[1S] UNIT 1: Phases of Laboratory Testing Flashcards
The systematic study of biochemical processes associated with health & disease & the measurement of constituents in body fluids or tissues to facilitate diagnosis of disease.
Clinical Chemistry
A representative portion of body fluid such as serum, plasma, urine and CSF
Patient Sample
Parts of the Spectrophotometer
LEME CPR
Light Source
Entrance Slit
Monochromator
Exit Slip
Cuvette
Photodetector
Read-out Device
T/F: Color transmitted + corresponding color and color observed + color of the observation are the same colors.
T
T/F: Color absorbed + complementary color and color observed + color of the observation are the same colors.
F; color absorbed + complementary color & color observed + color of the solution have different colors
PARTS OF SPECTROPHOTOMETER
T/F: Tungsten bulb is the most common light source - it falls to the visible-infrared
T
TYPES OF LIGHT SOURCE
Less than 400 nm wavelength, greater energy + higher frequency
UV
LIGHT SOURCE
Visibke to the UV spectrum
Mercury Bulbs
Hydrogen-Deuterium Lamp
PARTS OF SPECTROPHOTOMETER
Prevents the entry of stray light
Entrance Slit
Most common source of stray light
Deteriorating Bulb
PARTS OF SPECTROPHOTOMETER
Functions in isolating the desired wavelength of light you want to work with and allow the needed nanometees to pass through
Monochromator
2 Monochromators
- Glass Prism
- Diffraction Grating
PARTS OF SPECTROPHOTOMETER
50-1200 nm; also known as reaction vessel; measures the absorbance of a specific wavelength
Cuvette
PARTS OF SPECTROPHOTOMETER
Coverts light into electricity
Photodetector
PARTS OF SPECTROPHOTOMETER
Most sensitive and powerful type of photodetector. Also used in fluorometric assays
Photomultiplier Tube
PARTS OF SPECTROPHOTOMETER
Displays the absorbance & transmittance
Read-out Device
Color of control normal & control pathologic
Green & Red
T/F: Energy & frequency is directly proportional with wavelength.
F; indirectly
These are materials with known characteristics that are used to assess the accuracy and precision of laboratory test results.
Controls
This is a known reference material or substance that is used to calibrate or validate laboratory instruments and assays.
Standard
Role of MT
- Deliver accurate and precise laboratory information
- Provide reliable lab results
nonfunctioning waste products in the process of being cleared
Metabolites
T/F: Enzymes are intracellular in nature
T
QUALITY MANAGEMENT
“a comprehensive set of policies and procedures.”
monitors quality performance starting from the ordering of a laboratory determination to its reporting, the interpretation of results, and then
application to patient care
Quality Assurance
Quality management phases
- Pre-analytical
- Analytical
- Post analytical
test ordering → specimen collection → transporting the specimen → entering patient info → centrifugation → separating & aliquoting plasma → delivery to proper lab location
pre-analytical phase
LAB REQUESTS
“Immediately”; within 1 hour
STAT
LAB REQUESTS
2-3 hrs
Routine
FACTORS AFFECTING LABORATORY RESULTS
- Controllable
- Uncontrollable
VARIABLES AFFECTING SELECT CHEMISTRY ANALYTES
↑ in AM: adrenocorticotropic hormone (ACTH), cortisol, Fe, aldosterone
↑ in PM: acid phosphatase, growth hormone, parathyroid hormone (PTH), thyroid-stimulating hormone (TSH)
Diurnal variation
VARIABLES AFFECTING SELECT CHEMISTRY ANALYTES
↑ ACTH, cortisol, catecholamines
Stress
Information on Tube Top
- name
- other ID
- MRN
- accession number
- tube type
- collection date
- tests
COMPONENTS OF AN ANALYTICAL RUN
is to check if there are interferences in the sample
Blank
triglycerides are increased showing whitish
color
Lipemic
a pure solution of known exact concentration
wherein the unknowns are being compared
Standard or Reference Material
CHARACTERISTICS OF IDEAL CONTROLS
T/F: Should behave like real specimens and should be available in sufficient quantity to last a
minimum of 1 year
T
CHARACTERISTICS OF IDEAL CONTROLS
T/F: Should be unstable over a period of 1 year
F; Should be stable over a period of 1 year
CHARACTERISTICS OF IDEAL CONTROLS
T/F: Should be available in convenient vial volumes and vary minimally in concentration and
composition from vial to vial
T
CHARACTERISTICS OF IDEAL CONTROLS
T/F: Should be preferably heated require
reconstitution before use
F; lyophilized
SOURCES OF CONTROL: POOLED CONTROL SERA
T/F: Laboratories that prepare their own control should collect a large pool sufficient to last 1 year. The control should be analyzed at least 20 times to obtain the mean value for each constituent and the standard deviations.
