STERILIZATION PRACTICES FROM PAST TO FUTURE NEEDS by T.V.Rao MD

STERILIZATION PRACTICES FROM
PAST TO FUTURE NEEDS
Dr.T.V.Rao MD
8/15/2021 Dr.T.V.Rao MD @ Streilization for futture needs 1

Beginning of Safe Operation Theatre
Practices
•1867 –Dr.Joseph Lister
first identifies airborne
bacteria and uses
Carbolic acid spray in
surgical areas
•1880 – Johnson and
Johnson introduce
antiseptic surgical
dressings.
Dr.T.V.Rao MD @ Streilization for futture needs 2
8/15/2021

Infections are a great threat to any patient
HOW SAFE ARE OUR HOSPITLAS
• Hospital-acquired infections
can develop, which can
create a whole new set of
problems for patients.
According to the Centers for
Disease Control and
Prevention, hospital-
acquired infections are an
often-preventable threat to
a patient’s health and
overall survival.

Hospital associated infections
• According to CDC, about one in 25 patients have a
hospital-acquired infection. There are various types
of hospital-associated infections, such as central line
infections, catheter-associated urinary tract
infections, surgical site infections and ventilator-
associated pneumonia. The cause of hospital-
acquired infections also varies, but some common
diseases include the following:

Ramifications of Hospital-Acquired Infections
• Longer hospital stays: People who develop hospital- acquired infections
often require longer hospital stays. Longer stays put patients at an even
higher rate for developing more complications.
• Increased costs: Longer hospital stays also means more treatment and
more costs. The CDC estimates that annually hospital-acquired infections
cost patients over ten billion dollars.
• Lost wages: Hospital associated infections can lengthen recovery time
and prevent you from returning to work, resulting in lost wages.
• Death: In some cases, hospital-acquired infections can be fatal. According
to the Alliance for Aging Research, in the United States, about 99,000
people die every year due to hospital-acquired infections.

Figure 9.2 Relative susceptibilities of microbes to antimicrobial agents

Sterile Environment reduces
Surgical site infections.
• SSI are the second most
common cause of hospital
acquired (Nosocomial)
infections. These
complications of surgical
procedures cause
considerable morbidity
and, when these occur
deep at the site of the
procedure, can lead to
mortality as high as 77%.
8/15/2021

Basic Principles
•Cleaning more Important
than Disinfection and
Sterilization ?
• However
• Cleaning
Removes contaminants,
Dust, organic matter,
Disinfection
Reduces number of
Microbesof microbes
8/15/2021

Basic care of Operation Theatres.
• Reduction of Microbial counts is
important.
• Very rarely the Microbes reach
the operation site,
• Paying great attention to Floors
Using unnecessary, too many
chemical not necessary
• Keep the floor Clean and Dry -
Bacteria are reduced,
• Most Important component of
Bacteria is water a dry areas causes
natural death except spores
8/15/2021

Frequent cleaning of Walls and Roof of
Operation Theatre is not needed
• Frequent cleaning has little
effect.
• Do not disturb these areas
unnecessarily,
• Floors get contaminated quickly,
depend on
Number of persons present in
the
Theatre / Movements they
make, has direct relation to
increase of bacterial counts
8/15/2021

Do not disturb the Roof
•Do not disturb
unnecessarily,
•Do not use ceiling fans
they cause aerosol spread
•Clean only when
remodeling or
accumulated ,good
amount of dust.
8/15/2021

How you care for Floors
•Use only vacuum
cleaners
•Don't broom
•As it increases the
bacterial flora in the
environment
8/15/2021

Cleaning the Floor
•A simple detergent
reduces flora by 80 %
•Addition of
disinfectant reduces
to 95 %
•In busy Hospitals
counts raise in 2
hours Dr.T.V.Rao MD @ Streilization for futture needs 13
8/15/2021

Environmental Cleaning of
Operation Theatres
• Do not waste chemicals.
• Only remove the dust with
cloth wetted with clean
water,
• Don't use
chemicals/Disinfectants as
a habit,
• Use only when
contaminated with blood
or body fluids.
8/15/2021

Handling of Air in Operation
theatre.
•Negative Air
pressure vented to
the operation
theatre.
•Environmental
cleaning should be
twice daily
8/15/2021

