About operation theater sterilisation

1. Operation Theater
Sterilisation
Dr.G.UMA
Associate Professor
Dept of Anesthesiology
Karpagavinayaga Institute of
Medical Sciences & Research Center
Madurantakam

2. History of Sterilisation
• Book of Leviticus in BIBLE
• Chapter 11-15
• Code of Hygiene

3. GREEK ERA
ARISTOTLE
• Advised Alexander the great & his Army the use of boiling
water as disinfectant.
• He Recommended Hygiene for Healthy living.

4. Concept of Disinfection
• Practice of Hand washing
Semmelweiss emphasized the importance of washing hands
in chlorinated water in obstetrics to reduce maternal
Mortality.
Florence Nightingale Insisted that the very first requirement in
Hospitals is that DO NO HARM.

5. Time of Joseph Lister
Carbolisation
In 1860 JOSEPH LISTER first identified airborne bacteria.
He used Carbolic acid spray in surgical areas to reduce
infections.
In 1880 JOHNSON & JOHNSON introduced antiseptic surgical
dressings.
LISTER ERA started the concept of Safe Surgical Procedures.
Carbolic acid decontamination reduced the incidence of
Hospital acquired infections thereby reducing mortality and

6. Why is Sterilisation Needed
More of at risk patients are operated.
No concept of cancellation of surgery nowadays, only
optimisation as per the patient’s health condition.
Two important factors
1.To prevent Surgical site infections . (SSI)
2.To prevent infections to Health care Workers.
WHAT IS DISINFECTION?
A process that eliminates many or all pathogenic micro
organisms except bacterial spores on inanimate objects.
WHAT IS STERILISATION?
A process that destroys or eliminate all forms of microbial life
including spores and is carried out in health care facilities by
physical or chemical methods.

7. SSI
Second common cause of HOSPITAL ACQUIRED INFECTIONS.( In around 5% of patients
undergoing surgery) BUT PREVENTABLE.
The Source of SSI can be
1.Endogenous-from patient’s skin,mucous membrane& hollow viscera.
2. Exogenous- from operating room environment,Surgical personnel,air,Instruments &
Equipments.(Implants,Prosthetic devices)
BY STERILISATION MAJOR PART OF
EXOGENOUS INFECTIONS
CAN BE CONTROLLED,
TO REDUCE MORBIDITY & MORTALITY.

8. Basic principles
1. Patient care-To Reduce SSI-part preparation,
antibiotics at the stipulated time,prevent sepsis in
invasive procedures done in the ward.
follow protocols strictly.(INFECTION CONTROL POLICY)
2. Theater care- Overall OR maintenance, care of
equipment and OR Instruments.
3. Care of Theater personnel- Scrubs, PPE, hand
washing & following the standard protocol with out
fail.

9. Basic Principles
CLEANING-done first. removes dust, contaminants and
organic matter. BROOMS NOT TO BE USED AT ALL.
VACUUM CLEANING & WET CLEANING PREFERRED.
DISINFECTION Reduces number of microbes.
STERILISATION is ABSOLUTE. Removes microbes and
spores.

10. OT INFRA STRUCTURE
OT Complex divided in to FOUR areas, Colour coded for easy
identification.
ZONE 1 PROTECTIVE AREA reception ,waiting, trolley bay,
Changing room, stores record room & class room
ZONE 2 CLEAN AREA pre op area, post op area, staff lounge
& sterile set room
ZONE 3 STERILE AREA operation theater, scrub room &
procedure room
ZONE 4 DISPOSAL AREA Dirty utility, disposal area corridor
leading to disposal zone

11. Operation room design
Modular OT especially for Ortho, Neuro, Cardio thoracic & Transplant OT.
The air flow is laminar with air changes of 25 times per hour & a lower ambient
temperature.(Horizontal or vertical,with antibiotics reduce SSI to 0.8%)
All Operation rooms to have sliding doors.
Limit personnel inside the room.
Clean cases like joint replacement surgery as first case.
Enter the Operation theater in sterile scrubs. use PPE as advised.
FOLLOW STANDARD PROTOCOLS STRICTLY

12. HVAC system
Most of the OTs would be served by a Heating, Ventilating, Air Conditioning (HVAC)
system that would be of a recirculatory type, wherein the air from the OT is taken back
to the air handling unit (AHU) for thermal conditioning and brought back.

