Page 112 - Review of Medical Microbiology and Immunology ( PDFDrive )

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mebooksfree.com mebooksfree.com mebooksfree.com TABLE 13–2 Clinical Use of Disinfection and 101 mebooksfree.com
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CHAPTER 13 Sterilization & Disinfection
TABLE 13–1 Infection Control Precautions and
Practices
Sterilization
Example of Type of
Commonly Used
Type of
Disinfectant or Method of
Important Precaution
Patient or Type of
Practice Employed
Clinical Use
Precaution
Sterilization
Infection
1. Hand hygiene
All patients
Standard
2. Respiratory hygiene
surgery
and cough etiquette
Disinfect surgical site prior to surgery
Iodophor
3. Safe injection practices Disinfect surgeon’s hands prior to Chlorhexidine
4. Proper disposal of nee-
Disinfect skin prior to venipuncture
70% ethanol
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mebooksfree.com mebooksfree.com mebooksfree.com Cleanse wounds Thimerosal, chlorhexidine, mebooksfree.com
dles and scalpels
or immunization
Standard
If exposure to blood,
Personal protective equip-
Tincture of iodine followed by
Disinfect skin prior to blood culture
secretions, or body flu-
or inserting vascular catheter
70% ethanol, or iodophor,
ment (PPE) such as
mask, face shield, gog-
ids is likely to occur
or chlorhexidine
gles, gloves, or gown
1. Wear gloves and gown
1. Stool incontinence,
Contact
hydrogen peroxide
2. Disinfect room
e.g., Clostridium dif-
Silver sulfadiazine
Cleanse burn wounds
ficile, norovirus
2. Generalized rash,
Hypochlorite (bleach, Clorox)
Cleanup of blood spill from a patient
e.g., varicella
with hepatitis B or C (disinfect area)
(chickenpox)
3. Draining wounds
heat-sensitive materials (e.g.,
glutaraldehyde
Droplet
1. Respiratory viruses,
endoscopes, respiratory therapy
e.g., influenza 1. Face mask or face Sterilize surgical instruments and Ethylene oxide or
shield for patient and
equipment)
provider
2. Bordetella pertussis
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Sterilize non–heat-sensitive materials
Autoclave
2. Disinfect room
3. Early infection with
(e.g., surgical gowns, drapes)
Neisseria meningitidis
Filtration
Sterilize intravenous solutions
1. Tuberculosis
Airborne
1. Isolation room; nega-
tive pressure room
2. Measles
3. Varicella (chickenpox)
2. Face mask or face
(when not in use)
when patient is
shield for patient and
Benzalkonium chloride (Lysol)
Disinfect floor of operating room
coughing
provider. N-95 respira-
tor, if available.
Disinfect stethoscope
70% ethanol
3. Disinfect room
Preservative in vaccines
Thimerosal
microorganisms on the surface of skin and mucous mem- fectants and modes of sterilization.
Table 13–2 describes the clinical uses of common disin-
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branes are called antiseptics.
RATE OF KILLING OF MICROORGANISMS
Death of microorganisms occurs at a certain rate depen-
still cause problems (see page 46).
dent primarily on two variables: the concentration of the
killing agent and the length of time the agent is applied.
The rate of killing is defined by the relationship
CHEMICAL AGENTS
N ∝ 1/CT
isms. A quantitative measure of this variation is expressed
which shows that the number of survivors, N, is inversely Chemicals vary greatly in their ability to kill microorgan-
as the phenol coefficient, which is the ratio of the concen-
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proportionate to the concentration of the agent, C, and to
tration of phenol to the concentration of the agent required
to cause the same amount of killing under the standard
the time of application of the agent, T. Collectively, CT is
conditions of the test.
often referred to as the dose. Stated alternatively, the num-
Chemical agents act primarily by one of the three
ber of microorganisms killed is directly proportionate to
CT. The relationship is usually stated in terms of survivors
membrane, (2) modification of proteins, or (3) modifica-
because they are easily measured by colony formation.
Death is defined as the inability to reproduce. In certain
tion of DNA. Each of the following chemical agents has
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