Fumigation
a biohazard procedure ?
Still We do it
8/15/2021

Fumigation
•Formaldehyde a Age old compound.
•Low temp heating produce vapor
•Vapor phase decontaminates the air/environment.
•Kills vegetative bacteria / Spore ?
•When Formaldehyde mixed with water and exposed
to elevated temperature
•Gaseous formaldehyde is generated
Time X Temp
8/15/2021

Procedure of Fumigation
• Thoroughly clean windows, doors, floor,
walls and all washable equipment's with
soap and water.
• Close windows and ventilators tightly. If any
openings found seal it with cellophane tape
or other material.
• Switch off all lights, A/C and other electrical
& electronic items
• Calculate the room size in cubic feet (L×B×H)
and calculate the required amount of
formaldehyde as given in
8/15/2021

Creating the Formaldehyde gas
• Electric Boiler Fumigation
Method: For Each 1000 cu.ft of
the volume of the operation
theatre 500ml of formaldehyde
(40% solution) added in 1000ml
of water in an electric boiler.
Switch on the boiler, leave the
room and seal the door. After
45 minutes (variable depending
to volume present in the boils
apparatus) switch off the boiler
without entering in to the room
.
8/15/2021

Adding Potassium Permanganate to
formaldehyde..
• Potassium Permanganate Method: For every 1000
cubic feet add 450gm of Potassium permanganate
(KMnO4) to 500 ml of formaldehyde (40%
solution). Take about 5 to 8 bowels (heat resistant;
place it in various locations) with equally divided
parts of formaldehyde and add equally divided
KMnO4 to each bowel. This will cause auto boiling
and generate fume.
• After the initiation of formaldehyde vapor,
immediately leave the room and seal it for at least
48 hours. Dr.T.V.Rao MD @ Streilization for futture needs 20
8/15/2021

Fumigation to be neutralized
• Neutralize Residual formalin
gas with Ammonia by
exposing 250 ml of Ammonia
per liter of Formaldehyde
used.
• Place the ammonia solution
in the centre of the room and
leave it for 3 hours to
neutralize the formalin vapor
8/15/2021

An example is set as..
• Operation Theatre Volume = L×B×H =
20 × 15 × 10 = 3000 cubic feet
• Formaldehyde required for
fumigation = 500 ml for 1000 cubic
feet
• = So 1500 ml of formaldehyde
required
• Ammonia required for neutralization
= 150ml of 10% ammonia for 500 ml
of formaldehyde
• = So 450 ml of 10% ammonia require
8/15/2021

Formaldehyde a Harmful Chemcial
• The International Agency for
Research on Cancer (IARC) is part
of the World Health Organization
(WHO). Its major goal is to identify
causes of cancer. IARC has
concluded that formaldehyde is
"carcinogenic to humans" based
on higher risks of nasopharyngeal
cancer and leukemia.The
Environmental Protection Agency
(EPA) mainta The EPA has
classified formaldehyde as a
"probable human carcinogen."

Formaldehyde a work place
Carcinogen
• In the interim NIOSH
recommends that, as a
prudent public health
measure, engineering
controls and stringent work
practices be employed to
reduce occupational
exposure to the lowest
feasible limit.

Great question why we
still use Formaldehyde
??????????

Need for Newer Chemical Agents in Hospital Use
•1. A need for Non
Aldehyde based
Chemicals is growing
concern
•2 Need for quicker
sterilization methods with
ever increasing work
loads.
•3. Need for non toxic safe
agents. Dr.T.V.Rao MD @ Streilization for futture needs 27
8/15/2021

Several Chemicals are available
but the Economic Limitation are
great hurdle in exploring the Utility
in Developing countries
8/15/2021

Bacillocid® rasant
• Formaldehyde-free disinfectant
cleaner with low use
concentration
• very good cost/benefit ratio
• good material compatibility
• excellent cleaning properties
• virtually no residue
8/15/2021

Bacillocid® rasant
•Active ingredients: Glutaral 100 mg/g, benzyl-C12-
18-alkyldimethylammonium chlorides 60 mg/g,
didecyl-dimethylammonium chloride 60 mg/g.
•Bacillocid® rasant is suitable for the disinfectant
cleaning of washable surfaces using the wet-wipe-
procedure.
•Especially suitable for economic short-term
disinfection in risk areas that are likely sources of
infection Dr.T.V.Rao MD @ Streilization for futture needs 30
8/15/2021

