Introduction To The Blood And Lymph System PDF

**I. Introduction to the Blood and Lymphatic Systems** - **Anemia** - Condition characterized by a reduction of red blood cells, a deficiency of hemoglobin and hematocrit in the blood, or an increased destruction of red blood cells. - Reduction in red blood cells lea...

**I. Introduction to the Blood and Lymphatic Systems** - **Anemia** - Condition characterized by a reduction of red blood cells, a deficiency of hemoglobin and hematocrit in the blood, or an increased destruction of red blood cells. - Reduction in red blood cells leads to a decreased oxygen-carrying capacity. - **Disseminated Intravascular Coagulation (DIC)** - Grave coagulopathy resulting from the overstimulation of normal clotting and clot dissolution processes in response to disease or injury. - Can be caused by septicemia, obstetrical complications, malignancies, tissue trauma, transfusion reactions, burns, shock, and snake bites. - **Erythrocytosis** - Abnormal increase in the number of circulating red blood cells and increased production of granulocytes and platelets. - **Hemarthrosis** - Bleeding into a joint space. - **Hemophilia A** - Absence of anti-hemophilic factor VIII, which is essential for the conversion of prothrombin to thrombin through the intrinsic clotting pathway. - **Heterozygous** - Having two different genes. - **Homozygous** - Having two identical genes inherited from each parent for a given hereditary characteristic. - **Idiopathic** - Cause is unknown. - **Leukemia** - Malignant disorder of the hematopoietic system where an excess of leukocytes accumulates in the bone marrow and lymph nodes. - **Leukopenia** - Extremely low white blood cell count. - **Lymphangitis** - Inflammation of one or more lymphatic vessels or channels, usually resulting from an acute streptococcal or staphylococcal infection in an extremity. - **Lymphedema** - Primary or secondary disorder characterized by the accumulation of lymph fluid in soft tissue, resulting in edema. - **Multiple Myeloma** - Malignant neoplastic immunodeficiency disease of the bone marrow. - **Pancytopenia** - Reduction or absence of all three major blood elements (red blood cells, white blood cells, and platelets) from the bone marrow. - **Pernicious** - A condition capable of causing great injury, destruction, or death unless treated. - **Reed-Sternberg Cell** - Atypical histiocytes consisting of large, abnormal, multi-nucleated cells in the lymphatic system found in Hodgkin\'s disease. - These cells increase in number and replace normal cells. - **Thrombocytopenia** - Platelet count below 100,000 mm3. **II. Overview of the Hematologic and Lymphatic Systems** - The hematologic and lymphatic systems are vital for maintaining homeostasis. - Diseases and disorders affecting these systems can cause problems in other body systems. - **Blood** - Transports oxygen to cells, removes waste products from cells, and delivers nutrients throughout the body. - **Lymphatic System** - Filters harmful substances out of the fluid that surrounds body tissues and maintains fluid balance. **III. Characteristics and Functions of Blood** - **Characteristics of Blood** - Blood is a viscous red fluid containing red blood cells, white blood cells, and platelets suspended in plasma. - Plasma constitutes 55% of blood volume; the remaining 45% is RBCs, WBCs, and platelets. - Blood has a slightly alkaline pH of 7.35-7.45. - The average adult blood volume is 5-6 liters. - **Functions of Blood** - Transports oxygen and nutrients to cells, waste products away from cells, and hormones from endocrine glands to tissues and cells. - Regulates acid-base balance with buffers. - Aids in the control of body temperature due to its high water content. - Controls the water content of cells based on sodium concentrations. - Protects the body against infection with leukocytes. - Prevents blood loss with the clotting mechanism. **IV. Red Blood Cells (Erythrocytes)** - **Components** - Contain cytoplasm and hemoglobin. - Hemoglobin carries oxygen from the lungs to the cells and carbon dioxide away from the cells to the lungs. - RBCs can be normochromic or hypochromic, macrocytic, normocytic, or microcytic. - The average lifespan of an RBC is 120 days. - Normal hemoglobin levels are 14-18 g/dL for men and 12-16 g/dL for women. - **Production** - Erythrocytes are continuously produced in the