ORIGINAL ARTICLES

Gaze disruptions experienced by the laparoscopic operatingsurgeon

Erica Sutton • Yassar Youssef • Nora Meenaghan •

Carlos Godinez • Yan Xiao • Tommy Lee •

David Dexter • Adrian Park

Received: 4 June 2009 / Accepted: 6 October 2009 / Published online: 24 December 2009

� Springer Science+Business Media, LLC 2009

Abstract

Background Disruptions to surgical workflow have been

correlated with an increase in surgical errors and suboptimal

outcomes in patient safety measures. Yet, our ability to

quantify such threats to patient safety remains inadequate.

Data are needed to gauge how the laparoscopic operating

room work environment, where the visual and motor axes are

no longer aligned, contributes to such disruptions. We used

time motion analysis techniques to measure surgeon atten-

tion during laparoscopic cholecystectomy in order to char-

acterize disruptive events imposed by the work environment

of the OR. In this investigation we identify attention dis-

ruptions as they occur in terms of the operating surgeon’s

gaze. We then quantify such disruptions and also seek to

establish what occasioned them.

Methods Ten laparoscopic cholecystectomy procedures

were recorded with both intra- and extracorporeal cameras.

The views were synchronized to produce a video that was

subsequently analyzed by a single independent observer.

Each time the surgeon’s gaze was diverted from the opera-

tion’s video display, the event was recorded via time-stamp.

The reason for looking away (e.g., instrument exchange),

when discernable, was also recorded and categorized. Dis-

ruptions were then reviewed and analyzed by an interdisci-

plinary team of surgeons and human factors experts.

Results Gaze disruptions were classified into one of four

causal categories: instrument exchange, extracorporeal

work, equipment troubleshooting, and communication. On

average, 40 breaks occurred in operating surgeon attention

per 15 min of operating time. The most frequent reasons

for these disruptions involved instrument exchange (38%)

and downward gaze for extracorporeal work (28%).

Conclusions This study of laparoscopic cholecystectomy

performance reveals a high gaze disruption rate in the current

operating room work environment. Improvements aimed at

reducing such disruptions—and thus potentially surgical

error—should center on better instrument design and

realigning the axis between surgeon’s eye and visual display.

Keywords Gaze � Disruptions � Surgeon � Ergonomics �Laparoscopic cholecystectomy

In the current era of increasingly patient-centered safety

awareness, error reduction strategies are paramount. Dis-

ruptions experienced by operators performing critical tasks

in high-stakes environments interfere with task flow and

degrade performance, at times with disastrous results [1, 2].

Human factors analyses of data from NASA’s Aviation

Safety Reporting System have indicated that disruptions in

E. Sutton � Y. Youssef � N. Meenaghan � D. Dexter � A. Park

Department of Surgery, University of Maryland School

of Medicine, Baltimore, MD, USA

C. Godinez

Department of General Surgery, Naval Air Station Jacksonville

Hospital, Jacksonville, USA

e-mail: Carlos.Godinez@med.navy.mil

Y. Xiao

Baylor Health Care System, Dallas, USA

e-mail: Yan.Xiao@baylorhealth.edu

T. Lee

Department of Surgery, Creighton University Medical Center,

Omaha, USA

e-mail: TommyLee@creighton.edu

A. Park (&)

Division of General Surgery, University of Maryland Medical

Center, 22 S. Greene Street, Rm S4B14, Baltimore,

MD 21201-1595, USA

e-mail: apark@smail.umaryland.edu

123

Surg Endosc (2010) 24:1240–1244

DOI 10.1007/s00464-009-0753-3

high-workload situations are a contributing factor in 86%

of aviation mishaps [3]. The impact of gaze disruption in

terms of surgeons on intraoperative performance is not well

known; however, it is anecdotally evidenced to be

common.

Factors affecting surgical workflow have been little

studied and quantified. For laparoscopic surgery especially,

technology, instrumentation, and techniques evolve rap-

idly, resulting in unique interactions whose effects, and

possibly conflicts, cannot be entirely predicted. Technical

innovations intended to improve performance or even

enhance safety can unwittingly distract operators, a phe-

nomenon that is known to have contributed to aviation

accidents [4]. It is not surprising, therefore, that surgical

workflow disruptions and attention deficits in the operating

room (OR) have been shown to increase errors, resulting in

suboptimal outcomes and threatened patient safety [1, 5].

Several elements inherent to the laparoscopic OR work

environment potentially can distract operators from a sur-

gical task. Visual and motor axes are not aligned, subtly

increasing mental workload for both surgeon and assis-

tants. Image degradation via faulty equipment or simple

contamination of the lens with body fluids or other con-

taminants is a common complaint. Furthermore, for sur-

geons, laparoscopic surgery may be affected by disruptions

that are inherent to the minimally invasive technique itself,

although this is not well characterized. The need for fre-

quent instrument exchanges, trocar and line management,

and necessary support equipment such as gas insufflators

and foot pedals contribute to disruptions in attention for the

surgeon, a human operator with a finite capacity for task

management.

During performance of operative procedures, selective

attention—the ability to focus on what’s important while

disregarding what’s not—is crucial. Attention span is the

interval an individual is able to concentrate on a single

object, idea, or activity. The general human attention span

is short. For example, adult education research reveals that

adult learners can remain attentive to a lecture for no more

than 15-20 min at a time and that attentiveness becomes

ever shorter, often averaging a mere 3 or 4 min, as the

lecture continues [6].

In this investigation we sought to quantify gaze dis-

ruption experienced by operating surgeons in order to

determine the real-time dynamics of surgical flow disrup-

tions and their potential impact on surgical performance.

