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Ministry of Higher Education and
Scientific Research
Foundation Of Technical Education
Technical Medical Institute
Training package (1 + 2 )
In
TERMINOLOGY and MODELING
For Students /
First Class of Anesthesia
Department
By :
Dr. IKBAL ABDULHAMED
Dec/2009
Ministry of Higher Education and
Scientific Research
Foundation Of Technical Education
Technical Medical Institute
Training package ( 3 + 4 )
In
Forces on and in the body
For Students /
First Class of Anesthesia
Department
By :
Dr. IKBAL ABDULHAME
Dec/2009
1 / OVER VIEW
1 /A- Target Population :
This Directed To Class One Students In
Anesthesia Department Of Technical Medical
Institute.
1 / B – Rationale :
This lecture give the students the knowledge about
the forces on and in the body and the pyysics of
skeleton .
1 / C – central idea
The central idea includes :
1-know what we mean by forces on and in the body
2-types of theses forces
3-the levers
4- physics of skeleton
5-effect of acceleration
1 / D – instructions
1-study the over view very well
2-identify the aims of forces on and in the body
and the physics of the skeleton .
3- do the pre test , if you got
a- five degree and more so you don’t need to study
the subject then consult the instructor
b-less then 5 degree so you need to study the
subject and continue in your studying …
4- after your studying to these subject content do
the post test , if you got :a- five and more then pass to study the second
lecture
b-less than five degree then go back to study the
first lecture or any part of it then do the post test
again.
2/ performance Objectives
After studying the second lecture the student will
be able to
1- know the definition of force and its types in and
on the body
2- forces on the body (static , frictional, dynamic )
3- forces in the body (gravitational , electrical ,
nuclear )
4-levers (the muscle and bone system act as a lever
)
5- physics of the skeleton ( functions of bones of
the skeleton )
6-effect of acceleration.
3/ pre test
Put circle around the letter of the correct answer
1- forces on the body include all except :
a: nuclear forces
b: frictional forces
c: dynamic forces
d: static forces
2- - forces in the body include :
a: nuclear force
b: frictional force
c: dynamic force
d: static force
3- the head represent levers of the
a- first type
b-second type
c- third type
d-none of above
4-elbow joint represents the typer of
a-first levers
b-second levers
c-third levers
d-none of above
5-distortion pf elastic tissue of the body is due to
a- effect of forces
b-effect of mass
c-effect of gravitation
d-effect of acceleration
NOTE: 1 degree for each answer
Check your answer in key answer page at the end
of the lecture
The subject content
Forces on and in the body
 Forces in the body are :1-Gravitational forces
2- Electrical forces
3-Nuclear force
 Forces on the body :1-Statis forces
2-Frictional forces
3-Dynamic forces
Forces in the body
1-Gravitational forces Newton formulated the law of
universal gravitation . this law states that “ there is a
force of attraction between any two objects “ for
example our weight is due to attraction between the
earth and our bodies
Note :gravitational force is very small in the moon
because the attraction between the moon and the body is
small .
Effect
of gravitational force
1- The formation of varicose veins in the leg this
happens because of the attraction of the earth to the
blood . this attraction resist the flow up of the blood
For example: the venous blood travels against th force of
gravity on its way to the heart .
2- The lose of some minerals of the bone when a person
becomes weightless (such as in an orbiting satellite) ,
then some of the bone mineral is lost .
This effect happens even t=in the present of gravity (such
as the case in which the person is in long term bed rest)
.this case will cause the removal of much of the force of
body weight from the bone and can lead to seriouse bone
mineral loss
2- Electrical forces
This force is more complicated than gravity since it
involves attraction and repulsive forces between static
electrical charges as well as magnetic forces produced by
moving electrical charges .
 Electrical force are immense compared to gravitational
force , for example: the electrical forces between an
electron and a proton in a hydrogen atom is about (
10*34 times ) greater than the gravitational forces
between them
** Electrical current : it’s a moving electrical
charges or it’s a moving electrons
** The forces that are produced by the muscle are
caused by electrical charges attracting or repelling
other electrical charges
Types of electrical forces :
1- Static forces : either attraction or repulsive forces
between static electrical charges .
2- Magnetic forces : which are produced by the
moving electrical charges in the muscles and nerves .
3- Nuclear forces : which keep the positive charges
(protons) together inside the nucleus .. we have two
types of a nuclear force:A- Strong nuclear force
Its larger than the other type (i.e weaker nuclear force)
it acts as the glue to hold the nucleus against the
repulsive forces that are produced by the protons on
each other .
B- Weaker nuclear forces : its involved with
electron decay from the nucleus . it maybe related to
the electrical forces
FORCES ON THE BODY
They are either those where the body is accelerated (
dynamics ) or where the body is equilibrium (static)
The force that is involved in both statics and dynamics
is called ( friction forces )
1- Statics
When objects are static they are in equilibrium , we
mean by that the sum of forces in any direction are
equal to zero , or the sum of the torques about the axis
= zero
** many of the muscles and bone system of the body
acts as Levers which are classified into :1- first class levers : they are the least common in the
body . the fulcrum point (F) is between the muscle force
(M) and the weigh (W) , for example the HEAD
2-second class levers:they are found more than the
first class levers , here (W) is between (F) and (M) ,
for example STANDING ON TOES
3-third class levers :they are most common in the body
. here (M) is between (F) & (W) , for example the
ARM IN ELBOW JOINT
 in general each muscle has a minimum length to which
it can be contracted and a maximum length to which it
can be stretched and still function .
 at these 2 extremities ( i.e minimum and maximum
lengths ) the force that that the muscle can exert is
essentially = zero
** we can fin the force supplied by any muscle by this
equation
4M=7.5W
Where ;
M: muscle force
W: weight
This equation is used when we neglect the weight of
the forearm and hand , for example , as in finding the
force supplied by biceps muscle.
