2. PH
electrode
• The hydrogen ion concentration or pH is a
measure of the acidity or alkalinity of a
solution.
• PH = 1
log 10 (H+)
• (H+) is the hydrogen ion concentration of the
solution in moles per liter.
3. • In an aqueous solution, the product of
hydrogen ion concentration and hydroxyl ion
concentration is constant.
• At a temperature of 22, this product
conveniently happens to be exactly 10-14
(expressed in gramme-molrcules per liter).
• The pH of solution is defined as the negative
logarithm of the hydrogen ion concentration,
in an aqueous solution.
4. • The value of using pH can be seen in the case
of human blood which has an extremely low
hydrogen ion concentration.
Blood H+
Blood pH
= 0.398x10-7
= -log (0.398 x 10-7)
= 7.4
5. Principle:
When the pair of electrodes or a combined
electrode (glass electrode and calomel
electrode) is dipped in an aqueous soln, a
potential is developed across the thin glass of
the bulb (of glasss electrode).
The e. m. f. of complete cell (E) formed by the
linking of these two electrodes at a given soln
temp. is therefore
6. E = Eref-Eglass
Eref is the potential of the stable calomel electrode
which at normal room temp. is +0.250V.
Eglass is the potential of the glass electrode which
depends on the pH of the soln. under test.
The resultant e.m.f. can be recorded
potentiometrically by using vacuum tube amplifier.
Variations of pH with E may be recorded directly on
the potentiometer scale graduated to read pH
7. Important Components of pH
Meter
1. Glass electrode
2.Calomel electrode
3.Electrometer
1.Glass Electrode:
It consists of a very thin bulb about 0.1 mm thick
blown on to a hard glass tube of high resistance.
The bulb contains 0.1 mol/litre HCL connected to
a platinum wire via a silver-silver chloride
combination.
8. 2.Calomel electrode:
It consists of a glass tube containing saturated
KCl connected to a platinum wires through
mercury-mercurous chloride paste.
3.Electrometer:
Which is a device capable of measuring very
small differences in electrical potentials in a
circuit of extremely high resistance.
10. Working Mechanism
• An acidic solution has far more positively charged
hydrogen ions than an alkaline one, so it has
greater potential to produce an electric current in a
certain situation.
• In other words, it is a bit like a battery that can
produce a greater voltage.
• A pH meter takes advantage of this and works
like a voltmeter: it measures the voltage
(electrical potential) produced by the solution.
11. Contd…
• When two electrodes (or one probe containing the
two electrodes) are dipped into solution, some of the
hydrogen ions in the solution move toward the glass
electrode and replace some of the metal ions in its
special glass coating.
• This creates a tiny voltage across the glass the silver
electrode picks up and passes to the voltmeter.
• Reference electrode acts as a baseline or reference
for the measurement.
12. Contd…
• A voltmeter measures the voltage generated by
the solution and displays it as a pH-measurement.
• An increase in voltage means more hydrogen ions
and an increase in acidity, so the meter shows it as
a decrease in pH; in the same way, a decrease in
voltage means fewer hydrogen ions, more
hydroxide ions, a decrease in acidity, an increase in
alkalinity, and an increase in pH.
↑ voltage = more H+/less OH- = ↑ acidity = ↓pH
↓ voltage = less H+/more OH- = ↓ acidity = ↑pH
13. Glass Membrane Electrode
• Advantages of glass electrode:
It can be used in presence of oxidizing, reducing,complexing
• Disadvantage:
1. Delicate, it can’t be used in presence of dehydrating agent e.g.conc.
H2SO4, ethyl alcohol….
2. Interference from Na+ occurs above pH 12 i.e Na+ excghange
together with H+ above pH 12 and higher results areobtained.
3. It takes certain time to come to equilibrium due to resistanceof
glass to electricity.
14. Gas- sensing electrodes
Two gas electrodes are widely used in biology
1. The oxygen electrode
2. The carbon dioxide electrode
O2 electrode is used in many diverse
branches of biology
CO2 electrode is chiefly used to measure CO2
in the blood.
