Introduction to Clinical Pathology

Question 1

Clinical

Answer 1

Referring to observations or treatment of patients in a clinic/hospital or bedside setting

Question 2

Clinical Pathology

Answer 2

The study of disease in the clinical setting, typically by the use of laboratory tests

Question 3

Pathology

Answer 3

The study of disease

Question 4

OSHA

Answer 4

-Occupational Safety and Health Administration
-Works to minimize possibilities of workplace injuries
-Mandates specific laboratory practices to protect health and safety of employees
-Some states have regulations that supersede federal OSHA regulations

Question 5

What are the 4 categories of methods for minimizing potential workplace hazards?

Answer 5

-Engineering controls
-Administrative controls
-Procedural controls
-PPE

Question 6

Engineering controls

Answer 6

Focused on changing work environment to eliminate or minimize exposure to hazard (ex: fume hood)

Question 7

Administrative controls

Answer 7

Involve creation of specific protocols to minimize worker exposure to hazard, found in Chemical Hygiene Plan (CHP)

Question 8

Procedural controls

Answer 8

Involve the development of policies that modify worker behavior

Question 9

PPE

Answer 9

Utilized when other methods are not fully effective for the removal of a hazard

Question 10

Chemical Hygiene Plan (CHP)

Answer 10

Must contain the following:

-Specific details about chemical hazards present in the workplace
-Scope and extent of worker training and documentation of that training
-Criteria for the use of PPE
-Precautions for handling hazardous chemicals, monitoring of exposure, and specific actions required when exposure occurs, including the medical care required

Question 11

Material Safety Data Sheets

Answer 11

-Provided by chemical manufacturer
-Provide recommendations for chemical safety, storage equipment, PPE, and emergency procedures
-OSHA recommends use of a specific 16-section format for MSDSs

Question 12

Aerosols

Answer 12

-Small airborne drops of liquid
-Can contain microorganisms and zoonotic disease (brucellosis, tuberculosis, psittacosis)

Question 13

Biological Safety Cabinets

Answer 13

-Used when performing procedures that can generate microbial aerosols
-Designed to prevent air from flowing out of cabinet into the room unless it has passed through a special filter capable of removing the small of particles (high-efficiency particulate air [HEPA] filter)

Question 14

Air-handling systems

Answer 14

-Air-handling system within a veterinary clinic should move air from lower to higher risk areas only
-Laboratories should ideally be under negative pressure (less air pressure relative to exterior) and shouldn’t be recirculated after it passes through the laboratory

Question 15

Autoclave

Answer 15

-Instrument that uses moist heat at a greater than atmospheric pressure
-Material that’s considered to be very hazardous is autoclaved longer than usual
-If autoclave is not available for laboratory itself, infectious materials should be double-bagged and carried in a leakproof, sterilizable containers to autoclave

Question 16

Laboratory Disinfection

Answer 16

-Workbenches and other hazardous surfaces should be decontaminated at the end of the day and immediately after a spill with 70% ethanol or a 0.5% solution of sodium hypochlorite (dilute bleach)
-Spills should have a minimum of 10 minutes of contact time with the decontamination solution
-Surfaces of equipment like centrifuges should be wiped with disinfectant

Question 17

The Bloodborne Pathogens Standard

Answer 17

-Includes OSHA mandates to protect workers from infection with infectious agents that are present in the bloodstream
-Also incorporates the Needlestick Safety and Prevention Act of 2001

Question 18

OPIM

Answer 18

-Other potentially infectious materials
-Regulations less specific than bloodborne pathogens except when they have potential to cause serious threats to public health and safety (bacterial organisms that cause anthrax, botulism, and plague)

Question 19

Biohazards and Biosafety Levels

Answer 19

-Biological substances that pose a threat to human health and substances that are harmful to animals
-Biosafety Levels are graded at 1-4 (I-IV)
-The higher the number, the greater the degree of risk

Question 20

Biosafety Level 1

Answer 20

-Agents that ordinarily do not cause disease in humans; may affect individuals with immunodeficiencies
-Includes soaps, cleaning agents, vaccines administered to animals, species-specific infectious diseases such as canine infectious hepatitis
-No specific requirements for handling/disposal other than normal sanitation that would be used in a home kitchen

Question 21

Biosafety Level 2

Answer 21

-Agents that have the potential to cause human disease if handled incorrectly
-Hazards may result from MM exposure, oral ingestion, or puncture of the skin
-Examples include bacterial agents that cause toxoplasmosis and salmonellosis; substances in this group generally have a low potential for aerosol contamination
-Limited access to area, warning signs, PPE, sharps containers, instructions for disposal and handling

Question 22

Biosafety Level 3

Answer 22

-Agents that can cause serious and potentially lethal diseases
-Potential for aerosol respiratory transmission is high
-Example: Mycobacterium tuberculosis
-Primary and secondary barriers required to protect personnel, controlled access, decontamination of waste, cages, clothing, and other equipment, use of PPE

Question 23

Biosafety Level 4

Answer 23

-Agents pose a high risk of causing life-threatening diseases
-Examples: Ebola, Marburg viruses, other dangerous and exotic agents
-Maximum containment exercised; shower-in and shower-out procedures, full body suits equipped with positive air supply, extensive training for individuals who plan to work in these facilities

