

– Treatment:• Exchange transfusion and/or splenectomy

• Sickle cell anemia– Hereditary

– Found in African American race

– Abnormal sickle shape of erythrocyte• Does not allow cell to travel smoothly through vessels

– Symptomatic treatment

– No cure

• Aplastic anemia– Failure of bone marrow to produce blood components

– Causes:• Chemotherapy

• Radiation

• Viruses

• Toxins

• Aplastic anemia– Treatment:

• Avoid causative agent

• Bone marrow transplantation

• Transfusions

• Polycythemia– Too many blood cells

– Symptoms:• Enlarged spleen

• Reddened mucous membranes

• Bloodshot eyes

• Deep red color on palms

• Polycythemia– Treatment:

• Donate blood at regular intervals to reduce blood volume

Disorders of White Blood Cells

• Mononucleosis– Also known as kissing disease

• Sore throat

• Swollen glands

• Mononucleosis– Diagnosis by increased monocytes in white blood cells

(WBCs)

– Treatment:• Rest

• Analgesics

• Throat gargles

• Leukemia– Malignant neoplasm of blood-forming organs

– Abnormal production of immature leukocytes

– May be acute or chronic

– Acute forms affect children, progress rapidly, and may be fatal

• Leukemia– Chronic forms affect older adults, are often asymptomatic,

and may not be fatal

– Classified as:• Myelogenous

– Affecting bone marrow

• Lymphocytic– Affecting lymph nodes

• Leukemia– Diagnosis by bone marrow biopsy

• Headache

• Sore throat

• Leukemia– Symptoms:

• Dyspnea bleeding of mucous membranes of mouth and gastrointestinal (GI) system

• Bone and joint pain

• Enlargement of lymph nodes, liver, and spleen

– Infections common

• Leukemia– Treatment:

• Aggressive chemotherapy

• Once in remission, bone marrow transplant to replace neoplastic tissue with normal tissue

• Remission at 50 percent

• Hodgkin’s disease– Most common lymphoma

– Symptoms:• Painless enlargement of lymph nodes in neck

• Weight loss

• Fever

– Primarily affects young adults• Average age of 35

• Hodgkin’s disease– Cause thought to be viral

– Diagnosis by presence of Reed-Sternberg cell in lymphatic tissue

– Treatment:• Radiation

• Chemotherapy

– If in remission for five years or more, complete cure possible

• Non-Hodgkin’s lymphoma (NHL)– Lymphomas lacking Reed-Sternberg cell

– Symptoms:• Painless enlargement of lymph nodes of neck, axilla, and inguinal

• Fever

• Night sweats

• Weight loss

• Multiple myeloma– Malignant neoplasm of plasma cells or B-lymphocytes

– Increases with age• Peaks in 70s

– Plasma cells multiply abnormally in bone marrow• Causes weakness

• Leads to fractures and bone pain

Multiple Myeloma

• Multiple myeloma– Diagnosis by honeycombed bone pattern, hypercalcemia,

Bence-Jones protein found in blood and urine, and bone marrow biopsy

– Treatment:• Chemotherapy

• Radiation

• Not effective– Poor prognosis

Disorders of Platelets

• Hemophilia– X-linked hereditary bleeding disorder

– Several types• Type A

– Most common

– Male children from asymptomatic mothers

– Lack protein necessary for clot formation

• Hemophilia– Symptoms:

• Epistaxis

• Bruising

• Prolonged bleeding

– Diagnosis by blood test

• Hemophilia– Treatment:

• Prevention of injury

• Treat symptoms

• Blood transfusions

• Concentrated form of clotting protein

– No cure

• Thrombocytopenia– Also known as thrombocytopenia purpura

– Decrease in platelets leading to inability to normally clot blood

– Symptoms:• Abnormal bleeding in skin, mucous membranes, and internal

organs

• Petechiae

• Thrombocytopenia– Symptoms:

• Ecchymoses

• GI hemorrhages

• Epistaxis

• Hematuria

• Thrombocytopenia– Diagnosis by platelet count and bleeding time

– Treatment:• Avoid tissue trauma to reduce bleeding

• Vitamin K

• Transfusions of platelets

• Splenectomy

• Disseminated intravascular coagulation (DIC)– Abnormal clotting followed by abnormal bleeding

– Usually follows major trauma• E.g., complicated childbirth, surgery, tissue destruction,

septicemia, snakebite, shock

– Multiple clots in capillaries

– Life-threatening

• DIC– Symptoms:

• Petechiae

• Ecchymosis

• Hematoma

• Hematuria

• GI bleeding

• DIC– Symptoms:

• Hematemesis

• Blood in stool

– Treatment:• Heparin

• Platelets

• Rare diseases– Thalassemia

• Primarily affects people of Mediterranean descent

• Fragile, thin RBCs form defective hemoglobin

• Rare diseases– von Willebrand’s disease

• Hereditary

• Congenital

• Deficiency in clotting factor and platelet function

• Also known as angiohemophilia

• Affects females and males

Effects of Aging

• Age-related changes in other systems (e.g., immune, digestive) leave older adults more susceptible to infections and nutritionally related blood disorders

• Decreased iron

• Poor nutrition

Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Chapter 7 Blood and Blood-Forming...

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