AMH JOURNALS UK Publishes STERILIZATION OF OPERATING THEATRES by Dr.T.V.Rao MD Methods to replace fumigation By Dr.T.V.Rao MD is a Professor and Head of the Department of Microbiology at Travancore Medical College in Kollam, India Dr T V Rao is also a content provider on Medical Microbiology and Infectious Diseases for numerous international websites. Translated into 91 global languages for benefit many in the remote corners in the Developing countries Dr.T.V.Rao MD

1. January 2014 22
OPERATING THEATRE MANAGEMENT Prof T V Rao, Travancore Medical College
Despite the brief amount of time patients generally
spend in an operating theatre (OT), this is an
environment that plays a great role in the onset and
spread of infections.
It is usually necessary to study the epidemiology of infection
as a multidisciplinary approach. In resource poor
circumstances, prevalent in most developing countries,
people work in isolation and few facilities to make any
epidemiological surveys.
Many believe that routine microbiological monitoring is
essential but in reality it is not practicable. Every hospital
should, however, pay good attention to the proper
maintenance of air conditioning and ventilator systems, and to
having greater control of mechanisms and personnel involved
in the disinfection and sterilisation of materials used in the
theatres in operative procedures.
Sterilisation means eradicating germs completely, which is not
100% possible in an operating theatre. The sources of
bacterial contamination are from air and the environment,
infected body fluids, patients, articles, or equipment.
The following methods are practised to keep the operating
theatre bacteriologically safe and below accepted levels:
1. Special air flow pattern – this is such that filtered and
purified air circulates and contaminated air is removed
continuously. There is restriction of personnel traffic,
closing of OT doors and a good ventilation system.
2. Standard cleaning, disinfection with appropriate chemical
agents, good theatre practise and discipline can provide a
microbiologically safe environment.
Fumigation
Fumigation is an age old process of sterilising the environment
- a sick room or operating theatre, for example. It is done with
Formalin fumes, which are very pungent and harmful. When a
room is fumigated, it is tightly closed and sealed before
fumigation. The room is opened after fumigation,
12 to 24 hours later. The room can be used again once all the
fumes are out.
OSHA (Occupational Health and Safety Administration)
indicated that Formaldehyde should be handled in the
workplace as a potential carcinogen, and set an employee
exposure standard for Formaldehyde that limits an eight hour
time-weighted average exposure concentration of 0.75ppm.
STERILISATION OF OPERATING THEATRES
Methods to replace fumigation
Commercially available disinfectant Formaldehydes are the
most commonly used agents for high level disinfection of the
theatre environment. Formaldehyde gas is generated from
liquid formalin, utilising potassium permanganate crystals.
40% formalin liquid is added to potassium permanganate
crystals to generate the gas.
Alternately, formalin liquid can be dispersed by a sprayer like
device in the theatre environment. After a contact time of at
least six to eight hours, the Formaldehyde needs to be
neutralised by using ammonia, allowing at least two hours of
contact time for ammonia to neutralise the Formaldehyde prior
to the use of theatre.

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OPERATING THEATRE MANAGEMENT
How fumigation was done
1. Seal the room with adhesive tapes around the edges of the
doors/windows, ventilators and apertures.
2. For each 1,000 cu.ft of space place 500ml Formaldehyde
(40% solution) and 1,000ml of water in an electric boiler.
Switch on the boiler, leave the room and seal the door.
3. Seal the room for 24 hrs.
4. Open the door and neutralise any residual Formaldehyde
with ammonia by exposing 250ml of SG 880 ammonia/1L
of Formaldehyde used. (Ref - Mackie and McCartney
Practical Medical Microbiology 13th Edition). Fumigation is
obsolete in many developed nations in view of the toxic
nature of Formalin. Too frequent use and inhalation is
hazardous. Several new safe chemicals are emerging but
constrains of economy limit the practise of several hours of
closing an operating theatre for the purposes of fumigation.
Looking at alternatives
Aldehydes are potentially carcinogenic and it is therefore
recommended that other agents such as hydrogen peroxide,
hydrogen peroxide with silver nitrate, peracitic acid and
other chemical compounds of Formaldehyde should
be used in place of the currently prevalent practise
of using Formaldehyde.
