Essay 3- Asepsis, history. An operation room structure and organisation

What is asepsis?

• Killing of microorganisms outside the operative wound using physical methods

• Fundamental to modern surgery

• Ensures sterile conditions to prevent infections

Everything in contact with the wound must be sterile

2 types of infections

• Exogenic: originates outside the body

  • Airborne

  • Contact with contaminated objects

  • Implantation

• Endogenic: originates inside the body

  • Spread via direct contact

  • Hematogenous (via blood)

  • Lymphogenous (via the lymphatic system)

disinfection vssterilization

• Sterilization: Complete destruction of all microorganisms including spores

• Disinfection: Reduces/removes microorganisms except bacterial spores; kills vegetative forms

Operating Theatre

• Sterile environment for surgery

• Personnel and patient checked for microorganisms (nose and throat swabs)

• Surgeon’s hands examined post-disinfection

• All surfaces treated with disinfectants

Structure of Operating Theatre

• Maximum comfort

• Clean, well-lit, physiological temperature

• Separate from other hospital wards

• Minimum 40 m² per operating table

• Ceiling height: 3.2–3.25 m

each operating room be equipped with?

• 1 operating table (centered)

• Ceiling and side lamps (intense, shadow-free, movable)

• Instrument tables

• Schimmelbusch drums

  • (to sterilize and store dressings materials)

• Anesthesiology module

• Central aspiration & oxygen system

• Electrocoagulation unit

• Laparoscopic instrument set

• Intraoperative ultrasonography unit

• Laser ablation unit

Types of Operating Rooms

• Aseptic

• Septic

• One-day surgery

Additional Rooms

• Sterilization room and facility

• Washing room (soft materials)

• Washing room (surgical team)

• Anesthesia room (pre-op preparation)

• Cast room

• Changing room

• Instrument storage room

Methods of Sterilization

• Dry heat: baking, flaming (for metals)

• Steam (moist heat): autoclave

  • 120°C, 1 atm, 45 mins

  • 134°C, 3 atm, 20 mins

  • Moist heat superior to dry heat

• Dry sterilization: for thermostable, non-flammable instruments (syringes, etc.)

• Ionising radiation: gamma rays (cobalt-60), for heat-sensitive items

• Electron beam

• Chemical sterilization:

  • Ethylene oxide (kills spores)

  • Used for catheters, tubes, endoscopes

  • Equipment placed dry in folio bags for 2 days

• Disadvantages: toxic, explosive, flammable and expensive