MT 101:

Intro to Med. Lab Science, Laboratory

Safety and Management

Expected Outcomes:
At the end of this unit, students are expected to:
 Comprehend basic ideas about contemporary science and technology;
 Describe the role of science and technology in society; and
 Discuss the importance of science and technology in the field of medicine.

Key concepts:
 Science, technology, society, and medical profession

Science
 (from the Latin word scientia or “knowledge”)
 Is regarded as the heart of technology.
 Main factors behind the invention and development of many products such as computers
and cellphones.
 In academic fields, it has never stopped inspiring and nurturing the minds to think,
discover, and investigate new ideas.

S Systematic an organized body of knowledge derived from a

sound methodology. It can be clearly explained
and consistently applied.

C Conceptual abstract and logical.

I Integrative interdisciplinary, it offers a holistic approach that

includes or uses both classical and modern
concepts.

E Evolving constantly changing. Scientific concepts always

become better and more advance or complex.

N Novel geared towards inventing products that are new

and original.

C Contemporary up to date

E Explanatory a never-ending process of discovery and fact

findings.
Technology
 (from the Greek word tekhnologia or “systematic treatment”)
 Refers to practical application of an organized body of knowledge.
 Based on the results of scientific research, it is intended to provide benefits to people.
 It is “applied science” because it utilizes scientific concepts to produce or create
something which may be in the form of goods, equipment, gadgets, or even techniques.
 Classified into three broad categories: tools, products, and processes.

Tools:
 Various instruments aid medical technologists in performing different laboratory
procedures.
 These instruments may include manually operated devices or a highly sophisticated
automated ones.
 Tools generally speed up the laboratory workflow and therefore reduce turnaround time.
(time from the receipt of the specimen to the release of the result).

Centrifuge:
A centrifuge is a motor-driven machine
that spins an object around a fixed axis. It
operates using the dimentation principle
which states that centripetal acceleration
causes denser substances to separate and
move along a radial direction, eventually
reaching the bottom of the tube, and lighter
substances to remain on top.

Oven:
An oven is a thermostatically controlled
chamber which is used for dry heating.
Ovens in the laboratory utilize the
principle of high-forced volume thermal
convection.

Autoclave:
An autoclave is a device used to sterilize
equipment and culture media by subjecting
them to high-pressure saturated steam at
121 degrees Celsius for 15-20 minutes.
The word autoclave comes from the Greek
word auto, meaning “self” and the Latin
word clavis, meaning “key”. An autoclave
literally means self-locking device.
Microtome:
A microtome is a machine used to cut
uniformly thin slices of tissue blocks,
known as sections. Microtomes use various
types of knives (e.g., steel, alloy steel,
glass, or diamond), depending on the kind
and thickness of the specimen to be sliced.
Water Bath:
A water bath is a water filled vessel used
in laboratories to incubate samples
maintained at a constant temperature

Sphygmomanometer:
A sphygmomanometer is a device used to
measure blood pressure. It consists of a
mercury or mechanical manometer to
indicate the pressure, and a cuff which is
inflatable to temporarily restrict the blood
flow.

Spectrophotometer:
A spectrophotometry is also called a
photometer. It quantitatively measures the
amount of light that a sample absorbs.

Counting Chamber:
A counting chamber is a thick specimen
slide engraved with fine-quality, laser-
etched grids. It is used in counting the
cellular elements of the blood such as red
blood cells, white blood cells, and
platelets.

WBC differential counter

A WBC differential counter is a handy
device used in hematology to manually
count and classify white blood cells.
Sounds are generated each time its keypad
is pressed. The keypad is locked once 100
cells have been counted.
 Pipette:
Pipettes are also called pipets, pippetors, or
chemical droppers. They are tools used to
measure and transfer small volumes of
liquids. Pipettes are designed to have
differing levels of accuracy and precision.
A simple glass-piece pippete, for instance,
is less complex than an adjustable or
electronic one. To manipulate a pippete, a
partial vacuum above the liquid-holding
chamber must be created and carefully
released to draw up and dispense the
liquid.
Incubator:
An incubator is an apparatus used to grow
and maintain microbiological and cell
cultures. The environmental conditions
inside it such as temperature, humidity,
and carbon dioxide and oxygen levels can
be controlled.

