Aseptic surgical technique Flashcards
What is meant by the term disinfectant?
an agent that is lethal to vegetative organisms
What is meant by the term antiseptic?
an agent that is lethal to vegetative organisms but is suitable for use within living tissue
What is meant by the term bacteristatic?
agent that inhibits or arrests the growth of bacteria
What is meant by a bactericidal?
an agent that kills bacteria
What is cleansing?
removal of visible contaminant from surfaces - it often employs the use of a detergent
What is a detergent?
a cleansing agent that acts upon surfaces
What is the meaning of sterile?
free from micro-organisms and only possible to attain on inanimate surfaces
What is meant by the term sterilisation?
free from microorganisms - absolute term and only possible on inanimate objects
Are spores more resistant to a dry heat or a wet heat?
Spores are more resistant to a dry heat than a wet heat
Is boiling water an effective means of sterilisation?
It is considered to be a form of disinfectant rather than a method of sterilisation.
Steam under pressure is able to sterilise, why is this?
Boiling water will not sterilise due to its relatively low temperature -saturated steam under pressure is able to produce the greater temperatures that are required for sterilisation
Briefly describe the temperature and time in the autoclave for routine instrument sterilisation, emergency (flash) and linen packs:
Routine instrument - 15 min @ 121 degrees
Emergency flash - 3 min @ 134 degrees
Linen packs - 30 min @ 121 degrees
How does dry heat kills organisms?
Kills organisms by oxidation and removal of water
What is a disadvantage of using dry heat?
Temperature and time required are significantly higher and longer than those required for moist heat sterilisation
When would radiation be useful as a technique for sterilisation?
Useful for heat sensitive pharmaceuticals, heat sensitive surgical materials (graft implants) and plastic wrapped disposable items (syringes, catheters)
Briefly describe the activity of alcohols:
Bactericidal, rapid and immediate effect bu no residual. They are very effective against bacteria but poor against spores, fungi and viruses
The effect of alcohols on organic material:
They are affected by the presence of proteinaceous material
Provide some potential uses for alcohols:
Suitable for skin defatting and preliminary disinfection (rapidly bactericidal)
Briefly describe the activity of the Iodophors:
They are rapidly bactericidal in their actions and have residual activity of about an hour. They are fungicidal and virucidal at high concentration but not sporicidal
Does organic matter impact upon the effectiveness of iodophors?
yes the activity of them is reduced by the presence of organic matter
What are some potential uses for iodophors?
Iodine scrub/solution is effective as a skin disinfectant. Dilute solutions 0.01-1% (higher concentrations are cytotoxic) can be used for wound lavage
Briefly describe the activity of chlorhexidine:
Good broad spectrum bactericidal (only sporadical at 1%) and has a greater initial reduction in numbers than the iodophors.
What is the effect of increased organic matter on Chlorhexidine?
Increased organic matter reduces the effectiveness of chlorhexidine
What are some potential uses for chlorhexidine?
Surgical scrub - comes as a stock 4% detergent
Comes as a 2% stock solution in a bottle
Rank the disinfectants (alcohol, chlorhexidine and povidone-iodine) in order of greatest immediate effect, activity reduced by organic matter and residual activity:
Greatest immediate effect: alcohol > chlorhexidine > povidone-iodine
Activity reduced by organic matter: alcohol > povidone-iodine > chlorhexidine
Residual activity: Chlorhexidine > povidone-iodine > alcohol
