Medical devices have been used in hospitals even before clinical engineering or biomedical engineering departments ever existed. However, a clear definition of “medical device” consistent with Clinical Engineering’s scope of services is a bit more difficult to come by. This article has been put together to explore the different definitions that exist for medical devices, and how these can be applied to Clinical Engineering (CE).
When asked to define a medical device, a clinical engineering professional might mention electrical or mechanical energy transfer used to diagnose or treat a patient, such as in an x-ray system or a cardiac monitor. Other healthcare professionals might think that medical consumables, such as a catheter or a tongue depressor, are more what come to mind when they hear the words “medical device”. These words might also mean something different to a veterinarian or a dentist, who both use consumables and electrical treatment devices in their practices.
Let’s first consider Health Canada’s definition of a device, as per the Food and Drugs act of Canada:“device” means an instrument, apparatus, contrivance or other similar article, or an in vitro reagent, including a component, part or accessory of any of them, that is manufactured, sold or represented for use in:
- diagnosing, treating, mitigating or preventing a disease, disorder or abnormal physical state, or any of their symptoms, in human beings or animals,
- restoring, modifying or correcting the body structure of human beings or animals or the functioning of any part of the bodies of human beings or animals,
- diagnosing pregnancy in human beings or animals,
- caring for human beings or animals during pregnancy or at or after the birth of the offspring, including caring for the offspring, or
preventing conception in human beings or animals;
however, it does not include such an instrument, apparatus, contrivance or article, or a component, part or accessory of any of them, that does any of the actions referred to in paragraphs (a) to (e) solely by pharmacological, immunological or metabolic means or solely by chemical means in or on the body of a human being or animal;
As we can see from the above definition, it is evident that this is a broader definition than what is necessary – and used – in Clinical Engineering. CE departments aren’t responsible for maintaining devices used in the diagnosis and treatment of animals. If we dig deeper in Canadian legislation, we find that the Food and Drugs Act does make reference to an annexed regulatory document, the Medical Devices Regulations. Within this document, a medical device has the following definition, where “Act” refers to the Food and Drugs Act:
“medical device” means a device within the meaning of the Act, but does not include any device that is intended for use in relation to animals.
With this new definition, we are coming closer to what a medical device really means in Clinical Engineering. We have ruled out drugs and devices intended for use in relation to animals. However, when re-reading the above definitions, we can clearly see that something is still missing: we need to be able to distinguish between a CE device and a medical consumable (e.g. between a cardiac monitor and a tongue depressor). This can be achieved using another definition from the Medical Devices Regulations:
“active device” means a medical device that depends for its operation on a source of energy other than energy generated by the human body or gravity. A medical device that transmits or withdraws energy or a substance to or from a patient without substantially altering the energy or the substance is not an active device.
Now we find ourselves with a Health Canada definition that most closely resembles the definition of a medical device used in CE. Exceptions can still exist: for devices that do not fall into the above definitions of an active medical device, but that might still be within CE scope of services (e.g. nurse call systems, Dictaphone, scope washers, electrodes, etc.); or for devices that do fall into the above definitions but are not within CE scope of services (e.g. pacemaker, implantable loop recorder, etc.).
So, next time you’re having a discussion with hospital staff, keep in mind that their definition of a medical device might be different than yours; and a lot of confusion can be avoided through clear and respectful communication!