Asepsis and antisepsis, disinfectants and sterilization - Department of Surgery University of Szeged

Asepsis and antisepsis, disinfectants
          and sterilization

             Department of Surgery
              University of Szeged

History of „modern surgery”
• On September 30, 1846, Morton performed
  a painless tooth extraction after
  administering ether to a patient. Upon
  reading a favorable newspaper account of
  this event, Boston surgeon Henry Jacob
  Bigelow arranged for a now-famous
  demonstration of ether on October 16, 1846
  at the operating theater of the
  Massachusetts General Hospital. At this
  demonstration Dr. John Collins Warren
  painlessly removed a tumor from the neck of
  a Mr. Edward Gilbert Abbott. The theatre
  came to be known as the Ether Dome and
  has been preserved as a monument to this
  historic event.

Replica of the inhaler used by William T. G.
                       M Replica
      of the inhaler used by William T. G. Morton
                   in 1846 in the first
     public demonstration of surgery using ether

The first use of ether as an anaesthetic
            in 1846 by Morton

            Panel from monument in Boston
               commemorating Morton's
           demonstration of the anesthetic use
                       Of ether

History-milestones of antisepsis
• Ignaz Philipp Semmelweis(July 1, 1818 – August 13, 1865)
  (born Ignác Fülöp Semmelweis)was a Hungarian physician
  now known as an early pioneer of antiseptic procedures.
•
• Described as the "savior of mothers",Semmelweis discovered
  that the incidence of puerperal fever could be drastically cut by
  the use of hand disinfection in obstetrical clinics.

• Puerperal fever was common in mid-19th-century hospitals
  and often fatal, with mortality at 10%–35%. Semmelweis
  postulated the theory of washing with chlorinated lime
  solutions in 1847 while working in Vienna General Hospital's
  First Obstetrical Clinic, where doctors' wards had three times
  the mortality of midwives' wards.

History

1847 - Semmelweis identifies
  surgeons hands as route of
  spread of puerperal infection
  (asepis)

He discovered that the incidence of puerperal fever
 could be drastically cut by the
use of hand desinfection in obbstetrical clinics.

History
                          Louis Pasteur

French chemist and microbiologist who was one of the
  most important founders of medical microbiology.
 He is remembered for his remarkable breakthroughs
      in the causes and preventions of diseases.
His discoveries reduced mortality from puerperal fever,
and he created the first vaccines for rabies and anthrax.

His experiments supported the germ theory of disease

History-milestones
• 1865 - Lister introduces hand and
  wound antisepsis with the use of
  carbolic acid

  British surgeon and a pioneer of antiseptic surgery.
   By applying Louis Pasteur's advances in microbiology,
  he promoted the idea of sterile surgery while working
  at the Glasgow Royal Infirmary. Lister successfully
  introduced
   carbolic acid (now known as phenol) to sterilise surgical
   instruments and to clean wounds, which led to a reduction
  in post-operative infections and made surgery safer for
  patients

History-milestones
1880 - von Bergmann invents
       the autoclave

• Bergmann was the first physician to introduce
  heat sterilisation of surgical instruments, thus
  greatly reducing the number of infections in
  surgery. Thus increased the responsibility of the
  surgeon for the inflammation after procedures.
  He was a surgeon in the Austro-Prussian War
  (1866) and the Franco-Prussian War (1870–71),
  where he gained experience treating cranial
  trauma and neurological disorders

Definitions
Asepsis is procedure to reduce the risk of
 bacterial contamination

• Usually involves:
    -The use of sterile instruments
    -The use of a gloved no touch
     technique

Antisepsis is the removal of transient
 microorganisms from the skin and a
 reduction in the resident flora

The operating theatre
Although aseptic surgery has been done in a
 tent, under a tree, or on a kitchen table, it is
 safer if it is done in a room which has been
 designed to preserve the sterility of the
 surgical field, to make surgical routines
 easier, and to prevent mistakes.

