Do We Need Fumigation In Our

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Do We Need Fumigation In Our Indian
Operation Theatres?? - Dr.
Ajita Mehta President HIS-I
Consultant Microbiologist
P. D. Hinduja National Hospital MRC
Veer Savarkar Marg, Mahim (West)
Mumbai 400 016
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• Points to be discussed
• Critical Parameters for ideal Operation Theatre
  (OT)
• Indian Scenario about OT
• What is Fumigation / Fogging
• Do we need fumigation in India?
• What will be the Take Home Message?

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• Critical parameters for OT
• Filter air through 2 layer beds in series
• (efficiency of the 1st filter bed being gt30
  that of the 2nd
• filter bed being gt90)
• HEPA filters (to remove gt 0.3 ?m with an
  efficiency of 99.97)
• Positive pressure
• Requirement of 15-20 air changes /hour with a
• minimum of 3 air changes of fresh air (20).
• Air should flow from the ceiling be
  exhausted
• near the floor

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• Temperature of 20- 220C, is comfortable
  inhibits
• bacterial growth
• Relative humidity 30-60 to slow down bacterial
• growth
• Laminar airflow (ultra clean air) UV
  radiation
• have been suggested as additional measures
  in
• certain situations (orthopedic operations)

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• Heating Ventilation Air Conditioning (HVAC)
  Systems
• HVAC system maintain indoor air temp.
  humidity,
• control odours, remove contaminated air
  minimize
• the risk of transmission of airborne
  microorganisms
• Consists of air inlets, filter beds, humidity
  modification
• mechanisms, heating cooling equipment, fan
  ducts
• air exhausts

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• Fumigation is no longer used in the Western
  Literature
• as they have all the modern critical
  parameters required
• for OT

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• Indian Scenario
• In India, there are extreme situations in
  operation
• theater (OT) facilities, ranging from rooms
  with fans,
• window air conditioning, to the more
  sophisticated
• laminar airflow systems
• More than 60-80 of OTs, donot have air handling
  
• unit (AHU) other modern facilities with
  critical
• parameters
• In hospitals that lack heat ventilation air
  conditioning
• (HVAC) systems the quality of air in the OT
  cannot
• be guaranteed
• What can we do in such circumstances??

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• Fogging
• Nebulization of a disinfectant to decontaminate
  rooms
• vacated by patients with communicable
  diseases.

The origin of fogging can be traced to the 19th
century when Lister aerosolized carbolic acid to
improve antisepsis in operative practice
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• What Is Fumigation?
• Fumigation consisted of a mixture of formalin
  (280
• ml) and potassium permanganate (150 gm) being
• placed in a bowl. The room would then be
  sealed
• opened 12-24 hours later. Later on this
  changed
• formalin being sprayed with humidification by
  a
• spraying device or automist.
• Temperature 180C Humidity should be maintained
  to 600C

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Different Methods 1. Carboxyl acid fumigation
with Formaldehyde Advantages Established age
old technique Cost
effective Disadvantages a. Carboxylic acid
has efficacy as
scouring and disinfecting agent
b. Time consuming, min 24 hrs
turn around
time c. Self
defeating OT fumigated with
Formaldehyde needs to be force
de-aired with
unclean air d.
Unsafe Formaldehyde is carcinogenic
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2. Aldehyde based germicides Glutaraldehyde
formaldehyde (200 ml in 10 liters of water i.e
2) through fogging machine is the commonly used
procedure. Advantages- Effective Disadvantag
es a. Leaves sticky residue because of
surfactant base
b. Self defeating OT
fumigated with
Formaldehyde needs to be
force de-aired with unclean air
c. Unsafe- Formaldehyde has
been identified
as a carcinogen
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• Silver (Ag) and Hydrogen Peroxide (H2O2)
• Advantages a. Has deep penetrating
  capability
• b. Has no known
  resistant strains
• c. Effective against
  Bacteria, Viruses,
• Mycobacteria,
  Amoeba, Fungi and
• spore forming
  organisms

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A fogging system Droplets7microns thrust by a
motor running at 20,000 RPM to a distance of 15
m Solution Ecoshield 11 Hydrogen Peroxide and
0.01 dilute sliver nitrate
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• Efficacy of Fumigation / Fogging method
• Viable bacteria may fail to grow when cultured
  in the
• presence of disinfectants
• Neutralization of disinfectant (ammonia vapours
  or water)
• is must before collecting air samples or
  swabs
• Lecithin Tween 80 in appropriate
  concentrations
• are suitable neutralizing agents
• Environmental contaminants are generally
  associated
• with organic residues that bind deactivate
  most
• disinfectants, (least likely to be benefit in
  those areas contaminated
• with organic materials such as blood, feces
  or pus)

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• Fogging hastens the process of setting of
  airborne
• microorganisms. Mist, generated by a
  disinfectant or
• water would achieve the same process
• Air sampling is useful to detect aerosols or
  particles of
• microorganisms. (requires particle counter
  practical method for
• evaluating efficiency of filters)

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Air sampler
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• The Unresolved issues of microbiologic sampling
  are
• Lack of standards
• Lack of Standard protocols for testing
• Sensitivity of sampler used
• Such sampling should largely be reserved for
• epidemiological investigations during outbreaks

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• No studies to demonstrate that fogging actually
  reduces
• the incidence of nosocomial infection. The
  role of
• contaminated environmental surfaces in
  causing
• nosocomial infection remains to be elucidated
• Controlled studies at CDC have demonstrated that
  
• quaternary ammonium fog does not produce a
  significant
• (one log )reduction in bacterial counts of S.
  aureus or
• E. coli, even in areas in completely
  saturated with residual
• disinfectant
• CDC National Nosocomial Infections Study
  Quaterly Report, Third Quarter. 1971 isuued May
  1972)

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• In India, studies have not compared standard
  cleaning
• practices with fumigation/fogging.
• No substitute for vigorous scrubbing, washing of
  surfaces
• removing the organic matter
• Safety of repeated exposure of humans to
  disinfectant
• fog has not been established
• Inspite of these drawbacks it is the best
  alternative for
• - litigation
• - good safe hospital practices,
• - check up of human default
• - favourable psychological effect on staff
  patients
• - to improve the standard of hospital hygiene
  asepsis

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• Points to support
• Significant reduction in the number of bacteria
  in the
• ambient air
• Effective decontamination of exposed
  environmental
• surfaces
• Decreased risk of infection for housekeeping
  personnel
• engaged in terminal cleaning
• Decreased housekeeping costs
• Secondary psychological benefits for hospital
  personnel

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• Take Home Message
• Fumigation is the only alternative however
  following
• precautions should be taken
• Replace formalin with a safer agent like a H2O2
  stabilized
• with a silver salt
• It has no role in OTs with modern day HAVCs
• For litigation after fogging do the air
  sampling keep the
• record
• This is not an alternative to mechanical
  cleaning of surfaces
• If surgeries are being performed with window
  air-
• conditioners fogging would be required on a
  daily basis
• not on weekends alone as is practiced (WHO
  guidelines on
• prevention control of Hospital Associated
  infections SEA-HLM-343. Jan 2002)

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THANK YOU!