Module 1 - Risk Management and Safety in the Histopathology Laboratory

RISK MANAGEMENT

process of ensuring and maintaining personal as well as environmental health and safety in the laboratory

EVERYONE’S RESPONSIBILITY

It is __________ to minimize risks associated with day-to-day activity by using safety guards and checking the quality of reagents

FIRST STEP IN RISK MANAGEMENT

to identify all electrical, mechanical and biological hazards that can potentially cause harm in and emanating from the laboratory

PREPARING AN INVENTORY OF CHEMICAL REAGENTS

not enough to identify hazards in histotechnology. An inventory of chemical reagents must be on hand and obsolete chemicals should be routinely disposed of

STANDARD OPERATING PROCEDURES

must be detailed to include control of hazardous specimens, risk assessments, and other health and safety information relevant to handling specimens

STANDARD OPERATING PROCEDURES

A set of written, are usually mandated by accrediting or regulatory agencies to ensure that the laboratory is safe. This includes detailed procedures for handling hazardous substances and personal hygiene practices.

POOR PROCESSING OF TISSUES OR INACCURATE STAINING RESULTS

Equipment malfunction due to poor maintenance and poor-quality reagents can result in

CUTTING OF ONE’S FINGER/ HAND IN MICROTOME KNIVES

One of the most common accidents in the laboratory involves

MATERIAL SAFETY DATA SHEET

All hazardous agents must be listed and evaluated, including normal use, disposal, and risks associated with spillage.

CHEMICAL, BIOLOGICAL, PHYSICAL AND RADIOACTIVE HAZARDS, AS WELL AS MUCULOSKELETAL STRESSES

Laboratory workers are exposed to numerous potential hazards including

SAFETY TRAINING & ENFORCEMENT OF LABORATORY SAFETY POLICIES

Measures to protect against laboratory accidents include

FUME HOOD/ OTHER SUITABLE CONTAINMENT DEVICE

Procedures involving volatile toxic substances and those involving solid or liquid toxic substances should be conducted in a

TO AVOID THE UNNECESSARY PURCHASE OF CHEMICAL MATERIALS

a detailed list of chemical materials must be prepared. Only a minimum amount of volatile chemicals must be kept in the laboratory.

COMBUSTIBLE CHEMICAL MATERIAL

stored in a heat resistant cabinet

ACIDS AND BASES

must be separately stored

SAND, “KITTY LITTER” OR A COMMERCIAL PRODUCT

Used chemicals must not be released into soil, drains and waterways. Use an absorbent such as ____________ to collect spills and contain spread

• MICROSCOPY

• MICROTOME

• CRYOSTAT

• AUTOTECHNICON

• AUTOMATED COVERSLIPPER

• AUTOMATED H & E STAINER/ AUTOMATED SLIDE STAINER

THE MAJOR PIECES OF EQUIPMENT FOR ANY SURGICAL PATHOLOGY LABORATORY:

○ Name, manufacturer, model number and serial number

○ Record of preventive maintenance performed, as prescribed by the manufacturer

○ Record of service calls and repairs performed

○ Copy of operating manual

It is imperative that the laboratory maintain a current file for every piece of equipment in the laboratory:

READ THE MANUAL THAT ACCOMPANIES THE EQUIPMENT

The first and most important step in the operation of any piece of equipment is to

MICROSCOPE

enlarges images and allows the visualization of morphologic cellular details that are too small to be seen by the naked eyes

STAINS AND DYES

used to give contrast to the tissue by creating light absorption of varying degrees

PATHOLOGIST & HISTOTECHNOLOGIST

The microscope is one piece of equipment that is used by both the

PATHOLOGIST

views the slide to identify a disease process or abnormality that will directly affect the patient’s treatment

HISTOTECHNOLOGIST

views the same slide microscopically for quality control, to determine whether all technical processes are functioning properly and if a slide of a diagnostic quality has been achieved