Products:
 Various commercial products aid medical technologists when giving routine tests.
 Reagents and kits, for example, are used to carry out specific chemical reactions and
identify analytes of interest.
 Evacuated tubes and plastic bags are used in collecting samples.
 Products such of these are usually supplied by industries to institution such as hospitals,
laboratory schools, and research facilities.
Evacuated blood collection tubes:
Evacuated blood collection tubes are
vacuum-filled tubes used to contain
predetermined volumes of blood
samples. They are available in various
sizes. The tube top is color-coded
according to the type of anticoagulant
and additives loaded in the tubes.
Culture medium:
A culture medium is a liquid or gel
component that supports the growth
of microorganisms such as bacteria,
yeast, or cells. Nutrient agar/broth is
the most common type of culture
medium for non-fastidious
microorganism. Fastidious
microorganism, however, need a
selective or differential culture
medium to grow because of their
complex nutritional requirements.
Staining dyes:
Staining dyes are both natural and
synthetic preparations that impart a
variety of colors to tissues or
microorganisms. They are used to
provide optical differentiation and
contrast in the microscopic images of
cells and tissues.
Syringes:
A syringe is a simple pump consisting
of a plunger fitted tightly in a
cylindrical tube called a barrel. The
plunger can be pushed and pulled
along the interior of the barrel to force
fluid into, or withdraw fluids from,
the body through the opening of the
needle at the opposite end of the
product.
Blood bag:
A blood bag is a sterile medical bag
used in the collection, processing, and
storage of whole blood and blood
components in transfusion. It contains
a pre-measured amount on
anticoagulant and additives such as
citrate, dextrose, phosphate, and
adenine which are needed to sustain
the life of blood cells. A single blood
bag can be attached to various
satellite bags to separate the blood
components in a closed system.
Typing sera:
Typing sera are reagents commonly
used in blood typing. They are
prepared from human or animal
serum and contain antibodies that can
specifically react to one or more
antigens

Capillary tubes:
A capillary tubes is a very thin,
disposable tube used to collect small
amounts of liquid samples by means
of capillary action. It may or may not
contain an anticoagulant. Capillary
tubes are popularly utilized in
laboratory tests requiring only small
amounts of blood samples such as a
micro hematocrit determination.

Urine dipstick:
A urine dipstick is also called a urine
test strip. It is a basic diagnostic tool
used to determine the pathological
changes in a patient’s urine in routine
urinalysis. Urine dipsticks are made
up of plastics strips with absorbent
pads. The pads are impregnated with
substances that can display various
colors and chemically react to the
compounds present in urine.
Rapid diagnostic kits:
Rapid diagnostic kits are
commercially available test kits
which are simple and easy to use. The
test results can be determined
instantly or after a few minutes. A
good example of a rapid diagnostic
kit is an over the counter pregnancy
test kit.
 Tourniquet:
A tourniquet is an elastic bandage
applied to the patient’s extremities to
constrict blood vessels and make the
venipuncture site more prominent
during phlebotomy.

Processes:

 Different routine tests or processes are performed in clinical laboratories by a registered

medical technologists.
 These tests or processes are requested by a physician to aid and support their clinical
diagnosis.