But when we don’t neglect the weight of the hand and
forearm the equation will be
M=3.5H+7.5W
Where;
H=weight of forearm and hand
Another thing that we must study is the
TENSION
T=2W1 + 4W2/ Sin α ( for arm and deltoid muscle)
The equation above is derived from
28T Sin α = 36W1+72W2
See This following diagram is between ( maximum
force / area ) and (the length of them uscle ) this diagram
is very importan
Notes :
1- at the rest of the muscle ( at resting length ) a muscle
is close to its optimum length for producing force
* resting length in the diagram = L
2-at about half this length (i.e L/2) it cant shorter further
and the force that the muscle can produce , drops
3- at strech ( about 2L) a reversible tearing of muscle
take place
 here are examples of dynamic forces
1-a 60 kg person walking at 1 m/sec , pumps into a
wall and stop in a distance of about 2.5 cm in about
0.05 sec .
What is the force developed on impact ???
Solution :F= m * ∆ v /delta t
Mv = moment = mass * velocity
M* ∆v = the change of the momental
m*v1 – m* v2
…….
M ∆ v = 60 * 1 – 60* 0 = 60 kg.m/sec
F= 60/0.05 = 1200 Neuton =1200 kg.m/sec²
2-DYNAMICS
This force is important when the body is moving and
hitting another body .
It appears on the body when acceleration or
deacceleration is involved . this force is used in the
forensic medicine
**nueton originally wrote the law to measure this force
he said that
Force = the change of movement or delta (mass*
velocity )/short time interval (delta t )
F= ∆ (mv)/ ∆ t >>>>> F = m/∆ v/∆ t
>>>> ∆ v / ∆ t = a >>>> F = ma
F=force
Where ;
M: mass
V: velocity
A: acceleration
NOTE :
The increase of weight when the heart beats (systolic) is
an example of a dynamic force in the body
THE EEFECT OF ACCELARATOIN
1- an apparent increase or decrease in body weight
2- changes in the mineral hydrostatics pressure
3-distortion of the elastic tissue of the body
4-the tendency of solids with different densities
suspended in a liquid , to separate
5- if the acceleration becomes large , the body will lose
control because it doesn’t have adequate muscle force to
work against the larger acceleration forces
6- under certain conditions the blood may pool in various
regions of the body . the location of pooling depends
upon the direction of acceleration.
If the person is accelerated in the head , the lack of blood
flow to the brain can cause blackout and unconsciousness
7- astronauts in an orbiting satellite are in a condition of
a weightlessness some physiological changes take place
8-tissue can be distorted by acceleration and if the forces
are very large tearing can take place
 here are examples of dynamic forces
1-a 60 kg person walking at 1 m/sec , pumps into a
wall and stop in a distance of about 2.5 cm in about
0.05 sec .
What is the force developed on impact ???
Solution :F= m * ∆ v /∆ t
Mv = moment = mass * velocity
M* ∆v = the change of the momental
m*v1 – m* v2
…….
M ∆ v = 60 * 1 – 60* 0 = 60 kg.m/sec
F= 60/0.05 = 1200 Neuton =1200 kg.m/sec²
Note: N =Neuton, which is the unit of force
Example -2-
A person walking at 1m/sec.hits head on asteel beam
.Assumehis head stops in 0.5cm in about 0.01sec.If the
mass ofhis head is 4kg,what is the force developed ?
*Solution:
F=m∆/∆t
m∆v=4*1-4*0
=4kg m/sec.
F=4/O.O1 = 400 N
Example-3 –
Concerning the (example -2-).If the steel beam has 2cm
of paddinga ∆t is increased to 0.04 sec .What is the force
developed ?
*SolutionF=m∆v/∆t
Example -4-
=F=4/0.04 =100N
If a person jumps from a height of 1m & Lands stifflegged .The body is travelling at 5m/sec,just prior to
hitting, if he stops at about 0.005 sec. The force in leg is
about 100 times the persons weight, prove that ?
Solution;W=m*9.8 (W=weight )
M=W/9.8
F=m∆v/∆t = W/9.8 *5 /0.005
F =W/0.01 =100W
Pains
Frequency
Jaw Pain
Head Pain
Impaired Speech
Chest Pain
Painful Breathing
Abdominal Pain
Lumbosacral Pain
Urge to defecate
Urge to urinate
6-8 Hz
13-2 Hz
13-20 Hz
5-7 Hz
1-3 Hz
4.5 – 10 Hz
8 -12 Hz
10.5 – 16 Hz
10 – 18 Hz
Physics Of The Skeleton
Most of the skeleton is made of bones hold together
by ligaments.
Functions Of Bones Or Skeleton
1. Supporting for example muscles & bones of leg .
2. Locomotion for example bone joints permit movement
of the bones.
3. Protection for example, skull protects the brain & the
ribs protect the heart & lung….etc
4. Storage bones store chemicals for example the “Ca” is
stored in the bones which is released when it is needed.
5. Nourishment for example teeth & jaws.
6. Sound transmition for example the ossicle in the
middle ear
7. Production of RBC in bone marrow
*Note: the muscles are attached to the bone by mean of
tendons and ligaments , the system of bones + muscle
support the body
**Note : the teeth are specialized bones that can cut food
incisors tear it , canine cut it and molars grind it , thus the
teeth serve in providing nourishment for the body
*** Note: the smallest bone of the body are the ossicles
in the middle ear , there are three small bones act as
levers and provide an impedance matching system for
converting sound vibration in air to sound vibrations in
the fluid in the cochlea ( they are the only bones that
attain full adult size before birth )
FORCES ON THE BONE :
The functions would determine the shape of the bones ,
the internal constriction of the bone and type of material
to be used
If we sort all of the approximately 200 bones of the body
into various piles according to their shapes we might
come up with 5 piles these piles are :
1- FLAT BONES : there are plate like bones such as the
shoulder blade ( scapula) and some of the bones of the
skull
2-LONG HALLOW BONE : such as those of the arms ,
legs and fingers
3-CYLINDRICAL BONES : such as vertebrae
4-IRREGULAR BONES : such as the bones in the wrist
and ankle
5- THE RIBS : they don’t belong in any of the other four
piles
*Note : bones are made of
1-hard tissue
2-tough cover
3- blood vessels
4-marrow
**note : the bones are very strong that can support the
body weight and other forces such as bending , running ,
jumping (strain and stress) , then we can find the relation
between the strain (∆L/L) increases linearly at first
indicating that is proportional to the stress (F/A) as
shown in figure
F/A = Hook’s law = the stress
F : the force in neuton (N)
A: Area (in mm²)
So F/A (the stress) is in the N/mm² unit
As the force increases the length increases more rapidly ,
the bone breaks , at a stress of about 120 N/mm².
