Hygiene

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Hygiene

• Lecture in Basic Nursing
• Thursday November 15. 2007
• Margrethe Truelsen

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Hygiene Content of lecture

• Definition
• History
• Microorganisms
• Infection
• Different ways of infection
• Requirements for infection
• Modes of transmission

• Disinfection and sterilisation
• Hand hygiene
• Isolation
• Sterile work techniques
• Vaccination
• Case Questions

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Hygiene

• Definition There are several different
  definitions of hygiene, one example isThe
  science of health, and the practice of
  cleanliness that promotes good health and
  well-being. www.dana-farber.org/can/di
  ctionary/
• The word Hygiene originates from the
  greekHygieia, which means knowledge of health,
  and in greek mythology Hygieia was the godess
  of Health.

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History

• Hygiene is closely related to washing and
  cleaning. These actions are taken in order to
  promote health and well-being.
• All through history different emphasis has been
  given to hygiene and the importance of hygiene.
• The discovery of bacterias in the 1840's and 50's
  had a great impact on the term hygiene,
  especially in health institutions. Now there was
  proof of the importance of washing, cleaning and
  disinfecting.
• So today a big part of Hygiene is about removing
  and destroying bacterias and other microorganisms.

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Microorganisms

• There are different kinds of microorganisms that
  can invade the human body and cause infections
• Bacteria microscopic, single-celled organisms.
  Examples Streptococcus pyogenes (strep throat)
  Escherichia coli (urinary tract infection).
• Virus small infectious organismmuch smaller
  than a fungus or bacteriumcannot reproduce on
  its own. Examples Varicella zoster
  (chickenpox) Rhinovirus (common cold).
• Yeast/fungi actually a type of plant. Examples
  Candida albicans (vaginal yeast infection) Tinea
  pedis (athlete's foot).
• Parasites an organism, such as a worm or
  single-celledanimal, that survives by living
  inside another, usually much largerorganism.
  Examples Enterobius vermicularis (pinworm)
  Plasmodium falciparum (malaria).

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Infection

• Microorganisms exist everywhere even many places
  in the human body on the skin, on all mucous
  membranes etc. This is called the natural flora
  of the body.
• When the human body is invaded by microorganisms,
  either from the natural flora or from outside, it
  is called an infection. If the immune system
  cannot fight the microorganisms, they may cause
  serious diseases.

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Different ways of infection

• Endogenous When the body is invaded by
  microorganisms from it's own natural flora. These
  microrganisms would normally not cause an
  infection, but if the person is very weak or the
  microorganisms become excessive, it can be
  harmful.
• Exogenous The body is invaded by microorganisms
  from outside. This happens via the skin or the
  mucous membranes.
• Cross infections Also an exogenous way of
  infection, but here the microrganisms come from
  one person and invades another person.
• Nosocomiel infection This means an
  infectionacquired while the person is admitted
  to a hospital.

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Requirements for the infection

• Three factors must be present for the infection
  to take place.1) Source of infection
  microorganisms that can originate from different
  places, like other infected persons or persons
  who are colonised, but not infected.2) Mode of
  transmission the way the microorganisms get
  transferred from one person to another. Detailed
  description of the various ways will follow.3)
  Susceptible host Any person that is exposed to
  microorganisms. In a hospital the patients are
  especially susceptible to transmission, because
  most of them are weak and have an impaired
  immunesystem.

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Modes of transmission

• Contact transmission This is the most common way
  of transmission. It involves either direct
  physical contact or indirect contact between the
  source of infection and the host.Indirect
  contact can be by touching doorknobs, water-taps
  or other contaminated sources in the hospital,
  like instruments linen etc. It can also be
  transferred via the hands of the nurses or other
  health staff.Indirect contact transmission is
  the most common mode of transmission for
  nosocomiel infections.

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Modes of transmission

• Airborne transmission Some microorganisms can
  survive for a period of time in dust-particles or
  small drops of water.The drops come from
  sneezing, coughing or even speaking from an
  infected person. Big drops fall quickly to the
  floor, and the host must be within approximately
  1 meter to get transmitted. However small
  droplets can stay and float in the air for
  several hours, so this way of transmission can
  happen over longer distances (for example same
  room, same house).Dust-particles can come from
  linen, clothes or skin and in a room with many
  people and high activity there is a high amount
  of particles.

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Modes of transmission

• Food/water transmission This happens when the
  host consumes food or drinks that are
  contaminated with microorganisms. Examples of
  infections transmitted this way Salmonella,
  Campylobacter, Hepatitis A and different
  viruses.
• Insect transmission Microorganisms are
  transferred to the host by a blood-sucking
  insect. Examples of diseases transferred this
  way Malaria, Borreliosis andYellow Fever.

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Modes of transmission

• Blood/body-fluid transmission Here
  microorganisms are transferred to the host via
  lesions in skin, tissue or mucous membranes.
  Often it happens from contaminated instruments
  like needles or knifes, but the infection can
  also come from transplantation with infected
  blood or tissue.A pregnant woman can transmit an
  infection to her unborn child via the blood in
  the umbilical cord.Examples of diseases
  transmitted this way Hepatitis B and C, HIV and
  Tetanus.

