EFREN N. AQUINO M.D. Aug. 4, 2009

1. Care of the Patient with a Blood or Lymphatic Disorder – Part 1 EFREN N. AQUINO M.D. Aug. 4, 2009

2. Overview of Anatomy and Physiology • We live in a hostile and dangerous environment. Each day we are faced with potentially harmful toxins, disease-causing bacteria, viruses, and even cells from our own bodies that have been transformed into cancerous invaders. Fortunately, we are protected from this staggering variety of biologic enemies by a remarkable set of defense mechanisms. • These mechanisms involve the circulatory and lymphatic system

3. Overview of Anatomy and Physiology Characteristics of blood • Consistency • 45% blood cells • 55% blood plasma** • pH • 7.35-7.45 • Volume • 10-12 pints = 5 – 6 Liters

4. The blood performs three critical functions. • First: transports oxygen and nutrition to the cells and waste products away from the cells, and transports hormones from endocrine glands to tissues and cells. • Second: regulates the acid-base balance (pH) with buffers, aids with body temperature because of its water contents, and controls the water content of its cells as a result of dissolved sodium ions. • Third: it protects the body against infection with special cells and prevents blood loss with special clotting mechanisms.

5. Red blood cells (RBC) • Erythrocytes • Continuously produced in the red bone marrow ** • Transport oxygen and carbon dioxide White blood cells (WBC) • Leukocytes • Body defenses: destruction of bacteria and viruses called phagocytosis Thrombocytes (platelets) • Initiate blood clotting

6. Red Blood Cells • Erythrocytes (red blood cells [RBCs]) give blood its rich color. • A mature RBC contains cytoplasm and the red pigment hemoglobin (Hgb), a compound in the blood that carries oxygen to the cells from the lungs. • The normal hemoglobin level is • 14 to 18 g/dL for men and • 12 to 16 g/dL for women. • The average life span of an RBC is 120 days.

7. Red Blood Cells, cont.. • An erythrocyte is the major cellular element of the circulating blood; its principal function is to transport oxygen and carbon dioxide. • Erythrocytes are continuously produced in the red bone marrow, principally in the vertebrae, ribs, sternum, and proximal ends of the humerus and femur. (all bones with red bone marrow..ena)

8. Red Blood Cells, cont.. • Erythropoiesis (the process of RBC production) depends on several factors, among them health conditions of the bone marrow; dietary substances such as iron and copper, plus essential amino acids and certain vitamins like vitamin B12 folic acid, riboflavin (vitamin B2), and pyridoxine (vitamin B6). • A feedback mechanism is energized when the amount of oxygen delivered to the tissues by RBCs is decreased.

9. Red Blood Cells, cont.. • The decreased oxygen triggers the release of an enzyme, the renal erythropoietic factor, in the kidneys. Erythropoietin is carried to the bone marrow, where it initiates the development of mature RBCs. The increased number of RBCs allows more oxygen to be delivered to the tissues, and as a result, the signal to increase RBC production is shut off.

10. Red Blood Cells, cont.. • A common laboratory test called the hematocrit which is a measure of the packed cell volume of red blood cells, expressed as a percentage of the total blood volume • Normally about 42% to 52% of the blood volume in men and 37% to 47% in women consists of RBCs.

11. Red Blood Cells, cont.. • Hemoglobin is another lab exam which represents the oxygen carrying capacity of the RBC. • If hemoglobin falls below the normal level, as it does in anemia, an unhealthy chain reaction begins: less hemoglobin, less oxygen transported to cells, slower breakdown and use of nutrients by cells, less energy produced by cells, decreased cellular function. If one understands the relationship between hemoglobin and energy, one can understand that an anemic person’s complaint will be of feeling “tired all the time”.

12. White Blood Cells • Unlike erythrocytes, leukocytes (white blood cells [WBCs]) have nuclei, are colorless, and live from a few days to several years. • They are primarily involved in body defenses, such as destruction of bacteria and viruses. • They number 5000 to 10,000 per mm3 of blood. • Some WBCs can actually leave the bloodstream and move through tissue spaces to fight foreign invaders, such as bacteria.

13. White Blood Cells, cont.. There are two broad categories of white cells: • granulocytes and • nongranulocytes. The three types of granulocytes are: • neutrophils, • eosinophils, and • basophils. The nongranulocytes include: • lymphocutes and • monocytes.

