CBC Complete Blood Count

What is CBC? Commonly ordered blood test Calculation of the formed elements of blood RBC Count RBC Indices Hemoglobin Hematocrit WBC Count WBC Differential Platelet Count

CBC Collection Tube Purple top tube Anti-coagulant additive Mix 5-10 times

Why are CBCs needed? Screening during a general physical examination Especially on admission to a health care facility or before surgery

Red Blood Cells (RBC) Normal Values Males: 4.7-6.1 million/mm3 Females: 4.0-5.0 million/mm3

RBC Determines RBC/mm3 Contains hemoglobin which is responsible for the transport of oxygen and carbon dioxide Increased RBC occurs in polychythmia vera Decreased RBC occurs in anemia Congenital heart disease and events that induce chronic hypoxia Moving to a high altitude or lung disease

Red Blood Cell Indices Red blood cell indices provide information about the mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), and Red blood cell distribution width (RDW) Normal Values: MCV: 85-95fL MCH:28-32pg/cell MCHC:33-35g/dL RDW:11.6-14.8

Results Increased in… MCV: Alcoholism, Antimetabolite therapy, liver disease, pernicious anemia, Vit. B12 anemia MCH: Macrocytic anemias MCHC: Thalassemia, Spherocytosis RDW: Anemias with heterogeneous cell size

Results Decreased in… MCV: Iron-deficiency anemia, Thalassemias MCH: Hypochromic anemias, Microcytic anemias MCHC: Iron deficiency anemia RDW: N/A

Nursing Interventions Assist in the diagnosis of anemia Detect a hematologic disorder, neoplasm, or immunologic abnormality Determine the presence of a hereditary hematologic abnormality Monitor the progression of nonhematologic disorders such as COPD, cancer, and renal disease Monitor the response to drugs or chemotherapy, and evaluate undesired reactions to drugs that may cause blood dyscrasias

Hemoglobin Carries O2 and removes CO2 Buffer for acid-base balance in extracellular fluid Levels used with Hematocrit to evaluate anemia Normal ranges Males: 13.2-17.3 g/dL Females: 11.7-15.5 g/dL

Critical Values Less than 6.0 g/dL More than 18.0 g/dL High Hgb Polychythmia Low Hgb Anemia

Results Burns CHF COPD Dehydration Erythrocytosis Anemia Carcinoma Increased in… Decreased in… Burns CHF COPD Dehydration Erythrocytosis Anemia Carcinoma Fluid retention Incompatible blood transfusion Hodgkin’s disease Pregnancy

Nursing Interventions Monitor fluid imbalances Monitor response to drugs or chemotherapy and evaluate undesired reactions to drugs Screening as part of CBC

Hematocrit Measures the amount of red blood cells (RBC) in the blood Expressed as a fraction or percentage Increases when RBC number increases or plasma level drops Decreases due to RBC production decrease, blood loss or RBC destruction

Normal Values Age Hematocrit (%) Cord Blood 47-57 1 Day Old 51-65 2 Weeks Old 1 Month Old 38-52 6 Months Old 35-41 1 Year Old 37-41 10 Years Old 36-42 Adult Male 43-49 Adult Female 38-44

Abnormal Values Burns CHF COPD Dehydration Erythrocytosis Increase Decrease Burns CHF COPD Dehydration Erythrocytosis Hemoconcentration High Altitudes Polycythemia Shock Anemia Blood Loss Bone Marrow Hyperplasia Chronic Disease Hemolytic Disorders Hemorrhage Fluid Retention Nutritional Deficit Pregnancy

White Blood Cells (WBC) Normal Ranges: (adults) 5000-10,000/mm3 Critical Values >30,000/mm 3 <2500mm3 WBCs constitute the body’s primary defense system against foreign organisms, and tissues Life span = 13 to 20 days Old WBCs are destroyed by the lymphatic system and excreted in feces White “knobby” things = WBC

Nursing Interventions Assist in determining the cause of an elevated WBC (e.g. infection, inflammatory process) Monitor the progression of nonhematologic disorders (e.g. chronic obstructive pulmonary disease, malaborption syndrome, cancer, renal disease) Monitor the response to medication (e.g. chemotherapy)

An increase in WBCs = Leukocytosis Pathologic Conditions: Transfusion reactions All types of infections Anemia Appendicitis Cushing’s disease Inflammatory disorders Leukemia Physiological and environmental conditions: Emotional stress Exposure to cold Menstruation Pregnancy and labor Strenuous exercise

A decrease in WBCs = Leukopenia Physiological conditions: Diurnal rhythms Pathologic Conditions: Alcoholism Anemia Bone marrow depression Malnutrition Radiation Viral infections

White Blood Cell Count and Cell Differential WBC’s constitute the bodies primary defence system Normal life span is 13 to 20 days; old cells are destroyed by lymphatic system and excreted Produced in the bone marrow

