This document discusses sterilization and maintaining a sterile environment in operating theatres. It covers the history of sterilization practices dating back to Joseph Lister in the 1800s. It also discusses the importance of proper ventilation, sources of infectious agents, and different ventilation systems used in operating rooms. Further, it summarizes various sterilization methods like fumigation using formaldehyde and newer non-toxic compounds. The roles and best practices of the central sterile supply department and microbiology department are also highlighted.

1. Operation Theatre -
STERILIZATION
Presenter – Dr. Sukumar.T.K.

2.  Freeing of an article from all living organisms
including viable spores.
 Process that kills more than 106 organisms , including
spores of a defined exceptionally high degree of
resistance.
Sterilization

3.  1867 – Dr. Lister Joseph, identifies airborne bacteria.
Uses carbolic acid spray in surgical areas.
 1880 – Johnson and Johnson introduce antiseptic
surgical dressings.
 Use of Carbolic acid reduced Hospital associated
infections.
Safe Operation Theatre Practices –
The Beginning

4. Surgical Site Infections

8.  2nd most common cause of hospital acquired
infections.
 Mortality as high as – 77% .
 Sources –
 Endogenous
 Exogenous
 Maintaining sterile environment – control of major
part of exogenous infections
Surgical Site Infection

9. Operating Room Environment
 Ventilation
 Dust, lint, skin squames, respiratory droplets.
 Microbial level ∝ Number of people moving in room.
 Operating room should be maintained at Positive
Pressure.
Sources of Infectious Agents in OT

10.  Types of Ventilation
 Mixing
 Parallel Flow –(Laminar Airflow)
a)Vertical Parallel Flow
b)Horizontal Parallel Flow

11. OP – Box Ventillation

12. Ventilation Systems
Mixing
Vertical Parallel Flow
Horizontal Parallel Flow

13.  All ventilation systems in hospital should have two filter
beds in series (first = ≥30% ; second = ≥90%) – Ultra clean
air.
 Laminar airflow and use of UV is suggested to reduce
SSI (velocity – 0.3-0.5µm/sec). Minimum of 12 cycles/hr
 Recirculated air passed through HEPA Filter.

14.  Environmental Surfaces
 Routine cleaning has to be performed.
 Cleaned after contact with blood or potentially
infectious material.
 Wet vacuuming to be performed after last operation of
day or night.

15.  Frequent cleaning of walls and roof - not needed.
 These areas should not be disturbed unnecessarily.
 Floors get contaminated quickly – Depends on
number of people present.
 Ceiling fans should not be used.
 Clean roof – when remodelling or accumulated good
amount of dust.
Roof, Floors and Walls

16.  1% of microbes present on floor are pathogenic.
 Simple detergent -
 reduces flora by 80%
 Addition of disinfectant –
 95%
 70% alcohol – Disinfectant.
contd.

18. Fumigation

19.  Formaldehyde vapour – Produced on low temp
heating.
 Vapour phase decontaminates the air / environment.
 Mechanism – alkylates amino acids and sulfydral
group of proteins and purine bases.
 Used widely to sterilize huge areas like operation
theatres INSPITE OF BEING HAZARDOUS as it is
cheap.
Fumigation

20.  Thoroughly clean windows, doors, floors and all
washable equipment with soap and water.
 Close windows and ventilators tightly.
 Switch off all lights, A/C and other electronic items.
 Calculate room size and required amount of
formaldehyde.
Fumigation - Procedure

21.  Electric Boiler Fumigation
 For 1000 cu.ft of ot – 500ml of formalin added in 1000ml
water In electric boiler.
 Boiler switched on and kept on for 45 min.
 Switched off without entering room.
Creating Formaldehyde

23.  Potassium permanganate method
 For 1000 cu.ft add 450gm KMno4 to 500mlof formalin.
 Seal room and leave it for 48hrs.
 Residual formaldehyde gas neutralised by using
ammonia. (3Hrs)

25. Ecofriendly, non toxic non irritating environmental
disinfectant.
Has bactericidal, virucidal, tuberculocidal, fungicidal
and sporicidal action.
Complex formulation of stabilised 11% w/v hydrogen
peroxide with 0.01% silver nitrate solution
Eco shield™ (Bio shield)

