Reprocessing services offered by third-party reprocessors work as a closed cycle or loop. The used medical device is picked up at a hospital by a service-provider and, as a first step, gets registered in order to guarantee that each medical device can be returned to its original owner. After the registration with a so-called data matrix-code, which remains attached to the medical device, the medical device is cleaned. Each medical device is inspected and tested after the cleaning. Finally, the product gets sterilized and packaged and brought back to the hospital. All steps are documented during the entire process.

Pick-up at the hospital

After use, the device is placed in a special bag, and then in a designated bin. These are collected directly by the reprocessor – up to several times a week if necessary.

Registration and identification

In one of the key recent evolutions of the sector, each individual device carries a unique two-dimensional barcode (a data matrix) etched into the metal, for guaranteed identification. This information is read with a laser and fed into a central database (Instrument Management System), and allows accurate recording of the device’s processing history and test results throughout its life span.

Cleaning

The devices are then cleaned, disinfected and sterilised according to the most appropriate validated procedure. Techniques used include steam, fine lumen and mechanical cleaning, and the procedures are developed to be the most effective depending on the type of device and the application.

Inspection and tests

In addition to the scores of monitors and sensors in the cleaning and disinfecting process, there are also rigorous visual, mechanical and electronic tests to ensure that the hygienic and functional properties of the device are “as new”. Some reprocessors even use anatomical models to reproduce the operating conditions of the device in vivo, to test for suitability and safety.

Constant documentation

A key part of the new reprocessing sector is the thorough documentation that tracks each individual device through its whole reprocessing life, including several cycles. This has been made possible through the data matrices on the instruments, and through the centralised Instrument Management Systems (ISM) used by reprocessors. The benefits are manifold –

• each device is carefully tracked, and therefore only reprocessed a safe number of times
• any change in properties from one reprocessing cycle to the next can be identified
• each individual device can accurately be returned to the hospital it came from
• the whole process is transparent and accountable, in compliance with the reprocessors’ liability obligations

Sterilisation process (including sterile packaging)

After sterilisation, and drying in sterile air, the devices are packed with structural support if necessary, and sealed into bags.

Transport packaging

These are then packaged again to provide protection against transport stress, and these packages carry full labelling. The information on these includes all the manufacturer’s original data, as well as all relevant information relating to the reprocessor and the procedures that the device has undergone.

Reprocessing must be designed in such a way that the reprocessed medical devices neither endanger the clinical condition or the safety of the patient, nor the safety and the health of the users or that of any third party, provided that they are applied under the specified conditions and for the specified purposes. The purpose of reprocessing is, thus, to maintain reliable functionality and accomplish hygienic safety and, where necessary, sterility.

1. Risk management

Risk management is performed for every medical device to be processed, whereby the special aspects of the application and the reprocessing process are taken into account. Classification according to Recommendation by the Commission for Hospital Hygiene and Infection Prevention at the Robert Koch Institute and the Federal Institute for drugs and medical devices “Hygienic Requirements for Processing of Medical Devices” is included.

The procedure is orientated along the specifications of the DIN EN ISO 14971. Towards this end, the potential hazards are listed and evaluated for every medical device. Next, corresponding risk reduction measures are implemented and also evaluated. The result is a risk graph before and after the introduction of the risk reducing measures. Detailed risk analyses are thus provided for different product classes. A paragraph specifically relating to the respective manufacturer and the respective model provides details of the concrete engineering implementation, and the specific risks are determined.

For every medical device it must be specified how often it can be reprocessed with the corresponding process. This is accomplished by means of risk analysis, which is used as a basis for defining the critical steps within the process; for each of these critical steps the maximum possible frequency is determined within the framework of the validation process. It
is thus possible to withdraw a medical device from circulation at any time when it is no longer possible to guarantee its safety.