13. Air flow in the OR
 Controlled air conditioning is ideal with a positively pressurised air.
 Hepa filter of 0.3 µm is used to minimise airborne contamination.
 Air filtration and air purification filters of 5 microns & 10 microns
filters with aluminium /SS frames are ideal.
 Floors,walls,skirting,corners and ceiling to be seamless.
 Surfaces to be hard but easy to clean.
 OR equipment cupboards to be with closed shelves.
 Anesthesia workstation/Boyles’ connected to dongles with monitors
on the shelves.
 Working space around OR table to be adequate.

14. Negative pressure OR concept
Was there in Septic OT & Isolation rooms.
Resurgence in Covid times. The negative pressure maintained inside
the OR, so that any micro organism is not blown out by the positive
air flow.
The outdoor air inlets must not be located near potential
contaminated sources like Lab exhaust & parking area.
WINDOW AND SPLIT ACS SHOULD NOT BE USED. They recirculate
and have areas that cannot be sealed. microbes can grow in those
areas.

15. Air change per hour should be 15-25 per hour, minimum 4 air
changes being fresh air component.
Air Velocity--The vertical unidirectional down flow of air on to
the OT table from the diffusers should be able to carry bacteria
away from the operating Table with a velocity of 20-25 feet per
minute. Clean to clean area movement of air.
Ambient temperature-20 to 23 degree centigrade.
Relative humidity-30 to 60 %

16. Cleaning schedules & disinfectants
Hand wash-chlorhexidine and povidine iodine scrub
Operating site-chlorhexidine, povidine Iodine solution.
Resusable equipment –in Cidex solution.
SCHEDULE
1. Operating room-daily, before 1st case, between surgery, at the End of the day.
IF THERE IS A SPILL DURING SURGERY .AND AFTER SURGERY IS OVER, ACCORDING
TO STANDARD PROTOCOLS.
2. Theater complex once a week.

17. FUMIGATION
prepare the fumigant as per manufacturer’s instructions.
Release the fumigant in to the OR.
Set time for fumigant to percolate and act.
Ventilate the space to make it safe.
Formalin was used before, it was an irritant& the OR has
to be closed for at least 12 hours.
Newer Non aldehyde compounds are available
nowadays.

18.  Bacillocid is Non irritant & provides asepsis within 30 to 60
minutes. OT need not be closed for 24 hours.
prior to fumigation
1. Cleaning room with detergent or carbolic acid not required
2. In between cases gather and segregate linen
3. Wash instruments & dispose the disposables
4. Clean floor around OT table
5. Disinfect work surfaces
6. Then fumigate
Fumigation protocols

19. Newer fumigants
1) Bacillocid
2) Vircon-Virucidal and fungicidal too
3) Ultrasol-Non glutaraldehyde compound. sodium percabonate peroxy hydrate.
used at our Hospital.
4) Envodil is silver nitrate & hydrogen peroxide combination. marketed as environment friendly,
non toxic and rapidly acting fumigant.

20. Anesthesia equipment
Pipelines – 1.outside OR cleaned and disinfected once in 6 months or
one year according to installer protocol.
2. Inside OT cleaned daily with disinfectant at the end of the day.
For every patient, change the linen on the work station/Boyles’
machine.
Always use PPE.
Be cautious of needle stick injury- if it happens, immediately wash
with water. report the incident. then follow the standard protocol of
treatment.
Change syringes after every case.
Use disposables whenever possible, sterilise reusables properly.

