Biomedical Engineering Reference
In-Depth Information
rules, these rules are not necessarily abandoned. The workers can reason
from rules that might be applicable in the absence of any 'deviant' char-
acteristics. For example, in oncology, therapeutic guidelines do not take
into account some of the patients' medical characteristics (medical history,
comorbidities, etc.). Similarly, there are no guidelines for the treatment of
breast cancer in men. Yet, doctors reason from the guidelines that would
apply if the characteristics we have just mentioned were absent, to deter-
mine the therapeutic strategy that is best suited to a particular case (since
the guidelines guarantee the effectiveness of the treatment). In radiother-
apy, when faced with a nonnominal situation for which there is no formal
rule available to guide action (e.g. a breakdown of imaging equipment,
lack of any accessories to position the patient correctly, etc.), professionals
rely on their experience in the profession or in the department to solve
problems. Thus, they construct metarules for action, based upon their
knowledge of the patient in question and of the current stage of the treat-
ment, of the behaviour of colleagues, of the availability of resources, and
of the wish to develop a strong safety culture.
Be that as it may, it can be noted that the rules that are created rely
on the entire set of available resources: existing formal rules and rules
derived from individual or collective experience. These rules can become
stabilized following the repeated occurrence of similar situations.
Technical operation is deficient or the rules
are not adhered to by all workers
Managed safety also steps in when the context that was originally foreseen
for regulated safety is not present. This is the case, notably, for technical
failures (for example, equipment breakdowns) or in the case of cascades
of rule violations. In radiotherapy, running late leads to violations of the
control rules prescribed by the organization: patient files are filled in in
a hurry, and successive controls are performed too quickly, or even not at
all. For example, radiotherapists may decide not to validate the treatments
they prescribe when these treatments match the protocol very closely and
are therefore viewed as 'simple', or when there is no time to do so. To gain
some time, a radiotherapist will only validate the treatment during the
first weekly consult with the patient, i.e. 1 week after the beginning of
the treatment. This nonnominal situation leads to a sequence of actions
of recovery on the part of the x-ray operators, seeking to return to a nomi-
nal situation where the rule may be applied. The x-ray operators then try
to contact the doctors to request the validation of their file. If this request
is successful, then safety in action has made it possible to return to a nor-
mal situation. Hence, managed safety steps in to support regulated safety.