15. 1. Oxygen electrode (pO2)
• It is used in many diverse branches ofbiology
• Different anode- cathode combinations for oxygen
electrode are available, the platinum with silver/silver
chloride is the most used cathode-anode combination.
• Arrangement of these electrodes is annular withthe
anode enclosing the platinumcathode.
• Electrodes dip into an electrolyte soln. (usually
buffered KCl soln.) which is held inside an electrodeby
an oxygen permeable membrane.
• Membrane might be a very thin polypropylene.
• Polarization of electrodes at 0.6v is achieved withthe
help of a mercury cell.
17. Mechanism of Oxygen (pO2) Electrode
When the oxygen electrode is dipped into
a solution containing oxygen, the following
reactions happen:
i. The oxygen molecules from the sample diffuse
through the membrane into the electrolyte
so that within a short time the electrolyte
and the sample come to equilibrium with
respect to the pO2 .
18. Contd…
ii. The outermost valency shell of each oxygen atom
has a vacancy for two electrons upon acceptance
of which it can be turned into an oxygen ion.
These electrons are supplied by the platinum
cathode. The reaction at the cathodeis:
4e- +O2 + 2H2O =4OH-
iii.The hydroxyl ions so produced at the cathode
then react with KCl in the electrolyte soln. The
reaction in the electrolyteis:
OH- + KCl = KOH + Cl-
19. Contd…
iv.The negatively charged chloride ion produced in
the electrolyte soln. are attracted to the positive
anode and donate their electrons. The reaction at
the anode is:
Cl- = Cl + e-
Ag + Cl = AgCl
Thus, deposition of AgCl on to the anode.
v. The current through the system is directly
proportional to the pO2 and can be recorded
directly after amplification into pO2.
20. 2. Carbon dioxide electrode (pCO2)
• It is used to measure carbon dioxide in the
blood.
• Constituents of a carbon dioxide electrodes
are
A conventional glass PH electrode with a
calomel reference electrode.
A thin plastic or teflon membrane which is
permeable to carbon dioxide and not to other
ions.
21. Contd…
A standard bicarbonate solution, usually 0.005M
NaHCO3 between the membrane and the glass
electrode.
• When the electrode is dipped into a sample
containing dissolved CO2 , the CO2 is allowed to
diffuse into the bicarbonate solution by the
permeable membrane.
22. Contd…
• The PH of the bicarbonate solution changes,
and this change is read by the glass electrode.
• This pH change is reflected by the pH meter
which is directly calibrated for pCO2.
• The response time of a CO2 electrode is
higher because the standard bicarbonate soln.
has to come into equilibrium with the sample.
23.
24. Mechanism of Carbon dioxide
(pC02) Electrode
It contains pH sensitive glass electrode and a
reference electrode immersed in a bicarbonate
buffer system.
This is separated from the solution under test
(mainly blood) by a plastic membrane permeable
to gaseous CO2, but not permeable to dissolved
ions.
The CO2 in blood diffuses through the plastic
membrane and reacts with the buffer system to
change the pH.
25. Contd…
The pCO2, electrode takes advantage of the fact
that pH has a linear relationship to the log pCO2
over the range of 10-90 mmHg.
The H+ ion conc. Change due to the dissolution of
CO2 is detected by the pH-sensitive glass electrode.
A potential difference exists betn the glass
electrode & reference electrode and it is
measured on the meter.
The meter’s scale is usually calibrated for pCO2 in
a semi logarithmic fashion, since PH is inversely
proportional to the log of the pCO2.
26. Applications gas-sensing electrodes
The O2 electrode is being widely used in many
different biological experiments wherever
there is a need of measuring oxygen.
The CO2 electrode on the other hand is
mainly used for clinical purposes, often for
measuring the CO2 in blood orplasma.
27. MEASUREMENT OF PHCO3
• Blood gas analyzers are used to measure the content of pH,
pCO and PO2 from the blood
• Two gases of accurately known O2 and CO2 percentages are
required for calibrating the analyzer in pO2 and pCO2 modes.