21. Maintenance of Sterilisation
 During non operational hours maintain positive pressure inside OR
 Air blower to be operational 24 hours
 Biomedical & electrical personnel to be available 24 hours for service
 Cleaning of filters done every 15 days
 Get validation as per ISO 14664 standards
 Air particulate count, temperature and humidity chart maintenance
is mandatory
 Swab taking & reporting by microbiology department standards

22. S.Aureus, Enterobactericea, Pseudomonas and aspergillus should never be
detected.
National Institute for Occupational Safety and Prevention 2009 guidelines are
followed.
Swabbing sites in OR
1. Upper surface of OT Table& 7. Floor on either side of OT table
2. Lower glass surface of OT light
3. Any 2 walls from any location above OT table height
4. Surface of sterile instrument trolley
5. Air condtion outlet
6. Anesthesia machine-medication kept area
Infection control measures

23. Air Sampling as per need.
Index of microbial air contamination to check colony count.
Report SSI to infection control committee and follow microbiology standard of
infection control measures.
DID YOU KNOW
Each person emits air particles 10k cfu/mt at rest and 50k cfu/mt after activity
in scrubs mask and cap 140-830cfu/mt.1 in 1000 particle is viable.
Remember 4-5 micron size is the smallest particle that can carry bacteria.
Infection control measures

24.  OT water supply also has to be disinfected.
 High temperature flushing of each outlet progressively at water
temperature of 160 degrees, for 5 minutes and High chlorination is
used.
 Maintain water pH at 7.0 to 8.0.
 Chlorination at 20-50ppm.
Disinfection of water

25. Sterilisation after operation on a covid + patient
• There should be one hour time between two cases to allow OT staff to send the patient back to the ward, conduct
thorough decontamination of all surfaces, screens, keyboard, cables, monitors, anaesthesia machine, etc.
• All floors and walls to be cleaned with 1% sodium hypochlorite solution before decontamination with hydrogen
peroxide spray,1% sodium hypochlorite solution & 75% alcohol.
• The staff has to remove the outer hand gloves. Discard surgical linen, dressing, breathing circuit, mask, tracheal
tube, HME filters, gas sampling line and soda lime after every surgery. Change water trap if it becomes
potentially contaminated.

26.  All unused items on the drug tray and airway trolley should be discarded. Seal all used airway equipment in a double zip-locked
plastic bag & then remove for decontamination and disinfection.
 The histo-pathological specimens are to be kept in tight fit plastic boxes which are then sealed in plastic bags. The plastic bags
are then wiped clean before sending for examination. The metallic equipment to be kept in 1% sodium hypochlorite solution for
half an hour,then washed and wiped clean. They are subsequently put in instrument boxes and covered with plastic bags.
 All the equipment being sent to Central Sterile Supply Department (CSSD) should be covered by plastic bags which should be
clearly labeled. All such equipment should be sterilized in a dedicated area and should not be mixed with OT equipment from
non-COVID areas of the hospital. It is preferable to have an autoclave machine/CSSD near the COVID OT. surfaces of passage
ways and the elevator should also be cleaned with sodium hypochlorite and alcohol.

27. • Anesthesia syringes, used gloves, empty drug vials/ampoules to
be discarded correctly after each surgery.
• Verify antibiotic given at preop area to the patient.
• Use disinfectants judiciously.
• For Spinal or other invasive procedures no shortcuts.
• use full Protocol of sterilising the work station, monitors,
pipelines & cylinders.
Anesthesia machine Check list for sterilisation

28. Bio medical Waste
 Medical waste is hazardous.
 Segregation of waste is colour coded.
 After every surgery is over the waste is put in to the appropriate
colour code covers & sent to collection area.
 Dedicated area is to be there for collection.
 Collection area should be easily accessible.

30. Points to remember
• Remember that we , the OR team have to take care of ourselves.
• We have to take Immunizations regularly & shouldn’t ignore needle stick injuries.
• Follow the Guidelines formed by your Hospital infection control team.
• Educate Staff on newer guidelines & keep updating our knowledge about newer advances.
• OR sterilisation maintenance is the responsibility of everyone
of the team.
.Team effort is the main component to provide the best quality of care.

31. Soap , water & common sense
yet the best antiseptic
William Osler
In Conclusion

32. References
1.Text book of Anaesthesia Equipments by Dorsch & Dorsch
2.Text book of Anaesthesia Equipments by Ward
3.Write up on theater sterilisation by Dr.T.V.Rao,HOD of Dept of Microbiology, Kollam,Kerala
4.Operating theatre quality and prevention of surgical site infections Review
J PREV MED HYC 2013 54;131-137 Spagnolo et al
5.Cleaning the operation theatre jceh 34 111 025
6. Operation theatres and sterilization requirements
design considerations and standards for infection control Review article