The operating theatre

The most serious sources of infection in
  a theatre are bacteria from:
- The pus and extcreta left behind by
  previous patient
- The clothes, hands, skin, mounths of
  the staff
- The patient himself

Minimize the risk of infection by:
• Keeping the theatre as clean as possible, so
  that the pus and excreta of previous patients
  are removed
• Making sure that the autoclaving is done
  conscientiously
• Following the rules about the indications for
  operating, the timing of operations, wound
  closure, and careful tissue handling
• Creating and maintaining the sterile zone

The sterile zone
• Has to be created a new for each
  patient in a theatre in which the risk of
  infection has been reduced as much as
  possible
• Its creation starts when a nurse swabs
  the top of trolley with antiseptic, puts
  two sterile towels on it and lays out
  sterile gowns and gloves

The sterile zone
• The operations site joins the sterile zone as
  it is prepared with an antiseptic solution and
  draped
• Nothing which is contaminated must touch
  anything in this zone until the end of the
  operation
• If the technique of the team is poor, the
  sterile zone becomes smaller and smaller as
  he operation proceeds.

Operative team
Should be as small as possible. It consist:
• Yourself the surgeon
• Your assistant, when you need one
• The scrub nurse responsible for the
  instruments
• The circulating nurse to fletch and carrry
• The anaesthetist
• His assistant, if he has one

Two other people are important

• The theatre charge nurse responsible for
  organizing the theatre

• Theatre dresser, who is less educated, but
  unlike the nurses who come and go, has
  spent his whole career in the theatre, and so
  knows its routines and where things are

Aseptic technique

Entering the theatre:
Anyone entering the theatre must change, in
  the changing room, into clogs or sandals and
  into a suit.
Decide which operations nedd gowns, gloves
  or masks.

Aseptic technique
Scrubbing up:
Adjust the elbow taps to deliver water at a
 comfortable temperature
Wet your hands, apply a little soap or forearms
 to 5 cm above your elbows for one complete
 minute
Wash your forearms

Scrubbing up:
Then take a sterile brush and put soap on it
Scrub the lateral side of your left thumb, then
 its medial side, then the lateral and medial
 aspects of each successive finger. Scrub
 your nails, and then the back and front of
 your left hand. Do the same with your right
 hand
Then take disinfectant fluid to both hand
 (1 ml/ five times)
Scrub for 5 minutes in all

Aseptic technique: gowning

• Hold the gown away from your body, high enough
  to be wel above floor
• Allow it to drop open, put your arms into the arm
  holes while keeping your arms extended
• Then flex your elbows and abduct your arms
• Wait for circulating nurse to help you
• She will grasp the inner sides of the gown at each
  shoulder and pull them over your shoulders

Aseptic technique: gloving
• Dust your hands with powder and rub them
  together to spread it
• Be careful to touch only the inner surface
  on the gloves
• Grasp the palmar aspect of the turned down
  cuff of a glove and pull it on to your
  opposite hand
• Leave its cuff for the moment

Aseptic technique: gloving

• Put the fingers of your already gloved hand
  under the inverted cuff of the other glove,
  and pull it on to your bare hand
• It is a good routine to wash your gloved
  hands sterile water to remove powder
• Now help the next person who has gowned
  on with their gloves

The operation site: shaving
• The operation site should be socially clean before the
  operation, and you may have to check this
• There is usually no need to shave a patient
• If you shave him, do so on the morning of the operation, or
  as part of the operation
• If you shave him a day or two before , minute abrasions in
  his skin will become infected and the risk of wound
  infection will increase
• If hair is going to get in the way, all you need to do is to clip
  it short immediately before the operation

The operation site: preparation
• Do this as soon as the patient is
  anaesthetized
• Start with a soapy solution, and follow this
  with spirit, or better if there is a low
  sensitivity to iodine in the community, use
  alcoholic iodine
• Take a sterile swab on a holder, start in the
  middle of the opertion site, and work
  outwards
• Discard both swab and holder, and repeat
  the proces with the second swab