These gases are used with precision regulators for flow and
pressure control.
• Two standard buffers of known pH are required for calibration
of the analyzer in the pH mode
• Input signal to the calculator is obtained from the outputs of the
pH and pCO2 amplifiers
28. Contd.,
• The outputs are adjusted by multiplying with a
constant and are given to an adder circuit
• The output of adder is passed to antilog
generators circuit. Then it is passed to A/D
converter for display. Resistance R is used to
adjust zero at the output.
• Total CO2 is calculated by summing the output
signals of the calculators and the output of the
pCO2 amplifier
30. biomolecules in solution
ss the mixture.
• Electro- Kinetic Energy
• Columbs Law: Electrical Field E=f/q f- Columbs Force q-
Charge
• Technique used to separate different molecules based on
charge, shape, and size.
• Protein and DNA molecules
• Electrophoresis is used: for analysis and purification of very
large molecules (proteins, nucleic acids)
for analysis of simpler charged molecules (sugars, amino
acids, peptides, nucleotides, and simpler ions).
• It is the process of moving charged
by applying an electrical field acro
DNA is -ve Charge
Protein can be - -ve or +ve charge
Basic Principles of electrophoresis
31. When charged molecules are
placed in an electric field, they
migrate toward either the
positive (anode) or negative
(cathode) pole according to
their charge.
1. Factors influenced
electrophoresis mobility:
2. Net charge of the molecule
3. size and shape
4. concentration of the molecule
in solution
32. Types of Electrophoresis
1. Zone Electrophoresis – Movement of ions is within
a area without interaction with surrounding
molecules
• Paper Electrophoresis
• Gel Electrophoresis – Mostly used
• Thin layer Electrophoresis
• Cellulose acetate Electrophoresis
2. Moving Boundary Electrophoresis - Movement of
ions with interaction with surrounding molecules
• Capillary Electrophoresis
• Isotachophoresis
• Isoelectric Focussing
• Immuno Electrophoresis
33. GEL Electrophoresis
GEL - Agarose – highly purified
polysaccharide derived sugar
polymers held together by
hydrogen and hydrophobic bonds.
Polyacrylamide gels
Polyacrylamide gel structure held
together by covalent cross-links
• During electrophoresis,
macromolecules are forced to
move through the pores when
the electrical current is applied.
34. Power
DNA
H
O2
When placed in an electrical field, DNA will migrate toward thepositive
pole (anode).
An agarose gel is used to slow the movement of DNA and separate bysize.
Polymerized agarose is porous,
allowing for the movement of DNA
Scanning Electron Micrograph
of Agarose Gel (1×1µm)
35. • Function of buffer
1. carries the applied current
2. established the pH
3. determine the electric charge on the solute
• High ionic strength of buffer
– produce sharper band
– produce more heat
• Commonly used buffer
• Barbital buffer & Tris-EDTA for protein
• Tris-acetate-EDTA & Tris-borate-EDTA (50mmol/L; pH 7.5-7.8)
Buffers
36. Cellulose Acetate Electrophoresis
Cellulose acetate strip is saturated with the buffer solution and
placed in the membrane holder. It is otherwise known as
bridge.
The two ends of the bridge are placed in the cuvette in which
buffer solution is available.
The sample for each test is placed on the strip at a marked
location. Then, the constant electric potential(250 V) is applied
across the strip 4 – 6 mA of initial current is obtained.
After 15-20mins, the electric voltage is removed, then,
migrated protein band is stained with buffer and it is dried in
preparation for densitometry.
38. Photometer & Colorimeters
Measure blood protein and iron level by their absorption of light.
Principle: analyzing the transmitted light through the sample or
emitted light by the sample the concentration of substances is
measured.
Transmittance T = I1 /I0 (Transmitted light intensity/ Incident
light intensity )
Absorbance or optical density A= - log(I1 /I0 )
A= CL ( C- Concentration of absorbing substance, L- path length
of cuvette).