• BASE

• ARM

• STAGE

• SUBSTAGE

• MECHANICAL STAGE

MAIN FRAMEWORK

BASE

Provides support for the microscope

BASE

should be large and solid enough to allow the microscope to stand by itself

ARM

Supports and holds the magnifying and adjustment system

ARM

It can be used as a handle for carrying the microscope

STAGE

This is the flat platform where the slide is placed for examination

SUBSTAGE

It is located directly under the stage and holds the condenser and diaphragm

MECHANICAL STAGE

Permits movement of the stage while holding the slide in the phase of focus

• NOSEPIECE

• OBJECTIVES

• BODY TUBE

• EYEPIECE

• FOCAL LENGTH

PARTS OF THE LENS SYSTEM:

NOSEPIECE

It is located at the end of the body tube for holding the objectives

OBJECTIVES

Consist of a system of lenses located at the end of the body tube that is held in place by the nosepiece and is closer to the slide under examination

OBJECTIVES

The purpose of the __________ is to increase or decrease magnification

OBJECTIVES

The ______ are mounted on a revolving turret allowing for the change of objectives

EYEPIECE

It is also referred to as the ocular

EYEPIECE

This is the lens system nearest the eye

EYEPIECE

The ocular receives the image from the lens of the objective, further magnifying the object being examined by approximately 10x

FOCAL LENGTH

It is the distance between the outer lens of objectives and the cover glass of the slide under examination

MAGNIFICATION

the process that increases the size of the structure under examination. It is achieved by the use of the microscope's lens system

TOTAL MAGNIFICATION OF A MICROSCOPE

the product of the magnifying power of the objective and eyepiece, with a normal tube length of 160 mm

180 mm

WORKING TUBE LENGTH

160 mm

NORMAL TUBE LENGTH

LIGHT BULB

built into the base below the substage

CRITICAL MICROSCOPY

requires a lamp with condensing lens and a diaphragm

COMPOUND MICROSCOPE

The most common (and the first to be invented)

COMPOUND MICROSCOPE

uses light to image the sample

• ELECTRON MICROSCOPE

• TRANSMISSION ELECTRON MICROSCOPE

• SCANNING ELECTRON MICROSCOPE

• ULTRA-MICROSCOPE

• VARIOUS TYPES OF SCANNING PROBE MICROSCOPE

Other major types of microscopes are:

COMPOUND MICROSCOPE

a microscope with more than one lens and its own light source

COMPOUND MICROSCOPE

In this type of microscope, there are ocular lenses in the binocular eyepieces and objective lenses in a rotating nosepiece closer to the specimen

COMPOUND MICROSCOPE

Because it contains its own light source at its base, It is also considered a bright field microscope, which means that the specimen is lit from below and viewed from above

SURGICAL PATHOLOGY

The compound microscope currently in use for

• LENS SYSTEM CONDENSER

• OBJECTIVE

• OCULAR

COMPOUND MICROSCOPE CONSISTS OF:

LENS SYSTEM CONDENSER

Brings parallel rays of light to a point of focus in the plane of the object

OBJECTIVE

Magnifies the object being viewed and focuses a real image in the upper part of the body tube

OCULAR

Further magnifies the image formed by the objective

• MONOCULAR HEADS

• BINOCULAR HEADS

• TRINOCULAR HEADS

VIEWING HEADS

MONOCULAR HEADS

Only use one eyepiece when viewing the specimen

MONOCULAR HEADS

are light weight and are inexpensive

BINOCULAR HEADS

Have two eyepieces and are more convenient and comfortable to use

BINOCULAR HEADS

It is the most common choice

TRINOCULAR HEADS

Have a third eyepiece tube that can be used by another person simultaneously or by an LCD camera

TRINOCULAR HEADS

more expensive than the other two types

TRINOCULAR HEADS

Usually the heads can be set to a 45 degree or a 30 degree angle with sliding or hinge adjustment for inter-pupillary distance

BRIGHT FIELD MICROSCOPY

used in compound microscopes, where light is either passed through, or reflected off, a specimen

BRIGHT FIELD MICROSCOPY

derived from the fact that the specimen is dark and contrasted by the surrounding bright viewing field

