How to manage the medical device sterilization process according to ISO 13485:2016

Sterilizing medical devices is of vital significance in the medical sector. Even so, at various places in the world, surgical devices are not properly sterilized. As a result, many patients die, while many more are diagnosed with various infections after surgery, and other complications also arise due to a lack of proper sterilization.

Sterilization is a process that is mandatory for the majority of medical devices, quite often required by regulatory authorities. It is a process to make the product free from bacteria and any other microorganism that cannot be eliminated by regular cleaning processes. Therefore, sterilization requirements have been addressed separately in ISO 13485:2016. Surgical instruments are often reused, but after surgery they are contaminated by microorganisms. So, in order to reuse such medical devices after surgery, effective sterilization is necessary. There are various methods of sterilization available, which include autoclaving, radiation, ethylene oxide (ETO) sterilization, chlorine dioxide sterilization, hydrogen peroxide sterilization, and others.

Sterilization offers three safe conditions for surgery

Safe conditions for surgery refer to a condition in which the patient, the medical devices, and the environment exhibit a minimal risk of surgery-induced diseases and other medical issues. Safe medical conditions are extremely important during surgery, because these conditions ensure the patient’s safety during the surgical process itself. Medical sterilization is therefore critically important because, in surgery, it enables three different medically safe conditions:

  1. Sterilization stops the growth of bacteria on instruments, ultimately preventing the transfer of bacteria to the patient.
  2. Sterilization stops the spread of deadly diseases, like HIV, from instruments to patients.
  3. Sterilization prevents infection that could require additional surgery.

Requirements for sterilization, and how to comply

Sterilization requirements are spread throughout the whole ISO 13485:2016 standard. Let’s see a few of the most important ones.

Sterile Medical Device (Clause 3.20) of ISO 13485:2016 states that sterility requirements of each medical device can be subject to applicable regulatory requirements. For example, a regulatory authority in the region in which you supply medical devices demands ethylene oxide sterilization for a specific medical device – so you have to ensure that the requirement of the regulatory authority is met by performing ethylene oxide sterilization.

Contamination control (Clause 6.4.2) addresses the prevention of contamination after the devices are sterilized. The controls may include dust collectors and ventilation systems, and are monitored through tests of air quality at a defined frequency in assembly and packaging areas after the sterilization.

Particular requirements for sterile medical devices (Clause 7.5.5) sets two direct requirements:

  • Records of process parameters of sterilization of each batch – Sterilization process parameters need to be recorded for each batch. Process parameters include pressure within sterilization unit, temperature within sterilization unit, gas flow rate in the unit, operator name, and environmental conditions like humidity, etc. All process parameters that can affect product quality, in terms of sterilization, have to be recorded.
  • TraceabilityAll batches of sterilization should be traceable. This means that you can trace back the packed, shipped, and customer-returned instruments through the sterilization records (in which they were recorded).

Requirements for validation of processes for sterilization and sterile barrier systems (Clause 7.5.7) sets two requirements:

  • Validation of sterilization processes – A procedure must be developed to address validation of sterilization processes. Validation will be necessary if there is a change or addition to a process or a product. For example, you installed a chlorine dioxide sterilization unit in your sterilization department. Before going into regular production, you must validate this equipment as to whether it removes microorganisms from bio-contaminated instruments, or not.
  • Validation of sterile barrier system – A sterile barrier system is a system that includes minimum adequate barriers to protect medical devices from microorganism contamination; this can be done with a closed controlled room containing bio-sensors for the packaging of medical devices, sensors and alarms indicating there is bio-contamination within the room, and stoppage of the process until the room environment is compliant. Such sterile barrier systems need to be validated with a defined procedure; for example, devices are tested for micro-biological contamination after going through these systems as part of the validation process. The sterile barrier system should be validated again if there is a change to any control of the barrier system, or a change in the design of system (for example, changes to the bio-sensors).

Effective sterilization management builds customer trust

Medical devices, in the absence of sterilization, pose many different health risks that simply can’t be tolerated. Fatalities can result in cases of microorganisms infecting the human body. Therefore, the ISO technical committee rightfully reviewed the existing sterilization requirements in the previous version, and added new controls in ISO 13485:2016. These new requirements will increase competition among both manufacturers and suppliers, because this is how you can actually build customer trust.

If a process of sterilization goes wrong in some of its aspects, and is reviewed by the manager later that day or another day – the manager can correct the non-conformity, because the non-conformity can be easily managed due to adequate traceability in the sterilization records. All of those production lots can be stopped right there while a correction and corrective action can be made. The standard not only addresses requirements of the sterilization process, but it also acts a guideline for how to prevent and safeguard the sterilization process in processes that follow. This has increased the suppliers’ ability to gain customer satisfaction.

Use this free Diagram of ISO 13485:2016 Implementation Process in order to control ISO 13485 implementation.