Filter Photometer- Filter is used to select specific wavelength.
Spectrophotometer- Diffration grating or prism is used as
Monochromator to get spectral wavelength.
39. How colorimeter works?
1- White light from a tungsten lamp passes through a slit,
then a condenser lens, to give a parallel beam which falls
on the solution under investigation contained in an
absorption cell or cuvette. The cell is made of glass with
the sides facing the beam cut parallel to each other.
Light source slit cuvette filter photocell galvanometer
condenser
lens
40. How colorimeter works?
2- Beyond the absorption cell is the filter, which is
selected to allow maximum transmission of the color
absorbed. If a blue solution is under examination, then
red is absorbed and a red filter is selected.
•NOTE: The color of the filter is complementary to the
solution.
Light source slit cuvette filter photocell galvanometer
condenser
lens
41. How colorimeter works?
3- The light then falls on to a photocell which
generates an electrical current in direct proportion to
the intensity of light
Light source slit cuvette filter photocell galvanometer
condenser
lens
42. Filter photometer
Sample S concentration is determined the adjustment
required for galvanometer G to have null deflection.
Filter – Colored glass/ gelatin paper/ colored
solution.
Photo detector- Photo voltage cell / photo emissive
cell
43. The Spectrophotometer:
•Is a sophisticated type of
colorimeter where monochromatic
light is provided by prism.
•The band with of the light passed by
a filter is quite board, so that it may
be difficult to distinguish between
two components of closely related
absorption with a colorimeter. A
spectrophotometer is then needed.
•Two types – Single beam and
double beam spectrophotometer.
44.
45. Flame photometer
Potassium(k), sodium(Na),
calcium(Ca) and Lithium(Li)
K- 4047Å(violet)
Na- 5890Å(yellow)
Li- 6708Å(Red) – used as
reference and added in sample.
Acetylene is added in air.
Intensity of light is adjusted by
flow rate of air or changes in the
flow of fuel gas.
46. Purpose of Autoanalyzers
An autoanalyzer sequentially measures blood
chemistry through a series of steps of
mixing,
reagent reaction and
colorimetric measurements.
47. Principle of operation
A stream of material is divided by air bubbles into
discrete segments in which chemical reactions occur.
An essential principle of the system is the introduction of air bubbles.
The air bubbles segment each sample into discrete packets and act as a barrier
between packets to prevent cross contamination as they travel down the lengthof
the tubing
The continuous stream of liquid samples and reagents
are combined and transported in tubing and mixing
coils.
The tubing passes the samples from one apparatus to
the other each apparatus performs different
function, such as distillation, dialysis, extraction, …,
and subsequent recording of a signal.
48. Principle of operation
In Segmented Flow Analyzers (SFA), the sample is
mixed with small reproducible volumes of the required
reagents
air bubbles are introduced into the flow, creating
about 20 - 100 segments of liquid for each sample
The sample / reagent mixture flows through mixing
coils (heated coils) a color proportional to the
amount of analyte in each sample is developed
The samples with developed color flow through a
colorimeter to measure the color
49. It consists of
Sampler:
Aspirates samples, standards, wash solutions into the system
Proportioning pump:
Mixes samples with the reagents so that proper chemical color
reactions can take place, which are then read by the colorimeter
Dialyzer:
The purpose of a dialyzer is to separate the analyte from interfering
substances such as protein, whose large molecules do not go through
the dialysis membrane but go to a separate waste stream
The analyte infuses through the diaphragm into a separate flow path
going on to further analysis
50. It consists of
Heating bath:
Controls temperature (typically at 37 °C), as temp is critical in color
development
Colorimeter:
Monitors the changes in optical density of the fluid stream flowing
through a tubular flow cell. Color intensities proportional to the
substance concentrations are converted to equivalent electrical voltages
(Pulses,square wave signal)
Recorder:
Displays the output information in a graphical form.