Differential WBC Count The WBC’s in the count and differential are reported as an absolute value, as a percent or as SI Units using a base cell count of 100 cells, the relative percentages are counted Absolute value is obtained by multiplying the percentage by the total count Contains K3 or K2 EDTA (Ethylenediaminetetracetic Acid), the chemical of choice to prevent sample clotting; binds to Ca and prevents the activation of clotting

Neutrophils Defend against bacteria and fungal infection; first response Activity and large numbers formulate pus Normal Values: 50-70% or 1.8-7.7 ↑Neutrophilia—acute hemolysis, hemorrhage, extremes in temperature, infection, inflammatory conditions ↓ Neutropenia—acromegaly, Addison’s disease, anaphylaxis, starvation, bone marrow depression,

Lymphocytes A cell of the lymphatic system that participates in the immune response 3 Types B Cells: make antibodies that bind to pathogens; retain memory T Cells: immune response coordination Natural Killer Cells: kill the cells of the body which display signal Normal Values: 20-30% or 1.0-4.8 ↑ Lymphocytosis—Addison’s disease, Infections, Lymphocytotic Leukemia, Lymphomas, Myeloma, Rickets, Ulcerative Colitis ↓ Lymphopenia—AIDS, Burns, Newborn Hemolytic Disease, Immunodeficiency, Malnutrition, Pneumonia, Radiation, Septicemia, Transfusion Reaction

Monocytes Present pieces of pathogens to T-Cells so that pathogens can be recognized to mount antibody response; long living Leave the blood stream to become tissue macrophages to remove dead cell debris and attack microorganisms Normal Values: 2-8% or 0-0.8 ↑ Monocytosis—Carcinomas, Hemolytic Anemia, Hodgkin’s Disease, Infections, Lymphomas, Monocytotic Leukemia ↓ Monocytopneia—Aplastic Anemia, Corticosteroid Therapy (Prednisone)

Eosiniphils Primary deal with parasitic infections Inflammatory cells in allergic reactions Normal Values: 2-4% or 0-0.45 ↑ Eosinophilia—Allergies, Parasitic Infection, Autoimmune Disorders, Asthma ↓ Eosinopenia—Steroid Therapy

Basophils Responsible for allergic and antigen response by releasing histamine causing inflammation Inflammatory cells in allergic reactions Normal Values: 0.5%-1% or 0-0.2 ↑ Basophilia—Inflammatory processes during healing ↓ Basopenia—Hypersensitivity reactions and corticosteroid therapy

Platelets Small disk-like shaped fragments of cells Formed in the red bone marrow and circulate freely in blood in an inactive state When injury occurs, platelets collect at a site and are activated Substances released from the platelet granules activate coagulation factors in the blood plasma and initiate the formation of a stable clot composed of fibrin

Platelets Platelet counts are done to establish the patients coagulation abilities Normal Values Adults: 150 000 - 400 000/ mm3 of blood Abnormal Values Increased Values Decreased Values Results in increased coagulation of blood Results in decreased coagulation of blood

Nursing Interventions Coagulation System Tests Evaluate Bleeding Time Amount of time for bleeding to stop after a small incision is made in the skin Normal bleeding time: 3-7 minutes Prolongation occurs in patients with decreased platelet count, anti-coagulation therapy, ASA ingestion, leukemia, or clotting factor deficiencies

Nursing Interventions Coagulation System Tests Evaluate Factors Assay Measures the hemostatic activity Decreased activity of the coagulation factors will result in defective clot formation

Nursing Interventions Patients With Increased Platelet Count Monitor patients for risk of vascular thrombosis or pulmonary emboli Administer anti-coagulation therapy Encourage healthy diet and exercise

Nursing Interventions Patients With Decreased Platelet Count Monitor patients for risk of spontaneous bleeding Patient teaching

Interfering Factors Failure to fill tube Hemolyzed or clotted specimens Recent transfusion history

Nursing Implications for CBC If lab is performing, make sure they are aware of any latex allergies Keep patient calm Ensure they breathe normally Avoid any movement Ensure prompt transportation of specimen to the lab

Case Study 1 Your patient is post-op day 1. She had a total knee replacement. You notice that the site is bleeding, inflamed and reddened upon your morning assessment. You call the doctor and he says to obtain a complete blood count and that he will be in tomorrow. You get it back later that day. What would you expect the results to be and why?

Answers RBC will  due to loss of blood 3.8 x 106 cells/mm3 Hematocrit and hemoglobin levels  due to loss of blood Hemoglobin: 7g/dL Hematocrit: 20% WBC will be  due to risk for infection 11 000 mm3 Platelets will  due to inc bleeding and inability to clot 140 000/mm3