Sterilization and disinfection in eye hospitals asim sil
Sterilization and Disinfection –
Common issues often overlooked in
Asim Kumar Sil, DO, DNB (Ophthalmology), M Sc (London)
Vivekananda Mission Ashram Netra Niramay
Chaitanyapur (Haldia), West Bengal
Quantity rests on Quality
• India is one of the best performing countries
in Eye Care in the World.
• “Quality” issue is gradually gaining importance
in eye care and now the current challenge is
matching volume with quality.
• “Safety” is the foundation of quality. In an eye
hospital safety largely depends on Sterilization
• Sterilization describes a process that destroys
or eliminates all forms of living micro
organisms including spores and is carried out
by physical or chemical methods. Autoclaving
(steam under pressure), dry heat, EtO gas, and
liquid chemicals are the principal sterilizing
agents used in hospitals.
• Disinfection is the process of reducing the
number of microorganisms from the surface
where sterilization is not possible.
• A few disinfectants will kill spores with prolonged
exposure times (3–12 hours); these are called
chemical sterilants. At similar concentrations but
with shorter exposure periods (e.g., 20 minutes
for 2% glutaraldehyde), these same disinfectants
will kill all microorganisms except large numbers
of bacterial spores.
• Single most factor that affect the efficacy of both
disinfection and sterilization is prior cleaning of the
• Cleaning is the removal of visible soil (e.g., organic and
inorganic material) from objects and surfaces and
normally is accomplished manually or mechanically
using water with detergents or enzymatic products.
• Thorough cleaning is essential before high-level
disinfection and sterilization because inorganic and
organic materials that remain on the surfaces of
instruments interfere with the effectiveness of these
Theatre lay out and interior
• Three barriers are recommended between
external air and the Operating Room.
• Preferably there should be higher pressure inside
the OR to prevent entry of external air.
• To be careful enough about closing the doors to
prevent contamination of inside air.
• There should not be any window in the theatre.
• Any surface that may gather dust should be
avoided. Ceiling fans are not recommended.
Floor and wall construction
• Nonporous material with minimal joint is
recommended for Walls and floors
• Surface should be smooth for better
• Corners should be rounded
• Thorough wiping of walls and floor with
disinfectants is currently preferred to regular
• Only essential
furniture should be kept
in the OT.
• It should not look like a
• No wooden furniture
should be allowed to
prevent growth of
Sterile unsterile separation
• There should be a system of separation of
sterile and unsterile materials.
• The lay out should have separate sterile and
• Preferred practice is having
an Air Handling Unit (AHU)
with air blown through
HEPA filter. The cost of
installation is of course high.
• At least a split AC should be
• Window AC is not desired.
• Regular cleaning of filters
should be done.
• OT should never be
overcrowded by too many
people to maintain
cleanliness of air.
• Humidity should also be
We trust most on autoclaving for sterilization.
Packing should never be tight.
The indicator tapes should be pasted properly.
Windows of the drums should be open while
autoclaving and immediately shut after the
• Time, pressure should be strictly maintained.
Sterilization Log Book needs to be regularly
• Care is needed about storing of autoclaved items.
Sterilization Protocol (Time Management)
Reaching Time Reaching Time
• Adequate cleaning and allowing adequate
contact period is mandatory for chemical
• Ethyline oxide and Gluteraldehyde are most
• Care should be taken about thoroughly washing
gluteraldehyde from the instruments before use.
• One should not depend much on formalin
sterilization of non autoclavable instruments. ETO
is a better choice here.
Cleaning and inspection of instruments
• Clean immediately after
• Sterilization is never
effective when an
instrument is covered by
blood or lens matter.
• The instruments should be
cleaned using ultrasonic
cleaners and inspected
under illuminated magnifier
before drying and packing.
• Use of compressors is a
good practice to blow the
tubes and canulae.
• The effectiveness of Hand Washing has been proved
• Any person entering the theatre should wash hands with
soap and running water before touching anything.
• A good practice is washing and drying feet as well before
entering the clean area since most of the people use
chappals. Alternately, disposable shoe cover should be
• Change of street cloth, adequately covering hairs and
mouth are mandatory. Nose should not remain exposed.
• One should not enter theater with infectious disease.
• Every care should be taken about movement inside the
theatre to prevent contamination.
• Theatre size should be adequate to allow free movement of
Good & Bad
Head nicely covered
Nose open - bad practice
• Before scrubbing all the
should be removed from
wrist and fingers. Nail
polish is better avoided.
• Liquid soap is always
preferred to soap cakes
• Prescribed contact time
for medicated scrubs
should be allowed.
• RO water is the preferred
choice for scrubbing.
High volume surgeries
• The theatre team should be most vigilant while
performing many surgeries in one session.
• Using the same instrument with inadequate
sterilization in next case is out of question.
• The high speed sterilization in between surgeries
should be carried out efficiently.
• Optimum sterile items should be laid on table
and covered properly. No sterile item should be
left open for a long time.
• In long sessions microscope caps should be
changed time to time.
• Effective Sterilization and disinfection practices
depend on discipline and commitment of staff.
• Leadership of the hospital should create a culture
of quality consciousness and put a process of
measuring the quality outcome.
• Infection Control Committee should meet
• Most important is sharing the data with staff and
include them actively in the process of quality