Chapter 17 - Collecting, processing, and testing blood specimens. In many health-care settings, the medical assistant is responsible for collecting blood specimens from patients and even performs some testing in the waived category. In order to properly collect the specimens, you will need to review the circulatory system and the function of blood. You will be introduced in this chapter to venipuncture and capillary collection procedures, and you will learn the appropriate supplies and equipment needed to perform these procedures.
CHAPTER 17 Collecting, Processing, and Testing Blood Specimens © 2011 The McGraw-Hill Companies, Inc All rights reserved 172 Learning Outcomes 17.1 Discuss the composition and function of blood 17.2 Describe the process for collecting a blood specimen 17.3 Explain the importance of confirming patients’ identities and correctly identifying blood samples 17.4 Describe how to perform venipuncture and capillary puncture procedures © 2011 The McGraw-Hill Companies, Inc All rights reserved 173 Learning Outcomes (cont.) 17.5 Identify the equipment and supplies required for blood-drawing procedures 17.6 Discuss the correct procedures for disposing of waste generated during blood-drawing procedures 17.7 Discuss common fears and concerns of patients and how to ease these fears © 2011 The McGraw-Hill Companies, Inc All rights reserved 174 Learning Outcomes (cont.) 17.8 Develop techniques for helping patients with special needs, including children, the elderly, patients at risk for uncontrolled bleeding, and difficult patients 17.9 Identify common blood tests and explain their purposes 17.10Perform certain blood tests © 2011 The McGraw-Hill Companies, Inc All rights reserved 175 Introduction • Medical assistant – Collects blood specimens – Performs waived testing – Knowledge needed • Understand circulatory system and function of blood • Appropriate supplies and equipment • How to perform and screen common blood tests © 2011 The McGraw-Hill Companies, Inc All rights reserved 176 Role of the Medical Assistant • Phlebotomy – insertion of a needle or cannula into a vein to withdraw blood • Put the patient at ease during procedure • Process specimens and conduct testing • Complete necessary paperwork and make sure specimens are handled properly © 2011 The McGraw-Hill Companies, Inc All rights reserved 177 Functions and Composition of Blood • Circulatory system transports blood – Heart pumps 8–12 pints of blood through 70,000 miles of vessels/day • Hematology – the study of blood © 2011 The McGraw-Hill Companies, Inc All rights reserved 178 Functions and Composition of Blood (cont.) • Functions of blood – Distributes oxygen, nutrients, and hormones – Eliminates waste products – Attacks infecting pathogens – Maintains acid-base balance – Regulates body temperature © 2011 The McGraw-Hill Companies, Inc All rights reserved 179 Functions and Composition of Blood (cont.) • Red blood cells – erythrocytes – Internal respiration – Transport oxygen to cells • Hemoglobin – 98% • Dissolved in plasma – to % – Hemoglobin • Main component of RBCs • Protein containing iron © 2011 The McGraw-Hill Companies, Inc All rights reserved 1710 Functions and Composition of Blood (cont.) • White blood cells – leukocytes – Protect against infection – Granular • Basophils • Eosinophils • Neutrophils – Agranular • T and B lymphocytes • monocytes © 2011 The McGraw-Hill Companies, Inc All rights reserved 1729 Performing Common Blood Tests • Results aid in diagnosis • POLs often only perform waived tests Know office policy â 2011 The McGraw-Hill Companies, Inc All rights reserved 1730 Performing Common Blood Tests (cont.) • Chemicals in lab – Anticoagulants – keep blood in uncoagulated state – Serum separators – form a gel-like barrier between serum and clot in coagulated sample – Stains – color particular cells © 2011 The McGraw-Hill Companies, Inc All rights reserved 1731 Hematologic Tests • Blood counts – RBC count – White blood cells – Differential white blood cell – Platelet – Hematocrit – Hemoglobin Centrifuged Capillary Sample © 2011 The McGraw-Hill Companies, Inc All rights reserved 1732 Hematologic Tests (cont.) • Morphologic studies – Morphology – study of shape and form of objects – Requires special training • Coagulation tests – Identification of potential bleeding problems – Monitor therapeutic drug levels for anticoagulants – PT and PTT © 2011 The McGraw-Hill Companies, Inc All rights reserved 1733 Hematologic Tests (cont.) • Erythrocyte sedimentation rate – Measures rate of RBCs falling to the bottom of the blood sample – Must be performed on a fresh sample – Tube must contain an anticoagulant – Read after one hour – Recorded as mm/hr © 2011 The McGraw-Hill Companies, Inc All rights reserved 1734 Chemical Tests • Rarely performed in the POL • Waived tests – Blood glucose monitoring – Hemoglobin A1c – Cholesterol