52. Blood Flow meter
Electromagnetic blood flow meter
Ultrasonic blood flow meter
• Transit time principle
• Doppler principle
• Continuous and pulsed
Laser based Doppler blood flow meter
NMR blood flow meter
53. 1.Electromagnetic Blood Flow Meters
• Measures instantaneous pulsatile flow of blood
• Works based on the principle of electromagnetic
induction
• The voltage induced in a conductor moving in a magnetic
field is proportional to the velocity of the conductor
• The conductive blood is the moving conductor
54.
55. Principle of Electromagnetic Blood Flow Meters
• A permanent magnet or electromagnet
positioned around the blood vessel
generates a magnetic field perpendicular to
the direction of the flow of the blood.
• Voltage induced in the moving blood column
is measured with stationary electrodes
located on opposite sides of the blood vessel
and perpendicular to the direction of the
magnetic field.
56. Principle of Electromagnetic Blood Flow Meters
• This method requires that the blood vessel
be exposed so that the flow head or the
measuring probe can be put across it.
57. Types of Electromagnetic Blood Flow
Meters
• DC Flow meters
• Use DC Magnetic field.
• Cause electrode polarization and amplifier drift.
• AC Flow meters
• Electromagnets are driven by alternating
currents.
• The transducer acts like a Transformer and
induces error voltages that often exceed the
signal levels by several orders of magnitude.
58. BME 312-BMI II-L3-ALİ IŞIN
2015
2. Ultrasonic Blood Flow Meters
• A beam of ultrasonic energy is used to
measure the velocity of flowing blood.
• Two types:
• Transit time flow meters
• Doppler type.
60. Transit-Time Ultrasonic Flow Meters
• Where
• t - transit time
• D - Distance between the transducers
• c - Sound velocity
• u - blood flow velocity
61. Ultrasonic flow meter- Transit
• The pulsed beam is
directed through a blood
vessel at a shallow angle
and its transit time is
measured.
• The transit time is
shortened when the
blood flows in the same
direction as the
transmitted energy
• The transit time is
lengthened otherwise.
62. Doppler type Ultrasonic Flow Meters
• Based on the Doppler principle
• A transducer sends an ultrasonic beam with a frequency F
into the flowing blood.
• A small part of the transmitted energy is scattered back
and is received by a second transducer arranged opposite
the first one.
• The reflected signal has adifferent frequency F + FD or F
– FD due to Doppler effect.
63. Doppler Frequency equation
• Where
• fd = Doppler frequency shift
• f0 = source frequency
• u = target velocity
• c = velocity of sound
64. Doppler type Ultrasonic Flow
Meters…
• The Doppler component FD is directly proportional to the velocity
of the flowing blood.
• A fraction of the transmitted ultrasonic energy reaches the second
transducer directly with the frequency being unchanged.
66. CW- Doppler type
• After amplification
composite
Doppler frequency can
of the
signal, the
be
obtained at the output of
the detector
difference between
as the
the
direct and the scattered
signal components.
• For normal blood velocities,
the Doppler signal is
typically in the low audio
frequency range.
67. Fetal Heart measurement
• Acoustic coupling
• Placed in heart or umbilical
cord
• 10 to 12th week
• Thump, thump- Low
frequency, rapid rhythm- fetal
heart movement
– umbilical
– High Freq, rapid
cord
• Swish
rhythm
sound
• Thuuummp- low, slow-
mother movement
• Woooch- mid freq, slow-
mother arteries
70. Indicator Dilution Methods (1)
Dye Dilution Method
A bolus of indicator, a colored dye (indocyanine green), is rapidly injected in
to the vessel. The concentration is measured in the downstream
The blood is drawn through a colorimetric cuvette
and the concentration is measured using the
principle of absorption photometry
m
t
Ctdt
F
1
0
amount of
dye
1% peak C
Avg.
flow
71. Q
t
b
b b T t dt
F
1
0
c
Indicator Dilution Methods (2)
Thermal Dilution Method
A bolus of chilled saline solution is
injected into the blood circulation system
(right atrium). This causes decrease in the
pulmonary artery temperature.
heat content
of injectate
An artery puncture is not needed in this technique
Several measurements can be done in relatively short time
A standard technique for measuring cardiac output in critically ill patients
density of blood
(e.g. 1060 kg/m3)
specific heat of blood
(e.g. 3640 J/(kg*K)
72. Photoelectric Method
A beam of IR-light is directed to the
part of the tissue which is to be
measured for blood flow (e.g. a finger
or ear lobe)
The blood flow modulates the attenuated
/ reflected light which is recorded.