1.1 Potential hazards of infection

When assessing the infection risk, the following minimum points must be taken into account:

• Quantitative and qualitative analysis of the possible contamination following application;
• Type of contact with human tissue;
• Contaminations that may occur during transport and/or during reprocessing;
• Effective accessibility and wash-ability of all construction elements and surfaces of the medical device;
• Migration of residues of cleaning agents and/or disinfectants and/or reaction products.

1.2 Potential hazards due to changes in functionality

When assessing the functional ability of the medical devices, the impact of the respective application and the reprocessing procedure on at least these following aspects must be considered:

• Electrical characteristics (e.g. resistance, transmission rate);
• Mechanical characteristics (e.g. tensile strength, bending strength);
• Geometric characteristics (e.g. blade geometry, balloon profile);
• Optical characteristics (e.g. transmittance);
• Materials, particularly coatings (e.g. aging, corrosion, lubrication);
• Joints and possibly existing adhesives;
• Biocompatibility (e.g. toxicity due to leaching of low molecular components).

1.3 Potential hazards due to the processes applied

Furthermore, the impact of at least the following processes is considered:

• Cleaning (e.g. swelling);
• Disinfection (e.g. temperature, disinfectants, residues);
• Sterilisation (e.g. temperature, method, residues);
• Transport (e.g. shaking, temperature);
• Storage (e.g. total duration).
  

The techniques developed for cleaning and disinfection are adapted to the corresponding medical device and take into account at least the following points:

• Cleaning and/or disinfection are adapted to the requirements of the respective contamination;
• Unrestricted functionality is guaranteed;
• Interactions between the cleaning agent, disinfectant and steriliser are avoided;
• Avoidance of recontamination;
• Mechanical structure (dismantling properties) and special features of various models and/or different manufacturers;
• Ability to perform validation.

Every medical device is clearly and durably identified so that it can be readily traced back to all the applications and reprocessing procedures it has encountered during the entire course of its life cycle.

Identification is accomplished by means of laser technology applied directly to a safe position on the device itself. The identification consists of a specific serial number applied in optical characters and electronically encoded (data matrix or bar code).

Packaging is developed individually for every medical device; this packaging ensures that the product reaches the user intact, clean and, where required, in a sterile condition. It generally consists of the following elements:

• Mechanically protective packaging (e.g. inlays, packing rings, protective covers);
• Sterile packaging (provided with uncoated Tyvek and transparent film);
• External packaging (collapsible box made of GC1 carton).

The sterile and external packaging is provided with corresponding labels. An instruction leaflet is enclosed where necessary.

Every reprocessed medical device is to be provided with information that takes into account the training status and knowledge of the targeted user circle, and ensures that the device can be safely applied.

This information consists of details given on the label and, if necessary, on an enclosed information leaflet. The minimum required information includes the following:

• Details about the customer;
• Name of the product;
• Model and/or size;
• Manufacturer of the product;
• Where appropriate, the manufacturer's batch number or serial number;
• Note stating "Sterile", with reference to the sterilization procedure used;
• Date up to which safe application is possible;
• Required safety and warning notes;
• Where appropriate, special instructions on application (e.g. storage instructions);
• Where appropriate, the reprocessing frequency.

The reprocessing procedure and its effects on the product itself shall be validated for every medical device. This validation process shall consider all elements of the reprocessing procedure including cleaning, disinfection, packaging and sterilization, and it will consult the corresponding product relevant norms, guidelines and recommendations.

Furthermore, all apparatuses, devices and machines including the test facilities shall be incorporated into the validation process.

The purpose of the validation studies includes determining the process boundaries and the number of individual procedural steps. Frequently such tests are destructive or they are performed using appropriate test specimens. Possible tests include:

• Surface examinations,
  e.g. scanning electron microscope examinations (determining surface composition and surface roughness), atomic force microscopy AFM (determining surface topography), electron scanning chemical analysis ESCA (determining the chemical composition of the surface), boundary angle measurements (determining hydrophilic surface behaviour).
  
• Mechanical examinations,
  e.g. tensile strength, bending strength, burst pressure for balloon catheters, examination of reaction forces using in vitro models, endurance limit under cyclic loading conditions.
  
