Current Trends in Sterilisation of Operation Theatres TOPIC INITIATED BY Dr.T.V.Rao MD Professor of Microbiology in Docplexus

1. Current Trends in Sterilisation of Operation Theatres
TOPIC INITIATED BY Dr.T.V.Rao MD Professor of Microbiology in Docplexus
A topic of interest to many wider contributions from Many Microbiology and Medical Professionals
from several Institutes globally
Time to end fumigation of operation theaters look for better alternatives.
Fumigation aims to create an environment, which will contain an effective concentration of fumigant
gas at a given temperature, for a sufficient period of time to kill any live infestations. Fumigation is
obsolete in many developed nations in view of toxic nature of Formalin. Too frequent use and
inhalation are hazardous. Several new safe chemicals are emerging but the constraint of economy
limits the use and several hours of closure of operation theaters can be curtailed as with fumigation.
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 practice of using
formaldehyde. A chemical compound which is multi-purpose disinfectant is gaining importance as a
non-aldehyde compound. Sodium dodecyl benzene sulfonate is proved to be a safe virucidal,
bactericidal, and fungicidal, mycobactericidal and non-toxic compound. It contains ozone (potassium
peroxymonosulphate), sodium dodecyl benzenesulfonate, sulphuric acid; and inorganic buffers. It is
typically used for cleaning up hazardous spills, disinfecting surfaces and soaking equipment. Though
sodium dodecyl benzene sulfonate is shown to have a wide spectrum of activity against viruses,
some fungi, and bacteria. However, it is less effective against spores and fungi than some alternative
disinfectants. Several other compounds are emerging in the Market for safer use, may need better
resources for utility and implementation. Which is the best method for sterilization of operation
theaters and why?
Contributed by Dr. A. Kumar
MBBS, MD, FMMC, Fellowship in Infection Control
Thank you Dr. Rao for bringing the topic for discussion. In fact the current Centres for Disease
Control, Atlanta, Georgia, USA, doesn't recommend for routine fumigation with any of the available
disinfectants. The operating theaters are not classified any more for clean and dirty infected surgical
procedures. If adequate terminal cleaning is performed any operating room can be used for any kind
of surgery. During our internship we used to have septic theaters for handling dirty/infected
operative procedures. Here, we currently operate even transplant surgical procedures following an
abdominal lapartatomy procedure as well but after adequate terminal cleaning. For cleaning &
disinfection of the operating room, the right disinfectant is chosen and is usually done with infection
control committee consultation & we currently use Clorox solution which is diluted to 40% and if
there is obvious spill of blood or body fluids we disinfect with 10% Clorox solution or we could even
use any of the quaternary ammonium compounds viz. present tablets 4 tablets in 5 litres of potable
water. Each tablet contains 250mgm quarterly ammonium compound. This product approved
environmental protection agency (EPA). This disinfection procedure takes just around 25-30 minutes
before a new patient is taken in. the most important thing to be remembered is that right
disinfectant is chosen and right contact time is observed before cleaning is performed. The mops
used for these cleaning process should be frequently changed and if a known infected patient is
operated, colour coded single use mop heads are used. But, if at all a patient following road traffic
accident is brought into the OR, where during evaluation, you find that the patient is diagnosed with

2. an airborne infectious disease such as open pulmonary tuberculosis, or a chicken pox with florid
lesions, we make sure we use disinfection with fumigation machine available from Johnson &
Johnson (USA) now take over by the French company & this machine uses calculated amount of
hydrogen peroxide mixed with silver ions and this destroys aerosols suspended in air. This procedure
takes around 30-45 minutes and this product doesn't damage any of the electronic devices and
doesn't leave any residual toxic chemical following the procedure. Of course this fumigation process
is initiated after thorough terminal cleaning. This product destroys even spores as per the
manufacturer's report. we do face increasing number of patients affected with Middle Eastern
Respiratory Syndrome Coronavirus (MERS-CoV) & we utilize this fumigation process with good effect
and this product has prevented occurrence of cross infection among patients with MERS-CoV as it
was evident that after patient discharge from a room, this virus lives in the aerosol for almost 36
hours even after terminal cleaning.
In addition, it’s mandatory for having all the environmental and engineering controls in place to have
a safe operating room for handling surgical procedures.
Restricted entry of unwarranted staff to the OR. Colour coded zone line demarcation for permitting
staff with street dress and recommendation to change to the OR dress code beyond the red line.
Always keep the OR closed during surgical procedure
Make sure that the OR is continuously monitored electronically for positive air pressure (> 18 air
exchange / hour).
Keep equipment’s and machines necessary only for the designated surgical procedure. because
many times we have noticed that c arm machines, operating microscopes for a neurosurgical
procedure or an ENT procedure will be kept in the OR during an unrelated procedure. If kept
unrelated to the procedure, these unused machines could get colonized from infectious aerosols and
if not adequately disinfected as per the manufacturer’s recommendation cross infection could occur
between patients.
Many at times, we have noticed that the exhaust vents within the OR would be obstructed by the OR
nursing staff without realizing the importance of the vent.
Always perform surveillance for surgical site infections for all surgical procedures performed and if
you find a cluster of patients with surgical site infection with a similar organism and antibiogram will
warn that some kind of cross infection has occurred and needs immediate investigation. Even re-
admission of surgical patients will be a cause of concern for cross infection and surgical site infection
or even catheter associated urinary tract infection or hospital acquired pneumonia or even central
line associated blood stream infections.
So, it’s a team work where the OR chief should get involved in prevention of infections by working
closely with the hospital housekeeping staff, hospital engineering services who controls the
operating room air ventilation system, involve the hospital infection control team, and others as
needed.
The above team should be involved in the decision making before a disinfectant product is
purchased by the hospital management or authorities.
Dr. Polavaram Babu Surgery Paediatrics
Clorox is nothing but regular bleaching powder shall we this powder in diluted form thro' fumigator
for 20 minutes

