Sterilisation

• Process which kills all living microorganisms (including viruses, spores - clostridium, bacillus: rests heat, dehydration, chemical attack, ionising radiation)

Disinfection

• Process which kills most living microorganisms (except spores and viruses)

Sterilisation methods

Disinfection Methods

• Skin preparation
• Glutaraldehyde treatment of endoscopes

Determining adequacy of sterilisation

Browne's tubes		Tubes contain heat sensitive dyes
Bowie Dick tape		Stripes change to dark colour once sterilised
Lantor test

Precautions to avoid infection

1. Theatre suites
   • Theatres sited away from main hospital traffic
   • Clearly designated areas of asepsis etc
   • Positive-pressure (plenum) ventilation with 20 air changes/hour / Ultra-clean laminar airflow systems with 300 air changes/hour
2. Theatre staff
   • Minimum number of individuals necessary in theatre
   • Avoidance of excess traffic through clean areas
3. Operating personel
   • Gowns - cotton gowns reduce bacterial count by 30%
   • Caps / masks
   • Scrubbing
4. Patient
   • Minimal pre-operative stay
   • Pre-operative showering
   • Shaving only if required immediately prior to surgery
   • Skin preparation - 1% iodine or 0.5% chlorhexidine in 70% alcholol

Universal precautions

Precautions taken to protect theatre staff from infections in all patients

1. Gowns
2. Gloves
3. Masks/visors/goggles
4. No-touch technique when handling needles
5. Safe disposal of sharps