The light that is transmitted / reflected is
collected with a photodetector
Poor measure for changes in volume
Very sensitive to motion artefacts
Method is simple
Heart rate is clearly seen
74. Radioisotopes
A rapidly diffusing, inert radioisotope of lipid-soluble gas (133Xe or 85 Kr) is
injected into the tissue or passively diffused
The elimination of the radioisotope from microcirculatory bed is related to
the blood flow:
C(t) C0 exp kt
k ln2/t1/ 2
75. Thermal Convection Probe
The method is not very common due extreme nonlinear properties and difficulties
in practical use (e.g. variable thermal characteristics of skin)
This is one of the earliest techniques for blood flow measurements
The rate of heat removal from the tissue under probe is measured
The concentric rings are
isolated thermally & electrically
from each other
The central disk is heated
1 – 2o C over thetemperature
of tissue
A temperature difference of
2- 3 o
C is established between
the disks
76. Cardiac output and Measurement of
Flow & Volume of blood
A measurement of paramount importance: concentration
of O2 and other nutrients in cells Very difficult to
measure
Second-class measurement: blood flow and changes in blood volume correlate well
with concentration
Third-class measurement: blood pressure correlates well with blood flow
Fourth class measurement: ECG correlates adequately with blood pressure
How to make blood flow / volume measurements?
Standard flow meters, such as turbine flow meters,
obviously cannot be used!
Indicator-dilution method: cont./rapid injection, dye dilution, thermodilution
Electromagnetic flowmeters
Ultrasonic flowmeters / Doppler flowmeters
Plethysmography: Chamber / electric impedance / photoplethysmography
77. Indicator Dilution with Continuous
Injection
Measures flow / cardiac output averaged over several heart
beats
dt C
dm dt
Ca Cv
Fick’s technique: the amount of a substance (O2) taken up by an organ / whole body
per unit time is equal to the arterial level of O2 minus the venous level of O2 times the
blood flow
F
dV
dm dt
Blood flow, liters/min
(cardiac output)
Consumption of O2 (mL/min)
Arterial and venous
concentration of O2 (mL/L of blood)
dV dt
C
dm dt
Change in [] due to
continuously added
indicator m to volume V
79. Dye Dilution
In dye-dilution, a commonly used dye is indocyanine
green (cardiogreen), which satisfies the following
Inert
Safe
Measurable though spectrometry
Economical
Absorption peak is 805 nm, a wavelength at which absorption of blood is
independent of oxygenation
50%of the dye is excreted by the kidneys in 10 minutes, so repeat measurements is
possible
80. Thermodilution
The indicator is cold – saline, injected into the right
atrium using a catheter
Temperature change in the blood is measured in the
pulmonary artery using a thermistor
The temperature change is inversely proportional to
the amount of blood flowing through the pulmonary
artery
81. Measuring Cardiac
Output
Several methods of measuring cardiac output In the Fick method, the indicator is O2; consumption
is measured by a spirometer. The arterial-venous concentration difference is measure by drawing
simples through catheters placed in an artery and in the pulmonary artery. In the dye-dilution
method, dye is injected into the pulmonary artery and samples are taken from an artery. In the
thermodilution method, cold saline is injected into the right atrium and temperature is measured in
the pulmonary artery.