• Electrical examination,
  e.g. frequency response, dielectric strength, leak resistance.
  
• Material examination,
  e.g. ageing, corrosion, gel permeation chromatography GPC (determining molar weight and molar weight distribution, differential scanning calorimetry DSC (determining thermodynamic polymer structure, dynamic mechanical analysis DMA (determining mechanical polymer structure), spectroscopy within the IR and UV range (determining the chemical composition of the surface and volume phase), water absorption and swelling behaviour.
  
• Biocompatibility,
  e.g. cytotoxicity, subchronic toxicity, haemocompatibility, sensitisation, irritation.
  

A test schedule taking into account both functional as well as hygienic aspects shall be developed on the basis of the risk analysis and the validation. The functionality examination should be oriented towards the corresponding product-relevant norms, guidelines and recommendations. A 100% functionality test shall be provided for reprocessed medical devices.

7.1 Requirements with respect to functionality

The following functional tests are possible for accompanying the production process:

• Visual inspection, e.g. defect recognition, surfaces, blade geometry.
  
• Geometric examination, e.g. dimensional stability, contact-free laser measurement, concentric movement of rotating instruments.
  
• Mechanical functionality, e.g. dynamic friction, guide wire mobility for catheters, cutting ability, mobility of mobile construction elements.
  
• Electrical functionality, e.g. conductivity.
  
• Optical functionality, e.g. transmittance.
  

7.2 Requirements for cleanliness

With respect to hygienic safety, a final check is installed with the following visual and microbiological specifications:

• Following pre-cleaning, normal or normal corrected visual inspection must not reveal any outer contamination, encrustations, smut or films.• Following cleaning, normal or normal corrected visual inspection with 10-fold magnification must not reveal any outer contamination, encrustations, smut or films. This applies to all parts of the medical device.
• There must be no organic residues evident.

7.3 Requirements for hygiene

All of the germs present prior to the sterilization process exist in the form of particles after sterilization has been completed; in this form they can cause endotoxic reaction. For these reasons both a qualitative as well as a quantitative complete bacteria count are determined prior to sterilization. Prior to sterilization, the following limits must not be exceeded per device:

• Total colony count (aerobic mesophilic bacteria) < 1000 CFU
• Yeasts and moulds < 100 CFU
• Staphylococcus aureus < 10 CFU
• Streptococcus < 10 CFU
• Pseudomonadaceae < 10 CFU
• Enterobacteriaceae < 10 CFU

7.4 Requirements for sterility

Following sterilization there must be no micro-organisms on the medical device capable of
reproduction.

7.5 Requirements for sterilization residues

For ethylene oxide sterilization, EN ISO 10993:7 specifies that the sterilization residues must not exceed the following values:

7.5.1 Medical devices with continuous contact

• ethylene oxide
  0.1 mg / day;
  20 mg / first 24 hours;
  60 mg / first 30 days;
  2.5 g / product life.
  

• ethylene chlorohydrin
  2.0 mg / day;
  12 mg / first 24 hours;
  60 mg / first 30 days;
  50 g / product life.
  

7.5.2 Medical devices with long-term exposure

• ethylene oxide
  2.0 mg / day;
  20 mg / first 24 hours;
  60 mg / first 30 days.
  

• ethylene chlorohydrin
  2.0 mg / day;
  12 mg / first 24 hours;
  60 mg / first 30 days.
  

7.5.3 Medical devices with short-term exposure

• ethylene oxide
  2.0 mg / day.
  

• ethylene chlorohydrin
  12 mg / day.
  

7.6 Requirements with regard to endotoxin load

A LAL test (Limulus Amebicide Lysat) is used for detecting endotoxin gram-negative bacteria as evidence for substance-independent pyrogenic burden. Thereby the limit value of 20 USP endotoxin units per product must not be exceeded.

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• General requirements for the reprocessing of medical devices