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Ellison C. Pierce, Jr., M.D.,
Associate Clinical Professor of Anaesthesia, Harvard Medical School,
Chairman Emeritus, Department of Anaesthesia, Deaconess Hospital,
Boston, MA
ASA entered the world of standards writing in
the mid 80's with Burton Epstein as Chairman of the new Committee
on Standards. Since then anesthesiologists have been lauded repeatedly
by other specialties for leadership in patient safety. More recently
ASA has moved from issuing standards to writing evidence-based guidelines
for specific procedures or clinical situations, using stringent
epidemiological methodology. Once again, our efforts are attracting
attention from other specialties, particularly our rigorous approach
to literature analysis and consensus formation. Robert Caplan directs
the scientific and procedural aspects of ASA guideline development
and James Arens is Committee Chairman.
Expansion of discussions of human error in anesthesia to the larger
arena of human performance is an exciting development, exemplified
by the 1991 APSF and Food and Drug Administration jointly sponsored
multi-disciplinary conference on human performance. David Gaba has
become a leader in utilizing human performance knowledge, specifically
in "breaking the chain of accident evolution", examining
anesthesia mishaps along the lines of the normal accidents model
in industry, as described by Perrow. (34) (35) Nuclear power, aviation,
and chemical systems that combine complex interaction and tight
coupling are likely to have accidents in spite of efforts to prevent
them. Simple incidents may progress to critical incidents, or further
to a negative outcome. Gaba provides convincing arguments that we
have much to gain from the industrial approach to accident prevention.
In particular, prevention of the progression from simple to critical
incidents may be enhanced by better detection of simple incidents,
improving one's ability to construct and use mental maps or "overviews"
of complex processes, improving backup tools for recovery from simple
failures, and disseminating proper protocols for handling of rapidly
propagating incidents.
How can human performance be improved? Howard Schwid has provided
a key insight in his studies of simulated events such as anaphylaxis
and cardiac arrest. (36) Typically, practitioners develop "fixation"
errors (i.e. cognitive failure to revise a therapy plan in the face
of contradictory evidence). Many investigators and educators now
believe that human performance can best be enhanced by the specialized
training afforded by realistic simulators. Two commercial models
of anesthesia simulators are now available. The CAE Patient Simulator,
designed using technologies developed separately by Gaba (Stanford)
and Schwid (Seattle), is in use at Harvard, Toronto, Pittsburgh,
Stanford, and Seattle. The Loral Simulator, developed at Gainesville
by Michael Good and associates, is functioning at Gainesville, Mount
Sinai (New York City), Augusta, Hershey, Chapel Hill, Rochester,
and Nashville.
Use of simulators as training devices, then, is expanding rapidly
for teaching basic anesthesia skills, for introducing crisis resource
management to individual anesthesiologists and operating room teams,
and for investigating the basic foundations and limitations of human
performance.
Time constraints will not allow me to examine in more detail human
performance and patient safety as it relates to the anesthesia workstation;
anesthesia resident selection; the role of sleep, fatigue, and aging;
and methods for the scientific investigation of anesthesia accidents.
I call your attention to the 1995 ASA Meeting Scientific papers
section, "Patient Safety, Epidemiology, History, and Education",
at which 139 papers are scheduled to be given. Ten years ago there
was not even a section on these subjects. In addition there is a
Tuesday morning panel on Human Performance.
We should now examine whether anesthesia outcomes are better today
than they were 10, 20, 30 or 40 years ago. Are J.S. Gravenstein,
John Eichhorn and Cheney correct when they say, "yes".
Let us first agree that we are anesthetizing sicker patients for
more complicated surgery now than in the past.
When, in 1989, John Eichhorn reviewed some 1,000,000 anesthetics
in ASA Physical Status I and II patients administered at the various
Harvard hospitals between 1976 and 1985, he noted eleven major intraoperative
anesthesia accidents (two cardiac arrests, four cases of severe
brain damage and five deaths). (37) The most common cause (seven
out of the eleven) was an unrecognized lack of ventilation. He believed
these seven as well as one other in which oxygen was discontinued
inadvertently would have been prevented by "safety monitoring."