These agents are dispersed with the aid of a fogger-like device
inside the theatre environment. The contact time is about an
hour and the theatre can be used immediately after this.
The following precautions have greatly reduced the rates
of infection:
1. Every hospital must establish an infection control committee
to monitor the events in the hospital on all matters related
to the control of infections.
2. The entry of unnecessary personnel should be restricted
into operation theatres as everyone potentially contributes
to infection.
3. A thorough washing with warm water and good detergent
can bring more of an overall improvement than solely
decontamination sterilisation with other chemicals,
or fumigation.
4. Frequent monitoring and training of medical and
paramedical staff must carry a high priority – don’t merely
observe mechanical and chemical methods.
5. Thorough washing and carbolisation, if done every day after
the surgeries, will greatly enhance the safety standards and
reduce the repeated expenditure on fumigation.
Some of the emerging compounds developed for use in the
sterilisation of operating theatres are more effective for
environmental decontamination, have a very good cost/benefit
ratio, good material compatibility, excellent cleaning properties
and leave virtually no residues. One particular product available
has the advantage of being a Formaldehyde-free disinfectant
cleaner with low use concentration. Its active ingredients are:
Glutaral 100 mg/g, benzyl-C12-18- alkyldimethylammonium
chlorides 60 mg/g, didecyldimethylammonium chloride
60 mg/g. 

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OPERATING THEATRE MANAGEMENT
Its advantages are:
• It provides complete asepsis within 30 to 60 minutes
• Cleaning with detergent or carbolic acid is not required
• Formalin fumigation is not required
• A shutdown of an OT for 24 hours is not required
Another chemical compound which has gained importance as
a non-Aldehyde compound is a multipurpose disinfectant
which contains oxone (potassium peroxymonosulphate),
sodium dodecylbenzenesulfonate, sulphamic acid and
inorganic buffers.
It is typically used for cleaning up hazardous spills, disinfecting
surfaces and soaking equipment. The solution is used in many
areas, including hospitals, laboratories, nursing homes, funeral
homes, medical, dental and veterinary facilities, and anywhere
else where control of pathogens is required.
This second product has a wide spectrum of activity against
viruses, some fungi, and bacteria but it is less effective against
spores and fungi than some alternative disinfectants.
Several other compounds are emerging in the market for safer
use, however.
A breadth of
considerations
Operating theatres should be built with implementation of
good civil engineering standards, which encompass
numerous elements.
1. Operating theatre discipline
• Only people absolutely needed for an assigned task should
be present in the operating theatres
• People present in theatre should make minimal movements
and curtail unnecessary movements in and out of theatres.
This will greatly reduce bacterial count
• Airborne contamination is usually affected by the type of
surgery and the quality of air, which in fact depends on the
rate of air exchange
• All the persons, including the least cadre of employers,
are partners in infection control and should be careful to
comply with infection control regulations
• Prompt disposal of theatre waste is a top priority.
Any spillage of body fluids, including blood on the floors,
is highly hazardous and prompts the rapid multiplication of
nosocomial pathogens – in particular, Pseudomonas spp
2. Surveillance of operating theatre
The environment in the operating theatre is dynamic and
subject to continuous change. Good infrastructures do not
mean a safe environment, as people in fact make a greater
impact by making the environment unsafe.
The role of microbiological surveillance is crucial,
and microbiologists should be aware of organisms, sites and
populations as surveillance cultures should be chosen carefully
to allow meaningful interpretation of results.
Microbiologists should be familiar with the clinical
techniques, as those normally used for culturing clinical
specimens may not yield correct results when applied to
environmental specimens.
Sites and cultured reports should not be chosen as etiological
sources in the present infections. Culturing unnecessary
surface areas causes confusion and meaningful interpretation
is lost.
3. Air as an infection source
Bacterial counts in operating theatres are influenced by the
number of individuals present, ventilation and air flow.
The results should be interpreted taking this into consideration.
Surveillance of air
borne pathogens
In resource poor hospitals settle plates with blood agar are
used and can detect pathogens, commensals and saprophytic
bacteria. Multiple plates are kept and results are based on
overall assessment rather than on a single plate study in the
room. Microbiologists will clarify the acceptable counts at the
different physical locations in multispecialty hospitals.

