Class IIa Medical Devices (EU MDR)

The European Union Medical Device Regulation (EU MDR) is a new set of rules that will apply to medical devices marketed in the European Union to ensure the quality and safety of the medical device.

According to Article 51 of the MDR, medical devices are classified according to their intended purpose and inherent risks into four groups, class I, IIa, IIb and III. The 22 classification rules are listed in the Annex VIII of the MDR Act. The classification is based on four factors, the duration of contact of the device, the degree of invasiveness, the anatomy affected, and whether the device is active or otherwise. The regulatory requirements for the devices vary according to their inherent risk, with stricter regulations for the devices posing a higher risk to the patient.

Class IIa medical devices pose an intermediate risk between class I and class IIb devices.  They include some non-invasive, some invasive and some active devices.

Non-invasive devices included under this class include the followings:

  • Non-invasive devices that store or channel blood, body liquids like plasma, cells or tissues like cornea, sperms and human embryos, which are intended to be introduced into the body. Devices used to channel blood are used in blood transfusion or extracorporeal circulation and fridges intended to store blood and tissues are also classified as class IIa devices.  A notable exclusion is blood bags, which are classified as class IIb devices.  
  • Non-invasive devices intended to modify the composition of biological material through processes of filtration, centrifugation or exchange of gases or heat. These may include devices that filter particles and emboli from the blood, remove carbon dioxide, warm or cool the blood in an extracorporeal circulation or centrifuge the blood to separate its individual components like plasma, red blood cells or white blood cells.
  • Non-invasive devices that are used to cover wounds and help in healing by primary intent, where the edges of the wound are in contact with each other. These devices like adhesives, polymer film dressings or hydrogel dressings manage the micro-environment of injured skin or mucous membrane by controlling the level of moisture, humidity and temperature, levels of oxygen and other gases and pH values or by other physical means.

Some invasive devices that are those passed through a natural or artificial opening into the body are included in class IIa. These include:

  • Those used for short term, that is continuously for between 60 minutes and 30 days. Examples of such devices include short-term corrective contact lenses used on the eyes, dental devices like orthodontic wires, fixed dental prostheses and fissures sealants, tracheal tubes with are attached to surgically made tracheal openings, vaginal pessaries passed into the vagina and indwelling catheters and urinary stents that are intended for short-term use.
  • Those connected to class II or III devices used over short term. These may include powered nasal irrigators, fibre optics in endoscopes connected to surgical lasers, suction catheters or tubes for stomach drainage or dental aspirator trips.
  • Those used over long term, that is, for more than 30 days at a stretch up to the throat (pharynx), nose, or the external ear canal

Some surgically invasive devices are also classified under class IIa devices. These include:

  • Surgically invasive device for transient use like needles including those for suturing and those attached to syringes, lancets, single use scalpels and blades, staplers, surgical swabs, belong to class IIa. It is important to note that reusable surgical instruments belong to class I and are excluded here. In addition, devices that emit ionizing radiation, have a biological effect, are absorbed or administer a medicinal product in a potentially hazardous way, or in direct contact with the heart, central circulatory system or the central nervous system are also excluded.
  • Surgically invasive devices for short-term use, that is between 1 hour and 30 days. Important exclusions are devices which gives ionizing radiation, have a biological effect, are absorbed or administer a medicinal product in a potentially hazardous way, or in direct contact with the heart, central circulatory system or the central nervous system.
  • Implantable devices and long-term surgically invasive devices to be placed in the teeth, are classified as class IIa. These include bridges and crowns, dental filling materials and pins, dental alloys, ceramics and polymers.

Active therapeutic devices are devices that use energy for treatment. Some active therapeutic devices that are not hazardous in nature, do not affect the performance of class IIb or active implantable devices, or emit, control or monitor ionizing radiation for therapeutic purposes are classified as class IIa devices. These devices may use electrical and/or magnetic and electromagnetic energy, for example, muscle stimulators, external bone growth stimulators, TENS devices and eye electromagnets, heat energy like cryosurgery equipment, mechanical energy like powered drills, light energy like phototherapy for skin treatment and treatment of jaundice in newborns, sound like hearing aids and ultrasound like equipment used for physiotherapy.

Software intended to provide information which is used to take decisions with diagnosis or therapeutic purposes, or monitor physiological parameters is classified as class IIa. The decisions should not have a potentially serious or lethal effect on the health of the patient, in which case it will be assigned to a higher class.

Other devices that are included in class IIa are:

  • All devices intended specifically to be used for disinfecting or sterilising non-invasive, such as sterilizers and washer disinfectors but not invasive, medical devices or contact lenses
  • Devices specifically intended for recording of diagnostic images generated by X-ray radiation like x-ray films and photostimulable phosphor plates,
  • Devices that record the movement of a radiopharmaceutical throughout the body like magnetic resonance equipment, diagnostic ultrasound, gamma cameras, and PET scans
  • Devices that are used to monitor vital functions in the absence of a life-threatening situation like electronic thermometers, electronic stethoscopes, electronic blood pressure monitoring devices. ECGs and EEGs.
  • Devices incorporating or consisting of nanomaterial with a negligible potential for internal exposure
  • Devices that contain substances that are intended to be introduced into the human body in the nose, in the mouth up to the pharynx or applied to the skin and that are absorbed and achieve their intended purpose locally or on those cavities

This article is for informational purposes only and not intended to replace the relationship between the doctor and the patient. It should not be used for self-treatment by patients or by doctors to treat patients. Consult your doctor before using any of the above information.


Published on: 7/9/2020

Updated on 17/11/2020