HEMA LAB: INTRODUCTION

What is Hematology?

Hematology is defined as the study of blood, its development, and diseases associated with it

What does Hematology include?

 It includes the study of RBCs (erythrocytes), WBCs (leukocytes), platelets (thrombocytes), and hemostatic elements in plasma in order to provide a differential diagnosis

What are the Functions of the blood?

Respiratory; Homeostasis; Nutritive; Excretory; Immunity; Water Regulation; Transportation of Hormones; Hemostasis

What is the Respiratory function of blood?

 refers to the delivery of gases to and from the tissues

What happens to Oxygen in the Respiratory function of blood?

 Oxygen attach to hemoglobin in RBCs for delivery from the lungs to the peripheral tissues.

What happens to Carbon dioxide in the Respiratory function of blood?

 Carbon dioxide is also transported by the blood from the tissues for elimination by the lungs

What is the Homeostasis function of blood?

 refers to the regulation of certain balances in the body.

What homeostatic mechanisms involve the blood?

The blood is involved in a number of certain homeostatic mechanisms such as pH homeostasis and temperature regulation

What is the Nutritive function of blood?

refers to the delivery of nutrients to the tissues. These nutrients are dissolved in the plasma.

What is the Excretory function of blood?

refers to the delivery of waste products from the tissues to the excretory organs for elimination from the body.

What is an example of waste products transported in the Excretory function of blood?

Non-protein nitrogenous wastes (NPNs) such as urea and creatinine are dissolved in plasma and filtered by the kidneys

What is the Immunity function of blood?

 refers to the body’s defense against infectious organisms (Bacteria, Fungi, Parasites, or Viruses)

What role do White blood cells populations in the blood play in immunity?

White blood cells populations in the blood are play a protective role against a group of microorganisms

How do Neutrophils protect the body?

Neutrophils protect against most bacterial agents by engulfing these bacteria, and releasing its granular contents, which have anti-bacterial action

How do Monocytes protect the body?

Monocytes protect against a wide range of infectious agents by performing phagocytosis

What do Eosinophils protect against?

Eosinophils protect against helminthic infections

What is the Water Regulation function of blood?

 the blood is involved in maintaining the water levels in the body.

How is water excreted or reabsorbed into the blood?

Water is excreted or reabsorbed into the blood as a function of plasma osmolality, which is the measure of solute concentration of the blood.

What does Increased plasma osmolality promote?

Increased plasma osmolality promotes water reabsorption in the kidneys.

What does Decreased plasma osmolality promote?

 Decreased plasma osmolality promotes water excretion.

What is the Transportation of Hormones function of blood?

Hormones are secreted by endocrine glands. The targets of endocrine hormones are distant from its source. Thus, the hormones need to be dissolved in the plasma to reach its target tissue/organ

Where are Hormones secreted from?

Hormones are secreted by endocrine glands.

Why do hormones need to be dissolved in plasma?

The targets of endocrine hormones are distant from its source. Thus, the hormones need to be dissolved in the plasma to reach its target tissue/organ.

What is the Hemostasis function of blood?

refers to the mechanism by which blood flow to an injured blood vessel is arrested in order to prevent excessive blood loss.

What is the role of platelets and hemostatic elements in plasma in Hemostasis?

This occurs as a function of platelets (forming a platelet plug) and hemostatic elements in plasma (responsible for clot formation and dissolution).

What are Common Hematological Tests?

Complete Blood Count (CBC); Peripheral Blood Smear (PBS) Examination; Bleeding Time and Coagulation Tests; Reticulocyte Count; Erythrocyte Sedimentation Rate (ESR)

What is a Complete Blood Count (CBC)?

Composed of a panel of tests to evaluate the formed elements in the blood

What do CBC results offer?

the CBC results offer a wealth of information regarding the health status of an individual

What is the significance of each component of CBC?

each component of CBC is associated with different conditions (similar to the components of urinalysis)

What are the Components of CBC?

Cell counts (RBC count, WBC count, Platelet count); Hemoglobin determination; Hematocrit testing; WBC differential count; RBC indices

What are Cell counts in CBC?

Cell counts (RBC count, WBC count, Platelet count) – determines the quantities of circulating blood cells

What can increases or decreases in each of the cell counts reveal?

 increases or decreases in each of the cell counts may reveal the presence of a disease process

What is Hemoglobin determination?

quantitative measure of hemoglobin, the protein in RBCs responsible for binding oxygen

What can Low levels of hemoglobin cause?

Low levels of hemoglobin impair oxygen delivery to the tissues and are most often associated with anemia

What is Hematocrit testing?

determination of the amount of red blood cells in whole blood (expressed as a relative quantity; ratio of red blood cells to whole blood in a sample)

What is WBC differential count?

details the relative counts of each white blood cell population (Neutrophils, Lymphocytes, Monocytes, Eosinophils, and Basophils) - each WBC population is expressed as the percentage of white blood cells

What are RBC indices?

values of these indices aid in making a specific diagnosis of anemia

What is Mean Cell/Corpuscular Volume (MCV)?

average volume of red blood cells in a sample

What is Mean Cell/Corpuscular Hemoglobin (MCH)?

average amount of hemoglobin in each red blood cell in a sample

What is Mean Cell/Corpuscular Hemoglobin Concentration (MCHC)?

average hemoglobin content for a specified volume of red blood cells

What is Reticulocyte Distribution Width (RDW)?

quantitates the spread of RBC sizes in a sample.