Newer and Non Toxic
compounds.
• A Chemical compound VIRKON gaining importance as non
Aldehyde compound.
• Virkon proved to be safe
Virucidal
Bactericidal,
Fungicidal
Mycobactericidal
8/15/2021

VIKRON is Finding Place in
• As a Chemical disinfectant.
• Disinfects Medical devices.
• Disinfects Laboratory
equipment.
• Decontaminate spillages
with Blood and body fluids.
• Finding usefulness in
replacing autoclaving and
saving time.
8/15/2021

Vapour Sterilization
•Intended for condensing vapor systems (gas and
liquid phases present simultaneously)Hydrogen
Peroxide Peracetic Acid
•The presence of multiple phases simultaneously
complicates concentration determination at thepoint
of sterilization.
•Approaches for validation are a hybrid of the
liquidand gas sterilization methods.

Radiation Sterilization
• “The prevalent radiation usage is either gammarays or
electron beams. Other methods utilize xrays, microwaves
and visible light. The impact of radiation on materials can
be substantial and is amajor consideration in the selection
of radiationas a processing method.”
• “Radiation sterilization is unique in that the basisof control
… is the absorbed radiation dose, whiccan be precisely
measured. Dose setting anddose substantiation procedures
are used to validate the radiation dose required to
achievesterility assurance level.”

ENDOSCOPES

Dealing with heat sensitive
Endoscopes
•To prevent the spread of health-care–associated
infections, all heat-sensitive endoscopes (e.g.,
gastrointestinal endoscopes, bronchoscopes,
nasopharygoscopes) must be properly cleanedand,
at a minimum, subjected to high-level disinfection
after each use. High-leve disinfection can be
expected to destroy allmicroorganisms, although
when high numbers ofbacterial spores are present, a
few spores mightsurvive.

Why sterilizing Endoscopes
•Endoscopes are
routinely exposed to
mucus and other
gastrointestinal
secretions, blood,saliva,
faeces, bile,and
sometimes pus.The
process of
decontamination
comprises two basic

Ethylene oxide sterilization
• (Ethylene oxide) sterilization:
This is an alkylating agent
which reacts with DNA and
destroys the ability of
microorganisms to metabolize
or reproduce. This was a
method of choice for many
heat- and moisture-sensitive
devices but new methods of
low temparature sterilisation
are now often used as
substitutes.

Effectiveness on Ethylene oxide
• .Effective EO sterilization depends
on concentration of sterilant,
relative humidity, temperature
and exposure time. For ETO
sterilisation after loading the
steriliser, air is removed with
vacuum followed by heating upto
45-55°c with relative humidity of
60%. Required exposure to ETO is
upto 12 hours if 5psi and 6 hrs if
10 psi subsequently gas removal
by vacuum and flushing with air 4
times.

Plasma sterilisation
Plasma sterilisation: Plasma is
defined as highly ionised gas
composed of ions, electrons, and
neutral particles. Plasmas are
generated by introducing a
precursor gas or vapor (e.g.,
hydrogen peroxide or peracetic
acid) into a chamber under low-
vacuum conditions and then
exciting the gas or vapour with
microwave or radiofrequency
energy.

Why Plasma sterilization?
• The process is usually at room
temperature and hence poses no
dangers associated with high
temperatures (unlike autoclaves)
• Doesn’t involve any chemicals
and hence is non-toxic (unlike
EtOH)
• Time of treatment is fast and of
the order of 1 min or less. Is
versatile and can sterilize almost
any material and any shape

Gas Plasma
•Low-Temperature Hydrogen Peroxide Gas
•Plasma (LTHPGP)
• Gas Plasma (vaporized hydrogen peroxide) is a
relatively new option that can provide low heat
sterility cycles with none of the off-gassing concerns
present with EtO.
•• Gas plasma sterilization technology based of
Plasma was patented in 1987, and marketed in US
1993

Plasma sterilisation
• The cycle time is
approximately 75 minutes.
They have special packaging
needs as Cellulose-
containing wrappers are
incompatible with hydrogen
peroxide processes because
they absorb the peroxide
and do not allow effective
penetration.

