DEFINITIONS Aseptic technique: prevention of microbial
contamination of tissues & sterile materials by excluding, removing or killing microorganisms
Disinfection: killing or removal of sufficient microbes to render an inanimate object safe for its intended purpose
Antiseptics: Chemicals which can be applied to living tissues to kill or inhibit the growth of microbes
CHOICE OF ANTISEPTIC
Ideal antiseptic:
a. spectrum of activity broad
b. resistant to inactivation by organic materialsblood & feces
c. no toxicity or allergic reaction, non –staining
d. inexpensive
Preventative Measures-patient
Short hospital stay preoperatively Shower a day before surgery Treatment of any infectious site before surgery Aseptic methods Special preparations - bowel preparation for
colonic surgery use of antiseptic solution Prophylactic antibiotics
Operating Theater
Staff Wear clean clothes, shoes or covers,
mask & cap Scrubbing for at least 5 min dry with sterile towel & apply 70%
alcohol Put on sterile gloves & gowns
Patient
Clean the operation field with antiseptic
- Chlorohexidine & 2.5% Iodine for adults
- 70% alcohol for children- Povidone Iodine for all ages if available cover with sterile drapes
Operating Room
number of personnel reducedadequate ventilationwindows should be open to allow ingress of
fresh outside air & escape of anesthetic gases
Keep all doors closed except as needed for passage of equipment & personnel
Clean operating rooms between operations
Instruments
Sterilization: - is a process by which inanimate objects are made free of all microorganisms
Sterilize:Chemical
High-pressure steamDry heat
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Decontaminate
Clean
Dry/Cool and Store
High-Level Disinfect:
BoilSteamChemical
Aseptic Instrument ProcessingAseptic Instrument Processing
Instrument Processing
Effectiveness of Methods for Processing Instruments
Method Effectiveness(kill or remove
microorganisms)
End Point
Decontamination Kills HBV and HIV and most microorganisms
10-minute soak
Cleaning (water only) Up to 50% Until visibly clean
Cleaning (water and soap)
Up to 80% Until visibly clean
Sterilization 100% High-pressure steam, dry heat, or chemical
High-Level Disinfection
95% (does not inactivate some endospores)
Boiling, steaming, or chemical for 20 min
Autoclaving
preferred method uses steam at a pressure of 750 mmHg
above atmospheric pressure & temperature of 120 degree Celcius for 15-30 mins
steam is helpful for penetration even into spores
Appropriate indicators needed
Dry heat
poor alternativesuitable for metal instrumentsuses a temperature of 170 degree
celcius for 2 hrs
Alcohols
ethyl, isopropyl Acts by denaturing proteins Broad spectrum-gram-positive & gram-negative rapid action short acting moderately expensive most active against bacteria at 70%
concentration Is bactericidal Also fungicidal & virucidal
Chlorhexidine
Good activity against staphylococci & streptococci
moderate activity against gram negative bacteria
persistent action-up to 6 hrsmoderately expensivenon-toxicunpleasant taste