Hospital Sterilization Protocols

Basics & Spaulding - Sterile Start

• Sterilization: Process destroying/eliminating ALL forms of microbial life, including bacterial spores.
• Disinfection: Process eliminating many or all pathogenic microorganisms, except bacterial spores, on inanimate objects.
• Antisepsis: Application of an antimicrobial chemical to living tissue/skin to reduce the number of microbes.
• Asepsis: Practices/procedures to prevent contamination from pathogens.

Spaulding Classification Table:

Sterilization Methods - Germ Annihilators

Physical Methods:

• Heat: Most reliable; denatures proteins.

  Method	Temp/Time/Pressure	Key Uses
  Hot Air Oven	160°C, 2h / 170°C, 1h	Glassware, oils, powders
  Autoclave	121°C, 15psi, 15-20m / 134°C, 3-5m 📌121/15/15	Surgical inst., media
  Boiling	100°C, 10-30m	Kills vegetative, not spores
  Pasteurization	LTH 63°C, 30m; HTST 72°C, 15s	Milk, vaccines

  • Incineration (waste destruction), Flaming (loops).
• Radiation:
  • UV (Non-ionizing): Surfaces, air. Low penetration.
  • Gamma/X-rays (Ionizing): Catheters, gloves. Cold sterilization.
• Filtration: Heat-labile fluids (sera, antibiotics), air (HEPA filters).

Chemical Methods:

• Gases:
  • Ethylene Oxide (ETO): Heat-sensitive items. 30-60°C, 40-60% RH, 4-18h. Toxic.
  • H₂O₂ Plasma: Low temp, non-toxic byproducts.
• Liquids (Sterilants/High-Level Disinfectants):
  • Glutaraldehyde (2%), Peracetic acid.

⭐ Autoclaving (saturated steam at 121°C for 15-20 min or 134°C for 3-5 min) is the most reliable method for sterilizing most heat-stable surgical instruments.

Disinfection Deep Dive - Bug Busters

• Levels: High (kills all, many spores), Intermediate (kills TB, viruses, fungi), Low (kills most bacteria, some viruses/fungi).

Hospital Protocols & Monitoring - Guardian Systems

• Central Sterile Supply Department (CSSD): Hub for sterile instrument processing.

• Instrument Processing (Spaulding's Classification):
  • Critical (e.g., surgical tools): Sterilization.
  • Semi-critical (e.g., endoscopes): High-Level Disinfection (HLD) / Sterilization.
  • Non-critical (e.g., BP cuff): Cleaning/Low-Level Disinfection.
• Sterilization Monitoring:
  • Physical: Cycle charts (temperature, pressure, time).
  • Chemical:
    • Process Indicators (e.g., autoclave tape).
    • Specific tests (e.g., Bowie-Dick test for prevacuum autoclaves - checks air removal).
    • Integrating Indicators (Class 5 - react to all critical parameters).
  • Biological (BIs): Spore tests - definitive proof.
    • Geobacillus stearothermophilus: Steam (121°C, 134°C), H₂O₂ plasma.
    • Bacillus atrophaeus: Ethylene Oxide (ETO), Dry Heat (160°C).
    • 📌 Mnemonic: Steam → Stearothermophilus; ETO/Dry Heat → Atrophaeus.

⭐ Biological indicators (BIs) using spores (e.g., Geobacillus stearothermophilus for steam/H₂O₂ plasma; Bacillus atrophaeus for ETO/dry heat) are the gold standard for verifying sterilization efficacy.

• Biomedical Waste (BMW) Management: Strict segregation (color-coded bags) & appropriate treatment (autoclave, incineration, etc.).

High‑Yield Points - ⚡ Biggest Takeaways

• Autoclaving (121°C, 15 psi, 15-20 min) is key for most surgical instruments and media.
• Dry heat (160°C, 2 hrs) for powders, oils, glassware.
• Ethylene Oxide (ETO): cold sterilization for heat-sensitive items; requires aeration.
• 2% Glutaraldehyde: chemical sterilant with long immersion (6-10 hrs).
• Plasma sterilization (H₂O₂): rapid, low-temp method for delicate instruments.
• Biological indicators (e.g., G. stearothermophilus for autoclave) ensure sterility assurance.
• CSSD centralizes and standardizes hospital sterilization protocols.