Flashcards in Infection Deck (14)
What are the three things required for establishment of a wound infection?
1. Sufficient dose of pathogenic microorganisms
2. A suitable microbial nutrient medium
3. Impairment of natural host defenses
What is asepsis?
Prevention of wound contamination
What is antisepsis?
Killing bacteria that are already present
What harm does surgery do?
- A surgical incision is a wound: tissue trauma
- Surgery must be performed in such a way as to minimise trauma
Can can trauma manifest into?
- Loss of function
What may infection be due to?
- Pre-existing tissue contamination
- Surgical exposure of tissues to contamination
- Relative or absolute immunodeficiency
What are some predisposing factors to surgical wound infection?
- Systemically compromised patient
- Tissue hypoxia
- Tissue trauma
- Inadequate debridement
- Prolonged tissue exposure to the environment
- Foreign material in the wound
- Haematoma ( inadequate haemostasis + dead space)
- Presence of resistant organisms in the environment
Where can the source of self infection/ cross infection come from?
- Operative area
- Operative personnel
- Post-op area
What factors influence the battle between contaminants and the host's defences?
- Patient Factors
- Surgeon Factors
- Environmental Factors
Describe what patient factors are...
Who we do it to:
- Health status
- Low body weight - can become hypothermic
- Dermatitis at site
- Propensity to lick and scratch wounds
- Lack of compliance with dressings
Describe what surgeon factors are...
How we do it
- Disruption of local blood flow
- Tissue trauma
- Blood clots act as growth medium
- Foreign material e.g. sutures
- Creation of dead space
- Wicking of bacteria by multifilament sutures
- Long anaesthetic periods
- Drying of tissues
- Thermal damage from drills etc.
Describe what environmental factors are...
Where we do it
- Theatre cleanliness
- Theatre air flow
- Theatre traffic
- Hospital and ward cleanliness
- Skin clipping
- Skin disinfection
- Instrument sterility
- Gowning and gloving
- Nosocomial infection
- Sink water sterility
When should prophylactic antibiotics be given?
- Long surgeries
- Implant surgeries
- Contaminated/ dirty surgeries