Diagnostic Tests Diagnostics Chapter 6 Copyright  2014 Pearson Canada Inc. 6-1

Diagnostic Tests A healthy body is in a state of homeostasis. Each part of the body has what is called a normal or reference range. If levels fall above or below this range, further investigation or treatment is pursued. Purposes: Assist in diagnosis Evaluate treatment Establish a baseline Reduce or prevent disease To comply with the law Copyright  2014 Pearson Canada Inc. 6-2

Diagnostic Tests Health care is based on information gathered from a variety of sources. Diagnostic testing done by laboratory and diagnostic imaging departments provide the information to assist in the diagnosis of disease and monitoring of a client’s progress. Copyright  2014 Pearson Canada Inc. 6-3

Testing facilities Diagnostic testing is done in licensed clinical laboratories and diagnostic imaging facilities, both private and within hospitals. A limited number of tests are performed in physicians’ offices. Can you think of tests we may perform in a physician’s office? Copyright  2014 Pearson Canada Inc. 6-4

Testing facilities MHSC approved laboratories are often centrally located, with satellite labs in medical buildings. These facilities offer clinical laboratory services, including routine testing on blood and other body fluids and tissue analysis. Diagnostic imaging provides a detailed view of structures beneath the skin and are usually performed in a WRHA site. Let’s find some lab addresses. Find this website https://www.dynacare.ca/ Copyright  2014 Pearson Canada Inc. 6-5

Professionals involved in diagnostic testing Phlebotomist – Primary duty is to draw blood specimens. Medical laboratory technologist (MLT) – is proficient in all areas of clinical laboratory work. Hematologist – is a physician who specializes in the diagnosis, treatment, prevention, and/or investigation of disorders of the blood and lymphatic systems. Copyright  2014 Pearson Canada Inc. 6-6

Professionals involved in diagnostic testing Pathologist – is a medical doctor who examines tissue samples and interprets results. Radiologist– is a physician who specialized in interpreting images. Copyright  2014 Pearson Canada Inc. 6-7

Commonly ordered tests Complete Blood Count (CBC) – Test that provides information about the blood and blood-forming tissues, body systems and overall health. Red Blood Cell Count (RBC) – Test that counts the number of red blood cells in a volume of blood. Hemoglobin (Hb) – Hemoglobin is a protein on the red blood cells that attaches to oxygen in the blood; it helps circulate oxygen and remove carbon dioxide. Copyright  2014 Pearson Canada Inc. 6-8

Commonly ordered tests White Blood Cell Count (WBC) – White blood cells are the body’s primary means of fighting infection, the WBC determines the total number of white cells in the blood. Platelet Count – Test that counts the number of platelets or thrombocytes in a given volume of blood. Coagulation Study – Test that measures the clotting time of the blood. Copyright  2014 Pearson Canada Inc. 6-9

Commonly ordered tests Chemistry tests urine, blood plasma, and other body fluids. e.g. blood sugar level, electrolytes, blood urea nitrogen (BUN) and various enzyme tests. Creatinine – Excess creatinine in the blood indicates possible renal dysfunction. Electrolytes – Testing levels of sodium, potassium & chloride. Blood Glucose Levels – Metabolic diseases, such as diabetes mellitus are diagnosed by measuring the body reaction to increase/decrease of blood sugar. Copyright  2014 Pearson Canada Inc. 6-10

Commonly ordered tests Cholesterol/Triglycerides – These tests measure types of fats in the blood. Heart (Cardiac) Enzymes – The heart is damaged after a myocardial infarction; as a result cardiac enzymes are released. This test confirms the actual heart attack and extent of damage to the muscle. Copyright  2014 Pearson Canada Inc. 6-11

