The Importance of Cleaning Surgical Instruments
Importance of cleaning Surgical Instruments
The primary purpose of cleaning surgical instruments and scopes is to remove all inorganic and organic bioburden material from the internal and external surfaces of surgical instruments, scopes, and flexible scopes. The secondary purpose of cleaning surgical instruments and scopes is to maintain and improve the “passive Layer” of surgial stainless steel. The passive layer is provided by the manufacturer of surgical stainless steel to resist (prevent) corrosion. Proper cleaning will maintain and improve this passive layer. (for more information go to: Prevent Surgical Instrument Corrosion – Importance of Cleaning Surgical Instruments) If the manual cleaning, brushing and rinsing steps are not properly carried out, protein debris can harden and lead to formation of biofilm on the biopsy channel of the endoscope. The optimal cleaning protocol will break down bioburden and clean the surface. Inadequate cleaning can thus result in material remaining on the endoscope surfaces which prevents disinfecting of surgical instruments and/or sterilizing surgical instruments fluids or gases reaching all parts of potentially contaminated surfaces. Inadequate sterilization or disinfection may in turn result in transmission of infectious organisms when the endoscope is reused. The intricate design, delicate materials and susceptibility to damage of flexible endoscopes further complicates their decontamination.
Cleaning is the Prerequisite for Disinfecting Surgical Instruments and/or Sterilizing Surgical Instruments.
The reprocessing decontamination process, whether done manually or automatically in a washer-decontaminator- disinfector, can only be effective if cleaning is adequate. Effective disinfection or sterilization: (Generic Sterilization with a Pre-Vacuum Sterilizer (HI-VAC): 270-272° F (132-134° C), 16-minute exposure time, with 4 pulses and a 30-minute dry time. Generic Sterilization with a Gravity Displacement Sterilizer: 270-272° F (132-134° C), 30-minute exposure time, with a 30-minute dry time.) Sterilization of an inadequately cleaned instrument is not possible. Cleaning is the Prerequisite for Disinfecting Surgical Instruments and/or Sterilizing Surgical Instruments.
All disinfection processes, whether done manually or done automatically in a washer-decontaminator- disinfector, can only be effective if prior cleaning is adequate. Effective disinfection or sterilization of an inadequately cleaned surgery instrument or scope is not possible. Endoscopes should be cleaned with an enzymatic detergent compatible with the endoscope immediately after use and before manual or automated disinfection. Cleaning involves the entire endoscope, including valves, working channels, connectors and all detachable parts. High level enzymatic formulations (Enzymatic Surgical Instrument Cleaners), in combination with a high level surfactant chemical complex, have been shown to be more effective in removing stains, hard water deposits, and encrusted bioburden, while being safe to use for rigid or flexible scopes.
Enzyme cleaning concentrates function more effectively at temperatures above room temperature. The optimal range begins as > 22C - 72°F with performance reaching it's peak at 58.3C - 137F. This is often referred to as the optimal temperature for the performance or activity of enzymatic action. The activity of enzymes does not stop at higher temperatures but the level of performance does begin to decrease. Enzyme cleaning concentrates enzyme-detergents and all-in-one cleaning concentrates, which include enzymes, should be used in accordance with the manufacturer's recommendations and the recommendations of the medical devices being cleaned.
The approach is the same if the presence of pathological prions (including the prions of vCJD Creutzfeld-Jakob disease) is suspected, however attention to detail is more important. It has been long known, that prions are unusually resistant to disinfection and sterilization by physical and chemical methods in common use for decontamination of infectious pathogens. It is a difficult task to gain a consensus opinion on what constitutes optimal and practical conditions for decontamination of prions. Numerous studies have been conducted, but they do not reflect the reprocessing procedures for surgery instruments in a clinical setting which are critical for iatrogenic transmission. The method of reprocessing prion contaminated surgery instruments and scopes includes (1) decontamination by NaOH or NaOCl for 30 or 60 minutes followed by GL-autoclaving at 121°C for 30 minutes, (2) cleaning and (3) routine PL-sterilizing at 134°C. It is known that some surgery instruments cannot be decontaminated by heat and moisture. Disinfectants have been widely used for this purpose although practically ineffective. The most common practice believes that the only completely safe way to prevent transmission of vCJD is to use single-use surgery instruments. Because of the pervasive distribution of these infectious proteins and the long incubation time of the disease, reprocessing of surgery instruments and scopes has been identified as a risk factor for nosocomial transmission of vCJD. Research has shown that the agent of the vCJD disease, an infectious prion protein, is extremely resistant to today’s sterilization methods; therefore, the argument, “It does not matter if instruments are 100 percent clean, as they will be sterilized,” is definitely no longer valid. Today, we understand the washing process is fully as important as the sterilization process. Today’s standard washing processes require increasingly sophisticated cleaning concentrates. Detergents, which are used in these processes, can be mild, with a neutral pH, or they may be more aggressive, with values in the alkaline range of the pH scale. A number of hospitals and surgery centers are effectively using neutral pH “combination” enzymatic-detergent cleaners for reprocessing surgery instruments and scopes. The “combination” enzyme-detergent cleaners provide optimal cleaning as well as the highest possible level of care for surgery instruments and scopes. The early prion inactivation approach, using a high concentrate of sodium hydroxide solution or sodium hypochlorite combined with long hold times, is generally lethal for medical surgical instruments and washer-decontaminators- disinfectors. Recently, researchers have been looking for less destructive methods to decontaminate surgery instruments potentially contaminated with prions. The use of “combination” enzymatic-detergent cleaners has offered the highest level of cleaning outcomes.