tests © 2011 The McGraw-Hill Companies, Inc All rights reserved 1735 Serologic Tests • Introduction of an antigen or antibody into a specimen and detection of a reaction to it • Immunoassays • Rapid screening tests – Infectious mononucleosis – HIV – Helicobacter pylori – Western blot – Radioimmunoassay (RIA) – Enzyme-linked immunosorbent assay (ELISA) – Immunofluorescent antibody (IFA) test © 2011 The McGraw-Hill Companies, Inc All rights reserved 1736 Apply Your Knowledge Matching: ANSWER: D Hemoglobin A1c _ A ESR G Lysing RBCs/evaluating the color _ B Serology test _ F Shape or form of objects C Coagulation tests C Identify bleeding problems _ D Chemical test A Rate at which RBCs fall _ E Differential E Percentage of each type of WBC _ F Morphology B ELISA _ G Hemoglobin Super! © 2011 The McGraw-Hill Companies, Inc All rights reserved 1737 In Summary 17.1 Blood is composed of plasma (the liquid portion) and formed elements Blood serves as a transport medium for oxygen, nutrients, hormones, and waste products and also attacks infecting organisms, maintains acid-base balance, and regulates body temperature 17.2 Blood is collected by one of two means: venipuncture or capillary puncture Venipuncture is the process of obtaining a blood sample from a vein, and capillary puncture is the process of obtaining blood from a superficial skin puncture © 2011 The McGraw-Hill Companies, Inc All rights reserved 1738 In Summary (cont.) 17.3 It is essential that a patient’s identity be confirmed before a blood sample is collected Correctly identifying the blood sample with the patient’s name ensures that the correct test will be done for the correct patient 17.4 Venipuncture is performed by cleansing the skin in the antecubital space, applying a tourniquet above the space, inserting a needle into the vein in the space, and withdrawing blood by way of an evacuated tube Capillary puncture involves cleansing the skin on the finger, sticking the finger with a safety lancet, and applying the drop of blood to a slide or in a small tube © 2011 The McGraw-Hill Companies, Inc All rights reserved 1739 In Summary (cont.) 17.5 The supplies needed to perform a venipuncture include VACUTAINER components (safety needle, needle holder/adapter, collection tubes), antiseptic and cotton balls or antiseptic wipes, tourniquet, sterile gauze squares, and sterile adhesive bandages Capillary puncture requires capillary puncture device (a safety lancet or an automatic puncture device such as Autolet or Glucolet), antiseptic and cotton balls or antiseptic wipes, sterile gauze squares, sterile adhesive bandages, reagent strips, micropipettes, and smear slides © 2011 The McGraw-Hill Companies, Inc All rights reserved 1740 In Summary (cont.) 17.6 All waste generated during blood-drawing procedures should be disposed of immediately Sharps should be placed in the sharps container after activating the safety device, and gloves, gauze, and other disposable supplies should be placed in a biohazard container 17.7 Patients are often concerned about pain, bruising, and scarring when having blood drawn They are sometimes afraid that they may have a serious disease, especially if large amounts of blood are drawn Good communication by the medical assistant is the key to easing these fears © 2011 The McGraw-Hill Companies, Inc All rights reserved 1741 In Summary (cont.) 17.8 There are always patients who will have special needs, including children, the elderly, patients who have bleeding disorders, and difficult patients Each patient will present a special set of challenges and should be treated with the utmost care and concern 17.9 The most common tests performed in a physician’s office laboratory include hematologic tests, chemical tests, and serologic tests © 2011 The McGraw-Hill Companies, Inc All rights reserved 1742 In Summary (cont.) 17.10 Hematologic, chemical, and serologic tests require special care when performing them The medical assistant should review the manufacturer’s instructions carefully for important information about correctly performing each test © 2011 The McGraw-Hill Companies, Inc All rights reserved 1743 End of Chapter 17 Blood will tell, but often it tells too much ~ Don Marquis © 2011 The McGraw-Hill Companies, Inc All rights reserved ... reserved 17 11 Functions and Composition of Blood (cont.) • Platelets – thrombocytes – Fragments of cytoplasm – Essential for clot formation • Plasma – Clear, yellow liquid – Contains formed elements... equipment and supplies required for blood-drawing procedures 17. 6 Discuss the correct procedures for disposing of waste generated during blood-drawing procedures 17. 7 Discuss common fears and concerns... reserved 17 17 Drawing Blood • Not all states permit medical assistants to draw blood • Venipuncture – Puncture of a vein – Most common sites are in the antecubital fossa and forearm Common Sites for