3. Dr. A. Kumar
MBBS, MD, FMMC, Fellowship in Infection Control
Dr. Polavaram Babu No, there are Clorox concentrated liquid solutions dedicated for hospital
disinfection use. If needed you should procure this product only because there are many clorox
preparations for household unlabelled as perfumed preparations.
Dr. Pardeep Bhatia Orthopaedic
Is it available in India? What is trade name?
Dr. A. Kumar says
Dr. Pardeep Bhatia I am not sure about the availability but can try from vendors. The product is
manufactured in France. There was another company from USA -One of the well-known Indian
company has been merged with the French company & so currently the entire product is supplied
only by the French.
Dr. Kalaimani Kandaswamy Anaesthesiology
Thank you Dr.T.V.Rao & Dr.A.Kumar for their timely updates, but still needs more details as to the
products, its availability... But the OT team cannot lax in adopting strict sterile codes, dress......
Dr. Ajay Mehta Anaesthesiology
It is mandatory for soap and water cleansing and drying .then fumigation, minimal speaking and
movements, of course positive pressure and 18 air changes. - Changes, which is tricky for the
engineering Dept. hepa filters need changes frequently like in DELHI this adds to costs. We must do
that.
Dr. Usha Udgaonkar Microbiology
Nice and very useful write up Dr.T.V Rao and Dr.A Kumar. The word fumigation is no longer used. I
think it is fogging. Fumigation is used for pesticides spraying
Dr. Prabhu Prakash MD
Sir, really very informative post, but it’s very debatable and having long list of quarries by all
concern sp. OT In charge, Microbiologists and Administrators. Few days back there was media news
in our own----Due to increases Air Count {BCP) in OT ALL OT'S closed. Sir what is your opinion--- If
there is No Need of fogging -then should we go for OT Air Sampling by Plate Count Method.
Dr. A. Kumar
MBBS, MD, FMMC, Fellowship in Infection Control
Dr. Prabhu Prakash Normally, microbiological air sampling is done using a machine called as RCS
centrifugal air sampling where an agar strip is inserted into the machine through a socket and you
get inside the OR by wearing sterile protective gears and switch on the machine. During this process,
this machine will suck air in a calculated amount and if the air contains bacteria or fungi, it will get
stuck onto the agar strip. After 10 - 30 minutes of exposure, you can bring this trip to the
microbiology lab and incubate in an aerobic incubator at 37 degree centigrade. After 48 hours, 72
hours & 7 days, we can calculate the number of aerobic bacteria, saprophytic bacteria and