What does a greater RDW indicate?

The greater the RDW, the greater is the difference in RBC sizes in the sample.

What is Peripheral Blood Smear (PBS) Examination?

performed to analyze the morphologic characteristics of RBCs, WBCs, and Platelets

What may abnormal morphologic characteristics indicate?

abnormal morphologic characteristics may indicate the presence of disease processes

What is an example of an abnormal morphologic characteristic in PBS Examination?

 the presence of agranular platelets may be associated with Gray Platelet Syndrome, which also affects platelet function

What are Bleeding Time and Coagulation Tests?

these are tests used to evaluate hemostatic functions of the blood:

What is Bleeding Time?

general screening test for hemostatic abnormalities

What is Prothrombin Time?

coagulation test used to evaluate the extrinsic pathway

What is (Activated) Partial Thromboplastin Time?

coagulation test used to evaluate the intrinsic pathway

What are Thrombin Time and Reptilase Time?

coagulation tests used to evaluate the Fibrinogen function

What is Stypven Time / Dilute Russel Viper Venom Time?

coagulation test used to evaluate the common pathway

What is Reticulocyte Count?

Reticulocytes are immature red blood cells. These are normally found in the blood in small numbers

What are Reticulocytes?

Reticulocytes are immature red blood cells.

Where are Reticulocytes normally found?

These are normally found in the blood in small numbers

What does Evaluation of reticulocyte count reveal?

Evaluation of its count reveals the bone marrow’s response to hypoxia

What is Erythrocyte Sedimentation Rate (ESR)?

This test is a measure of the rate of fall of red blood cells within a packed column

What was ESR traditionally used for?

Traditionally, this test was used as a screening test for the presence of inflammatory processes

What are the Physical Characteristics of Blood?

Fluid in vivo; Volume: 4-6 L (normal adult volume) or 75-85 mL per kilogram of body weight; Viscosity: Viscous (3.5-4.5 times thicker than water); Reaction: slightly alkaline; Arterial blood pH: 7.35 - 7.45; Venous blood pH: 7.38 - 7.48; Osmolality: 280-295 mOsm/kg; Average specific gravity: 1.055

What is the physical state of blood in vivo?

Fluid in vivo (due to balance between proclotting factors and anticoagulants)

What is the normal adult volume of blood?

Volume: 4-6 L (normal adult volume) or 75-85 mL per kilogram of body weight

What is the viscosity of blood?

 Viscosity: Viscous (3.5-4.5 times thicker than water)

What is the Arterial blood pH?

What is the Arterial blood pH?

What is the reaction of blood?

Reaction: slightly alkaline

What is the Venous blood pH?

Venous blood pH: 7.38 - 7.48

What is the Osmolality of blood?

Osmolality: 280-295 mOsm/kg

What is the Average specific gravity of blood?

Average specific gravity: 1.055

What are the components of blood?

Cellular Components (Formed Elements); Liquid Component (called Plasma or Serum)

What are the Cellular Components (Formed Elements) of blood?

Red Blood Cells (Erythrocytes); White Blood Cells (Leukocytes); Platelets (Thrombocytes)

What are Red Blood Cells?

Red Blood Cells (Erythrocytes)

What are White Blood Cells?

White Blood Cells (Leukocytes)

What are Platelets?

Platelets (Thrombocytes)

What is the Liquid Component of blood?

Liquid Component (called Plasma or Serum)

What is the Plasma or Serum composed mostly of?

composed mostly of water

What dissolved elements are found in Plasma or Serum?

dissolved elements include carbohydrates, proteins, lipids, non-protein nitrogenous compounds (NPNs), vitamins, electrolytes, trace elements, hormones, and gases.

What is Plasma?

 Liquid part of anticoagulated and unclotted blood

What is Serum?

Liquid part of clotted blood

What is the appearance of Plasma?

Hazy

What is the appearance of Serum?

Clearer

What coagulation factors are present in Fresh Plasma?

All Coagulation Factors are present (Fresh Plasma): FI, FII, FV, FVII, FVIII:c, FIX, FX, FXI, FXII, FXIII, PK, HMWK

What Clotting Factors are consumed in Coagulation?

FI / I (Fibrinogen); FV / V (Proaccelerin); FVIII:c / VIII:c (Anti-Hemophilic Factor A); FXIII / XIII (Fibrin Stabilizing Factor)

What is FI / I?

 Fibrinogen

What is FV / V?

Proaccelerin

What is FVIII:c / VIII:c?

Anti-Hemophilic Factor A

What is FXIII / XIII?

Fibrin Stabilizing Factor

How much FII / II (Prothtrombin) is present in Serum?

Only residual amount (less than 20%) of FII / II (Prothtrombin) is present

What does *F stand for?

Factor

How are the clotting factors named?

The clotting factors are named as Roman numerals