Disadvantages of Plasma
Sterilization
• Weak penetrating power of the
plasma. Complications arise in:
Presence of organic residue
• Packaging material
• Complex geometries
• Bulk sterilization of many
devices
• • Solutions: Introduce
preferentially targeting UV/VUV
radiation of proper wavelength

SURGICAL SITE INFECTIONS
Dr.T.V.Rao MD
Dr.T.V.Rao MD 45

Varied definitions of SSI
•It is an infection occurring at the site of
surgery within 30 days of an operation
or within 1 year of an operation if a
foreign body ( i.e. an artificial heart
valve or joint ) is implanted as part of
the surgery

Surgical Site Infection
CDC defines
•A surgical site infection is an infection that
occurs after surgery in the part of the body
where the surgery took place. Surgical site
infections can sometimes be superficial
infections involving the skin only. Other surgical
site infections are more serious and can involve
tissues under the skin, organs, or implanted
material.
Dr.T.V.Rao MD 47

Surgical Site Infections
• The source of SSIs may be
endogenous (normal flora of the
patient’s skin, mucous membranes,
or hollow viscera) or exogenous,
which includes surgical personnel
(especially members of the surgical
team), the operating room
environment (including air), and
tools, instruments, and materials
brought to the sterile field during
an operation.

SSIs: Magnitude of the Problem
in USA
SSIs occur in 2.6% of all surgeries =
1.5 million SSIs annually
•SSIs are the second most common HAI
•LOS in hospital increases by 7.5 days
•Attributable cost: $25,546 (range $1783 to $134,602)
•U.S. National Cost: $130-$845 million/year
Dr.T.V.Rao MD 49

Selected Surgical Procedures Increases the Risk
• Cardiac
• Coronary Artery Bypass Graft
(CABG)
• Colon
• Hip & Knee Arthroplasty
• Abdominal & Vaginal
Hysterectomy
• Vascular Surgery:
• Aneurysm repair
• Thromboendarterectomy
• Vein Bypass Dr.T.V.Rao MD

Further Classification
•Etiology
a) Primary
The wound is the primary
site of infection
b)Secondary
Infection arises following a
complication that is not
directly related to wound
Dr.T.V.Rao MD 51

Microbiology
Nature of the Isolates
A major study
Dr.T.V.Rao MD 52

BIOSAFETY IN SURGICAL
DRESSING ROOMS
How to care for an incision, and dressing

Preparing oneself to do Dressing with safety
• Wash your hands and put on an
apron.
• Clean the trolley using soap and
water, or disinfectant, and a cloth.
Start at the top of the trolley and
work down to the bottom legs of
the trolley using single strokes
with your damp cloth.
• Place the sterile
dressing/procedure pack on the
top of the trolley.

Change the Surgical Bandage
• Before changing Dressing
you must wash your hands.
Why? Now that you have
your dirty bandage off, it is
important to clean your
hands again before touching
your incision. The bandage
and your hands will both have
bacteria on them at this point
so washing again is essential.

Cleaning the Incision
•Use soap and water to
gently clean the incision,
you do not have to use
antibacterial soap. Do
not scrub the incision,
remove scabs, or
attempt to clean the
sutures or staples.

Changing a regular dressing over
incision
•Wash your
hands before
starting the
dressing
change.

Major principles for wound
dressing
• Use Standard Precautions at all
times.
• When using a swab or gauze to
cleanse a wound, work from the
clean area out toward the
dirtier area. (Example: When
cleaning a surgical incision, start
over the incision line, and swab
downward from top to bottom).
Change the swab and proceed
again on either side of the
incision, using a new swab each

Work with aseptic methods to
change the dressings
•Open the sterile dressing
pack on top of the
trolley. Open the sterile
field using the corners of
the paper.
•Open any other sterile
items needed onto the
sterile field without
touching them.

Follow your surgeon's directions for sutures or staples,
Steri-Strips® or special dressings. If you had:
• Sutures or staples: they
will be removed at your
follow-up appointment
• Steri-Strips (thin paper-like
strips over the incision):
they will begin to fall off as
the incision heals. They do
not need to be replaced.