14. White Blood Cells, cont.. • A differential white blood cell count is an examination in which the different kind of WBCs are counted and reported as percentages of the total examined. • Neutrophils are the primary phagocytic cells involved in acute inflammatory response. A mature neutrophil is called a segmental neutrophil or “seg” because the nucleus is segmented into two to five lobes connected by strands. They also release lysozyme, an enzyme that destroys certain bacteria. • Normal value: 60-70%

15. White Blood Cells, cont.. • Neutrophils: Because neutrophils respond in proportion to the severity of the infection, an overwhelming infection may deplete marrow reserves. When this happens, the marrow releases immature polymorphonuclear leukocytes (“polys”), called bands, which are immature neutrophils that are in the final stages of development. • When the band count exceeds 8% of the total number of WBC’s, the marrow has used up its reserve. The presence of excess bands in the peripheral bloods is called a shift to the left (i.e., a shift toward immature cells) and indicates severe infection.

16. Eosinophils are WBCs that play a role in allergic reactions and are effective against certain parasitic worms. Normal value = 1- 4 % Basophils are WBCs that are essential to the nonspecific immune response to inflammation because of their role in releasing histamine (vasodilator) during tissue damage or invasion. Basophils have cytoplasmic granules that contain heparin, serotonin, and histamine, If a basophil is stimulated by an antigen or by tissue injury, it will respond by releasing substances within the granules. This is part of the response seen in allergic and inflammatory reactions. Normal value of basophils are 0.5% to 1%.

17. Monocytes are WBCs that function similarly to neutrophils; they circulate in the bloodstream and move into tissue, where they engulf foreign antigens and cell debris. Monocytes are the second type of WBC to arrive at the scene of an injury. They are useful in removing dead bacterial infections. Normal values of monocytes are 2% to 6%.

18. The lymphocytes are WBCs that are responsible for antibody formation, a special protein that combats foreign invaders, or antigens. They set up the antigen-antibody process, which protects the body. • There are two groups of lymphocytes: B cells and T cells. The function of the B cells is to search out, identify, and bind with specific antigens. T cells, when exposed to an antigen, divide rapidly and produce large numbers of new T cells that are sensitized to that antigen. They work together with the B cells to destroy the foreign antigen. Normal values of lymphocytes are 20% to 40%.

20. RBC with Hemoglobin / Hematodrit

21. Normal WBC results done with differential count Total white cell count 5,000-10,000/mm3 • Neutrophils 60 - 70%. • Lymphocytes 20 - 40%. • Monocytes 2 - 6%. • Eosinophils 1- 4%. • Basophils 0.5 - 1%. • Bands 0 - 3%.

23. Thrombocytes, or platelets, are the smallest cells in the blood. They are circular cell fragments, which do not contain nuclei. They have a life span of 5 to 9 days and number 150,000 to 400,000 per mm3 of blood. They are produced in the red bone marrow and function in the process of hemostasis (the prevention of blood loss). They assist in clotting formation, which seals off a break in the continuity of the walls of the blood vessels.

24. Human blood cells. (Thibodeau, G.A., Patton, K.T. [2003]. Anatomy and physiology. [5th ed.]. St. Louis: Mosby.)

26. Hemostasis:A body process that arrests the flow of blood and prevents hemorrhage by the following actions: • Vessel spasm • Platelet plug formation and • Clot formation

27. Hemostasis: • Injury • Hemorrhage • Grouping platelets • Thromboplastin released • Converts prothrombin to thrombin • Links with fibrinogen • Formation of fibrin • Trap RBCs and platelets • Forms clot

28. Figure 7-2 Blood clotting.

29. Blood types (groups) • Determined by the presence or absence of specific antigens on the outer surface of the RBC • Type A • Type B • Type AB • Universal recipient • Type O • Universal donor

31. Rh factor • Rh antibodies may be located on the surface of the RBC • Rh positive: antibodies are present • Rh negative: antibodies are not present Erythroblastosis Fetalis

33. Erythroblastosis fetalis is hemolytic anemia in the fetus or neonate caused by transplacental transmission of maternal antibodies to fetal RBCs. • Erythroblastosis fetalis classically results from Rh0(D) incompatibility, which may develop when a woman with Rh-negative blood is impregnated by a man with Rh-positive blood and conceives a fetus with Rh-positive blood. • Also known as Hemolytic disease of the fetus and newborn, HDN, HDFN.

