Chapter 83
- Human Performance and Patient Safety
- Marcus Rall
- David M. Gaba
This chapter deals with the most important component of every
anesthetic: the human performance of the anesthetist and its relation to patient
safety. Anesthesia is an intrinsically hazardous undertaking, but as hazardous activities
go, its track record is indeed a model for health care.[1]
[2]
The Institute of Medicine asserts: "Anesthesia
is an area in which very impressive improvements in safety have been made."[3]
[4]
However, the theory of organizational safety
teaches us that safety is a never-ending process; any patient harmed by an anesthetic
is one patient too many. In this sense, Cooper and Gaba[1]
wrote: "Anesthesiologists should remain aware of the hazards they still face, take
pride in having been the leaders in patient safety efforts, and stay motivated to
continue the pursuit of 'no harm from anesthesia' with the passion it still demands."
As most of the work on human performance (and also on simulation)
has been started and has focused on anesthesiology in the operating room (OR), this
chapter deals
primarily with aspects of performance and safety in the OR setting. Nevertheless
most of the same principles and issues are relevant to the post-anesthesia care unit
(PACU), the intensive care unit (ICU), the emergency department, and to a lesser
degree to pain therapy and other domains of importance to anesthesiologists. For
readers with a special interest in the ICU a selection of references are given as
a starting point.[5]
[6]
[7]
[8]
[9]
[10]
[11]
[12]
[13]
[14]
[15]
[16]
[17]
[18]
[19]
[20]
[21]
[22]
[23]
[24]
[25]
The safe conduct of anesthesia depends on the appropriate application
by the skilled anesthetist of knowledge concerning the surgical procedures, the physiology
of patients during and after anesthesia, the characteristics of anesthetic and adjuvant
drugs, and the means of monitoring the patient and the life-support equipment throughout
the perioperative period. In this chapter, the term anesthetist
refers to any anesthesia practitioner, whether a physician or a certified nurse anesthetist.
Traditionally, it has been assumed that an adequately trained anesthetist automatically
performs appropriately. Deviations from optimal outcomes were understood to be due
to imperfections in the art and science of anesthesia, leading to a heavy emphasis
on the scientific and technical aspect of anesthesia training and care. More rarely,
adverse outcomes were ascribed to negligence or incompetence on the part of the anesthetist.
Today, there is a more complete understanding that anesthetists
themselves, both as a profession and as individuals, have strengths and vulnerabilities
pertaining to their work environment. The performance of human beings is incredibly
flexible and powerful in some aspects, but very limited in others. They are vulnerable
to distractions, biases, and errors. This chapter surveys some of the human characteristics
that define the performance of the anesthetist. The domain of the anesthetist is
very challenging, being every bit the equal of domains, such as aviation, that more
readily capture the public's imagination. The past 15 years have seen new research
concerning the nature and limitations of professional judgment and decision-making
in this dynamic and complex world. Chapter
84
, "Patient Simulators," explores developments in simulation technology
that have contributed to this research and that may open new opportunities to prepare
anesthetists to handle the challenges that they will face in their work.
The literature related to human performance is vast (standard
reference works are available[26]
[27]
[28]
[29]
[30]
[31]
[32]
[33]
[34]
[35]
[36]
[37]
[38]
), and
this
chapter samples only a portion of it as it most closely relates to the work of anesthetists.
Moreover, this chapter does not deal to any great extent with human-machine interactions
and the physical design of the work environment. These aspects of human factors
or ergonomics in anesthesia have considerable importance in their own right. The
reader is referred to several publications that review these issues in detail.[39]
[40]
[41]
[42]
[43]
[44]
[45]
[46]
[47]
[48]
[49]
[50]
[51]
[52]
For example, the application of human factors in the design of
a resuscitation trolley is described by Donchin.[53]
Furthermore, a new U.S. Food and Drug Administration (FDA) program establishing
a Medical Device Surveillance Network aims at early identification of device problems
by health care professionals and the reporting of serious low-frequency events.[54]
Although optimal design is the best means to improve human-machine
interaction, another interesting aspect is that of markings and warnings: How should
we mark equipment that is found to be faulty but cannot be removed immediately from
the clinical environment? Similarly, how can we best provide warnings about specific
hazard-prone procedures? Rogers[55]
provided an
in-depth analysis on the design of warnings and factors influencing the aspects of
the warning process, stating that a good warning has the elements of "Notice, Encode,
Comprehend and Comply," thus consisting of (1) a signal word, (2) the description
of the type of hazard, (3) the consequences of the hazard, and (4) instructions on
how to reduce or eliminate the hazard. An example of a well-formed warning would
be: "Attention! This anesthesia cart has not been refilled.
Some equipment and drugs are missing. Refill and check before use."