Prepare yourself next action to
replace the Old dressing
• Keep the new dressing
inside the sterile package
until you are ready to put it
over your incision.
• Touch only the edges of the
new dressing. Do not touch
any part of the dressing
that will be on the incision.
• Tape all sides of the
dressing securely.

Cleaning and Irrigating the Surgical
Wounds
• When irrigating a wound,
warm the solution to room
temperature, preferably to
body temperature, to
prevent lowering of the
tissue temperature. Be sure
to allow the irritant to flow
from the cleanest area to
the contaminated area to
avoid spreading pathogens.

Disposing the Old Dressing
•Remove the old
dressing by only
touching the
edges. Throw
away the old
dressing in the
garbage.

Monitoring the Wound
• Report any unusual changes
in your wound. Call your
doctor if you see signs of
infection, or if any strange
things occur around the
wound.
• Again, if you have a bad
smelling odour coming from
your wound, pus coming out
of the wound, or excessive
amounts of pain, call your
doctor.

Surgical Wound Monitoring from Home
Recent Advances with Technology
•A smartphone app called
Wound Care is
successfully enabling
patients to remotely
send images of their
surgical wounds for
monitoring by nurses.

Surgical Wound Monitoring from Home
Recent Advances with Technology
•The app was developed by researchers from the
Wisconsin Institute of Surgical Outcomes
Research (WiSOR), Department of Surgery,
University of Wisconsin, Madison, with the goal
of earlier detection of surgical site infections
and prevention of hospital readmissions. The
study results appeared on the website of the
Journal of the American College of Surgeons.

Teach Dressing management to
patients
•Provide the patient with
some dressing
management education
and answer any
questions before you
go.
•Report any changes to a
senior nurse or doctor.

NEWER STREILIZATION
METHODS

New disinfection methods
• New disinfection methods include
a persistent antimicrobial coating
that can be applied to inanimate
and animate objects (Surfacine), a
high-level disinfectant with
reduced exposure time (ortho-
phthalaldehyde), and an
antimicrobial agent that can be
applied to animate and inanimate
objects (superoxidized water)..

Antimicrobial-coated
catheters
• Antimicrobial-coated catheters
have been proposed as a
method to prevent CAUTI and
are in use worldwide, although
their clinical efficacy is not well
known. Randomized and quasi-
randomized clinical trials have
demonstrated that
antimicrobial-coated catheters
do decrease the incidence of
CABF;

Modular Operation Theatre
• Modular Operation Theatre is
the new trend of Operation
theatres where cleanliness and
sterile conditions are to be
maintained at all times. We
achieve the sterilization
conditions by using Modular
prefabricated panels,
Antibacterial flooring’s, Laminar
Flow Units, HEPA Filters and Air
Handling Units.

Modular Operation Theaters
operating department for which
the most integrated function is
required, cleanliness must be
kept and the safety of facilities,
equipment's and devices must be
maintained any times.
Furthermore, the working
environment for medical staff
such as doctors and nurses must
be considered from the view
point of human engineering.

Structural contents of Modular
Operation Theaters
• The modular operating
theatre satisfying those
conditions consists of
wall, ceiling, and is
capable of
incorporating not only
electrical equipment,
medical gas system and
lighting gears but all the
necessary functions
and equipment's at need

Modular Operations theaters
are Highly Functional
• In addition, the modular
theatre has a high availability of
extension providing for the
introduction of new facility in
the future, establishing as well
an operating environment with
high work ability and enough
function. The most complex and
challenging area of hospital
construction is the operating
department

What is Wrong in using Chemicals
“We often see cleaning staff apply a
disinfectant and then immediately
wipe it down without letting it stay
wet for the required dwell
time,”“This misstep is often
attributed to the pressures of
cleaning and the need to quickly
turn over a room for the next
patient. However, there are
products on the market that
increase cleaning efficiency while
offering a decreased dwell time.”

ARE WE MISUING
CHEMICALS???

Changing Attitude
•Because of the Covid 19 scare and other more recent
biological threats, hospitals are taking a closer look
at their disinfectant products and cleaning processes.
Health care facilities need to implement infection
control strategies that can address a wide range of
threats, including the risk posed by antibiotic-
resistant organisms such as Candida auris, an
emerging multidrug-resistant, yeast-causing invasive
HAI with high mortality.