red bone marrow (vertebrae, ribs, sternum, proximal ends of the humerus, pelvic girdle, and femur). - Decreased oxygen delivery to tissues triggers the kidneys to release erythropoietin. - Erythropoietin initiates the development of mature RBCs in the bone marrow. - Increased RBCs allows more oxygen to be delivered to the tissues, shutting off the signal to increase RBC production. - Erythropoiesis is the process of RBC production. - Proper production depends on healthy bone, dietary substances (copper, essential amino acids), and certain vitamins (riboflavin, pyridoxine). - Production is stimulated by decreased oxygen levels and stops once oxygenation increases. - **Hematocrit** - Measures the volume percentage of red blood cells in whole blood. - Expressed as a percentage of the total blood volume. - Hemoglobin and hematocrit are based on whole blood and affected by plasma volume. - Hemoglobin and hematocrit often test high in patients suffering from dehydration. - Hemoglobin and hematocrit are low in patients suffering from fluid overload. - **Anemia** - Hemoglobin below normal is referred to as anemia. - Anemia results in less oxygen transported to cells, slower breakdown of nutrients, less energy produced, and decreased cellular function. - Patients with anemia feel \"tired\". **V. White Blood Cells (Leukocytes)** - **General Characteristics** - Have nuclei, are colorless, and live from a few days to several years. - Respond to symptoms of infection and recovery. - Conduct body defense against foreign invaders. - Help in revealing activity that points to hidden infection or may signal the intensity of chemotherapy. - Number 5,000-10,000 per mm3 of blood. - Some WBCs leave the bloodstream and move through tissue spaces to fight foreign invaders. - **Differential White Blood Cell Count** - A common blood test that counts and reports the five types of WBCs as percentages of the total examined. - **Categories of WBCs** - Granular (Granulocytes) - Agranular (Nongranulocytes) - **Granulocytes** - Include neutrophils, eosinophils, and basophils. - Function through phagocytosis (destroying and removing bacteria, cellular debris, and solid particles). - **Neutrophils** - Make up 60-70% of WBCs. - Ingest bacteria and dispose of dead tissue. - Mature neutrophils are called \"segs\" because their nuclei are segmented. - Release lysozymes to destroy bacteria. - Lifespan approximately 7 hours, with a 6-day supply constantly produced by the body. - Overwhelming infection can deplete marrow reserves. - Release of immature polymorphonuclear leukocytes (\"polys\") called bands when marrow reserves are depleted. - Bandemia is when the band count exceeds 8% of total polys, indicating a serious bacterial infection. - **Eosinophils** - Key in allergic responses. - Effective against certain parasitic worms. - Normal values are 1-4%. - **Basophils** - Key in non-specific immune responses and seen in allergic and inflammatory reactions. - Release histamine from granules when stimulated by an antigen or tissue injury. - Normal values are 0.5-1%. - **Agranulocytes** - **Monocytes** - Circulate in the bloodstream and work similarly to neutrophils. - Second responders at the scene of an injury. - Useful in removing dead bacteria and cells in the recovery state of acute bacterial infections. - Move into the tissue, engulfing foreign antigens and cell debris. - Normal values are 2-6%. - **Lymphocytes** - Form antibodies to combat foreign invaders or antigens. - Broken down into T cells and B cells. - **T cells**: migrate to the thymus, mature with thymic hormones, divide rapidly when exposed to an antigen, and produce sensitized T cells. - **B cells**: search out, identify, and bind with specific antigens, produce antibodies. - T cells and B cells work together to destroy the foreign antigen. - Normal values are 20-40%. **VI. Thrombocytes (Platelets)** - **Production and Function** - Produced in the red bone marrow. - Assist in clotting formation, sealing off breaks in blood vessel walls. - Lifespan is 5-9 days. - Normal value is 150,000-400,000 per mm3 of blood. - **Hemostasis** - Body process that stops the flow of blood and prevents hemorrhage. - Three actions take place: vessel spasm, platelet plug formation, and clot formation. - Process: Injury occurs, blood vessel is damaged, hemorrhage begins, platelets are activated and clump at the site of