The operation site: preparation
• Some surgeon consider the over-
  elaborate, and merely use a single
  application of iodine
• Be sure to prepare a wide enough area
  of skin
• In an abdominal, operation this should
  extend from the patient´s nipple line to
  below his groin

The operation site: draping
• Wait until he is anaesthetized
• Place the first towel across the lowe end of
  the operation site
• Palce another across its nearer edge
• Apply a towel clip at their intersection
• Place another towel across the opposite
  edge of the site, and finally one across its
  upper edge

The operation site: draping
• Clip them at their intersections
• If necessary, grip his skin with the clips, or secure
  the towels with a stitch
• Alternatively , drape him with two longutidunal
  towels clipped at each end, with a towel above and
  below
• Then, in an abdominal operation cover his whole
  abdomen with an abdominal sheet with a narrow
  quadrangular hole in it
• If important areas near the surgeon become
  contaminated, cover them with fresch sterile
  towels

Boiling and autoclaving
• Sterilization is the total desctruction of
  all forms of life, including bacterial
  spores
• It is best done with heat, either dry
  heat in an oven, or steam under
  pressure in an autoclave
• Processes (usually chemical) which do
  not destroy spores are termed
  „disinfection“

Boiling and autoclaving
• The basis of aseptic surgery is to kill all
  micro-organisms on all instruments and
  dressings, preferably by exposure to steam
  under pressure
• If this is impractical, imerssion in boiling
  water for 10 minutes at sea level will kill all
  viruses and all vegetative bacteria, but not
  spores, particularly those of tetanus and gas
  gangrene

Autoclaves

The sterilize is effectively, if
  there is killing all spores

Autoclaves :
simple walled autoclaves
double walled autoclaves

Sterilization
• Is the complete elimination or destruction of all
  microorganisms, including spores.
• Nurses should be familiar with agency specific
  policy and procedures for cleaning, handling and
  delivering used items for disinfection and
  sterilization.
• Most facilities have an area called Central
  Processing that performs item sterilization. This
  area is usually located next to or within the
  Surgical Department

STERILISATION METHODS

•Autoclaves

•Gas sterilisation:
             formaldehyde, ethylenoxide, H ₂ O ₂

•Radiations: Co, UV, rtg, γ

•Plasma sterilisation

Moist Heat (Autoclave)
Is the most widely used method of sterilization.
Supersaturaled moist steam under pressure which causes
   the temperature to exceed that of the boiling point of water
   can kill pathogens and spores.
250°-254°F for 30 minutes.
Items are wrapped in special cloth or paper. It is a nontoxic,
   inexpensive, sporicidal and has the ability to penetrate
   fabrics rapidly.
Autoclave method is used to sterilize surgical instruments,
   parenteral (IV) solutions and surgical dressings.

Autoclave Sterilization

• This autoclave at Raytheon was built
  especially for Starship curing. It was
  rumored to cost over $100m and is now
  being used for the Premier One fuselage

High-Speed Sterilization
          „Flash Autoclave”
• Type of moist heat – steam under
  pressure.
• Used in emergency situation – great for
  items needed quickly.
• Equipment unwrapped.
• Item placed in autoclave tray.
• Mixture of steam, pressure, & heat.

„Flash Autoclave” continued
• Heat temperature goes up to 270°F and
  timed for 3 minutes.
• Used in OR (Flash autoclave between
  each OR room).
• Used to sterilize instruments quickly.

