RISK MANAGEMENT AND SAFETY IN THE HISTOPATHOLOGY LABORATORY

• Risk management


  Pertains to personal and environmental health and safety
• Steps in risk management

  1. Identify all the hazards in and emanating from the lab

  2. Prepare an inventory of chemical reagents

  3. Include electrical, mechanical, and biological hazards

  4. Properly dispose of obsolete chemicals
• Standard Operating Procedures (SOP)

  Must be detailed to include: control of hazardous substances, risk assessment, and other health and safety information relevant to handling specimens
• Equipment malfunction due to poor maintenance and poor-quality reagents

  Can result in poor processing of tissues or inaccurate staining results
• Preventive maintenance and quality control

  Necessary to minimize risks associated with day-to-day activity
• The most common accident is cutting of one's finger or hand on microtome knives
• Incident reporting and investigation

  1. All incidents and accidents must be reported

  2. Each incident should be investigated

  3. Additional measures should be taken to ensure the incident does not happen again

  4. Everything must be documented and reported to the infectious officer
• Autotechnicon


  An automatic tissue processing machine which fixes, dehydrates, clears, and infiltrates tissues, decreasing the time and labor needed during the processing of tissues
• Microtome


  An instrument used to cut tissues into thin slices, producing 4-6 μm thickness

  
• Automated coverslipper


  Used during the mounting procedure to ensure lesser bubbles and no spaces on the specimen
• Automated H&E stainer/Automated slide stainer

  Reduces the fear of over or under staining, as it is timed and programmed
• Cryostat


  Has a built-in microtome and a freezing chamber, used for rapid diagnosis
• Preventive maintenance of equipment

  1. Maintain a current file for every piece of equipment

  2. Record of preventive maintenance, service calls, repairs, and operating manual
• First and most important step in the operation of any equipment is to read the manual
• Orienting new employees on equipment

  1. Each piece of equipment should have a checklist

  2. Checklist should be administered by an experienced technologist

  3. Checklist prescribes appropriate use and ensures safe and effective use
• Parts of a compound microscope

  • Base
  • Arm
  • Stage
  • Substage
  • Mechanical stage
  • Nosepiece
  • Objectives
  • Body tube
  • Eyepiece
  • Focal length

  
• Magnification


  • The process that increases the size of the structure under examination
  • Total magnification is the product of the magnifying power of the objective and eyepiece
• Types of microscope viewing heads

  • Monocular
  • Binocular
  • Trinocular

  
• Microscopy techniques


  • Bright field
  • Dark field
  • Phase contrast
  • Polarized light
  • Fluorescence
  • Electron

  
• Daily care and maintenance of microscope

  1. Dust microscope and lenses

  2. Remove immersion oil immediately

  3. Check for dust on eyepiece and condenser

  4. Cover microscope when not in use

  5. Use air bulb to remove dust
• Lenses


  • Should never be touched as misalignment can cause eyestrain to the user
  • Should be wiped daily and as necessary with fresh lens paper (rough paper or cloth will cause scratching of the lens)
• Immersion oil


  • Should be removed immediately after use
  • Can be removed using a lens paper damped with xylene
• Daily cleaning of microscope

  1. Dust microscope and the outer surface of lenses objective with lens paper

  2. The top lens of the eyepiece should be polished to remove dust or finger marks, and microscope should be checked for critical illumination

  3. Rotation of the eyepiece will show if any dust is present. If so, the eyepiece may need to be dismantled and both lenses cleaned

  4. Substage condenser should be checked for dust. If dust is present on the condenser, the object being viewed will come in and out of focus when racked up and down – always focus UP!

  5. The microscope should be covered when not in use

  6. Removal of dust should be done with an air bulb

  7. Always support the microscope when carrying. It should be cradled one hand holding it by the arm, the other supporting the base. The best way to carry a microscope is in its case
• Quality control in histopathology lab

  • Quality of sections and staining produced must be checked before issuing to the pathologist
  • Special stains to identify tissue components/microorganisms must always be accompanied by parallel staining of a section from a control known to have the component under study
  • QC is done every day to make sure that the machine's running ability is within acceptable range
  • The different application dyes in the lab are also checked and filtered just to make sure that there are no precipitates on the slide, unacceptable debris that will confuse the reader/medical technologist as well as the pathologist
• Elements of a set of written, standardized operating procedures (SOPs) mandated by accrediting or regulatory agencies

  • Handling hazardous substances
  • Personal hygiene practices
  • Records of regulatory compliance
  • Risk assessment
  • Causes and prevention of occupational injury or illness
  • Health and safety training
  • Personal protective equipment (PPE)
  • Hazardous waste disposal practices/management which should be kept indefinitely
• The American Society of Clinical Pathologists (ASCP) has established a special certification in lab safety for medical and histological technicians and technologists (yearly training)
• Risk assessment steps


  1. Identify the hazards

  2. Decide who might be harmed and how

  3. Evaluate the risks and decide on the precautions

  4. Record your findings and implement them

  5. Review your assessment and update if necessary
• Unidentifiable, questionable, old or obsolete reagents and chemicals in poorly labeled containers should be set aside for disposal
• Material safety data sheets (MSDS)


  • A file of hazardous chemicals is now available from databases on the Internet and should be readily accessible in the laboratory
  • All hazardous agents must be listed and evaluated, including normal use, disposal, and risks associated with spillage
• Biohazards


  • Anything that can cause diseases in humans, regardless of its source
  • Includes infectious agents, contaminated solutions, specimens, or objects
• Irritants


  Chemicals that cause reversible inflammatory effects at the site of contact with living tissue especially in the skin, eyes, and respiratory passages
• Corrosive


  • Destruction or irreversible alterations when exposed to living tissue or inanimate surfaces (metal)
  • A chemical maybe corrosive to tissue but not to steel or vice versa and few are corrosive to both
• Sensitizers


  • Cause allergic reactions in a substantial proportion of exposed subjects (not just in hypersensitive individuals)
  • Sensitization may occur at work because of the high exposure level
• Examples of carcinogens

  • Chloroform
  • Chromic acid
  • Formaldehyde
  • Nickel chloride (NiCl2)
  • Potassium dichromate (K2Cr2O7)
• Examples of carcinogenic dyes

  • Auramine
  • Basic fuchsin
  • Any dye derived from benzidine (congo red and diaminobenzidine)
• Toxic material


  Capable of causing death by ingestion, skin contact or inhalation at certain specified concentrations
• Examples of toxic materials

  • Methanol
  • Chromic acid
  • Osmium tetroxide
  • Uranyl nitrate
• Combustibles


  • Substances that ignite at or above a certain temperature (or flashpoint) at which vapors will ignite with the presence of an ignition source
  • Combustible liquids pose little risk of fire under routine laboratory conditions, but they will burn readily during a fire
• Flash point


  • OSHA= 100°F (38°C)
  • Department of Transportation (DOT)=141°F (60.5°C)
• Flammables


  • Substances that ignite at or below the temperature (flash points below the temperature specified above)
  • Require specially designed storage rooms, cabinets and containers to control and prevent vapors from building up around electrical devices that spark