Question 24

Shipping Hazardous Material

Answer 24

-Regulations are mandated by U.S. Department of Transportation
Infectious materials are classified as Category A or Category B depending on risks associated exposure to the materials

Question 25

Infectious Materials - Category A

Answer 25

-Poses higher degree of risk, includes materials that are known or likely to contain infectious agents that could cause permanent disability, life-threatening disease, or fatal disease to healthy humans or animals who are exposed to the material
-Examples include Bacillus anthracis, Coccidioides immitis, Mycobacterium tuberculosis, and West Nile virus

Question 26

Infectious Materials - Category B

Answer 26

-Materials that contain an infectious agent that is not in a form that could cause permanent disability, life-threatening disease, or fatal disease in healthy humans or animals exposed to the material
-Most diagnostic samples from veterinary practices sent to outside laboratories for analysis fall into Category B

Question 27

Metric System Units

Answer 27

-Laboratory measurements are performed using the metric system units
-Gram (weight), Liter (volume), Meter (length)

Question 28

Mathematic Rules in Clinical Laboratories

Answer 28

-Small amounts are represented in decimal notation, not fractions
-Amounts less than 1 are always written with a 0 in front of the decimal point
-Cubic Centimeter = Milliliter, though milliliter is the correct designation for use in medicine
-The only ratio that is usually expressed as a decimal in veterinary technology is specific gravity, which represents the weight of a substance relative to the weight of the same volume of water

Question 29

Abstract and Concrete Numbers

Answer 29

-Abstract or pure numbers have no unit designations
-Concrete or denominate numbers have specific values
-Numbers of different denominations can’t be used together in mathematical operations

Question 30

International System of Units

Answer 30

-Abbreviated SI
-SI units are designated for 7 different types of measurements: length, mass, time, electric current, temperature, luminosity, and quantity
-SI units of importance in veterinary clinic laboratories are mass, temperature, and quantity

Question 31

Converting a number into an exponential form

Answer 31

-Move the decimal point so that the first term is more than 1 and less than 10
-The second term is a power of 10 that is equal to the number of times that the decimal point was moved
-The sign (+ or −) determines the direction in which to move the decimal. The use of + means that the decimal point was moved to the left; the use of − means that the decimal point was moved to the right
-Example: 6,097,000 would be 6.097 x 10^6

Question 32

pH and Logarithms

Answer 32

-Logarithmic notation expresses numbers as powers of 10
-pH scale is an example of practical application of logarithmic notation
-pH is defined as the negative logarithm of the hydrogen ion concentration of a solution (H+)
-Example: A solution with an H+ concentration of 10^-7 has a pH of 7
-The difference between any 2 consecutive numbers on the pH scale represents a power of 10 difference in H+ concentration

Question 33

pH values

Answer 33

-A pH of 7 is considered a neutral solution
-A pH of more than 7 is indicates an alkaline or basic solution
-A pH of less than 7 indicates an acid solution

Question 34

Points of Equivalence in Temperature

Answer 34

Absolute zero K = -273 Celsius = -459.4 Fahrenheit

Question 35

Fahrenheit Scale vs. Celsius Scale

Answer 35

-Fahrenheit: Water freezes/ice melts at 32 degrees and boils at 212 degrees
-Celsius: Difference between freezing/melting point and boiling points is 100 degrees
-Each degree in the Celsius scale is equivalent to 1.8 or 9/5 degrees in the Fahrenheit scale

Question 36

Fahrenheit and Celsius Conversion Equations

Answer 36

C = 5/9(F-32)
F = 32 + 9/5C

Question 37

Kevin Scale

Answer 37

-Begins at absolute zero and has no negative numbers
-Converting to kelvins is accomplished by adding 273 to the temperature in Celsius
-Temperatures reported as kelvins do not involve the use of the term degrees, just the letter K
-Example: 30 degrees Celsius = 303 K

Question 38

Purpose of Refractometer

Answer 38

Used to determine the specific gravity of urine samples and the total protein content of fluid cytology samples and serum samples

Question 39

Refraction and Specific Gravity

Answer 39

-The bending of light rays as they pass from one medium into another that has a different optical density
-Degree of refraction is a function of the concentration of solid material in the medium
-Specific gravity or protein concentration of a solution is directly proportional to its concentration of dissolved substances
-Value is read at the distinct light-dark interface

Question 40

Refractometer Types and Species

Answer 40

-Many are configured for human samples, so animal samples may require dilution before evaluation
-Refractometers are available that are calibrated for canine, feline, and equine samples
-Refractive index of some species correlates to a unique urine specific gravity, so these veterinary-specific refractometers are calibrated to account for those differences
-Newer refractometers are digital and contain a microprocessor that provides automatic calibration and temperature monitoring

Question 41

Refractometer Use and Care

Answer 41

-Refractometer should be cleaned after each use
-The prism cover glass and cover plate should be wiped dry with lens paper ONLY as this protects the optical surfaces from scratches
-Calibration should occur weekly or daily depending on use
-Distilled water at room temperature placed on the refractometer should have a zero refractive index and read at 1.000 on the specific gravity scale
-If there is deviations from the zero mark by more than one-half a division, the refractometer is adjusted by turning the adjusting screw as directed by the manufacturer
-The refractometer should not be used if it is not calibrated to zero with distilled water