1. Stool examination
 Collection and analysis of fecal specimens to identify the presence or absence of certain
medical condition.
 Fecal occult blood test, microbiological examinations, and chemical test are commonly
perform in a fecal specimen.
 Fecal occult blood test are done to determine if invisible or microscopic blood is present
in the stool. If the result is positive, the physician has to investigate for further source of
bleeding.
 Some conditions engendering fecal occult blood are presence of polyps or cancer
in the colon or rectum.
 Microbiological examinations on the stool aim to find out if bacteria, viruses, and
parasites are present in the stool.
 Chemical test on the stool include fecal pH ( to determine lactose intolerance) and fecal
fat (to detect steatorrhea, a condition characterized by fat malabsorption)
2. Routine urinalysis
 Routine urinalysis is a laboratory test includes the physical , chemical, and microscopic
examination of a urine sample
 Physical examination includes the evaluation of colors, volume, clarity, specific
gravity, and odor.
 Chemical examination of urine analyzes the sample’s pH, protein, glucose,
ketones, blood, bilirubin, urobilinogen, nitrite, and leukocyte esterase.
 Microscopic examination is the final step in urinalysis procedures which entails
the preparation of the urine sediments by means of centrifugation. Quantitation
and identification of the presence of cells , cast, crystals, parasite and other
artifacts are observed.
3. Culture and sensitivity testing
  Culture and sensitivity testing is done in the microbiology section of the laboratory.
 To determine what kind of microorganism may be causing a disease or infection.
 A sample was inoculated into a medium that will grow and support the microorganisms
that might be present in the sample. A series of biochemical tests are performed to
identify the specific microorganism.
 Once identity of the microorganism has been established, sensitivity testing follows.
Sensitivity test was done to determine the best antibiotic that will be effective in
combating the identified causative agent to treat the illnesses or infection.
4. Complete blood count (CBC)
 Is a blood test done in the hematology section of the laboratory.
 Used to assess the overall health status of a patient and detect a wide range of disorders
such as anemia, infection, allergies, and leukemia.
 Panel tests consisting of red blood cell count, white blood cell count, hemoglobin, and
hematocrit determination and wbc differential counts.
 May also report the blood cell indices ( i.e mean corpuscular volume, mean corpuscular
hemoglobin, mean corpuscular hemoglobin concentration, and red blood cell distribution
width) and platelet count.
5. Blood chemistry test
 Are panel test that check the condition and function of the different body organs.
 Test was requested by a physician to evaluate person’s electrolyte balance.
 Serum sample is used to elicit a reaction from the chemical substances present in the
reagents.
 The chemical reaction leads to color changes in the reagents to be measured by means of
a spectrophotometer.
 The concentration of the substance id directly proportional to the intensity of light
generated.
6. Blood typing
 Perform in a blood banking section laboratory, is also referred as blood grouping.
 The primary goal of this laboratory test is to classify a blood sample according to the
presence or absence of antigens inherent in red blood cells.
 Agglutination reaction is interpreted as positive result.
 The correct determination of a blood type is one of the stepping stones to a successful
blood transfusion.
7. Tissue processing
 Comprises the bulk of the work in the histopathology section of the laboratory
 The purpose of tissue processing is to prepare the biopsy or autopsy specimen for the
pathologist’s microscopic examination.
 Tissue processing consists of several distinct steps such as fixation, dehydration, clearing,
infiltration, embedding, trimming, sectioning, staining, mounting, and labelling.
 Ultra-thin slices of tissues are readied for microscopic examinations.
8. Gram staining
 Most important staining technique in differentiating Gram-positive and Gram-negative
one.
 This staining method was developed by a Danish microbiologist named Hans Christian
Gram
  Procedure in 4 simple steps: (1) initial staining with crystal violet of affixed smear of a
bacterial culture; (2) iodine mordanting to increase the affinity of the primary dye; (3)
decolorization by means of alcohol or acetone; and (4) counterstaining with secondary
stain safranin.
 Staining reveal that Gram-positive bacteria are purple, while Gram-negative ones are
either pink or red.
9. Blood collection
 Also called phlebotomy.
 There are several methods of collecting blood namely, skin puncture, venipuncture,
arterial puncture.
 Skin puncture is also called “pricking”.
 Performed when a patient is baby or small amount of blood is needed.
 Blood is collected through a skin puncture in the finger, toe, heel, or earlobe.
 Capillary blood is obtained in this method of blood collection.
 Venipuncture is the process of withdrawing venous blood sample from the veins.
 The site of choice is the median cubital vein of the antecubital fossa.
 Done if several test procedures will be performed.
 Arterial puncture is performed when blood gas analysis is needed to investigate acid –
base balance.
 Blood sample is directly obtained from the radial, brachial or femoral artery.
10. Rapid diagnostic testing (RDT)
 A medical test performed to aid in the diagnosis or detection of the disease.
 The procedure employed in this type of test is simple and easy to perform.
 Result is available in shorter turnaround time.
 Frequently employs immunochromatographic principles using handy and portable test
kits in plastic strips or cassettes.

REY A. LOVENDINO, RMT, MSPH

Associate Professor
CY 2024-2025