The ratio of stress to strain in the initial linear portion is
called “Young’s modulus”
Young modulus = (F/A)/ (∆L/L)
Or
Y=LF/A∆L
Also we can calculate ∆L (from the above equation)
∆L= LF/LY
*Note” 120 N/mm² =12000N/cm²
** Hook’s law written the limits of the perfect elasticity
strain is directly proportional to stress
Self test 1 :
Fill in the blanks with suitable words :
1- magnetic forces divided into a:……………. ,
b:……………….
2- many muscles and bone system act as ……….
3-the equation which refer for the force supplied by
the biceps muscle is …………
4- types of bones are : 1:…………… , 2:………. ,
3:………. , 4:………..
5: function of bones or skeleton
1 :…………….. , 2:…………… , 3:…………. ,
4:……………
Self test 2 :
Talk about types of bones , and what are they
made of
Check your answeres in the key answer page at the end
of the lecture
Key answers
PRE TEST
Question number
1
right answer
a
2
3
4
5
a
a
c
d
Self test
1- a:weak nuclear ,b: strong nuclear force
2-levers
3- M=3.5H+7.5W
4_ 1-flat bones , 2-long hallow bones , 3cylindrical bones , 4-irregular bones
5-1. Supporting for example muscles & bones of leg .
2. Locomotion for example bone joints permit movement
of the bones.
3. Protection for example, skull protects the brain & the
ribs protect the heart & lung….etc
4. Storage bones store chemicals for example the “Ca” is
stored in the bones which is released when it is needed.
Self test 2
1- FLAT BONES : there are plate like bones such as the
shoulder blade ( scapula) and some of the bones of the
skull
2-LONG HALLOW BONE : such as those of the arms ,
legs and fingers
3-CYLINDRICAL BONES : such as vertebrae
4-IRREGULAR BONES : such as the bones in the wrist
and ankle
5- THE RIBS : they don’t belong in any of the other four
piles
*Note : bones are made of
1-hard tissue
2-tough cover
3- blood vessels
4-marrow
REFERENCES:
Basic physics and measurements in anesthesia …..
william meinemann medical books …..
E.O.parbrook
Ministry of Higher Education and
Scientific Research
Foundation Of Technical Education
Technical Medical Institute
Training package ( 7 + 8 )
In
Application of electricity and magnetism
in medicine
For Students /
First Class of Anesthesia
Department
By :
Dr. IKBAL ABDULHAMED
1 / OVER VIEW
DEC / 2009
1 /A- Target Population :
This Directed To Class One Students In
Anesthesia Department Of Technical Medical
Institute.
1 / B – Rationale :
This lecture give the important definition & the
application of physics in medical & the
measurement in operating room & (caution ) in
side this room & the instruments in .
1 / C – central idea
The central idea includes :
1: He must know the above electrical contact is
made on the surface of the body and the level of
current that cause damage and fibrillation is in mA
then its called macro shoc
2- when current is applied inside the body then it
doesn’t have to pas the high resistance of the skin
then a ventricular fibrillation can be induced by
much smaller than the current levels of macro
shocks
through the major vessels and touching the heart
muscle to stimulate the heart if on timing
mechanism should fail . AC and one as ground
wire which is connected to the other 2 wires
throught 2 capaceters the value of which depent on
the potential difference and frequency of AC power
supply to pass the unwanted leakage current that
may cause fibrillation ( 30µA)
3- Know that the low frequency electricity and
magnetisms in medicine.
5- To know about the cardio vacular
instrumentation & Instrument used in cardio
vascular are of 2 groups :
1-instrument used for monitoring(diagnosis):
A-ECG and electrodes
B-amplifiers
C-heart rate meter
D-oscilloscope
2-theuraputic devices :
A-defibrillator: is a device which initiate the
normal heart rhythm
B-pacemaker :which can keep the normal rhythm is
going
how be work (application ).
1 / D – Instructions
1- study the over view very well.
2- Identify the new words in electricity &
megnetisim & how? he must see in operating room
& all the instruminations that includes.
3- Do the pre test if we get
a-Five degree & more so we don’t need to study
the subject then consult the instructor.
b-less then 5 degree so we need to study the subject
and continue in our studying …
4- after our studying to these subject content do the
post test , if you got :a- five and more then pass to study the second
lecture
b-less than five degree then go back to study the
first lecture or any part of it then do the post test
again
2/ performance Objectives
After studying the (7 + 8)lectures the student will
be able to
1- Must know the above electrical contact is made
on the surface of the body and the level of current
that cause damage and fibrillation is in mA then its
called macro shock
2- To know about the cardio vacular
instrumentation & Instrument used in cardio
vascular are of 2 groups.
3/ pre test
Put circle around the letter of the correct ans
wer 1- The level which we can just feel the current
for adult man is
a: 1mA .
b: 0.67mA
c: 0.50mA
d: 0.44Ma
2- Maximum current that will not induce fillbirll is:
a : 100√t mA
b: 116√t mA
c: 50*1 / t mA
d :116/ √t mA
3- Faradays law is the relationshipe between a
voltage V magnetic field B & the velocity v is
a- V = B /v
b- B = Vv
c- V = Bv
d- v = V / B
4- Micro shok is called when
a- 30µA
b- more than 30µA
c- less than 30µA
d- 50µA
5- Is an instrument that connecting to the body by
electrodes to record the electrical potentional of
heart
a-E.C.G.
b-pasemakers
c- defibrillators Check your answer in key
answer page at the end of the lecture
NOTE: 1 degree for each answer
The subject content
Electrical Shock
1- The level at which we can just feel the current
(the perception level ) for
A- Adult man js 1 mA.
