Decontamination of Surgical Instruments

Decontamination of surgical instruments is a complex process undertaken at specialist accredited decontamination facilities in the UK for hospitals.

Those specialist decontamination facilities are listed in our directory under Decontamination Facilities. To assist hospitals with their decontamination process, several consultancy companies provide Decontamination Consultants for Decontamination, Water and Ventilation.

Receiving used Surgical Instruments

Surgical instruments are complex and expensive Medical Devices used to treat patients. Once used they are returned to the decontamination facility for re-processing. Contaminated instruments should always be returned as soon as possible to ensure effective cleaning takes place, and to help prevent prions from adhering to the surgical instrument surface.

Theatre staff should always ‘pre-wet’ the tray contents before returning to ensure the contents remain moist, this will help prevent prions adhering to the surgical instrument surface. A decontamination technician will remove any outer packaging used to contain the contaminated devices. The tray is then visually checked to identify any sharps such as needles or scalpel blades. An essential part of the process now is for the decontamination technician to verify that the contents are complete, any missing surgical instrument or part of a device, must be reported immediately to the theatre team.

Figure 1 Checking Contaminated Surgical Instruments

Pre-Cleaning and special considerations taken for Decontaminating Surgical Instruments

Some surgical Instruments such as laparoscopic instruments require dismantling before, any cleaning can take place. The cannulated shafts are pre-cleaned using nylon brushes followed by irrigation using flushing nozzles, the device is submerged while this process takes place to reduce splashing and aerosol.

Figure 2 Flushing Nozzles for pre-cleaning cannulated surgical instruments

Some surgical instruments cannot be taken apart such as Da Vinci robotic instruments these require processing using a separate validated washer disinfector cycle, which includes extended pre-treatment and flushing times. Da Vinci robotic instruments also have a use-limit applied, to reduce any risk from soil build up inside the device.

Specialised cleaning racks are used to support and connect the Da Vinci robotic instruments directly to the washer disinfector, this will ensure the internal lumens are subjected to each stage of the automated wash process.

Figure 3 Da Vinci Robotic Instrument Rack

Some surgical instruments such as Kerrison rongeurs, laparoscopic needle holders and laparoscopic liver retractors can present a difficult challenge for the decontamination technician to ensure satisfactory pre-cleaning has taken place, especially removing any soiling deep from within the device. These surgical instruments are pre-cleaned using ultrasonic cleaners where the ultrasonic cavitation dislodges debris from deep crevices or blind end lumens. Failure to process this type of instrument can lead to soil build up, a common problem for non-dismantlable instruments.

Figure 4 A Kerrison Rongeur mechanically taken apart to show how debris can build up over time if the device is not properly pre-cleaned

Surgical Instrument manufacturers are now designing fully take-apart instrumentation to allow the Decontamination Technician to fully pre-clean complex devices. However, the use of ultrasonic cleaners in decontamination facilities remains paramount to the decontamination process for pre-cleaning complex surgical instruments.

Figure 5 Ultrasonic Cleaner with Surgical Instrument basket

Final stages using Washer Disinfectors

Following thorough pre-cleaning, surgical instruments are placed into a washer disinfector using an instrument wire mesh wash basket (DIN basket) or specialised instrument holding trays, again this will be wire mesh to allow draining during the wash process. It is important to ensure all surgical instruments such as forceps are in the open position and all cannulated items such as suction nozzles and orthopaedic cannulated reamers are connected to the washer disinfector via irrigation manifolds, this will ensure the internal cannulation is exposed to the decontamination chemicals.

Figure 6 Contaminated surgical instrument correctly placed on wash basket to prevent shadowing

Figure 7 Specialised wash basket for processing Phaco and Dental Handpieces using filtered flushing manifolds for connecting directly to the Washer Disinfector

A recent paper by the ‘Healthcare Safety Investigation Branch HSIB’ produced a document: “Decontamination of Surgical Instruments” highlighting the importance of correct pre-cleaning of surgical instruments with an emphasis for the decontamination technician to always follow Surgical Instruments “Manufacturer’s Instructions for Use” and in particular to ensure decontamination equipment is provided for cleaning and flushing cannulated items. Decontamination consultants can provide advice to decontamination facilities regarding all decontamination processes.

Figure 8 Surgical Instruments being Processed inside a Washer Disinfector

On average automated washer disinfectors take approximately 40 minutes to complete a wash cycle. The first stage is a cold-water rinse, followed by a detergent wash using either alkaline, enzymatic, or neutral detergents, then the load is subjected to thermal disinfection to kill any remaining pathogens (except spores and prions), following this the load is dried using filtered heated blowers. The washer disinfector is probably the most important part of the decontamination process as without this sterilisation would not be possible.

Hospital Technical Memorandum HTM 01-01 Provides guidance on decontamination of surgical instruments.