Clinical Chemistry and Test different types of test of Clinical Chemistry

1. Clinical Chemistry
Name Waqar Ahmad Khan
MPhil Chemistry
Sarhad University Of Science and Technology,Hayatabad,Peshawar,KPK,
Pakistan.

2. Clinical Chemistry Definition
 The The systematic study systematic study of of biochemical
processes biochemical processes associated associated with with
health & disease health & disease & &
 the the measurement of constituents measurement of constituents in
in body fluids or tissues body fluids or tissues to to facilitate facilitate
diagnosis of disease.

3. Scope Of Clinical Chemistry

4. Point-of-care Testing (POCT)
• Also known as Also known as near-patient testing near-patient testing,
, alternate-site alternate-site testing testing or or patient-focused
testing patient-focused testing
• Used in emergency dept., operating suites, clinics, Used in emergency
dept.,operating suites, clinics, health maintenance organization
(HMO), health maintenance organization (HMO), physicians, offices
& nursing homes physicians, offices & nursing homes
• Addresses Addresses acute patient needs acute patient needs
• Instrumentation includes Instrumentation includes portable chemistry
portable chemistry analyzers, glucometers, BG Analyzers, analyzers,
glucometers, BG Analyzers, hemoglobin meters hemoglobin meters &
& coagulation testing

5. Point-of-care Testing (POCT) Continued

6. Laboratory Tests
• Chemical tests
• Chemical tests Direct or Indirect Direct or Indirect Colorimetric
Colorimetric Redox Redox Condensation Condensation
• Degradative tests
• Degradative tests ( ( Enzymatic Enzymatic ) ) One-step or Multi-step
One-step or Multi-step NADH Consumption NADH Consumption
Measurement of Activity .
• Multi-method Multi-method
• Titrimetric Titrimetric
• Electrochemical

7. 1. High thermal resistant glass High thermal resistant glass
• High thermal resistant glass High thermal resistant glass
• Borosilicate glass with low alkali content Borosilicate glass with low alkali
content
• Resists heat, corrosion and thermal shock Resists heat, corrosion and thermal
shock
• Most common are Most common are Pyrex Pyrex, , Kimax Kimax and and Exax
Exax Corex Corex - 6x stronger than borosilicate glass - 6x stronger than
borosilicate glass - - Alumina-silicate glass Alumina-silicate glass - Better able to
resist clouding due to to alkali or scratching - Better able to resist clouding due to
to alkali or scratching - Ideal for - Ideal for higher temperature thermometers,
graduated higher temperature thermometers, graduated cylinders and centrifuge
tubes cylinders and centrifuge tubes. .

8. GLASS: 5 GENERAL TYPES Continued
• Vycor Vycor - - recommended for use in recommended for use in
application involving high application involving high temperature and
drastic heat shock and extreme temperature and drastic heat shock and
extreme chemical treatment with acids and dilute alkalies chemical
treatment with acids and dilute alkalies - heatable to 900 - heatable to
900o oC and withstand downshock from 900 C and withstand
downshock from 900o oC to C to ice water ice water - ideal for - ideal
for ashing and ignition techniques

9. 2.High silica glass
• 96% silica content 96% silica content comparable to comparable to
fused quartz fused quartz in in its its thermal endurance, chemical
stability and thermal endurance, chemical stability and electrical
characteristics electrical characteristics - - radiation resistant, good
optical qualities and radiation resistant, good optical qualities and
temperature capabilities temperature capabilities
• - ideal for - ideal for high precision analytical work high precision
analytical work and can and can also be used for

10. 3. Glass with high resistance to alkalies
• boron-free boron-free glassware for strong alkali solutions glassware
for strong alkali solutions and digestion with strong alkalies and
digestion with strong alkalies
• less thermal resistant than borosilicate glass - less thermal resistant
than borosil.icate glass - known as
• 4. Low actinic glass ; amber or red-colored to reduce the amount of
light passing to reduce the amount of light passing through the
substance within the glassware through the substance within the
glassware - highly protective laboratory glassware for handling -
highly protective laboratory glassware for handling heatheatlabile
substances in the 300-500nm range labile substances in the 300-
500nm range (bilirubin, carotene and vitamin A)

11. PIPETS Two General Types
• PIPETS Two General Types
• 1. 1. Volumetric or Transfer pipet Volumetric or Transfer pipet
• Designed Designed to deliver (TD) a fixed volume of liquid to deliver (TD) a
fixed volume of liquid
• Consists of a Consists of a cylindrical bulb cylindrical bulb joined at both
ends to joined at both ends to narrower glass tubing narrower glass tubing
• Calibration mark is etched around the upper suction tube Calibration mark
is etched around the upper suction tube
• Lower delivery tube is drawn out to a fine tip Lower delivery tube is drawn
out to a fine tip

12. OSTWALD-FOLIN PIPET
• Similar to volumetric pipet but have their bulb Similar to volumetric
pipet but have their bulb closer to the delivery tip closer to the delivery
tip
• Used for Used for measuring viscous fluids as blood or measuring
viscous fluids as blood or serum serum
• Has an Has an etched ring near the mouthpiece etched ring near the
mouthpiece (blowout pipet) (blowout pipet)
• Blown out only when the fluid has drained to Blown out only when
the fluid has drained to the last drop in the delivery tip