B- Women is 0.67 mA
At 50 Hz
2-The perception level is frequency dependent, it
rises the frequency increases above 100Hz
3-Between 1 mA for men & 10Ma level it causes
tingling sensitive in the hands.
4-at currents between 10-20 mA muscular
contraction taken place and many subjects cannot
let go of electrodes
5-Near 100mA pain & in some cases fainting occur
. Such current when it passes through the heart then
it is sufficient to cause ventticular fibrillation (rapid
irregular & ineffectual contraction of the ventricles
).
 the heart responds to fibrillation during one
portion of its cyclethe up swing of the T-wave
. it was found that therei s a relation between
the level of the current and the time interval of
exposure to cause induction of fibrillation
 maximum current that will not induce
fibrillation(above which fibrillation will
happen (Imax)
Imax=116/√t mA
T: time in seconds
Then for exposure time A:t = 1 sec*Imax=166√t
mA
B:t=4 sec
*current levels of 6 A and above cause sustained .
 to treat a patient with a trial fibrillation in this
case the defibrillator electrical pulse is applied
after the R-wave ( depolarization of the
ventricles) , but before the up swing of the Twave
notes:
 it has been estimatd that 30µA through human
heart would cause ventricular fibrillation this
exposure is called micro shock
.some other cathters contain wires or electrically
conducting fluids which provide directly paths to
the heart
 to protect patients from micro shock the
instrument power supply have 3 wires to form
2
1- measurement of blood flow by electromagnetic
method : when electrical conducter is moved
perpendicular to a magnetic field , a voltage (V) is
induced in the conducter propotional to the product
of magnetic field (B) and the velocity (v) of the
conducter (Faraday’s law)
Vα Bv
This law is also holds for conducting fluids moving
perpendicular to magnatic field such as blood
Then Bvd where
D: is the diameter of the conducter blood vessels .
V,d and B can be measured then
The mean velocity (v) = V/Bd
The volume flow of blood (Q) = mean velocity *
area of the blood vessele (л d²/4)
Q= (л d²)/(4 *V/Bd)
A-ECG: is an instrument that is connecting to the
body by electrodes to record the electrical potential
of heart ar different locations .
Electrodes :the body can be treated as a path of salt
water in which the current flow in the form of the
ions while in wires and electrodes the current flow
in the form of moving electrons .
The the interface between the body suface and
metal electrodes ions flow must be converted to
electron flow through chemical reaction
1- if ordinary metal are used as electrodes then
polarization vessels from this chemical reaction at
one or both electrons gas bubbled form due to
water electrolysis and then the interface will be
electrically unstable this produce electrical noise
which will be much larger than the ECG signals
2-to avoid such problem then silver-silver chloride
electrodes in which
A:current passes so easily
B: there is no gas formation
C: there is no electrical noise
 the connection of electrodes to the skin
interface must be done by putting the electrode
with small distance between and the space
filled with a conductive paste because complex
layers of +ve and –ve charges form this double
layers should not be disturbed by patient
movement
** ECG must be taken in resting because there is
metabolically potential generated of about 40 mv
between the inside and outside of the skin , if this
was stable it will cause no problem but it causes
large artifacts in ECG during exercising or rolling
over in bed
B-amplifier :in a typical building the current from
the power supply coactively coupled into the body
from 220 v and 50 Hz power line which can
produce.
Much larger potential than the typical ECG signal
(1mv) this undesirable interference voltage is ten
times larger and is added to the ECG potential
making the ECG nearly unobservable and useless .
 to avoid this interference voltage we use
differential amplifier which measure the
interference voltage and eliminate (subtract) it
from the final electrical signal to allow only
the ECG signal appears on the tape or on the
oscilloscope screen
hear rate meter :electronic device measures the
time between successive R waves of the heart cycle
P-ORS-T the inverse of this R-R interval is the
heart rate and this rate is indicated on meter
example : if R-R interval = 0.01 min/cycle
the heart rate =1/0.01 = 100 pulse/minute
the patient monitoring
when a routine diagnostic ECG is taken , a
permanent record is required but such permanent
record is impractical for continuous monitoring of a
heart attack patient then monitoring display on
oscilloscope
2-if the heart stops or if its rate drops below
50beats/min the meter needle contacts the low
alarm then sounding alarm
3-some times there are a number of false alarms
which may due to
A-artifacts arising from trans conditions such as the
patient turning over
B-the paste between the electrodes and the skin
body may dry out
C- the electrode may fall off
For the above 2 reasons B and C then a special
circuit is employed to identify zero reading or
straight line to the oscilloscope – A small high_
frequency current is passed from one wire through
one electrode through the body to other electrode if
either electrode fall off , this continuous circuit is
broken
Theurapeutic devices
1-defibrillators:- many heart attacks patients
undergo sudden changes in rhythm , ten therapeutic
action can be taken to save their lives , by correct
the uncoordinated twitching of ventricular
fibrillation
Ventricular fibrillation is a rapid ,irregular and
ineffectual contraction of heart ventricles ,
defibrillation is done by using defibrillator
*put the paddles (metal electrodes 7.5 cm in
diameter of silver silver-chloride) that are coated
with conductive paste above and below the heart
* when the switch is put on a current ~ 20A flows
through the heart at the same time – all muscle
fiber then recover(Relax) at about the same time (5
milliseconds) and the heart can initiate normal
rhythm again .
2-pacemakers : the atria of the heart are separated
from the ventricles by a fatty layer that doesn’t
conduct electricity to propagate directly from atria
downward . at a single location , the
atrioventricular node (AV node) impulses are
conducted to the ventricles which perform their
contraction. If AV node damaged or covered by
fatty layers , the ventricles receive no signals , but
the ventricles do not stop pumping because there
are natural pacing centers in the ventricles that
provide a pulse if none has been received from the
atria for 2 sec. the resulting pulse rate 30-50
beats/min will sustain life but not in complete
efficiency. To improve the quality of life of such
patients an artificial pacemakers have been
developed which contains a pulse generator which
can be regulated to fire the same pulse rate of SA
node of the same patient.
