5.4 Infection control procedures of anesthesia equipment 

If proper procedures are not followed, it is possible for contaminated anesthesia equipment to transmit infection to patients. Since it is impossible to know which equipment has become contaminated, all used equipment should be considered contaminated and appropriate infection control precautions should be taken in handling used equipment. 

5.4.1 Spaulding classification: 

A strategy developed by Dr. Earle H. Spaulding for reprocessing contaminated medical devices. The system classifies devices as critical, semicritical, or noncritical based on the risk from contamination of a device to a patient. Three different levels of disinfection are applied based on this risk scheme. For example a needle used for entry into tissue is critical and needs to be sterile. A speculum (endoscopes) has contact with mucous membranes and therefore needs to be cleaned and then undergo high-level disinfection. A blood pressure cuff has contact with intact skin and only needs cleaning. 

5.4.2 Equipment requiring sterility: 

Equipment that will enter or contact anybody area that is normally sterile must be sterile at the time of use, and aseptic techniques must be employed to maintain sterility. 

• This equipment would include vascular needles and catheters; regional block needles and catheters; the interior of associated tubing, connectors and syringes; and urinary catheters (Spaulding's "Critical" items). 
• Reusable equipment must be thoroughly cleaned and subjected to a sterilization process prior to reuse. 
• Sterility must be assured at the time of use. If an item's sterility is in doubt, it should not be used. 
• To avoid introduction of pathogens into sterile areas, aseptic techniques should be followed in handling and using sterile equipment. 

5.4.3 Equipment requiring high-level disinfection:

Equipment that will contact mucous membranes but would not ordinarily penetrate body surfaces should be free from contamination but need not be sterile. 

• This equipment would include laryngoscope blades, oral and nasal airways, face masks, breathing circuits and connectors, self-inflating resuscitation bags, esophageal stethoscopes and esophageal/nasopharyngeal/rectal temperature probes (Spaulding’s "Semi-critical" items). Laryngoscope blade shall be processed separately after decontamination10 minutes of high level disinfection is sufficient otherwise the gasket which hold the bulb and the bulb itself will be destroyed 
• Condensate that collects in the tubing of breathing circuits should periodically be drained away from the patient's airway and discarded. 
• Endotracheal and endobronchial tubes should be kept free from contamination until the time of use, although it is expected that some contamination from oral/nasal secretions is likely during placement of these tubes. Other contamination should be avoided carefully. 
• Lubricants, stylets and suction catheters for use with these tubes should also be free from contamination. 
• Reusable items should be rinsed to remove blood and secretions as soon as possible after use. Reusable items must be decontaminated prior to reuse by thorough cleaning, followed by either a sterilization process or high-level disinfection. 
• Routine sterilization/disinfection of the internal components of the anesthesia machine (e.g., gas outlets, gas valves, pressure regulators, flow meters and vaporizers) is not necessary or reasonably feasible. Unidirectional valves and carbon dioxide absorber chambers should be cleaned and disinfected periodically. The manufacturer's recommendations should be followed in cleaning and disinfecting anesthesia machines. 
• Anesthesia ventilator tubing and bellows should be cleaned and disinfected at regular intervals. In contrast to respiratory therapy equipment, anesthesia ventilators are thought to represent a low risk for infection transmission and need not undergo cleaning and disinfection following each use. 
• Lensed equipment, including flexible fiberoptic endoscopes, requires special processing to avoid damaging the instrument during cleaning and disinfection/sterilization. 
• Manufacturer's instructions should be followed for cleaning and disinfecting/sterilizing these instruments. Since suction and other working channels of flexible endoscopes may become contaminated with organic material during use, it is important that the lumens be rinsed as soon as possible after use and thoroughly cleaned of organic debris before disinfection/sterilization. Endoscopes that contact only mucous membranes should receive at least high-level disinfection, while those that enter sterile body spaces should undergo sterilization. 

5.4.4 Equipment requiring cleaning: 

Equipment that does not ordinarily touch the patient or that touches only intact skin should be cleaned with a disinfectant at the end of the day and whenever visibly contaminated. 

• This equipment includes noninvasive blood pressure cuffs and tubing, pulse oximeter probes and cables, stethoscopes, electrocardiographic cables, skin temperature sensors, head straps, blood warmers, the exterior of the anesthesia machine, the exterior of monitoring equipment and equipment carts. 
• Horizontal surfaces (e.g., anesthesia machines and equipment carts) are more prone to contamination during use and should be cleaned after each patient. Frequently used knobs (e.g., pop-off, flow controls and vaporizers) also should be cleaned regularly.