Ultrasonic Surgical Instrument Cleaning
Ultrasonic cleaning of reusable endoscope accessories and components may be needed to remove material from hard-to-clean areas. The same detergent used for ultrasonic cleaning can be the same as used for manual cleaning. Recommendations for detergents used for ultrasonic cleaning are as follows:
• a non-foaming detergent must used
• the labeling of the detergent should recommend the use of the product for ultrasonic cleaning
• always use enzymatic detergents for instruments soiled with bioburden (protein, fats, starch)
• use detergents with 'surfactant' cleaning agents for removing stains and hard water mineral deposits
• the treatment cleaning time recommended by the medical device and detergent manufacturers should be observed
• avoid the inhalation of enzyme-containing detergent aerosols (risk of anaphylactic reactions) by maintaining a cover over the ultrasonic cleaner when in use.
Ultrasonic Surgical Instrument Cleaning
Ultrasonic cleaners are very effective when used with hot water per manufacturer’s recommended temperature and specially formulated detergents. It is recommended that all visible debris and blood be removed from the instrument prior to ultrasonic cleaning. Sort surgical instruments by similar metals to prevent corrosion due to the contact of dissimilar metals. (electrolytic deposition - galvanic corrosion) It is not recommended to clean plated instruments in an ultrasonic cleaner since the ultrasonic vibration and the presence of other sharp instruments may crack or rupture the plating.
• ALWAYS follow ultrasonic cleaning with separate rinse treatments. Ultrasonic cleaning will fragment and loosen soil but will not necessarily remove the soil from the surface of the surgery instrument being cleaned.
For the cleaning of endoscopes, detergents with or without enzymes, and detergents containing antimicrobial substances may be used. Use of non-foaming detergents is recommended. Foaming can inhibit good fluid contact with device surfaces, and prevent a clear field of vision during the cleaning process with a risk of injury to personnel.
The detergent selected should effectively loosen organic and non-organic material so that the flushing action of the detergent fluid and subsequent rinsing water removes the unwanted material. Combination all-in-one Enzymatic Surgical Instrument Cleaner detergent complexes have been shown to be highly effective.
Detergents may contain the following substances with properties supporting the cleaning action:
surfactants which reduce surface tension thus facilitating removal of debris
activated H2O2 which effectively loosens debris at room temperature
proteases (enzyme) which break protein debris into smaller, more soluble subunits
amylase (enzyme) which catalyses the breakdown of starch
lipase (enzyme) which breaks up fat-containing debris
quaternary ammonium compounds, biguanidine, alcohols
Other active substances recommended for cleaning include:
amine compounds
glucoprotamine
peracetic acid
hydrogen peroxide
Aldehydes Contained in Surgical Instrument Cleaning Concentrates for Cleaning Surgical Instruments and Scopes
When using Surgical Instrument Cleaning products which contain Aldehydes, be aware that they denature and coagulate protein. Amine Compounds or Glucoprotamine in combination with Glutaraldehyde and Surgical Instrument Cleaning Detergents based on amine compounds or glucoprotamine in combination with glutaraldehyde for disinfecting of surgical instruments and/or sterilizing surgical instruments should not be used as chemical reactions may result in formation of colored residues. These residues can appear to be surgical instrument corrosion. The use of a high level surgical instrument cleaning surfactants ("combination") enzyme detergent surgical instrument cleaners can be used to remove surgical instruments stains, and prevent surgical instrument corrosion and pitting of surgical instruments.
John Temple
Product Development