T
SOURCES OF CONTROL
They are either prepared from human serum
or from bovine-based products. Readily available in the market
Commercial Control Sera
Closeness to the true value (test the mean)
Accuracy
Repeatability - pertain to finding the standard deviation
Precision
SOURCES OF ERROR IN ANALYTICAL PHASE
○ Variable to statistical error
○ Inaccuracy
○ analytical errors; caused by some factors in
the analytical system
Systematic error
SOURCES OF ERROR IN ANALYTICAL PHASE
○ Imprecision
○ Personal or operator errors; usually affect only a few analyses
Random errors
POST ANALYTICAL PHASE
- Reporting out of specimen results (manual entries or computer system)
- Physician contact
- Reference ranges
Refers to the sequential events necessary for an infectious disease to spread from one individual to another. It consists of six interconnected links.
Chain of Infection
This is a framework that aims to minimize and control the risks associated with handling biological
agents, such as pathogens in laboratory and healthcare settings.
Hierarchy of Control
COMPREHENSIVE SAFETY PROGRAM
T/F: It addresses biologic hazards by performing Biologic Risk Assessment and the development of safety procedures for working with these hazards
T
COMPREHENSIVE SAFETY PROGRAM
T/F: Describe the safe handling, storage, and disposal of chemicals and radioactive substances
T
COMPREHENSIVE SAFETY PROGRAM
T/F: Clearly outline the laboratory or hospital policies for wrong procedures in the event of fire, natural disasters, and even bomb threats
F; correct procedures
COMPREHENSIVE SAFETY PROGRAM
T/F: Perform initial safety training for all employees in all aspects of laboratory safety and update annually
T
COMPREHENSIVE SAFETY PROGRAM
T/F: Teach correct techniques for lifting and moving heavy objects and patients
T
those substances which singly, or in combination, pose a significant present or potential threat or hazard to human health or to the environment and which singly or in combination require special handling, processing, or disposal
hazardous wastes
CLEAN
C = Contain
L = Leave
E = Emergency
A = Access MSDS or Material Safety Data Sheets
N = Notify supervisor or authorities involved
PROPER WASTE DISPOSAL
general non-recyclable materials, dry
black
PROPER WASTE DISPOSAL
biodegradable, wet
green
PROPER WASTE DISPOSAL
infectious clinical waste
yellow
PROPER WASTE DISPOSAL
radioactive
orange
PROPER WASTE DISPOSAL
infectious clinical wastes
yellow
requires that material safety data sheets (MSDS) be provided for each chemical by manufacturers and suppliers and must be made available on site for laboratory personnel.
Occupational Safety and Health Administration (OSHA) (1970)
MSDS will specifically include:
○ the chemical identity;
○ chemical and common name;
○ physical and chemical characteristics;
○ signs and symptoms of exposure;
○ routes of entry;
○ exposure limits;
○ carcinogenic potential;
○ safe handling procedures;
○ spill cleanup procedures; and
○ emergency first-aid.
RADIATION HAZARD
T/F: Records must be maintained for the length of employment plus 10 years.
F; 30 years
RADIATION HAZARD
can be one of the most toxic sources of exposure to personnel in the lab
Ionizing Radiation