13. 2. Graduated or Measuring Pipets
• Plain, narrow tube drawn out to a tip Plain, narrow tube drawn out to a tip
Graduated uniformly along its length Graduated uniformly along its length Two
types which are calibrated for delivery are Two types which are calibrated for
delivery are available available Mohr pipet Mohr pipet
• calibrated between two marks calibrated between two marks on the on the stem
stem
• Serological pipet Serological pipet
• has has graduation marks down on the tip graduation marks down on the tip
• and blown out to deliver the entire volume of and blown out to deliver the entire
volume of the pipet if etched ring or double rings are the pipet if etched ring or
double rings are evident near the mouth of the pipet

14. MICROPIPETS

15. Chemical Hazards

16. SAFETY AGAINST EXPOSURE TO TOXIC
CHEMICALS
• a. Manufacturers of chemicals should evaluate the hazards of evaluate
the hazards of the chemicals the chemicals they produce and they
produce and develop hazard develop hazard communication programs
communication programs for employees exposed to for employees
exposed to hazardous chemicals. hazardous chemicals.
• b. Clinical laboratories should b. Clinical laboratories should develop
and institute a develop and institute a chemical hygiene plan

17. SAFETY AWARENESS FOR CLINICAL
LABORATORY PERSONNEL
• Health Care Organizations focus their responsibility in Health Care
Organizations focus their responsibility in protecting their employees
from infection especially protecting their employees from infection
especially against against hepatitis B virus (HBV), human hepatitis B
virus (HBV), human immunodeficiency virus (HIV) & TB bacilli.
immunodeficiency virus (HIV) & TB bacilli.
• The The Centers for Disease Control (CDC) Centers for Disease
Control (CDC) updated updated the 1983 Guidelines for Isolation
Precautions in the 1983 Guidelines for Isolation Precautions in
hospitals with the release of its Universal Precautions hospitals with
the release of its Universal Precautions in 1987 because of the growing
concern about HIV. in 1987 because of the growing concern about
HIV.

18. BLOOD COLLECTION
• Venipuncture (Phlebotomy) Venipuncture (Phlebotomy)Venous blood is Venous
blood is deoxygenated blood deoxygenated blood that contains that contains
substances that come from metabolic activities of substances that come from
metabolic activities of different organs different organs.Venous blood is mostly
used in analysis of Venous blood is mostly used in analysis of blood blood
chemistry and immunologic studies. chemistry and immunologic studies.Venous
blood is more easily collected than arterial Venous blood is more easily collected
than arterial blood. blood.
• Maybe obtained via Maybe obtained via one-movement one-movement or or two
movement techniques. movement techniques. Sites of venipuncture includes: Sites
of venipuncture includes:Antecubital fossa veins (most preferred site)Antecubital
fossa veins (most preferred site) – median cubital veins and cephalic veins median

19. Arterial puncture
• Arterial blood is Arterial blood is oxygenated blood oxygenated blood.
It is uniform in.It is uniform in composition throughout the body.
composition throughout the body.
• Arterial blood is used to measure Arterial blood is used to measure
oxygen tension, oxygen tension, carbon dioxide tension carbon
dioxide tension and and blood pH. blood pH.
• Blood gas analyses Blood gas analyses (BGA) are critical to patients
(BGA) are critical to patients with with pulmonary problems, oxygen
therapy, pulmonary problems, oxygen therapy, cardiovascular
problems and those undergoing cardiovascular problems and those
undergoing major operations

20. Radial and brachial arteries
• Each site of arterial puncture uses different gauge of Each site of
arterial puncture uses different gauge of needles: needles: Brachial
artery- 18-20 gauge Brachial artery- 18-20 gauge . Radial artery- 23-
25 gauge Radial artery- 23-25 gauge
• In collecting arterial blood, needle is positioned at In collecting
arterial blood, needle is positioned at different angles in each site:
different angles in each site: Brachial artery- 45-60 degrees Brachial
artery- 45-60 degrees Femoral artery- 90 degrees.
• Heparin Heparin is used as anticoagulant for arterial puncture.

21. Complications of arterial puncture
• Hematoma Hematoma due to increased pressure in due to increased
pressure in the artery the artery
• Restriction of blood flow Restriction of blood flow due to reflex due
to reflex constriction constriction ( (arterial spasm arterial spasm) )
• Temporary discomfort Temporary discomfort ( (aching, aching,
throbbing, tenderness, sharp sensation, and throbbing, tenderness,
sharp sensation, and cramping) cramping)
• Thrombosis, hemorrhage and infection Thrombosis, hemorrhage and
infection

22. Skin puncture/Capillary puncture
• Capillary blood is an Capillary blood is an admixture of venous, arterial and
admixture of venous, arterial and capillary blood and may contain tissue fluids
capillary blood and may contain tissue fluids. .
• Skin punctures are suitable in Skin punctures are suitable in pediatric patients,
obese pediatric patients, obese patients with thrombotic tendencies and severe
burns patients with thrombotic tendencies and severe burns. .
• It is It is often preferred to geriatric patients often preferred to geriatric patients
due to due to thinness and less elasticity of skin. thinness and less elasticity of
skin. Sites of skin puncture Sites of skin puncture Infants Infants Lateral plantar
heel surface Lateral plantar heel surface Median plantar heel surface Median
plantar heel surface Children Children Plantar surface of the big toe Plantar
surface of the big toe .