Self test :
Fill in the blanks in suitable words
1-the level at which we can just feel the current for
women is ……….. at 50Hz.
2-near 100 mA pain and some causes ……..
occurs.
3-measurment of blood flow by ……. Method
4-the volume flow of blood is ……… .
Check your answers in the key answers page at the
end of the lecture
Key answers
Pre test
Question number
1
2
3
4
5
Self test
1- 0.67 mA .
2-fainting
3-electromagnetic
4-Q=πd²/(4*v)B*d.
right answer
a
b
c
a
a
References
Basic physics and measurement in anesthesia
William meinemann medical books .E.O parbrook
Lectures of Baghdad and mustansrya university
/medical college
Ministry of Higher Education and
Scientific Research
Foundation Of Technical Education
Technical Medical Institute
Training package ( 9 + 10 )
In
Diffusion of Gases
For Students /
First Class of Anesthesia
Department
By :
Dr. IKBAL ABDULHAMED
Dec/2009
1 / OVER VIEW
1 /A- Target Population :
This Directed To Class One Students In
Anesthesia Department Of Technical Medical
Institute.
1 / B – Rationale:
This lecture give the students the impotant
definitions of diffusion & the main factors that
the diffusion depend on , the laws that they
related to the diffusion of gases general &
specially the two important gases O2 & CO2
which they related with partial pressure ,
solubility of them & CO – Poisoning..
1 /C – Central idea
The central idea includes :
1. know what we mean by diffusion of gases
laws of gases .
2. why the gas diffused ?on what important
factors depend.
3The molecules move under many process.
4. The laws of gases ( Fick law , Grahams law
,Henrys law ).
5. The effect of the partial pressure temperature
on diffusion.
6. Oxgen transport ( dissolving , combination
with hemoglobin ( Hb ) & CO – Poisning. &
treatment.
1 / D – Instructions
1. Study the over view very well.
2. Identify the aims of studing thediffusion of
the gases .
3. The laws of diffusion
4. we do the pre test if we get a- five degree and
more so you don’t need to study the subject then
consult the instructor
b-less then 5 degree so you need to study the
subject and continue in your studying …
4- after your studying to these subject content
do the post test , if you got :a- five and more then pass to study the second
lecture
b-less than five degree then go back to study the
lecture or any part of it then do the post test
again.
2 / Performance Objectives
After studying the lecture the student will be
able to
1- know what meaning of diffusion of gases &
focusing on the important gases O2 & CO2 &
CO .
2- the factors that the diffusion of gases depend
on.
3-The laws that related to this diffusion (Ficks,
Grahams,Henrys laws ) .
3 / Pre test
Put circle around the letter of the correct answer
1.Diffusion of gases depend on
a-Gas molecules move from higher partial
pressure to low parial pressureof the gas.
b. moving against in step (a .) .
c. They are stopped in aplace with high
pressure.
2. Ficks law , is the relainships as shown
a. ∆Q/∆x =-KA*∆C/∆t
b. ∆Q/∆t = KA*∆C/∆x c. ∆Q/∆t = -KA*∆c/∆x
(where ∆Q/∆t rateof diffusion )
3- The distance (D) , amolecule will travel from
its origin after (N) collisions is:
a. D = λ√N
b. D λ =√N
c. D / λ =√N
4- Grahams law of diffusion is :
a. Diffusion α 1/√Mwt
b.Diffusion α √Mwt
c. Diffusion α 2√Mwt
d. Diffusion α 1/2√Mwt
5- Dissolved of O2 depend on :
a. only on the body temperature.
b.only on the obey Henerys law.
c. in combination with hemoglobin.
d. obey Henerys law & on the body
temperature.
The subject content
DIFFUSION OF GASES
1 . Gas molecules move by process known as
diffusion from a place where ther is a higher
partial pressure of the gas to one where there is
alower partial pressure.
2 .This is a molecular process.
3 . By diffusion ,gas moleculethe can move
through the pores of a porous membrane to
equalize the partial pressures on their side.
Ex: O2 passes from the alveoli in to the
pulmonary capillary blood by a passive process
of diffusion.
4 .The diffusion is based upon Fick s law.
Ficks law :
States that ,the rate of diffusion is
proportional to the concentration gradient in
the direction of diffusion.
∆Q/∆t = - KA( ∆C/∆x ) , ∆Q/∆t : volume of
O2 diffusing across the alveolar membrane at a
time interval ∆t .
K = Diffusion constant
A = Area
∆C /∆x = Concentration gradient
5 . The diffusion result from a random motion of
the molecules.
The distance ( D ) ,a molecule will travel from its
origin after ( N ) collisions is
D = λ√ N , N = No. of collisions , = mean free
paths.
In air , λ = ~ 10‾7 m
I n tissue , λ = ~ 10‾¹¹m
Example :
What is the typical value of D in air
and for an O2 molecule after 1 sec. if N = 10‾10
in air and N = 10¹² in tissue ?
In air D = 10‾7 * √10¹º = 10‾² m
In tissue D = 10‾¹¹* √ 10¹² = 10 ‾³‾² m
6 . Diffusion depend on :
b. Temp.
c. Diffusion in partial pressure (not total
pressure ) . d. Mass of molecule ( molecular
weight ) . e . Solubility of the gas.
7 . In the diffusion of O2 & CO2 across the
alveoiar membrane CO2 –diffuses rapidly.
The diffusion of CO2 in ~ 20 times greater than
the diffusion of O2 . Because CO2 is much more
water soluble than O2 & this help to increase
the rate of diffusion .
Diffusion Capacity
∆Q/∆t = - D ( P1 - P2 ) ,D = Diffusion Capacity
( P1 – P2 ) = change in
partial pressure (mmHg )
In the lung , the diffusion capacity is defined as ;
D = ∆Q/∆t / (PO2 ) 1 – (PO2 )2
= O2 – up take (ml /min ) / alveorar PO2 –
capaillary PO2
Atypical value of the O2 –diffusion capacity=21ml
O2 /min / mmHg.
