Traceability during instrument sterilisation

Today, most surgical instruments are reusable, and retrieving these devices has become a speciality practice that is typically centralised within an in-house sterilisation service and supervised by a pharmacist or suitably qualified person. The critical sterilisation cycle is made up of several steps: pre-disinfection; cleaning; reprocessing, and sterilisation. This cycle is reinitiated after each use. As a consequence, traceability is paramount.

French legislation requires medical equipment traceability. That is, the last five patients having been in contact with a medical instrument must be identifiable. However, the methods deployed to achieve this are not specified. Thus, some hospitals may decide not to track every individual instrument, but perhaps just each instrument batch.

It is up to each establishment to source the most appropriate identification technology. Requiring simple, practical and foolproof instrument identification, the Centre Hospitalier Privé de la Loire (CHPL) Hospital in St Etienne opted for Technifor’s Global solution. Based on micro-percussion technology, Global is designed purposely for 2D DataMatrix marking and reading in all surgical instrument identification applications.

“We looked at a number of different options before we chose micro-percussion technology,” says project head Pierre Faure, “but they were less suitable. Laser marks are prone to erosion caused by repeated sterilisation processes, for example, while adhesive Radio Frequency Identity (RFID) tags will not stand up to the high temperatures of the autoclaves.

“RFID was also an expensive option; tags cost €1 each, whereas with micro-percussion, there’s no marginal cost per instrument marked. In fact, we estimate the investment return on the Technifor marking machine will be reached once 40% of the instrument inventory is marked.”

Global consists of a micro-percussion marking machine and a universal application that can mark exceptionally small codes on even the most complex instruments (tweezers, scissors, cups, etc). A position compensator assists the machine operator in placing and bracing the instrument. For DataMatrix code re-reading, a sealed table reader is supplied with an easy-to-use interface. Its integrated lighting allows for faultless 2D-type code reading on occasions when there is little contrast. Additionally, the machine’s reading process requires no manual triggering by the operator.

Global is installed within the sterilisation department on the ground floor at CHPL (directly below the operating department that it serves). Used and soiled instruments are conveyed to the washing area by means of a small elevator, not dissimilar to a dumb-waiter found in split-level restaurants. This is the beginning of a multi-stage process that ends with the sterilised items re-packed and returned to the operating theatre ready for the next procedure.

Faure explains the process: “The soiled tools are transported to the pre-disinfection area where they are cleaned for at least 15 minutes to remove all visible debris,” he says. “The instruments are then moved to the inspection area where they’re checked for damage. Once this task is complete the 2D matrix is scanned using a Cognex handheld scanner and the tools are packed in a box, sealed sachet or tray, and sent to the next stage in the process.”

Instruments that are not already marked are intercepted at this point and taken to an adjacent room where machine operator Patrick Jeandet is responsible for engraving the 2D DataMatrix or an alphabetical text using the Technifor CN312c micro-percussion marking machine.

Indellible marking
Despite micro-percussion being an impact process, even the smallest and most delicate of surgical instruments can be marked. The fact that the mark is indelible means the instrument can undergo the sterilisation process unlimited times without any adverse effects on the mark.

CHPL commonly uses an organisational strategy that offers ‘identical’ packaging re-composition. For example, reusable medical equipment may be reprocessed: as a single unit, wrapped in a single-use wrapping; in a bath (composed of various instruments related to a given procedure); in a tray using a Pasteur folding wrapping; or as a batch in a container using a reusable wrapping.

Another fundamental reason for selecting Technifor micro-percussion technology was its suitability as an ideal solution for optimal ‘identical’ reprocessing.

During reprocessing, the unique identification code is read on every previously marked instrument. The database saves and checks this data, which guarantees perfect reprocessing of the wrappings, Pasteur-folded trays or corresponding containers. Each package with its contents is then sterilised, reused and monitored constantly throughout its usable life.

Complex wrapping
The decision to mark instruments in-house was taken after careful consideration. Outsourcing would have required repeated complex wrapping procedures and despatch. With such an important workload, the health establishment could afford neither to let its tools go, nor the extra costs associated with such a process.

“Some of our instruments must be operational within hours of arrival in the sterilisation department,” says Faure. “We didn’t want to be dependent on external resources. With the Technifor system, we are both autonomous and efficient.’’

Up to 100 patients undergo surgery at CHPL every day, which means the hospital has an extensive instrument inventory. According to Christine Chave, CHPL sterile processing department manager, approximately 20,000 tools will eventually be marked (today, 5000 instruments are already identified).

Despite the arduous conditions of the sterilisation process (134°C for 18 minutes), Technifor’s micro-percussion technology is offering reliable and effective service, as well as providing many benefits, such as the absence of corrosion, high process/cost efficiency and ease-of-use.

Micro-percussion also meets a pharmacist’s two most important criteria: hygiene and the EC medical instrument manufacturer’s warranty preservation: tools marked using micro-percussion techniques are not mechanically altered. For this reason, micro-percussion technology is also used extensively in the aerospace industry.

“We see many patients, we perform many operations and possess a great number of surgical instruments,’’ Chave explains. “However, it is our social and legal responsibility to sterilise and trace each device.

“Furthermore, this project to trace instruments has provided us with real quality management.’’

Francis Reymondon, the engineer in charge of the project’s set-up, supports these views, adding: “Tracking the sterilisation process greatly surpasses the legal requirement in France. For example, it allows production follow-up, piloting and the related analysis, such as activity logbook, simultaneous inventory and unitary instrument maintenance follow-up.’’