PERFORMANCE-SHAPING FACTORS
With a few exceptions, the foregoing discussion of the performance
of skilled anesthetists has assumed that they are normally fit, rested, and acting
in a standard working environment. Experience in human performance in the laboratory
and other domains suggests that there are profound effects on the abilities of even
highly trained personnel from internal and external performance-shaping factors.
The degree to which performance-shaping factors affect the overall performance of
anesthetists and the outcomes for patients is highly uncertain. In extreme cases,
such as profound fatigue, there is no question that these factors can result in severe
degradation of the anesthetist's performance or even complete incapacitation. However,
these extreme conditions are quite unusual, and it is unclear whether the levels
of performance decrement likely to be induced in typical work situations have any
significant effect. Although the practice of anesthesia does require an attentive
and skilled individual, it does not require peak human performance. It would be
unrealistic to expect peak performance for every anesthetic regimen because there
are on the order of 60,000 anesthetic regimens administered each day in the United
States by a total of approximately 40,000 to 60,000 anesthetists.
With these caveats in mind, however, there are several performance-shaping
factors that are potentially of sufficient magnitude to be of concern. Ambient noise,
music, fatigue and sleep deprivation, aging, illness, drug use, and attitudes are
discussed later. Several other factors that are not discussed include the level
of illumination and environmental temperature. These can be shown to have a performance-shaping
effect in the laboratory,[27]
[326]
but it is uncertain how much they affect performance in the OR. Currently, the responsibility
for assuring fitness for duty rests solely with the individual clinician. In HROs,
the institution implements measures to control performance-shaping factors.
Ambient Noise and Music in the Operating Room
The OR is a relatively noisy work environment.[164]
[165]
[327]
[328]
[329]
[330]
[331]
[332]
[333]
[334]
Mean sound levels are considerably higher than in most offices or control rooms
(continuous air movement through an open surgical suction tip is a common source
of continuous noise), and peak sound levels can be quite high. Some sources of noise
are uncontrollable, such as surgical drills, monitor alarms, and inadvertently dropped
instrument pans; other sources are controllable,
such as conversation and music (see later). There is evidence in the general literature
that noise can adversely affect human performance.[335]
[336]
Furthermore, studies by Murthy and colleagues
[337]
demonstrated that volume-accurate replay of
recordings of OR noise significantly interfered with the speech-discrimination ability
of anesthesia residents during laboratory testing. The OR noise also caused a significant
reduction in residents' performance on psychometric tests of mental efficiency and
short-term memory.[338]
The potential interference
of noise with communication among personnel in the OR is particularly worrisome to
those concerned with optimizing teamwork in this complex work environment.
The use of music in the OR is now widespread. Many health-care
professionals believe that music enlivens the work day and can build team cohesiveness
when all team members enjoy the music. A controversial study by two social psychologists,
Allen and Blascovich,[339]
suggested that surgeon-selected
music improved surgeons' performance on a serial subtraction task and reduced their
autonomic reactivity (i.e., "relaxed" them) when compared with control conditions
with experimenter-selected music or no music at all. The methodology of this study
has been criticized.[340]
Anesthesiologists Swamidoss
and co-workers[341]
presented preliminary data from
a study of anesthesiologists' autonomic reactivity and problem-solving performance
using a screen-based anesthesia simulator. They did not find any significant effect
of "least enjoyed" music compared with either "most enjoyed" music or no music at
all on autonomic reactivity or recognition and correction of simulated critical incidents.
In response to Allen and Blascovich, several anesthesiologists
challenged the notion that the surgeon's preference for type or volume of music can
or should override the needs of the other members of the team.[340]
[342]
This issue generated considerable controversy
among surgeons and anesthesiologists. In a reply to some of the letters to the editor
commenting on their study, Allen and Blascovich[343]
stated: "The letters here suggest that not everyone on the surgical team always
appreciates the type of music chosen by the surgeon, and anesthesiologists in particular
appear to prefer silence in surgery. When we asked the surgeons in our study about
this issue, we were told that the environment of surgery does not lend itself to
the democratic process, and music was part of the environment in which they felt
most comfortable."
There is no simple answer to the question of the proper role of
music in the OR. Clearly, optimal patient care is the primary goal. Some surgical
and anesthesia personnel explicitly forbid any type of music in the OR. A more common
approach of many OR teams is to allow any team member to veto the choice or volume
of music if they believe that it interferes with their work.