He then noted that after the institution of the Harvard monitoring
standards in 1985 out of the next 300,000 anesthetics there were
no major preventable intraoperative anesthesia injuries. He concluded
that this was a considerable improvement in outcome related to the
institution of monitoring with capnography and pulse oximetry.
In an accompanying editorial, Fred Orkin conceded that "the
death rate related primarily or solely to anesthesia care has decreased
markedly during the past four decades...". (38) His principal
concern was "that we have yet to learn the true benefits and
risks of newer monitoring equipment"...."the critical
need is to learn more about the relationship between what we do
and patient outcome". Practice standards..."must be shown
to produce a net benefit before (they become)...part of clinical
practice".
Others disagree with Keats and Orkin. Among them are J.S. Gravenstein
who says, in essence, that it is important to recognize that many
changes (not to call them advances) in medicine have been introduced
without the benefit of controlled scientific studies (personal communication).
(39) Their impact on the quality of care or outcome cannot be measured.
However, in the absence of measurable effects we cannot conclude
that there are no effects, especially good effects. So much in medicine
over the years has not been measurable. Who, for example, in anesthesia
would use a high spinal to anesthetize a patient in hypovolemic
shock. We have had no scientific prospective studies to prove that
is harmful. Is it always necessary to insist upon rigorous scientific
proof for each and every aspect of care?
No, we cannot prove in a scientific manner that anesthesia is safer
today, although, I believe that most anesthesiologists who practiced
years ago will eagerly agree that it is. Moreover, it is unlikely
that funds will ever be available to do definitive prospective outcome
studies. Beginning in the early 80's anesthesiologists in New Jersey,
California, and Arizona worked closely with their insurance companies.
I continue to argue that the significant decreases in relativity
factors for anesthesia medical liability premiums are due to the
marked decline in the severe anesthesia negative outcomes --- death
and permanent brain damage. Certainly the insurance industry concurs.
Let us look once again at the figures. At Harvard the current relativity
is 2.5 instead of 5.0, as it was in 1985. (Tables 5 and 6) Hence
the current premium is $10,000 instead of the $20,000 it would be
if the relativity were still 5.0. If each of us saves $10,000 per
year in insurance premiums (as at Harvard), that is $300,000,000
for the entire country. But, as I have said repeatedly (and I often
choke up when making this comment), the overall incidence of anesthesia
mortality is not important when the death due to an unrecognized
esophageal intubation is in your own 18 year old child undergoing
odontectomy. In the last year or so I have heard of several accidents
resulting in death or severe brain damage --- probably due to errors
on the part of the anesthesiologists.
As the time allotted to this lecture nears its end, I would like
to offer a general observation and some advice for the future. Patient
safety is not a fad. It is not a preoccupation of the past. It is
not an objective that has been fulfilled or a reflection of a problem
that has been solved. Patient safety is an ongoing necessity. And
it must be constantly sustained by research, training, and daily
application in the workplace.
In fact, I fear that we may be entering an era that could easily
undo many of the gains that we now cherish so highly. This is the
era of cost-containment, production-pressure, and bottom-line decision
making by corporate deal-makers. The forces underlying this new
era are driving us to be leaner, faster, and cheaper. To some extent,
these changes may bring a measure of immediate health and vigor
to the practice of medicine. But they also pose a worrisome threat.
If we try to meet financial challenges by short-cutting our daily
attention to patient safety, or by minimizing our long-term commitments
to education and research, we may not be able to carry forward the
gains of the immediate past or pursue the exciting insights and
innovations that are just now emerging. As Nik Gravenstein said
so succinctly in the most recent issue of the APSF Newsletter, "We
must raise our voices in support of safety. (40) If we do not, safety
will take a backseat to economy."
My friends and colleagues, our efforts to improve the safety of
anesthesia have merely begun. Significant challenges await us, perhaps
more so in the coming years than in the past four decades that I
have had the pleasure and privilege to describe to you. But we must
not retreat; we must not loose our collective resolve. Patient safety
is truly the framework of modern anesthetic practice, and we must
redouble efforts to keep it strong and growing.
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