Graham 's Law of Diffusion
State that the diffusion of gases through a
certain membranes is inverseiy proportional to
the square root of their molecular weight.
Diffusion α 1 /√ molecular weight
*according to this law ,
Mwt of O2 = 32 , Mwt of CO2 =44
O2 willdiffuse faster than CO2 (by 20 %
)through a dry porous membrane .
But in practice
 The nature of the membrane is very
important important.
 For example ; CO2 diffuse more rapidly
than O2 through a rubber –lined Douglas
bag.
 Silcon rubber is good for artificial lung.
The Solubility of gases in liquid
1. In general , gases are soluble in liquids .
2. Henr's Law : The amount of a given gas which
dissolve in a given liquid is directly proportional
to the pressure ( partial pressure ) of the gas.
3. The amount of gas which goes in to solution
depends upon the Temp. of the liquid .
The higher the temp. of the liquid, the less amount
which goes in to solution .
Oxygen Transport
O2 is carried in blood in two forms,
1. Dissolved
2. combination with
hemoglobin.
1 . Dissolved – O2
a. This obeys Henry law ,that is ,the amount
of O2 dissolved is proportional to the partial
pressure.
B . Atbody Temp. 1 liter of blood plasma at a
PO2 of 100mmHg will hold only ~ 2.5cm³ of O2
at normal temp. & pressure (NTP ).
2. Combination with hemogloblin ( Hb )
a. Most of O2 for the cells is carried in
chemical combination with hemoglobin (Hb ) in
RBC.
b. 1 liter of blood can carry ~ 200cm³ of O2 at
NTP.
MOST OF O2 IS NOT DISSOLVED.
c. O2 forms an easily reversible combination
with hemoglobin (Hb) to give Oxyhemoglobine
O2 + Hb →→←← HbO2
d. The O2 –will combine with or separate
from (Hb) in way that depend on the
dissociation curve.
During heavy excerise (working muscles )
a.PO2 →→ in the muscles drops rapidly.
b.PCO2 →→ increased
c. pH ( acidity ) →→ increased
d. Temp. of working muscles →→
increased
Then working muscles can obtain 10 times more
O2 than they consume at rest.
CO----Poisoing
1 .The CO- molecules attach very securely to the
Hb at places normaly used by the O2 .
2. They attached ~ 250 times more tightly than
O2.
3. The CO- inhibits the release O2 from Hb.
4. CO- can cause death by starving the tissues of
O2.
5. Treatment
If a CO – VICTIM is plased in a
hyperbaric O2 – Chamber with absolute
pressure (3 atm. ) of pure O2 the PO2 increases
by afctor of 15.
This therapy can not be maintaind very long
because O2 –Poisoning can result.
.
Self test 1:
What are the important factors that the diffusion of
gases depend on ?
Self test 2:
Write brefily about Oxygen transport in the
blood.
Self test 3 :
State the important points during heavy
excerise ( working muscles ) due to the behavior
of O2 & CO2 ?
Self test4 :
Write the important points that occure in COPoisioning and the treatment ??
Key answers
PRE TEST
Question number
1
2
3
4
5
right answer
a
b
a
a
d
Self test one
The factors are
a. speed of molecules
b.Temp.
c. Diffusion in partial pressure (not total
pressure ) . d. Mass of molecule ( molecular
weight). e . solubility of the gas.
Self test two
O2 is carried in blood in two forms,
1. Dissolved
2. combination with
hemoglobin.
1 . Dissolved – O2
a. This obeys Henry law ,that is ,the amount
of O2 dissolved is proportional to the partial
pressure.
B . Atbody Temp. 1 liter of blood plasma at a
PO2 of 100mmHg will hold only ~ 2.5cm³ of O2
at normal temp. & pressure (NTP ).
2. Combination with hemogloblin ( Hb )
a. Most of O2 for the cells is carried in
chemical combination with hemoglobin (Hb ) in
RBC.
b. 1 liter of blood can carry ~ 200cm³ of O2 at
NTP.
MOST OF O2 IS NOT DISSOLVED.
c. O2 forms an easily reversible combination
with hemoglobin (Hb) to give Oxyhemoglobine
O2 + Hb →→←← HbO
Self test three
During heavy excerise (working muscles )
a.PO2 →→ in the muscles drops rapidly.
b.PCO2 →→ increased
c. pH ( acidity ) →→ increased
d. Temp. of working muscles →→
increased
Then working muscles can obtain 10 times more
O2 than they consume at rest.
Self test three
1 .The CO- molecules attach very securely to the
Hb at places normaly used by the O2 .
2. They attached ~ 250 times more tightly than
O2.
3. The CO- inhibits the release O2 from Hb.
4. CO- can cause death by starving the tissues of
O2.
5. Treatment
If a CO – VICTIM is plased in a
hyperbaric O2 – Chamber with absolute
pressure (3 atm. ) of pure O2 the PO2 increases
by afctor of 15.
This therapy can not be maintaind very long
because O2 –Poisoning can result.
REFERENCES:
*Basic physics and measurement in anesthesia…..
William meineman medical book…..E.O.Parbrook
* LECTURES OF MIDICINE COLOGE OF
BAG. UNV.& MIDICINE COLOGE OF
MUSTA.UNV.
Ministry of Higher Education and
Scientific Research
Foundation Of Technical Education
Technical Medical Institute
Training package ( 11+ 12 )
In
Electrica safety and heat and cold in medicine
For Students /
First Class of Anesthesia
Department
By :
Dr. IKBAL ABDULHAMED
Dec/2009
1 / OVER VIEW
1 /A- Target Population :
This Directed To Class One Students In
Anesthesia Department Of Technical Medical
Institute.
1 / B – Rationale:
This lecture give the students the knowledgment
about the electrical safty & heat and cold in
medicine, the prevention os staic charges
formation ,electrical shock,heat cold
temp.measurment & other devices &
pneumograph .(in operating room).
