2. HAZARD
• A hazard is a situation that poses a
level of threat to life, health,
property, or environment.
• Most hazards are dormant or
potential, with only a theoretical
risk of harm
3. • Once a hazard becomes active, it
can create an emergency situation.
• A hazard does not exist when it is
not happening. A hazardous
situation that has come to pass is
called an incident.
4. • Anesthesia and surgery are
conducted in technologically intense
environments that are always
potentially hazardous.
• The most common hazards in
operating room include fires and
explosion, static electricity,
electrical hazards, radiation injury,
air pollution and power failure.
5. FIRES &
EXPLOSIONS
Both of these can cause death or
injury to the patient in the theatre.
• A fire can only occur if we have
three things: spark or a hot surface,
flammable substance and source of
oxygen
6. SOURCES OF
SPARK/HEAT
• Static electricity
• Faulty electrical switches and
apparatus, e.g. saws, plaster cutters
and drills
• Foreign matter, e.g. dirt or grease in
the oxygen or nitrous oxide
cylinders
• Diathermy
8. STATIC ELECTRICITY
• Electricity is present in the
atmosphere.
• A static electric charge occurs if two
materials which conduct electricity
poorly are brought into contact and
then separated
9. • If there is friction or movement
between the two, a spark is
produced and a spark, of course,
can produce an explosion.
• Examples of non-conductors which
can spark if they touch each other
include plastic, woolen fabrics, non-
conducting rubber, and synthetic
materials such as nylon.
10. • These should always be avoided
in the operating theatre, using
special conducting rubber
instead.
• This rubber has graphite
impregnated in it. It is black and
has a yellow coding (either a
yellow line or a stamp) to show
it is antistatic.
11. OTHER PRECAUTIONS WHICH CAN BE
TAKEN TO REDUCE THE INCIDENCE OF
STATIC ELECTRICITY
• The floors in the operating room
should have a conductivity of the
same order as the other items
resting on them. Concrete or
conductive rubber or plastic, placed
on existing floors tend to give the
desired conductivity.
12. • Clothing- If in the operating room,
don't wear clothing that could
acquire a static charge. Avoid wool,
plastic and nylon fabrics and wear
cotton or other anti-static outer
clothes instead.
• Wear aprons of conductive rubber.
Wear anti-static boots or conductive
canvas overshoes.
13. • Maintain a minimum relative
humidity of 60% in the operating
room.
• Static sparks are more frequent
when the air is dry.
14. • Ventilation- Anesthetic gases are
heavier than air and tend to collect
at ground level. Air within one foot
of the ground is the most
dangerous.
• Fresh air should enter at the top and
stale air should be drawn out at the
bottom. For the same reason
switches should not be placed close
to the ground.
15. • Electric switches and electric
apparatus should be inspected
regularly by the electrician.
• Firefighting equipment should
always be available outside the
operating theatre.
• Smoking and open flames must be
forbidden in the operating room.
16. ELECTRICAL HAZARDS
• There are electrical hazards
associated with the operating
theatre and similar situations where
anesthesia is used. They may occur
when patients are:
• Connected to or in contact with
faulty electrically-operated medical
equipment
17. • Accidentally connected to electric
circuits by spillage of blood or saline
into equipment being used
• Dependent on electrical equipment
to replace or support vital organ
functions
18. • Exposed to fire or explosions
• Undergoing treatment when safe
levels of electrical energy are
exceeded.
• Additional care in keeping patients
away from these hazards is needed
when they are unattended or
unconscious.
19. ELECTRIC SHOCK
• Occurs when the body actually becomes
part of an electrical circuit with
significant current flowing in it. Lack of
maintenance and misuse are the usual
causes.
• Individual susceptibility is variable and
extra care is needed if the patient is
strapped to the equipment or is
unconscious.
20. • Wiring defects, faulty equipment
components and deteriorated
insulation all allow abnormally
high currents to flow in
otherwise safe systems.
21. • Lack of maintenance and misuse are
the usual causes. Individual
susceptibility is variable and extra
care is needed if the patient is
strapped to the equipment or is
unconscious.
22. MACRO SHOCK
• Macroshock is the most common
form and occurs when the body
conducts an electric current which
does not pass directly through the
heart. It varies in intensity from
mild sensory stimulation at 5 to 10
milliamperes (mA), becoming more
painful as the current increases.
23. • At 50 to 60mA muscular contraction
occurs and as the current increases
towards 100mA the victim cannot
release his grip and breathing
becomes extremely difficult.
• Somewhere above this level of
current respiratory paralysis, cardiac
arrest and severe burning occur.
24. MICRO SHOCK
• Microshock may occur when very
tiny currents, such as 100μA, are
intentionally or otherwise passed
directly through the heart muscle;
e.g. direct cardiac catheterization,
measurement of cardiac output, etc.
25. HIGH FREQUENCY
CURRENTS
• High Frequency Currents
i.e. alternating currents (AC) above
50 hertz are less likely to produce
electric shock but can cause burns
and interference with other devices
such as pacemakers.
26. DIRECT CURRENT
• Direct Current (DC) is less likely to cause
ventricular fibrillation than high
frequency alternating currents (above
50Hz) but can cause a more pronounced
skeletal muscle contraction. DC passing
through any body tissue for more than
very short periods can cause injury by
electrolysis.
27. • Nerve damage often occurs in
electric shock especially with high
currents.
• The spinal cord may be injured by
large currents passing from head to
foot or from arm to arm.
28. ELECTRICAL
BURNS
• Electrical Burns and Electrically Initiated
Burns.There are three types of electrical
burn injury:
• Carbonization of skin (from burns at
very high temperatures of 1,000°C)
• Flame burns
• Direct heating of tissues by electric
current producing coagulation
29. DIRECT HEATING
• Direct heating of tissues by electric
current producing coagulation and
necrosis at entry and exit points and
associated injury in muscle and
blood vessels etc. through which
current passes.
30. • The associated injury occurs at
some distance from the body
surface and results in much greater
tissue destruction than is apparent
at first inspection.
31. • Patients suffering impaired
circulation and prolonged contact
may be burnt under conditions
which would not hurt a healthy
person, while those insensitive to
pain or under anesthesia may not
realize that they are being burnt.
32. ELECTRO SURGICAL
UNITS
• Electrosurgical Units e.g. diathermy are
arranged so that current from the active
electrode flows through the patient and
back to the generator via the dispersive
cable.
• For example, with a broken dispersive
cable, the current may return via ECG
electrodes.
33. • Electric blankets have large surface
areas but also many pressure points
through which high current levels
may pass, generating heat.
• Don't use electric blankets in
conjunction with electro-surgery.
Use a water blanket instead.
34. • Poor sitting of return electrode. It
should be near the operation site
and where sufficient soft tissue
provides a large contact area.
• Damaged leads, electrodes, etc.
35. • Skin preparation materials may
impair the function of the skin as a
return electrode region. If these
preparations are flammable they
may ignite.
• Electrically initiated burns may
occur when patient heating pads,
lamps, humidifiers etc. are used to
excess.
36. • Unintentional overheating or
overcooling of blood before or
during transfusion may damage the
blood or even result in cardiac
arrest.
37. POWER FAILURE
• Critical areas employing electrically
driven equipment such as some
respirators (Ventilators) and dialysis
machines require standby
equipment (i.e. generators) to deal
with this emergency.