SIMPLE LIGHT MICROSCOPES

sometimes referred to as bright field microscopes where a specimen is placed on the stage of the microscope and incandescent light from the microscope’s light source is aimed at a lens beneath the specimen

BRIGHT FIELD MICROSCOPY

the simplest and most popular of all techniques used for illumination of samples in light microscopes

DARK SAMPLE ON A BRIGHT BACKGROUND

The typical appearance of a bright field microscopy image is a

DARK FIELD MICROSCOPY

used to observe unstained and transparent samples causing them to be clearly visible and appear brightly lit against a dark, almost purely black background

STEREOMICROSCOPES & CONVENTIONAL COMPOUND MICROSCOPES

The principal elements of dark field illumination are the same for both

PHASE CONTRAST MICROSCOPY

converted into amplitude or contrast changes in the image

PHASE CONTRAST MICROSCOPY

This microscope technique makes it possible to study the cell cycle in live cells

PHASE CONTRAST MICROSCOPY

does not require staining to view the slide

PHASE CONTRAST MICROSCOPY

It is a type of light microscopy that enhances contrasts of transparent and colorless objects by influencing the optical path of light

PHASE CONTRAST MICROSCOPY

able to show components in a cell or bacteria which would be very difficult to see in an ordinary light or bright field microscope

POLARIZED LIGHT MICROSCOPY

improves the quality of the image obtained with birefringent materials when compared to other techniques such as bright field microscopy, phase contrast microscopy and dark field microscopy

POLARIZED LIGHT MICROSCOPY

It is designed to examine specimens that are visible primarily due to their optically anisotropic character

• POLARIZER

• ANALYZER

ESSENTIAL COMPONENTS OF POLARIZED LIGHT MICROSCOPY:

FLUORESCENCE MICROSCOPE

refers to any microscope that uses fluorescence to generate an image

FLUORESCENCE MICROSCOPE

many wavelengths of light, ranging from the ultraviolet to the visible can be used to cause samples to fluoresce and allow viewing by eye or with the use of specifically sensitive cameras

FLUORESCENCE MICROSCOPE

a precision instrument intended for microscopic detection of tubercle bacilli in specimens in the routine diagnostic TB laboratory.

FLUOROCHROMES

allows smear examination at lower magnification than is used for light microscopy

• XENON ARC LAMPS

• MERCURY-VAPOR LAMPS WITH AN EXCITATION FILTER

• LASERS

• HIGH-POWER LEDs

Four main types of light source are used, including:

ELECTRON MICROSCOPE

uses a beam of accelerated electrons as a source of illumination

MAGNETIC LENSES

The electron beam is focused with

MOIST PAPER TOWEL

Dirt must be removed from the microscope frame and mechanical parts by dabbing with

IMMERSION OIL

essential in maximizing the microscope's optical performance, but its improper use or failure to immediately remove the oil after each use constitutes the most serious contaminant that must be dealt with in instrument maintenance

QUALITY CONTROL

The quality of sections and quality of staining produced by the histopathology laboratory must be checked before issuing them to the pathologist

RECOGNIZING WORKPLACE HAZARDS

An important first step in protecting worker health and safety is

• CHEMICAL

• PHYSICAL

• ELCTRICAL

Most hazards encountered fall into three main categories:

BIOHAZARDS

Refer to anything that can cause disease in human, regardless of its source

CHEMICAL HAZARDS

Cleaning agents and disinfectants, drugs, anesthetic gases, solvents, paints, and compressed gases are examples of

• IRRITANTS

• CORROSIVE CHEMICALS

• SENSITIZERS

• CARCINOGENS

• TOXIC MATERIALS

DIFFERENT TYPES OF CHEMICALS:

IRRITANTS

Chemicals that cause reversible inflammatory effects at the site with living tissue, especially the skin, eyes and respiratory passages

CORROSIVE CHEMICALS

Cause destruction or irreversible alterations when exposed to living tissue, or destroy certain inanimate surfaces (generally metal)

SENSITIZERS

Cause allergic reactions in a substantial proportion of exposed subjects, not just in hypersensitive individuals

CARCINOGENS

Substances that can induce tumors, not only in experimental animals but also in humans