82. Respiratory Measurement
Respiratory Volumes
Used to assess a person’s respiratory status
• Tidal volume (TV)
• Inspiratory reserve volume (IRV)
• Expiratory reserve volume (ERV)
• Residual volume (RV)
84. Respiratory
capacities
Functional residual
capacity (FRC)
Volume of air remaining in
the lungs after a normal tidal
volume expiration:
FRC = ERV + RV
Maximum amount of air
contained in lungs after a
maximum inspiratory effort:
TLC = TV + IRV + ERV + RV
Maximum amount of air that
can be expired after a maxi-
mum inspiratory effort:
VC = TV + IRV + ERV
Maximum amount of air that
can be inspired after a normal
expiration: IC = TV + IRV
Total lung
capacity (TLC)
Vital capacity
(VC)
Inspiratory
capacity (IC)
85. Three types of Pulmonary Measurements
1. Ventilation
– Determines the ability of body to displace air volume
quantitatively and speed with which the air moves
– Spirometer
2. Distribution
– Indicates the degree of lung obstructions for air flow and
determines the residual air volume.
– Pneumotachometer
3. Diffusion
– Lung ability to exchange gas or rate of gas exchange with
circulatory system
– Gas Analysers
86. Spirometer
•Measure respiratory volumes and
capacities
• Obstructive pulmonary disease
—increased airway resistance
(e.g., bronchitis)
•Restrictive disorders—reduction in total
lung capacity due to structural or functional
lung changes (e.g., fibrosis or TB)
• Light weight bellows ( no airway resistance error)
• Biased potentiometer , its wiper arm voltage is proportional to volume VOL.
• VOL max = Lπ r2
•VOL = (Vout/ VBB) VOL max
87.
88. Gas Analysers
Quantitative composition of inspired and expired
gas.
Infrared absorption of Co2, Paramagnetic behavior of
O2, Thermal conductivity of Co2.
Infrared Gas Analyzers
Paramagnetic oxygen analyzer
Thermal conductivity Gas Analyzers
89. Infrared Gas analyser
Co2 Absorption of Infrared is used.
Infrared source temperature - 815 ̊c,
peak wavelength -3µm.
Sampler is a microcatheter cell draws
0.1 ml gas
Detector with transparent infrared
window separated by thin flexible
metal diaphragm.
Capacitance detector replaced by
solid state detector like lead
selenide(PbSe).
90. Paramagnetic oxygen analyzer
• O2 has two unpaired
electronics , attracts magnetic
lines of force.
• Nitric oxide/ nitrogen dioxide
has, but small than O2.
• Dumb bell is suspended with
Platinum iridium thread.
• O2 gas flows, replaces
diamagnetic dumb bell and
mirror rotates and deflects light
over the scale.
91. Thermal Conductivity gas analyzer
• Difference in thermal conductivity of
gases is used to determine quantitative
composition of gas mixtures.
• 4 platinum filaments as heat sensing
element.
• R1 & R2 reference gas arms S1 & S2
sample gas arms.
• Through Reference gas, the bridge is
balanced
• O2 and CO2 thermal conductivity varies,
so ions of CO2 is easy.
• O2 and NO2 is also same, so not used to
measure using this.
94. glass tube filled with liquid (often mercury or
alcohol) that expands/contracts
95. A gas thermometer measures
temperature by the variation in volume
or pressure of a gas
It has width range (2500C - 15000C)
This thermometer makes use
of a bimetallic strip that
consists of two strips of
different metal joined together.
As temperature increases, the
coiled bimetallic strip bends
more to rotate a pointer
around on a scale.
96. Wires made of two different metals are joined
together to form two junctions.
It is very sensitive and can measure a wide
range of temperatures.
It is commonly used in industry to measure the
temperatures of ovens and furnaces
97. Thermometer that measures
temperature by changes in the
resistance of a spiral of platinum wire
An instrument for measuring high
temperatures (over 60000C)
It used to measure thermal
radiation
96
98. Pulse
The pulse is the number of heartbeats per minute.
The pulse can be measured at the:
Back of the knees
Groin
Neck
Temple
Top or inner side of the foot
Wrist
Once you find the pulse, count the beats for 1 full minute. Or count the beats for
30 seconds and multiply by 2. This will give the beats per minute.