26.  Formaldehyde free.
 No residue.
 Glutaral 100mg/g, benzyl-C12-18-
alkyldimethylammonium chloride 60mg/g, didecyl-
dimethylammonium chloride 60mg/g.
 Wet wipe procedure.
Bacillocid rasant™

27.  Virkon
 Disinfects medical devices.
 Disinfects laboratory equipment.
 Decontaminate spillages with blood and body fluids.
 Replace autoclaving and saving time.
Newer non toxic compounds

28. Monitoring of hospital associated infections
 Training of health care workers
Investigations of outbreaks
Any technical lapses
Monitoring of staff health
Infection Control Programmes

29. Education of universal precautions
Advice on isolation of infectious patients
Waste disposal
Safe use of antibiotics
Contd..

31. Role of Microbiology Department
 Identifies pathogen
 Monitoring of antibiotic therapy
 Education on specimen collection
 Information on common antibiogram patterns
 Data on hospital infection
 Surveillance of hospital environment
 Counselling of hospital staff.

32.  Settle plate method
 Position, duration.
 Blood agar exposed for specified period and incubated
 Slit sampler method
 Very effective and highly sensitive.
 Fixed volume of air is sucked and counts made
Air surveillance

33.  Factors influencing –
i. Number of persons present
ii. Body movements
iii. Disturbances of clothing

34.  Counts vary on number of personnel present on given
area.
 Nature of procedures
 ONLY 1% ARE PATHOGENIC
 Presence of Staphylococcus aureus makes difference
Significant count??

35.  Detection of spores of Cl.tetani in ot – losing
relevance
 Routine testing for anaerobic spores not essential.
Anaerobic spores

37. AIMS
 To provide sterilized material from a central
department
 To alleviate the burden of work of the nursing
personnel
 To facilitate the wards to function smoothly
Central Sterile Services Department

38.  Receipt and delivery of equipment from all areas of
the hospital
 Supply of sterile materials for dressings and
procedures carried out in wards and departments
 Supply of operation theatres with the necessary
sterile instruments and linen
FUNCTIONS

39.  To disassemble, clean and check for proper function
of equipment, such as suction machines, feeding
pumps, i.v infusion pumps etc.
 To dry, wrap, bag and seal items in preparation for
sterilization

40.  CSSD can broadly be classified into two parts:
 Central Unit: Responsible for receiving dirty utilities,
cleaning, processing, sterilization, storage and supply.
 Peripheral Unit: Mainly responsible for DISTRIBUTION
to various areas
 TSSU (Theater Sterile Supply Unit)
PLANNING OF A CSSD

41.  TSSU: In large hospitals, where number of OTs
function, these have peripheral sterilization units
known as Theater Sterile & Supply Units. (TSSU)
 These work under high pressure and takes less time for
sterilization.
 Specially in hospitals, where the Central Unit does not
function round the clock.
PERIPHERAL UNIT

42.  Dressing set/ tray
 Suture removal set
 Suturing set
 Cut down tray
 Tracheostomy set
 Gloves(nowadays disposable)
ITEMS COMMONLY HANDLED BY
CSSD STORES

43.  HSG and CT set
 Lumbar puncture set
 Bone marrow/ liver/ kidney biopsy set
 Burn pack
 Intra costal drainage (ICD) procedure set

44.  Catheter set
 Tapping/Aspiration set

45. 1. Receiving used items
2. Cleaning
3. Packing
4. Sterilizing
5. Storing (temporary)
6. Distributing to user departments
Major Activities in CSSD

46. RECEIVE
DIRTY ITEMS
CLEANING &
DRYING
PACKAGING &
LABELLING
GLOVERS, DRIP
SET
RUBBER GOODS
SYRINGES ,LINENS
GAUZE,COTTON
INSTRUMENTS
ETO
GAMMA
RADIATION
HEAT
DRY/ MOIST
CHEMICAL
STERILIZATIO
STERILE
STORAGE
DISTRIBUTION