1 /C – Central idea
The central idea includes :
1. know what we mean by the source of ignition
in operating room.
2. why these occurs in these places ? what are
the methods to prevent these ignitions.
3. To know what are these ignition like
(spark,from electrical apparatus from insultaing
surfaces ,from voltage generators…
4.To know about some zones of danger
&ventilation…….
5. The effect of the temperature & what we
mean by heat & cold in medicine & what we
mean about thermister (
pneumograph),thermo couple .
1 / D – Instructions
1. Study the over view very well.
2. Identify the aims of studying electrical
safty& the source of ignition , how to
prevent these thing in the operatin room.
3. methods to prevent the static charges
formation.
4. To know how the heat & cold in
medicine (heat & the temp.measurment
devices ,glass fever thermometer,thermister
(pneumograph) ,thermocouple.
5. we do the pre test if we get a- five degree
and more so you don’t need to study the subject
then consult the instructor
b-less then 5 degree so you need to study the
subject and continue in our teaching&
studying….
2 / Performance Objectives
After studying the lecture 1- know how the
electrical saftey in operating room how to be.
the student will be able know how the main
factors which causes these ignition & the
prevention of static charges formation ,electrical
shock (types ) ,heat & cold in medicine
temperature measurement devices .
3 / Pre te
1. Assay the methods that we can prevent of
static formation in operating room ?
2. write briefly about what we mean by
electrical safety & the prevention of static
charges formation in operating room?
3. The source of ignition in operating room.
4. Elecrical shock ,zones of danger &
ventilation.
5.Show how heat & cold in the medicine &
Devices.
The subject content
ELECTRICAL
SAFTEY
n operating room the source of ignition are:
1. Sparks arising from the build-up of
electrostatics chargers or produced at electrical
contracts.
* sparking or arcing generated by surgical
diathermy unit.
2. Only a minute amount of energy (= 1 micro
joule) is needed to ignite on explosive anesthetic
mixture.
3. Static electric chargers are generated when the
insulating surfaces are rubbed together and then
rapidly separated .
4. Static chargers are produces in voltage
generators
Prevention Of Static Charges Formation
1.Antistatic flooring :
The floor of operating room is made from
special material called (( antistatic terrazzo steel ))
*these materials increases the resistance between
the patient and staff ) and the earth.
* The average resistance for antistatic floors
surface should be not more than 2MΩ.and with the
surface (wet) the average resistances to earth
should not be . less than 59kΩ
2.
Antistatic rubber :
The wheels of trolleys and the feet and
stocks and the soles should be made from
antistatic rubber.
* also anesthetic equipment such as re breathing
bags and anesthetic tubing should be mad from
antistatic rubber
*antistatic rubber is defined as ; a rubber
possessing a resistance of great ther the 50 kΩ
and less than 100MΩ. (= 1MΩ)
3. Clothing
:
* Shirts and jumpers made from synthetic
fiber materials such as nylon are capable of
produce a significant degree of chargers.
:. Suits should be made of antistatic materials
such as cotton , and boots or overshoes must be
antistatic
4. Antistatic
sprays:
*most of apparatus found in operating room is
made of metal which is a good conductor of
electricity or its made of antistatic rubber .
However an insulating plastic such as Perspex
occurs in the covers of the anesthetic machine and
the Perspex containers of soda lime used in circle
breathing systems
** in order to prevent the build up of charge on
these sites , its desirable to spray the Perspex with
an antistatic spry .
5. Humidification
* The typical relative humidity in the operating
room is = 75% .
* It can be tolerated by using full air
conditioning.
**Sparks
from Electrical apparatus :
1. When an electrical circuit is opened or closed a
spark often occurs at the switch contacts ( such as
that of an electric motor)
2. These effects are more pronounced in d.c than
in A.c circuit because the voltage falls to zero
every – cycle
3. Ssparking also occurs at thermostat contacts
and some type electric motors .
* these types must not be used in surgical suction
apparatus
(note> explosions have been cavsed by an
accumulation of ether and oxygen in the sucker
housing )
*its frequently used a special type motors having
no sparking source , ( example compactor type
motors )
4. Some apparatus , such as D,c defibrillation
should be fully sealed to prevents the ingress of
anesthetic mixtures .
**some zones of danger and ventilation:
*The most dangerous region in the operating room
its of will be immediately adjacent to the .
anesthetic machine , tubing relief valve , reservoir
bag and the patient , particularly his head.
*because only ethylene is lighter than air , any
ether vapor or cyclopropane present in the
atmosphere will gravitate toward the floor.
* Ventricular fibrillation : Is defined as
Rapid irregular and ineffectual contraction of the
heart muscle
*safe current :
Its as a max current that will not induce fibrillation
in man
Its I max= 116/√t (mA)
t= time (sec)
4. when I ≥ 6 A ☞ its accurse temporary
respiratory paralysis and series burns .
*A, Damage of macroshock depends on ;
1. The individual.
2. The dampness of the skin.
3. contact of the skin with conductor.
B, micro shock :
1. It is occurs in ICU ( intensive car units)1,
2. Occurs when the current (I) follows the arteries
and passé directly through the heart
3. When I = 30 micro ampere →ventricular
fibrillation
4. The main source of micro shock is →due to the
broken ground wire.
* The air extraction points should be placed near
floor level , inlet points as high as possible ( ≈ 2
m)
*The ventilation system should be provide an
ambient tepe of 18 c◦ with air movement of 0.15
m/sec
((Electrical shock))
Thes are twq types ;
A. Macro shock
B. Micro shock
A. macro shock
Its occur when electrical contact is made on the
source of the body
At Ac ˜ current , with (60Hz)-(50Hz)
Current with frequency – (60 Hz) is called lethal
frequency
1, if I = 1 mA → its occurs perception or (just feel )
2, if I = (10-20-) →Tingling sensation the hand.
