Volume 24 - The Society for the Advancement of Anaesthesia in ...

VISITING PROFESSOR
In addition to misleading information, memory can
also be altered when we fill in the gaps of our memory
for an experience with guesses or thoughts about how
it probably was (5, 6) . These guesses, then, similar to the
misinformation provided in questions or through other
means, are stored with the gist of the event and may
become part of the memory at the next construction
(recalling) of the event.
Think of the medical and dental fields as having their
own cultures. They definitely have their own language
and terminology, their own specific physical space, as
well as clothing and realms of possible experiences and
behaviours. The experience of a patient, new to and
unfamiliar with this culture, parallels the behaviour of
someone who has travelled to a foreign country where
they are unfamiliar with the language, customs and
behaviours of the new culture. As such, the different
and unfamiliar events will be interpreted and encoded
differently from how they actually occurred. In addition
to the influence schemas have on encoding, their use
may also result in memory errors created when we begin
filling in the gaps in the construction of the memory.
Perhaps you really do not recall the injection you received,
but your sedation schema dictates that the anaesthesia
was administered by an injection; therefore, you report
you received an injection and possibly even that you
recall being given an injection. Then when your spouse
asks you, ‘How painful was the shot?’ you add ‘pain’ to
the event of injection and restore that to be retrieved at a
later date. Essentially, a new, false memory has now been
created, that of a painful injection.
Failed sedation, from the patient’s perspective, can be
incredibly traumatic. When identifying elements of
patient satisfaction or dissatisfaction from a sedation
experience, Coyle and colleagues (7) found that memory
for the procedure significantly impacted on satisfaction
reports. Of the patients dissatisfied with the operation,
20.9% recalled having pain. Additionally, when exploring
patients’ memory of the operation, 32.1% reported
being awake, 6% of those being unable to communicate.
Particularly if the clinician is unaware of the patient’s
state, care may not be taken in topics of verbal
discussions, techniques that are quicker rather than less
painful may be chosen and unfamiliar noises may
become encoded as terrifying and negative rather than
routine. With this increased level of emotion, the patient
will keep thinking about these facts, strengthening
their recall possibilities, and in lieu of knowledge of the
procedural ‘culture’, uncertainty may be stored as fear
and pain.
Q.) I want to give the pre-operative instructions for my
patient in the best possible way so that they will be able
to remember them, tell their spouse what to expect,
remember to arrange a ride, not eat or drink before the
procedure, be on time, wear loose clothing, short sleeves
for cannula placement, not be nervous, etc. What
processes are at play and how do I capitalise on them?
To be remembered, information must first be encoded.
Although it sounds like common sense to say this, many
people remain surprised about certain information
they are unable to recall. We use schemas to encode
information.
A schema is a cognitive structure that provides a
meaningful framework for organising information. To
build schemas, we use knowledge and assumptions of
people, objects, events and the world, and construct
the frameworks using the main ideas, or the gist of the
information. While not every detail is contained in the
schema, details are easily added back into the recalling
of the event using this framework. Schemas aid in the
efficiency of encoding, storage, and the retrieval of
information. Very young children have poorer memory
than older children, as they are unable to extract the
gist of an event or information but rather attempt to
remember it verbatim. As we age and develop cognitively,
we develop the ability to extract the gist from an event to
be remembered.
Although it is time-intensive, the clinician might take
this opportunity to help the patient build a sedation
schema. Teaching people what is important in the
procedural process essentially instructs them as to what
they should pay attention to. In building the schema ask
whether they have had pre-operative instruction in the
past, and whether they know what to expect. Do not
make the assumption, if a patient says she has been in
the dental surgery before and knows what to do, that her
recall of your pre-operative instructions will be better
than a patient getting them for the first time. Previous
information (instructions from a prior session) may
interfere with your patient’s ability to recall your more
recent instructions. This proactive interference occurs
especially when subject matters are so very similar, so that
it is easier for the learning of old material to interfere
with the patient’s ability to recall the new instructions.
In order to create conditions most likely to result in
the highest level of adherence to the pre-operative
instructions, the instructions first need to be learned
or encoded so that at the appropriate time they will
SAAD DIGEST | VOL.24 | JANUARY 2008 19