Radiation
• Ionizing
  – used for disinfecting and sterilization
  – penetrates deeply into objects or packaging
  – used to sterile prepackaged items (dressings,
    needles, catherization trays)
  – also used to sterilize foods, drugs
  – equipment that may be damaged if exposed
    to heat (Fiberoptic Endoscopes) equipment
    very expensive

Chemical
• Chemicals are effective disinfectants because they
  attack all types of microorganisms, act rapidly, work with
  water, not inactivated by organic material, are not
  harmful to body tissues and do not harm the item being
  disinfected.
• Cold – solutions used.
• Solutions placed in sterile basin.
• Items soaked for 10-20 minutes.
• Items must be rinsed well with sterile saline or sterile
  water in second basin before using.
• Examples chemical solutions:
• Cidex – Sporocidin - Wexcide

Ethylene Oxide Gas (Autoclave)
• Is a method similar to steam autoclaving.
• Ethylene oxide gas is released into a pressurized
  chamber that gives the gas increased penetrating
  abilities.
• This gas destroys spores and pathogens by altering the
  cells metabolic process.
• Used for products that cannot be exposed to steam
  sterilization due to damage or melting due to heat from
  steam autoclave.
• Good penetrating ability, can sterilize plastic, rubber.
  (Endoscopes)
• Items are wrapped with stripped tapes that appear when
  item is sterilized.

Ethylene Oxide Gas (Autoclave)
• Ethylene Oxide (odoriess gas, which is toxic to
  humans).
• Takes 2 to 5 hours to accomplish and is more
  expensive.
• After items removed from autoclave…must not
  use for 24 hours…gas has to dissipate…larger
  hospitals have special machine to remove gas
  particles and do not have to wait 24 hours to use
  the articles.

Ethylene Oxide Gas (Autoclave)

Special indicator for gas autoclave
  Complete – color is changing

Boiling Water
• Oldest method.
• Most practical and inexpensive method for
  home use.
• Does NOT kill spores and some viruses.
• Boil 212°F for at least 15 minutes.
• Not used in hospital systems.

Antiseptics – vs - Disinfectants
• Antiseptics – Are cleaning solutions that
  inhibit and destroy microorganisms on the
  skin and wounds.
  – Example: Isopropyl alcohol, Betadine or site
    preps that contains „Surecleans”
• Disinfectants – Are cleaning solutions that
  inhibit and destroy microorganisms on
  environmental surfaces.
  – Example: Bleach solution, Wexcide

Disinfectants and antiseptics

Although heat is the best way of killing micro-
  organisms, you will have to use chemicals to
  kill them on a patient´s skin, or on anything
  which heat might harm, such as drains or
  some suture materials.

Antiseptics and disinfectants
Skin:
Any alcoholis solution will do
Alcoholic iodine is best:
Use it routinally, except in children, on the
  scrotum, and in allergic patients
0,5% chlorhexidine in spirit is a less
  satisfactory alternative
Apply it to skin after removing all traces of
  soap

Antiseptics and disinfectants
Wounds:
There is no substitude for scrubbing
 brush, plenty of water from a jug, and a
 thorough surgical toiler
Chlorhexidine is useful for cleaning the
 skin round a wound

Antiseptics and disinfectants
Instruments , suture materials and drains:
The following agent are effective against HIV and
  HBV in addition to the classical pathogens:
• 2% alkaline buffered glutaraldehyde is the best
• 5% fromalin in 70% spirit
• 0,5% solution of chlorhexidine in 70% spirit with 0,5%
  sodium nitrite
• Plain 70% spirit

Antiseptics and disinfectants

10 minutes is the absolute minimum time in
  these solutions, 24 hours is safer
Ideally nothing should be considered
  sterilized until it has been immersed for 24
  hours
Wash all equipment well before using it

Antiseptic surgery
This used to be standard practice before
  aseptic methods made it obsolete
Aim to sterilize everything coming into
  contact with the wound by soaking it for a
  sufficient time in an antiseptic solution
Antiseptic solutions: chlorhexidine 5%
Soak everything which will come into contact
  with the wound in one of these solutions
  for at least 30minutes.

Antiseptic surgery

Perioperative antibiotics:
For rutine use in antiseptic surgery
Some operators have given their patients
  antibiotics prophylactically

Antiseptic surgery
While operating:
Treat the patient´s skin with the solution for
   at least five minutes before the operation
Wash your hands as usual and put on the wet
   gloves
If you are not using gloves, soak your hands
   in solutions for five minutes