4. fungi/molds respectively. During this analysis, not more than 35 colony forming units should be
there on the agar strip to be considered safe for proceeding with surgical procedures in the tested
OR. But exceptions to this colony count is there. Even if certain organisms such as multi drug or pan
drug resistant bacteria of even a single colony or a fungi or molds would be considered unsafe for
operative procedures. if this error is identified, immediately the HVAC technician from the hospital
engineering services should be called upon for evaluation and check the positive air pressure along
with the air exchange rates. Normally a positive air pressure of more than or equal to atleast 18 /
hour need to be maintained for general surgical procedures. If orthopedic implant or neurosurgical
or cardiovascular or thoracic surgery is performed these Ors should have more than atlas 24 air
exchanges should be maintained. In addition the air filtering should be through various high
efficiency particulate filters (HEPA) and this should be changed if there is increase in microbiological
colony count on air sampling or if the air exchange rate is not achieved as per the recommendation.
Normally microbiological air sampling is performed when a new operating room is constructed or a
renovation is conducted. At times, if you notice that infectious outbreak is identified among patients
undergoing operative procedures, immediately stop the procedures within the OR, investigate the
cause and seek the help of hospital housekeeping services along with air ventilation uncharged and
sort or seek for issues. Once this is sorted out either by change of HEPA filters or ultra-pure filters
where 99.9% of microbes are filtered especially on transplant ORs you can again perform
microbiological air sampling. Based on the test results you can permit or deny permission for OR
team to perform procedures. Routine cleaning & disinfection of the OR doesn't warrant
microbiological air sampling. In addition, where resources is a limitation microbiological air sampling
could be done by using plain blood agar plate exposure under the Air condition vents with an
exposure time of 60 minutes and evaluate the results similar to the RCS sampling. Decision to
perform this procedure is always decided by the Infection control physician rather than the
operating room chief or other clinical colleagues. But clinical or surgical colleagues can always seek
for any help or even suggests for air sampling but final decision is done by the Infection control team
or the committee members. Resources should be always spent on scientific basis and not based on
wild guess. In addition, i would also suggest that the following parameters need to be recorded on a
daily basis for ORs. Daily positive air pressure along with electronic measurement of air exchange
rates (18-24/hour) with positive air pressure, humidity which is as well monitored electronically
maintained between 20-60%. OR temperature maintained between 18-22 degree centigrade which
is as well recorded electronically. In adding the air ventilation unit for the OR should be having its
own dedicated ventilation and not mixed throughout the hospital. ·
Dr. Usha Udgaonkar Microbiology
Thanks. For very useful information and equally useful discussion. I have always felt a thoroughly
vigorous soap water cleaning is the best. Fogging not required. For SSI one should distinguish
between infection in OR and ward infection. Usually, The OR infection is seen on 1st removal the
dressing whereas ward infection of SSI manifests later.
Dr. A. Kumar
Dr. Usha Udgaonkar i do agree that in normal circumstances, fogging or fumigation is not
recommended, but in our clinical situation where we do get lot of patients suffering from airborne
infectious diseases (e.g. open pulmonary tuberculosis, MERS-Coronavirus infections, at time we do
have patients with florid chicken pox lesions) & such patients if we had to take them for emergency
surgical procedures, following the operative procedures, we had to perform fumigation of the OR as
the ORs are aerosolised with the above viral or bacterial pathogens risking subsequent patients from

5. acquiring these infectious pathogens. Hence during these clinical situations, we do perform
fumigation with hydrogen peroxide mixed with silver ions which is available as a commercial liquid
form filled into a automatic machine which fumigates or foggy the entire OR. This process facilitates
the cracks and crevices of the OR to be thoroughly disinfected with the disinfectant or else our
regular terminal may not be able to disinfect these small cracks on the walls or corners or even the
exhaust vents and HEPA filter A/C vents cannot be disinfected.
Dr. Prabhu Prakash MD
sir recently we are having Klebsiella outbreak in NICU , should we go for fogging --rest all measures
we have taken care but still we are isolating Klebsiella from NICU
Dr. A. Kumar
MBBS, MD, FMMC, Fellowship in Infection Control
Dr. Prabhu Prakash Outbreak with Klebsiella pneumoniae outbreaks are known to occur in nurseries
and neonatal ICUs. Another common organism associated with NICU outbreak is with Enterobacter
species. We did have this outbreak in our own NICU few years back. Fogging is not recommended in
this situation as cross infection happens only through contact with contaminated hands of
healthcare providers, at time contaminated through contaminated breast pumps, milk storage
freezers and cold compartments, re-use of milk storage bottles, & other means. In this case, we do
recommend to discharge as many patients as possible if clinically stable. Stop new admissions in the
unit. Decontaminate all the medical devices as per the manufacturer’s recommendation &
document the same in a log book or checklist for verification. Perform adequate and appropriate
terminal cleaning using dedicated clean mops with adequate con tact time with the chemical used
for disinfection. Educate and implement appropriate hand hygiene at all times of patient contact, If
possible restrict the entry of visitors including parents & if not possible educate them for performing
adequate hand hygiene. If these simple and routine measures are implemented along with a
departmental meeting to create awareness among all health care providers of the paediatric & NICU
along with Obstetrics staff, i believe the outbreak could be controlled and stopped. Fumigation or
fogging is not recommended in this clinical situation.
Dr. T.V Rao MD
Major ideas are documented and converted into pdf for benefit of many the total document will be
posted if the email is sent doctortvrao@gmail.com I can be contacted on Mob no 8281669524 let all
be together make many contribution for improving the safety of the patients
Dr. Bharti K Anaesthesiology
Excellent information
Dr. Azam Nawaz MS, DNB URO
Very informative but some definite protocol should be standardized and guidelines issued
Make your best Contributions and make the partner in the desired change
All opinions are Individuals carries no conflict of Interest
Dr.T.V.Rao MD

6. Professor of Microbiology Freelance Microbiology reporter
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