Introduction
It is appropriate to have another update of the Guidelines for the Assessment of Cardiovascular
Fitness in Canadian Licenced Aviation Personnel, although there have been few significant
developments in the field since the last one published in 1995. Most importantly perhaps, the overall
population of aviators in Canada is aging. Whereas in 1986, half (49%) of all pilots were 40 or more years
old, in 2001 that proportion was up to 63% and among professional pilots the proportion rose from
32% to 50%. Consequently the likelihood of a cardiovascular event is increasing. While age alone
cannot be used as a discriminating factor, it must be taken into consideration when assessing overall risk.
A review of Canadian aviation medical guidelines in 1996 determined that current criteria adequately take
into consideration the impact of age on risk. Nevertheless examiners must be mindful of even
normal physiological changes associated with aging and their possible impact on flight safety.
Aviation Medical Standards as laid down in Annex 1 to the Convention on
International Civil Aviation by the International Civil Aviation Organization
(ICAO) to which Canada is a contracting state, identify broad medical conditions
that on the basis of expected risk of incapacitation disqualify a pilot from
flying an aircraft. Such conditions, e.g., acute ischemic syndromes are
reportable to Transport Canada and result in immediate revocation of medical
certification. In countries where the standards are applied strictly, affected
pilots may never return to flying. Such a strict policy may be unfair to those
aviation personnel in whom the risk of sudden incapacitation becomes acceptably
low as a result of risk factor modification or rehabilitation including some
therapeutic interventions. Our ability to predict risk in an individual is
improving as experience with groups bearing similar risk profiles increases.
Progress with the assurance of a safe flying environment e.g. through widespread
incapacitation training, has also allowed more tolerance of certain
medical conditions. The risk of a fatal accident occurring as a result of
medical incapacitation is dependent on a number of factors. These include the
amount of time spent flying, the risk of an incapacitation occurring at a
critical phase of flight and the risk that such incapacitation will inevitably
result in a catastrophic accident. All of these factors must be taken into
consideration in addition to the known medical risk of a given medical
condition. Experience with cardiac disease in the general population along with
experience with simulators allow the estimation of risk in a fashion similar to
that used by structural engineers. It can be rationalized that an annual risk of
incapacitation up to 2%* due to a medical condition can be tolerated in an
unrestricted flying environment, as that would translate into an acceptably low
risk of a resulting fatal accident. Where there is insufficient precision in
estimating risk for the medical condition of a given applicant, then a
determination of medical fitness should err on the side of caution.
As with the previous guidelines, a one day workshop to review and update
existing guidelines on cardiovascular fitness was organized in Ottawa on
December 3rd, 2001 with the participation of Regional Aviation Medical Officers,
cardiovascular and aviation medicine consultants and staff from the Civil
Aviation Medicine Branch, Transport Canada.
In this edition we have also tried to clarify and ambiguities or
inconsistencies. We continue to welcome your suggestions to make the guidelines
a practical document that is supported by the best scientific evidence
available.
Andreas T. Wielgosz
James M. Wallace
* A 2% risk of incapacitation includes a 1% risk due to a fatal occurrence as well as a 1% risk due to an
incapacitating but nonfatal occurrence.
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