damage, thromboplastin is released, prothrombin is converted to thrombin, thrombin links with fibrinogen, fibrinogen forms fibrin, fibrin traps RBCs and platelets forming a clot, blood clot seals the damaged vessel. **VII. Blood Types and Rh Factor** - **Blood Types** - Determined by the presence or absence of specific antigens on the outer surface of RBCs. - ABO typing system: Type A, Type B, Type AB (universal recipient), Type O (universal donor). - **Rh Factor** - If present on the surface of RBCs, the person is Rh positive. - If absent, the person is Rh negative. - Receiving the wrong blood type can cause Rh antibodies to develop. **VIII. Lymphatic System** - **Overview** - Subdivision of the cardiovascular system, consisting of lymphatic vessels, lymph fluid, and lymph tissue. - Functions to maintain fluid balance, produce (mature) lymphocytes, and absorb and transport lipids from the intestine to the bloodstream. - **Lymph Fluid** - Similar in composition to plasma. - Flows through the lymphatic system by contraction of skeletal muscles. - Formed in tissue spaces and transported to eventually re-enter the circulatory system. - Excess fluid and protein molecules that cannot enter blood through capillary walls are returned as lymph. - Without lymph drainage, volume overload would occur in tissues. - Transported back to the bloodstream through lymphatic vessels; exchange occurs in capillary beds. - **Lymphatic Vessels** - Connect lymph nodes and collect lymph fluid. - Connected to the circulatory system for return of lymph fluid. - **Lymph Tissue** - **Lymph Nodes** (Glands): - Filter impurities from the lymph. - Produce lymphocytes (T cells and B cells). - Help fight infection. - Found in the axilla, abdomen, thorax, cervical, and inguinal regions. - The body contains 500-600 lymph nodes; most numerous in axilla, groin, abdomen, thorax, and cervical regions. - **Tonsils**: - Found in the mucous membranes of the pharynx. - Protect the body against invasion. - Produce lymphocytes and antibodies. - Trap bacteria and may become enlarged. - **Spleen**: - Located in the left upper quadrant. - Highly vascular, serves as a reservoir for blood, storing approximately 500 ml. - Matures lymphocytes, monocytes, and plasma cells (B cells). - Destroys old or imperfect red blood cells (hemolysis). - WBCs in the lining engulf and destroy foreign materials and damaged red blood cells. - Produces RBCs before birth. - **Thymus**: - Located between the lungs in the mediastinum. - Functions in utero and for several months after birth to develop the immune system. - Responsible for the development of T cells for the cell-mediated immune response. - Atrophies at puberty and is replaced by fat and connective tissue in adults. **IX. Diagnostic Tests** - **Complete Blood Count (CBC)** - Detects many disorders of the hematological system. - Provides data for the diagnosis and evaluation of disorders in other body systems. - Includes red and white cell counts, hematocrit and hemoglobin level, erythrocyte indices, differential white cell count, and examination of the peripheral blood cells. - **Erythrocyte Indices** (Red Cell Indexes) - Measurements of the size and hemoglobin content of erythrocytes. - Includes: - Mean corpuscular volume (MCV) -- average volume or size of a single RBC. - Mean corpuscular hemoglobin (MCH) -- average amount (weight) of hemoglobin within an RBC. - Mean corpuscular hemoglobin concentration (MCHC) -- average concentration or the percentage of hemoglobin within an RBC. - **Differential Count** - Actual cell count of leukocytes. - Identifies the number and percentage of individual types (neutrophils, basophils, eosinophils, monocytes, and macrophages). - Provides diagnostic information to the physician. - **Peripheral Smear** - Often accompanies the differential WBC count. - Permits examination of the size, shape, and structure of individual RBCs, WBCs, and platelets. - Most informative hematologic test when adequately prepared and examined microscopically by an experienced technologist. - **Schilling Test and Megaloblastic Anemia Profile** - Identifies the etiology of pernicious anemia (vitamin B12 deficiency). - May involve multiple stages of testing to determine if B12 intake is low or absorption is altered. - Measures absorption of radioactive vitamin B12, which is dependent on intrinsic factor produced by the gastric mucosa. - Patients