47.  Should have access to outside through a window with
a counter.
 The items (especially for instruments in trays) are
counted and received.
 Instruments are inspected and blunt/unsuitable
instruments are segregated/ discarded.
 Necessary entries are made for records.
 Items shifted to cleaning area.
RECEIVING AREA

48.  Washing-Cleaning is the removal of visible soil (e.g.,
organic and inorganic material) from objects and
surfaces
 If used items are not decontaminated in user
department then blood/ body fluid soiled items
should be decontaminated with sodium hypochlorite
before handling further.
 Rinsing-Sorting-Soaking-Washing-Drying
CLEANING AREA

49.  Rinsing-Detergents (preferably enzymatic) &brushes
of various sizes and shapes are required in this area.
 Instruments washed either manually or in machines.
 For manual washing sinks with water supply and
working counters are organized

50.  Tunnel washer - highly sophisticated machine that
allow totally hand-off processing.
 Instruments coming from operating room or other
departments are placed into the tunnel washer
without any further handling. The instruments are
subjected to cycles washing, rinsing, ultrasonic
cleaning and drying.

51.  Ultrasonic washer is a machine used for cleaning
surgical instruments
 It converts high frequency sound waves into
mechanical vibration that produces small bubbles
that burst on the internal surfaces of instruments and
dislodge the waste particles.
 After the instruments are washed, they are dried in
oven dryer and shifted to packing area.

52. CATEGORY ITEMS PROCEDURE
Critical Enter tissue, through
which blood flows
Sterilization
Semi – Critical Touch mucous
membrane, touch non
intact skin
High level disinfection
Non – Critical Bandage, BP Cuffs Low level disinfection
Procedures Used

53.  High Temp – Steam Sterilization
 Low Temp – Ethylene Oxide gas, Hydrogen peroxide
gas plasma
Sterilization

54.  Liquid Immersion
 ≥2.4% Glutaraldehyde for 10hrs
 1.12% Glutaraldehyde and 1.93% phenol for 12 hrs
 7.35%hydrogen peroxide and 0.23%peracetic acid for
3hrs
 7.5% Hydrogen peroxide for 6hrs
 1.0% Hydrogen peroxide and 0.08% peracetic acid for
8hrs.
 ≥ 0.2% peracetic acid for 50 min at 50-56 degree Celsius

55.  Heat automated – Pasteurization for 50 min
 Liquid immersion
 2% glutaraldehyde for 20 – 45min
 0,55% ortho – pthalaldehyde for 12 min
 1.12% glutaraldehyde and 1.93% phenol for 20 min
 7.35% hydrogen peroxide and 0.23% paracetic acid for 15
min
 650 – 675 ppm chloride for 10 min
High level Disinfection

57.  The shelf life of the sterile materials depend on the
quality of packing materials used and the status of
cleanliness of storing area.
 Generally the items sterilized by steam autoclave can
be used for one week and ETO packs can be used for
6 months.
SHELF LIFE OF STERILIZED ITEMS

58.  Receipt register- to keep account of all the trays with
instruments received in CSSD
 Issue register to keep account of all the materials
issued to users
 Stock ledger of non consumable items- e.g. trays,
instruments
RECORDS

59.  Stock ledger of consumables- to keep account of the
cotton and gauze received, and issued by the CSSD
 Number of loads per machine per day
 Duty rosters of staff
 Log book of machine

60. Soap, Water and Common
Sense – Yet the best antiseptic
Importance of Hand Washing
WILLIAM OSLER

61.  VENTILATION SYSTEMS IN OPERATING THEATRES, ASPECTS TO
CONSIDER. A JOHNSON MEDICAL BULLET IN (REPUBLISHED
2002)
 Operating theatre commissioning -Microbiological From HICSIG
 Guidelines for prevention of hospital acquired infections. Yatin
Mehta, Abhinav Gupta, etal.
 Guideline for Prevention of Surgical Site Infection, 1999. Alicia J,
Teresa C, etal
Reference

62.  Recommendations for Infection Control for the
Practice of Anaesthesiology. Developed by the ASA
Committee Occupational Health Task Force on
Infection Control.
 Procedure-associated Module SSI – CDC
 OT Sterilization. T V Rao
 Text book of microbiology Mackie and McCartney-14th
edition.

63. THANK YOU