What infections need More
attention
• Recently, the Centers for Disease
Control and Prevention (CDC)
revised its recommendation for C.
auris infection-control measures
to include thorough daily and
after-discharge cleaning of C. auris
patient rooms using
Environmental Protection Agency
(EPA)-registered hospital
disinfectants that are effective
against Clostridium difficile.

Ultraviolet Light is only Supplant
and not a substitute
• Growth of ultraviolet (UV)
disinfecting technologies has
had a minimal effect on
manufacturers of cleaning
chemicals. In fact, the two
product categories are
complementary.. It’s important
to remember, though, that they
are designed to supplement,
not replace, manual surface
cleaning and disinfection with
EPA-registered disinfectants.

Chemical Methods of
Microbial Control
• Enzymes
• Antimicrobial enzymes act against microorganisms
• Human tears contain lysozyme
• Digests peptidoglycan cell wall of bacteria
• Enzymes to control microbes in the environment
• Lysozyme used to reduce the number of bacteria in cheese
• Prionzyme can remove prions on medical instruments

Looking ahead Search is on for
future
• In recent years, we’ve seen
new cleaning chemicals
with short contact times
against a broad spectrum of
organisms, including spores.
We expect this trend to
continue, with contact
times getting shorter and
the breadth of efficiency
increasing,”

New Chemicals for floor cleaning
• National Institute for Occupational Health (NIOSH), received a
request to conduct a health hazard evaluation at a Pennsylvania
hospital using a new surface cleaning product consisting of
hydrogen peroxide (HP), peroxyacetic acid (PAA), and acetic
acid (AA). The request cited concerns about exposure of
hospital environmental services staff to the cleaning product
and reported symptoms including burning eyes, nose, and
throat; cough; headache; asthma exacerbations; and skin burns.
A summary of the NIOSH evaluation was recently published in
the Centers for Disease Control and

India released the fourth draft Chemicals
(Management and Safety) Rules
• India released the fourth draft Chemicals (Management and Safety)
Rules to select groups on March 16, 2020. This fourth draft is believed
to be the final draft, despite assurances in February that the third
draft was the final draft. The government is accepting comments until
March 31, 2020. The draft Rules include significant revisions to the list
of priority substances that are subject to importation notifications,
and hazard communication obligations (i.e., safety data sheets,
labeling, and packaging). In addition, the draft Rules include 37
substances that are subject to registration.

Life at Risk - keep the casualt update and
safe
Dr.T.V.Rao MD 85

Causality is the face of any hospital
• Causality services if well established will bring in confidence in the
patients and by standards.
• A causality is the index of services of any other area in the Hospital in
human safety,
However a good organizational practices will bring in creditability for all
our efforts.
• A causality is the index of the Hospital emergency services provided to
the Society and Public at Large. All groups are receive round the clock .
Dr.T.V.Rao MD 86

• We have to practice more
dedicated hygienic practice in
paediatrics facilities where
patients with stool and urine
incontinence are encountered
more frequently. Also increased
frequency of cleaning may be
needed in a Protective
Environment to minimize dust
accumulation
Better cleaning in dealing with patients
admitted with diarrheal diseases
Dr.T.V.Rao MD 87

What disinfects used for cleaning
•The disinfectants or detergents/disinfectants that
best meet the overall needs of the healthcare
facility for routine cleaning and disinfection should
be selected . In general, use of the existing facility
detergent/disinfectant according to the
manufacturer’s recommendations for amount,
dilution, and contact time is sufficient to remove
pathogens from surfaces of rooms where colonized
or infected individuals were housed.
Dr.T.V.Rao MD 88

• No additional precautions are
needed for non-medical solid
waste that is being removed
from rooms of patients on
Transmission-Based
Precautions. Solid waste may
be contained in a single bag
(as compared to using two
bags) of sufficient strength
Solid waste
Dr.T.V.Rao MD 89

Our clean hands save many patients do not
forget to wash hands
Dr.T.V.Rao MD 90

References
• Current Sterilization methods CDC
• NIH
• WHO Safe practices in health care
• PubMed resources

STERILIZATION PRACTICES FROM PAST TO FUTURE NEEDS by T.V.Rao MD

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STERILIZATION PRACTICES FROM PAST TO FUTURE NEEDS by T.V.Rao MD