Commonly ordered tests Microbiology studies body fluids/tissues for infectious organisms, such as bacteria, viruses, parasites and fungi. Tests include urine, sputum, blood cultures & stool culture. Culture and Sensitivity (C&S) - A set of tests performed on a clinical specimen, where isolation of a potentially pathogenic bacterium is followed by antibiotic susceptibility testing. Let’s find some normal ranges on the Dynacare website Copyright  2014 Pearson Canada Inc. 6-12

Commonly Diagnostic Imaging ordered tests Diagnostic imaging includes computed tomography (CT), magnetic resonance imaging (MRI), and ultrasonography. X-ray – is a visual image of a body part created by using low doses of radiation reflected on film or fluorescent screen. Ultrasonography (US) – uses sound waves to produce pictures of soft-tissue structures within the body. Copyright  2014 Pearson Canada Inc. 6-13

Commonly ordered tests Barium Swallow/Enema – Visual examination of specific parts of the digestive tract; a contrast medium is introduced to allow for monitoring on a fluoroscope. Colonoscopy – Visual examination of the large intestine. Gastroscopy - Visual examination of the lining of the esophagus, stomach and first part of the small intestine. Copyright  2014 Pearson Canada Inc. 6-14

Commonly ordered tests Proton Emission Tomography (PET) – A 3D image of functioning body parts, e.g. Beating heart or blood flow. Computed Tomography (CT) – Cross-sectional images of any part of the body. Magnetic Resonance Imagining (MRI) – Analysis of how radio frequency pulses cause protons within the body to realign with the external magnetic field. Copyright  2014 Pearson Canada Inc. 6-15

Commonly ordered tests Electrocardiogram (ECG) – Test that records the electrical activity of the heart. Holter Monitoring – A portable test that continuously records the electrical activity of the heart over a longer period of time. Angiogram – Also called cardiac catheterization. A dye is injected via a catheter and x-rays are taken of the arteries. Copyright  2014 Pearson Canada Inc. 6-16

Health teaching Client education is the single most important factor in successful tests. Tests can be accurate only if clients understand how to prepare from them, and it is the job of the AHP to direct, advise and coach the client in preparation of the test. Copyright  2014 Pearson Canada Inc. 6-17

Health teaching Clients need to know: When and where to go for the test How to prepare for it What exactly will happen? How long will it take? Does it hurt? Can I drive home after? Time off from work? Copyright  2014 Pearson Canada Inc. 6-18

Health teaching A well informed client will be less apprehensive, compliant with preparation instructions, and more cooperative at the time of the test. Providing the client with oral and written instructions is helpful; as is a reminder call a day or so before the test. Copyright  2014 Pearson Canada Inc. 6-19

Requisitions Almost all tests require a requisition ordered by the doctor. Make a note in the clients chart that a test has been requisitioned and when and how the client was notified of date/time of test. Copyright  2014 Pearson Canada Inc. 6-20

Preparing and Handling Specimens Instruct the patient Ensure you are preparing the specimen in the treatment room and following safety precautions. Label the specimen Prepare the requisition – ensure all required information is on the specimen. Prepare for transport Place the specimen in the appropriate area for lab pickup Copyright  2014 Pearson Canada Inc.

Receiving and Recording Test Results Go to page 170 Copyright  2014 Pearson Canada Inc.

Chapter 6 summary Diagnostic tests are ordered by a physician to gain information to diagnose and monitor clients’ conditions. Tests are processed by medical laboratories, which may be part of a hospital or independent. Laboratories are specialized, e.g. Hematology for blood work, Pathology for tissue samples, and Diagnostic Imaging for x-rays and ultrasound. Copyright  2014 Pearson Canada Inc. 6-23

Chapter 6 summary continued Among the more common tests are complete blood count, electrolyte, blood glucose levels, cholesterol, and culture and sensitivity for the presence of pathogens. X-rays, barium swallow/enema, ultrasound, CT scan, magnetic resonance imaging (MRI), and endoscopies are all examples of diagnostic tests. Copyright  2014 Pearson Canada Inc. 6-24