4. January 2014
There has been a sea change in the analysis of bacterial
counts in the recent past, with advances in medical
technologies such as joint replacement surgeries dealing with
critical patients.
Slit sampler and air centrifuge equipment for bacterial counts
are replacing settle plates. The safe level of colony counts can
be calculated as per the standards created with peer reviewed
studies by the manufacturers.
How frequently should we do the surveillance for air borne
microbes? There is no definite answer to this question.
Doing too frequent surveys is expensive and will not correlate
the existing infection rate in the hospital, but can indicate the
circumstance we operate which can have an effect if the
safety standards fall. Surveillance for Clostridia spores may
be needed.
The age old tradition of detection of anaerobic spores of
C.tetani, and gas gangrene producing organisms are losing
ground with the onset of more awareness on theatre
sterilisation. Routine testing for the anaerobes is not essential
except when there are suspected cases of Tetanus or gas
gangrene attributed to operating in a particular theatre.
Ideally you should survey the operating theatre for anaerobes
when newly constructed, or when any remodelling or structural
alterations are made.
General management
instructions
For the sterlisation and disinfection of operating theatres,
and critical care areas, there are certain protocols which
should be followed. These include:
1. Keep the floor dry when in use.
2. Use only vacuum cleaners – booming to be forbidden as it
will dispense the infected material all around and on
the equipment.
3. Chemical disinfection of an operation room floor is probably
unnecessary. The bacteria carrying particles already on the
floor are unlikely to reach an open wound in sufficient
numbers to cause an infection. Cleaning alone followed by
drying will considerably reduce bacterial population.
4. Walls and ceiling are rarely contaminated. The numbers of
bacteria do not appear to increase even if walls are not
cleaned. Frequent cleaning is not necessary and has little
influence on bacterial counts. Routine disinfection is
therefore unnecessary – only clean when dirty.
Cleaning the
opertaing theatre
At the beginning of the day
1. Only remove the dust with a cloth wetted with clean water.
Wipe theatre furniture lamps, sitting tables, trolley tops,
operation tables, procedure tables, and Boyle’s apparatus.
Note: You need not use chemicals/disinfectants unless
contaminated with blood or body fluids.
Between the procedures
Clean operating tables or contaminated surfaces with
disinfectant solutions.
1. In case of spillages of blood/body fluids decontaminate with
bleaching solution/chlorine solution (10% available chlorine).
2. Discard all waste in plastic bags (do not accumulate around
surgical sites).
3. Do not discard soiled linen and gowns on the operating
theatre floor.
At the end of the day
1. Clean all the table tops, sinks, door handles with detergent
followed by low level disinfectant.
2. Clean the floors with detergents mixed with warm water.
3. Finally, mop with disinfectant like phenol in the
concentration of one in ten (low concentrations of phenol
will not serve the purpose).
4. Keep the operating theatre dry for the next day's work
Training paramedical
staff
The short solution to controlling infection lies with trained staff.
The principle and control of infection to all newcomers and
junior staff should be an important goal for any
good institution.
Formulate a guidelines update as per the any changing
situations in the control of infection.
Institutes should formulate their ideas on infection control
based on varying circumstances, as there are no fixed control
guidelines or formulae to suit all occasions.
Simple, repeated hand washing is the most cost effective
method of reducing several infections in hospitals –
in particular in operating theatres. 
OPERATING THEATRE MANAGEMENT
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OPERATING THEATRE MANAGEMENT
Bibliography
1. Principles and Practice of Disinfection, Preservation and Sterilization, 3rd
edn. AD Russell, WB Hugo, GAJ Ayliffe, Eds. Blackwell Scientific Ltd,
Oxford, 1999. ISBN 063 2041 43.
2. Disinfection, sterilization and operation theater guidelines for
dermatosurgical practitioners in India Narendra Patwardhan1,
Uday Kelkar2 Year : 2011 | Volume : 77 | Issue : 1 | Page : 83-93.
3. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008,
William A. Rutala, PhD, M.P.H.1,2, David J Weber, MD, MPH1,2, and the
Healthcare Infection Control Practices Advisory Committee
(HICPAC)3 (CDC 2008).
4. Assessment of in-vitro efficacy of 1% Virkon against bacteria, fungi,
viruses and spores by means of AFNOR guidelines. Herńndez A, Martró
E, Matas L, Martín M, Ausina V. PMID 11073729 [PubMed - indexed for
MEDLINE].
5. Evaluation of in vitro efficacy of the disinfectant Virkon. Gasparini R, Pozzi
T, Magnelli R, Fatighenti D, Giotti E, Poliseno G, Pratelli M, Severini R,
Bonanni P, De Feo Eur J Epidemiol. 1995 Apr; 11(2):193-7.
Author
Dr T V Rao is a Professor and Head of the Department of
Microbiology at Travancore Medical College in
Kollam, India.
His work covers a wealth of areas, with research and
audit experience:
1. Associated with HIV/AIDS screening and research work
at Andhra Medical College, Visakhapatnam, 1990 – 91.
2. Associated with Dr TN Naik, PhD, Head of Virology National Institute of
Cholera and Enteric Diseases – Calcutta (ICMR) on study of Rotavirus
with technology developed at NICED – Calcutta – 1991.
3. Isolated 0 – 139 – Vibrio cholera at Sri Venkateswarara Institute of
Medical Sciences, Tirupati (AP). The strain was named as Tirupati strain
by National Institute of Cholera and Enteric Diseases Calcutta –
India (Under ICMR) – 1994.
4. Trained at Institute of Immuno Haematology at Indian Council of Medical
Research, Bombay on HLA; typing for establishing HLA Laboratory for
benefit of the patient undergoing renal and bone marrow Transplantation.
Papers published by Dr T V Rao include the following:
1. Emphysematous Pyelonephritis in diabetic keto acidosis –
Indian experience – The Indian Practitioner – January, 1997.
2. Bacteraemia in a tertiary care urban hospital in South India – The Indian
Journal of Pathology and Microbiology – July, 1999.
3. Bio informatics in future medicine, Drug Development and role of Doctor
– Voice of Medico – July, 2001.
In addition, publications in the last five years include:
1. Evaluation of different phenotypic methods for detection of Methicillin
Resistant Staphylococcus aureues in a tertiary care hospital - Journal of
the Academy of clinical microbiologists 2007, Vol 9, No 2
(original articles).
2. Salmonella Typhimuruim septicaemia manifesting as mono arthritis –
The journal of academy of clinical microbiologists – 2007, Vol 9 No 2
(Case Study).
3. Estimation of antibodies to Hbs Ag in vaccinated health care workers,
Indian Journal of medical microbiology, 2008, Vol 26 Issue
(Correspondence).
4. Prevalence of Rubella immunity in health care students, The Internet
Journal of Infectious Diseases, 2009, Vol 7 (original article).
5. A case of snake bite complicated by Morganella morganii subspecies,
morganii Bio group 1 infection, The Internet Journal of Infectious
Diseases 2008, Vol 6, No 2.
6. Onchomycosis due to Fusarium oxysoprum, The Internet Journal of
Infectious Diseases, 2009, Vol 7, No 2.
Dr T V Rao is also a content provider on Medical Microbiology and Infectious
Diseases for numerous international websites.
M: +919961785124, +918281669524
E: doctortvrao@gmail.com
W: www.medmicrobes
About Travancore Medical College,
Kollam, India
Our Department of Microbiology caters for the basic needs of the
multispecialty hospital, apart from teaching medical students attached to it.
Our main work includes bacteriology, and processing of clinical samples for
detection of infectious agents. We document the results in WHONET
software, and periodically analyse the Antibiograms. We do hospital
surveillance for environmental biosafety and several tests in virology to cater
to the immediate needs of both inpatients and outpatients. We train several
postgraduates in Diagnostic Microbiology on dissertations and thesis work.
I am supported in the department by Dr Mary Mathews MD Professor;
Mrs Deepa Babin MSc, Assistant Professor; Mr Sreenath MSc, Lecturer; and
Mrs Nusaifa and Mrs Muniba and Mrs Magitha with technical assistance.