97
99. Pulse (cont.)
Regular Pulse Rhythm
Count for 30 seconds,
then multiply by 2
(a rate of 35 beats in 30
seconds equals a pulse
rate of 70 beats/minute)
Irregular Pulse Rhythm
Count for one full minute
May use stethoscope to
listen for apical pulse and
count for a full minute
100. Pulse Measurement
Pulse – number of times the heart beats in
1 minute
Respiration – number of times a patient breaths in 1
minute
One breath = one inhalation and one exhalation
Ratio of pulse to respirations is 4:1
101. Why Pulse Measurement
Measuring the pulse gives important information about our health.
To see how well the heart is working.
Help find the cause of symptoms, such as an irregular or rapid
heartbeat (palpitations), dizziness, fainting, chest pain, or shortness
of breath.
During or immediately after exercise, the pulse rate gives
information about your fitness level and health.
Check for blood flow after an injury or when a blood vessel may
be blocked.
102. Pulse Rate
Newborns 0 - 1 month old:
Infants 1 - 11 months old:
Children 1 - 2 years old:
Children 3 - 4 years old:
Children 5 - 6 years old:
Children 7 - 9 years old:
70 - 190 beats per minute
80 - 160 beats per minute
80 - 130 beats per minute
80 - 120 beats per minute
75 - 115 beats per minute
70 - 110 beats per minute
Children 10 years and older, and adults (including seniors): 60 -
100 beats per minute
Well-trained athletes: 40 - 60 beats per minute
103. Blood Cells - Introduction
A. Red Blood Cells
1. Red blood cells (erythrocytes) are biconcave
disks that contain one-third oxygen-carrying
hemoglobin by volume.
2. When oxygen combines with hemoglobin bright red
oxyhemoglobin results.
3. Deoxygenated blood (deoxyhemoglobin) is darker.
4. Red blood cells discard their nuclei during development
and so cannot reproduce or produce proteins.
5. The number of red blood cells is a measure of the blood's
oxygen-carrying capacity.
104. • Red Blood Cell Counts
4,600,000-6,2000,000 cells per mm3 - Male
4,200,000-5,400,000 cells per mm3 – Females
• Red Blood Cell Production and Its Control
Embryo and fetus, red blood cell - yolk sac,
liver, and spleen; after birth, in the
red bone marrow.
The average life span of a red blood cell
is 120 days.
105. C. Red Blood Cell Production and Its Control
1. In the embryo and fetus, red blood cell
production occurs in the yolk sac, liver,
and spleen; after birth, it occurs in the
red bone marrow.
2. The average life span of a red blood cell
is 120 days.
CopyrightThe McGraw-Hill Companies, Inc. Permission required for reproduction or display.
106. White Blood Cells
• White blood cells (leukocytes) help defend the
body against disease.
• They are formed from hemocytoblasts
(hematopoietic stem cells).
Blood Platelets
• Blood platelets are fragments of megakaryocytes.
• Platelets help repair damaged blood vessels by
adhering to their broken edges.
• Normal counts vary from 130,000 to 360,000
platelets per mm3.
107. Diseases of the Blood
Cell Type Increase count Decrease count
WBC Infectious diseases
Inflammatory disease
Severe emotional
Physical stress
Tissue damage
Bone marrow failure
Presence of toxic substance
Disease of the liver/spleen
Radiation
RBC Renal tumor
Iron overload in organs
Anemia
Chronic inflammation
Platelet Renal disease
Infection or inflammation
Anemia
Bone marrow failure
Uremia
Liver disease
108. Blood cell type Sizes
(um)
Normal Ranges
(per mm3)
-- -- Male Female
Red blood cell 6-10 4.5-6.5 M 3.9-5.6 M
White blood cell 10-20 4.5-11 k 4.5-11k
Platelets 2-4 150-350 k 150-350 k
Blood cell sizes and their normal
ranges