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Disinfection and sterilisation

• To prevent infections the most important step is
  to break the chain of transmission. Since there
  will always be sources of infections and
  susceptible hosts in the hospital environment, we
  can only try to prevent the mode of transmission.
  This means try to minimise the amount of
  microorganisms in the surroundings. There are
  three major approaches to do this1) Cleaning
  Removes visible dust and material. Limiting the
  amount of microorganisms.2) Disinfection
  Removes or kills normal pathogenic
  microorganisms.3) Sterilisation Removes and
  kills all microorganisms, even more resistant
  types.

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Disinfection and sterilisation

• Cleaning Is most often performed using water and
  normal soap. This physically removes dirt and
  dust andthereby limits the growth of
  microorganisms.
• Disinfection Can be performed by either moist
  heat or chemical substances. The most effective
  way is boiling (100C) for 1 min. Not all
  equipment is suited for so high temperature and
  since most microorganisms die around 60-70C, it
  is sufficient to wash in 80C water for 10
  min.Chemical disinfection is performed using for
  example alcohol (ethanol) or chlorine
  solutions.Ethanol 70-85 is used for
  disinfection of skin or disinfection of surfaces
  like tables etc.

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Disinfection and sterilisation

• Sterilisation This method is used when it is
  extremely important that no microorganisms are
  present. Utensils used for invasive techniques
  like needles, catheters etc. needs to be sterile.
  Sterile utensils is used in operations,
  injections, wound-dressing and sample
  collection.The most common way of sterilising
  utensils is by autoclaving.An autoclave is a
  chamber with high pressure and high temperature
  that ensures all microorganisms to die.
  Sterilisation can also be done by gas. Ethylene
  oxide is passed over and around utensils, which
  is hereby sterilised.It is important to know
  special techniquesto work properly in a sterile
  manner.

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Hand Hygiene

• One of the most important things to remember for
  a nurse is to ensure a good hand hygiene. If the
  nurse remembers to wash or disinfect her hands
  every time it is necessary, many infections can
  be prevented.
• When is it necessary to clean your hands ?1)
  Before performing clean or sterile procedures.2)
  Before handling food.3) After direct contact
  with a patient.4) After soiled work (for example
  touching blood, urine, stool).5) After visits to
  the toilet.6) After sneezing or coughing.7)
  After using gloves.

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Hand Hygiene

• How to wash your hands

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Isolation

• A way to prevent transmission is to use isolation
  of the patient. This is used if the patient is
  infected with a very contageous disease.
  Isolation is effective against airborne and
  contact transmission.
• When a patient is isolated he is in a room by
  himself and is not allowed to leave the room.
• The area is divided into three categories1)
  Cleaning area This is outside the isolation-room,
  where everything should be clean and safe.2)
  Cleaning-contaminated area This is the area where
  the staff put on protection before going to see
  the patient. 3) Contaminated area This is the
  area where the infected patient must be and where
  the microorganisms are.

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Isolation

• Another form of isolation is protective
  isolation. This is when a patient is extremely
  susceptible to get an infection. (for example
  immuno-suppressed patients)In this case the
  patient needs to be protected from microorganisms
  from the surroundings. Here the patient is also
  isolated in a room, but the clean area is where
  the patient is and the contaminated area is
  outside the room.
• Protection Hospitals have different regulation
  about which protective equipment the staff should
  wear during isolation.Here are some examples

Gown
Gloves
Mask
Cap
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Sterile techniques

• Sometimes it is necessary for the nurse to use
  sterile techniques for certain procedures.
  (invasive procedures like placing a catheter or
  changing a wound dressing)How to put on
  sterilegloves

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Vaccination

• Another way to prevent infections that we have
  not discussed is vaccination. It is possible to
  make a person immune to certain diseases by
  injecting a small amount of part of the
  microorganism. The immunesystem makes sure that
  this microorganism is recognised if the person is
  exposed to it again, and it will not cause a
  disease.
• Many countries have vaccination-programmes for
  the population, to avoid spreading of harmful
  diseases. Examples of diseases that can be
  prevented by vaccinations cholera, typhoid,
  tetanus, polio and many more.

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Case

• Ms Zhang is a woman, 36 years old. She is
  admitted to your ward because of gastroenteritis
  (stomach infection), she has diarrhea. Because of
  the infection she is dizzy and dehydrated. Before
  she was admitted, she fell in her home and hurt
  her leg, so now she has an ulcer on the left
  leg.You will take care of Ms Zhang today and
  your jobs are- Serve food and water to Ms
  Zhang.- Help Ms Zhang to go to the toilet.-
  Change the dressing on Ms Zhang's ulcer.- Change
  the sheets and make the bed.- Give Ms Zhang her
  medicin (oral/pills)?

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Questions

• How will you prioritise the jobs you have to do ?
  What will you do first, next and so on... ? What
  are the reasons for your choise ?
• When will you wash your hands ? Mention exactly
  when you would wash your hands during your work.
• Will you use gloves for any of the jobs ? Which
  ones and why ?
• In the case, where do we have the source of
  infection ? Where is the highest concentration of
  microorganisms ?
• Are there any other potential sources of
  infection ?
• Remember when you try to prevent the transmission
  of microorganisms, to think about who you are
  protecting ? Ms Zhang ? Yourself ? Other patients
  ?