with large resections of the stomach may not produce enough intrinsic factor to prevent pernicious anemia. - Measures the excretion of vitamin B12 after parenteral administration. - Normal findings: excretion of 8-40% of radioactive vitamin B12 within 24 hours. - Megaloblastic anemia profile (serum test) is replacing Schilling test; it measures vitamin B12, methylmalonic acid, and homocysteine levels. - **Gastric Analysis** - Evaluates the presence of intrinsic factor. - In pernicious anemia, gastric secretions are minimal and pH remains elevated after injection of histamine. - **Radiologic Studies** - Involve CT or MRI for evaluating the spleen, liver, or lymph nodes. - **Bone Marrow Aspiration or Biopsy** - Specific for establishing a diagnosis and for treatment response. - Used when a diagnosis is not clearly established by peripheral blood smears or when further information is needed. - Iliac crest most commonly used; sternum can also be used. - Bone marrow, being soft and semi-fluid, is removed by aspiration through a needle. - Most commonly performed in persons with marked anemia, neutropenia, acute leukemia, and thrombocytopenia. **X. Blood Transfusion Therapy** - **Reasons for Transfusions** - Replace blood volume due to major blood loss. - Packed RBCs, fresh frozen plasma, and platelets are used. - When given rapidly, can be used to control bleeding. - Not administered under pressure - Preserve oxygen-carrying capacity. - Increase coagulation capabilities. - **Types of Transfusion** - Donor blood. - Autologous. - **Religious Considerations** - Blood transfusion may not be acceptable. - If blood is not acceptable, plasma expanders may be used. - **Initiating a Blood Transfusion** - Before transfusion: type and crossmatch to prevent fatal reactions. - Follow facility protocols for labeling. - Informed consent must be obtained. - Ensure patient has IV access (preferably 18-gauge or larger, 20-gauge minimum). - Monitor vital signs before transfusion and at regular intervals throughout and after the procedure. - Transfusion reactions can occur at any time, typically within the first 15 minutes. - **Coordinated Care** - Care of the patient receiving a blood transfusion is the nurse\'s responsibility. - Requires critical thinking skills and knowledge. - LPN/LVN scope of practice is variable by state. - UAP may be delegated to monitor vital signs, collect equipment, and provide patient comfort measures. - Nurse responsibilities: donor/recipient identification, infusing the unit within required time (2 to 4 hours from start to completion), and monitoring patient outcomes. - **Steps for Transfusion of Blood or Blood Products** - Prime tubing with normal saline (do not use dextrose). - Use Y tubing with a blood filter. - Completely fill with saline solution. - Saline in the filter prevents debris buildup. - Attach transfusion tubing to the patient\'s intravenous access. - Inspect the blood or blood product bag for signs of leakage or unusual appearance. - Report immediately and return blood to the laboratory or blood bank as this may indicate contamination. - Remain with the patient for the first 15 to 20 minutes of the transfusion. - Start the transfusion slowly. - Monitor vital signs frequently. - Address any complaints of discomfort immediately. - At completion of the blood transfusion, flush IV tubing with normal saline. - Use a new tubing set if another unit is ordered. - **Blood Transfusion Reactions** - If blood is incompatible with patient, can cause a reaction, this is an EMERGENCY. - **Indicators of a Transfusion Reaction** - "Not feeling right". - Sense of impending doom. - Chills. - Fever. - Low back pain. - Pruritus. - Hypotension. - Nausea/vomiting. - Decreased urine output. - Chest pain. - Wheezing. - Dyspnea. - If a transfusion reaction is suspected, stop the transfusion immediately. - Keep the vein open with normal saline. - Notify the healthcare provider and blood bank. - Document on an incident report. - May need to collect urine specimens. - Monitor vital signs every 15 minutes. - Reassure and support the patient and family. - **Types of Blood Transfusion Reactions** - Hemolytic. - Nonhemolytic. - Allergic. - Anaphylactic. - **Complications of Reaction** - **Circulatory Overload** - The patient is unable to handle the additional fluid. - **Clinical manifestations**: cough, frothy sputum, cyanosis, hypotension.