34. Lymphatic system The lymphatic system is a subdivision of the cardiovascular system. It consists of lymphatic vessels, the lymph fluid, and the lymph tissue. Functions • Maintenance of fluid balance • Production of lymphocytes • Absorption and transportation of lipids from the intestine to the bloodstream

35. Lymphatic system • Lymph and lymph vessels • Lymph is a specialized fluid formed in the tissue spaces transported by way of the lymphatic vessels and reenters the circulatory system • Lymphatic tissues • Lymph nodes • Tonsils • Spleen • Thymus

36. Lymphatic tissues • Lymph nodes • Act as filters, keeping particulate matter such as bacteria from entering bloodstream • Produce lymphocytes • Tonsils • Produce lymphocytes and antibodies: trap bacteria

37. Lymphatic tissue (continued) • Spleen • Reservoir for blood; Stores about 500 ml of blood that can be released in emergencies**; forms lymphocytes, monocytes, and plasma; destroys worn-out RBCs; removes bacteria by phagocytosis • Thymus • Immune system before and a few months after birth; atrophies at puberty

38. Principal organs of the lymphatic system. (From Thibodeau, G.A., Patton, K.T. [2003]. Anatomy and physiology. [5th ed.]. St. Louis: Mosby.)

39. Disorders of the Hematological and Lymphatic Systems • Diagnostic tests • Complete blood count (CBC) • Red cell indices • Peripheral smear • Schilling test: pernicious anemia** • Megaloblastic anemia profile • Lymphangiography • Bone marrow aspiration or biopsy

40. Diagnostic tests Complete blood count (CBC) • The complete blood count (CBC) is an important part of routine screening and hospital admission. It involves several tests, each of which assesses the three major cells formed in the bone marrow. • A CBC includes red and white cell counts, hematocrit and hemoglobin levels, erythrocyte indices, differential white cell count, and examination of the peripheral blood cells

41. Red Cell Indices: Erythrocyte indices are measurements of the size and hemoglobin content of red blood cells. Mean Corpuscular volume (MCV). Mean corpuscular hemoglobin (MCH) Mean corpuscular hemoglobin concentration (MCHC)

42. Peripheral Smear • A peripheral smear often accompanies the differential WBC count and permits examination of the size, shape, and structure of individual RBCs and platelets. All three hematological cell lines (RBCs, WBCs, platelets) can be examined. When adequately prepared and examined microscopically by an experienced technologist, a smear of peripheral blood is the most informative of all hematological tests.

43. Schilling Test and Megaloblastic Anemia Profile • The Schilling test is a laboratory blood test for diagnosing pernicious anemia. The test measures the absorption of radioactive vitamin B12, before and after parenteral injection of the intrinsic factor, by examination of the urinary excretion of vitamin B12. • Normal findings are excretion of 8% to 40% of radioactive vitamin B12 within 24 hours.

44. Gastric Analysis • Gastric analysis is an older test in determining pernicious anemia. In pernicious anemia the gastric secretions are minimal and the pH remains elevated, even after injection of histamine.

45. Radiologic Studies • Radiologic studies for the hematological system involve primarily the use of computed tomography (CT) or magnetic resonance imaging (MRI) for evaluating the spleen, liver, and lymph nodes. In the past, lymphangiography with the use of contrast dye was a common procedure to evaluate deep lymph nodes. CT is now the preferred method (Lewis et al, 2004).

46. Bone Marrow Aspiration or Biopsy • When the diagnosis is not clearly established by peripheral blood smears or when further information is needed, bone marrow aspiration or biopsy is specific for establishing the dianosis and for treatment response. • The most common site for this procedure is the posterior iliac crest, although the sternum can also be used; however, the sternum is generally used only for aspiration.

47. Bone Marrow Aspiration or Biopsy • Bone marrow aspiration is most commonly performed in people with marked anemia, neutropenia, acute leukemia, and thrombocytopenia. • Although complications of bone marrow aspiration are minimal, there is a possibility of penetrating the bone and underlying structures. This hazard is greatest in aspiration procedure involving the sternum.

48. Lymphangiography • Lymphangiography is a radiologic examination used to detect metastatic involvement of the lymph nodes. Contrast medium is injected into a lymphatic vessel of the foot or hand, followed by radiological visualization of the lymphatic system. • This examination is being replaced by CT scanning.

49. Disorders of the Hematological and Lymphatic Systems Anemia • Definition • Disorder characterized by RBC and hemoglobin and hematocrit levels below normal range • Causes delivery of insufficient amounts of oxygen to tissues and cells

50. Normal values • Hemoglobin = 14 – 18 gm/dl** • Hematocrit = 40 – 52 %