3, if I = 50 ma → pain and fainting occurs in thorax
4, when I = 100 mA → current passing through
the heart →caucus ( ventricular fibrillation )
*Solid →(heat)
medicine
liquid →(heat)gas →ions
Heat and cold in the
1. Physical basis of heat and temperature
matter is composed of molecules that are in
motion;
a. in gases or liquid . the molecules move
about . hitting one another or hitting the walls
of the container .
b. in solids , the molecules have same
motion about the sites that they occupy within
the crystal structure .
Note : when the molecules move that means :
They be have kinetic energy and this kinetic
energy is related to the temperature.
K.N ą temp
We know that : At which the K.E of the matter
is called absolute temp or absolute zero or
zero Kelvin = ok° and (273 + C°= K°).
*Heat : It is the energy transferred from the
hot object to cold object ,causing the temp to
ries in the cold object.
*The mercury is used in the thermometer in
stead of alcohol because:
1, It has a clear colour , which can be seen
easily .
2, Mercury (Hg) has low a adhesion force with
the wall of the of the glass and has high a
adhesive force .
* Note :
The smaller diameter of the capillary
tube the greater of sensitivity thermometer.
*, tow things increased the visibility of the
capillary of the thermometer
1. the glass case . act as magnifying glass
2. An apaque whit backing
*. When the thermometer is taking from the
mouth it shows the maximum temp . it
reached underneath the tongue . in order to
return the mercury to the bulb , it is
important to snap the thermometer . the temp
may be taken underneath the tongue or in the
rectum.
2, Thermister :
It as a special resistor that changes its
resistance rapidly with temp ≈ 51C°.
*The four resistors are equal and the bridge is
balance.
But when the temp . change it will carouses
thermister resistance to change when the
bridge will be unbalanced and current flow
through the meter (M ).
*, Pneumograph :
It is a thermister which is placed in the nose
of the patient to monitor the breathing rate of
patient by showing the temp . change
between inspire cooling air and expired warm
air .
* the advantages of thermistor :
1.It is very sensitive for measuring temp it
can measure the change of 0.01 c∧ because of
its small mass.
2. It has little effect on the temp of the sour
ending the tissue , that can read temp . very
fast
3. The meter of the thermistor circuit can be
located some distance from the patient.
4. Because thermistor is very sensitive and
very fast for measuring temp , change the it
has been used to monitor the breathing rate of
the patient .
3, Thermo couple:
It is an instrument for measuring temp . it
consists of two junctions of two different
metals .
If the two junctions are at different temp , a
voltage , is produced , that depends on temp
differences . one of the junction is kept mat
different temp . such as in a nice-water bath
*. Note : coper-constant thermocouple is used
to measure temp , (-190C→300C°) and
measure 100C°, the voltage will be 0.004
V=4mv.of individual cell→because it has very
sharp end.
*It used in measuring :
1, temp. ranging between ( -190c∧→300c∧)
2, Temp, of individual cell→ because it has
very short end .
**Temperature measurement Devices
1, Glass fever thermometer :
* It used to know the temp of the body .
This thermometer composed of
A, capillary tube with alcohol or mercury.
B, This capillary tube is surrounded by magnifying
glass in the front
C, An opaque white backing on the back
The principle behind this thermometer is that an
increase in the temp . of different materials
carouse them to expand different amounts.
In this thermometer , a temp . increase carouse
alcohol or mercury to expand more than the glass .
this produces an increase in the level of the liquid.
**Note: if the liquid expanded the same amount
as the glass . the level of the liquid remain
constant with temp.
Self test one: Complete the following
1. Damage of macro shock depend on
………….,…………………..,…………
2. Electrical shock are two types………..
,………..
3. In operating room the source of ignition are
,……………………..,……………………………
…
4. The methods for prevention of static charges
formation in operating
room…………………………
Self test two :Defined the following
1. Heat.
2. Thermistr.
3.Ventricular fibrillation.
4.Glass fever thermometer.
Key answers
PRE TEST
1.Antistatic flooring
2. Antistatic rubber
3. Clothing
4. Antistatic sprays
5. Humidification
Self test one
1a.the individual
b.the dampress of the skin
c.contact of theskin with conductor
2a,macro shock
b.micro shock
.
3-the source of ignition in the operating room are:
a. Sparks arising from the build-up of
electrostatics chargers or produced at electrical
contracts.
* sparking or arcing generated by surgical
diathermy unit.
b. Only a minute amount of energy (= 1 micro
joule) is needed to ignite on explosive anesthetic
mixture.
c. Static electric chargers are generated when the
insulating surfaces are rubbed together and then
rapidly separated .
d. Static chargers are produces in voltage
generators.
4- The methods for prevention of static charges
formation in operating room
a.Antistatic flooring.
b. Antistatic rubber.
c. Clothing.
d. Antistatic sprays.
e. Humidification.
Self test two
1.Heat
t is the energy transferred from the hot object to
cold object ,causing the temp to ries in the cold
object
2. Thermister :
It as a special resistor that changes its
resistance rapidly with temp ≈ 51C°.
*The four resistors are equal and the bridge is
balance.
But when the temp . change it will carouses
thermister resistance to change when the
bridge will be unbalanced and current flow
through the meter (M ).
3. Ventricular fibrillation :
Is defined as
Rapid irregular and ineffectual contraction of the
heart muscle
*safe current :
Its as a max current that will not induce fibrillation
in man
Its I max= 116/√t (mA)
t= time (sec)
4. when I ≥ 6 A ☞ its accurse temporary
respiratory paralysis and series burns .
4. Glass fever thermometer :
* It used to know the temp of the body .
This thermometer composed of
A, capillary tube with alcohol or mercury.
B, This capillary tube is surrounded by magnifying
glass in the front
C, An opaque white backing on the back
The principle behind this thermometer is that an
increase in the temp . of different materials
carouse them to expand different amounts.
In this thermometer , a temp . increase carouse
alcohol or mercury to expand more than the glass .
this produces an increase in the level of the liquid.
REFERENCES:
*Basic physics and measurement in anesthesia…..
William meineman medical book…..E.O.Parbrook
* LECTURES OF MIDICINE COLOGE OF
BAG. UNV.& MIDICINE COLOGE OF
MUSTA.UNV.