For the purposes of this study, we defined such a disruption

as a break in the primary surgeon’s gaze at the liquid

crystal display (LCD) monitor during the performance of

laparoscopic cholecystectomy (LC). It is recognized that it

is ergonomically beneficial to occasionally divert one’s

gaze from the monitor to prevent eye fatigue. Therefore,

we further sought to identify the factors that occasioned

gaze diversions. We hypothesized that data on such dis-

ruptions during laparoscopic operations could be prospec-

tively collected, quantified, and analyzed as a first step

toward developing effective strategies to minimize any

adverse impact that gaze alterations might cause in regard

to laparoscopic surgeons.

Methods

Under an Institutional Review Board-approved protocol,

multichannel video data were prospectively collected on

ten nonconsecutive LC cases performed or supervised by a

single experienced surgeon (AP) and a dedicated mini-

mally invasive surgery (MIS) team. Indication for opera-

tion was for symptomatic cholelithiasis for all cases. LC

was considered particularly suited to the purposes of this

study because it is commonly performed and requires

multiple instrument exchanges, cautery, suction, at least

one assistant, and other elements common to laparoscopic

procedures. An attention disruption was defined as a break

in the surgeon’s visual gaze from the LCD monitor to any

other region of the operating theatre. Case time was defined

from the time the laparoscope was introduced within the

abdomen until the final removal of the scope just prior to

trocar site closure. A signed consent form was obtained

from each operating team member, including the surgeon,

assistants, and the OR nursing personnel.

A digital recording system was established with three

separate but synchronized feeds: (1) a wide-lens camera

mounted on top of the operating surgeon’s primary monitor

(similar to a webcam-type setup) to record a video over-

view of all the actions performed by the team, (2) laparo-

scopic video input that recorded the intra-abdominal

portion of the operation, and (3) a single audio feed cap-

tured by a wireless microphone worn by the operating

surgeon (AP).

Synchronized data capture from all three feeds was

recorded by a multichannel digital video recorder (DVR).

Video and sound data from all cases were buffered in

Audio Video Interleave (AVI) format on DVR. Targeted

cases were then extracted from the DVR within 24 h of

buffering and stored securely in MPEG format. Synchro-

nized audio and video analysis was made possible by use of

a propriety software program, which enabled event anno-

tations and time-stamped data. All inputs could then be

monitored and annotated by a single analyst from a single

computer screen image (Fig. 1).

Synchronized audio data as well as video obtained from

both the wide-lens exterior camera and the laparoscope

were reviewed by a surgical resident and/or fellow who

was not a member of the operative team. A note was

recorded each time the operating surgeon looked away

Surg Endosc (2010) 24:1240–1244 1241

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from the LCD monitor and each time he resumed looking

at the monitor. For each episode of gaze disruption, an

attempt was made to place the reason generating it into one

of the following categories: instrument exchange, need to

work extracorporeally, need to adjust or clean instruments,

need to orient to cautery foot pedal, or need to communi-

cate with other team members. Instruments analyzed for

exchange and movement included the dissector/grasper,

camera, clip applier, suction/irrigator, laparoscopic scissor,

and cautery hook. The accuracy of coding methods was

verified by a human factors specialist and an occupational

epidemiologist.

Results

Ten nonconsecutive LC procedures were recorded and

analyzed. Total case time that was studied was 551 min

with an average case time of 55 min. There were, on

average, 40 breaks in surgeon gaze per 15 min of operating

time or 147 disruptions per case. The most common rea-

sons for disruptions involved instrument exchange (38%)

and downward gaze for extracorporeal work (28%).

Because manipulation of the ports, camera, and foot pedal

all pertained to OR equipment, they were combined under

a single category ‘‘equipment troubleshooting’’ (16%).

Communication (8%)—defined as talking done by the

surgeon with any other operative team member—also

resulted in gaze breaks.

Throughout the ten cases, 1471 instrument movements

occurred, an average of 158 movements per case. The most

common instrument exchanges occurred between the dis-

sector/grasper and the clip applier, between the clip applier

and the laparoscopic scissors, and between the dissector/

grasper and the cautery hook (Table 1).

Discussion

Our study used LC, a relatively common and modestly

complex procedure, as a means by which gaze interruptions

between the surgeon and patient interface may be quanti-

fied and characterized. Human factors experts have made

the distinction that interruptions to a task may often be

characterized as disruptions, meaning that either increased

time is necessary or cognitive cost is exacted before

resumption of the interrupted task [7]. A change in gaze is

an interruption to task performance. Given the fact that

disruptions to surgical workflow have been correlated with

Fig. 1 A single computer

screen image allowed an analyst

to monitor and annotate inputs.

Synchronized data capture from

all three feeds was recorded by a

multichannel digital video

recorder (DVR)

Table 1 Table of events

Instrument exchange (3 most common)

Dissector/grasper $ clip applier

Clip applier $ laparoscopic scissors

Dissector/grasper $ cautery hook

Extracorporeal work

Port placement

Instrument orientation

Gallbladder extraction

Fascial closure

Equipment troubleshooting/manipulation of camera, ports, or foot

pedal

Cleaning the camera

Orienting to the foot pedal

Communication

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123

an increase in surgical errors [2], our finding of just under

three interruptions per minute of operating time in the case

of LC performance is alarming.

Studies have examined surgical flow disruptions using

time motion analysis. They warrant comparison with our

study of surgeon-specific gaze breaks in the OR.

Wiegmann et al. [2] reported an average of 8.1 surgical

flow disruptions per hour of operating time over 31 cardiac

surgical procedures. This would seem to be far fewer than

our estimate of 160 attention breaks per hour of operating

time. Yet, several important differences exist. In Wieg-

mann’s study, a surgical flow disruption was defined as ‘‘a

deviation from the natural progression of an operation,

thereby potentially compromising the safety of the opera-

tion.’’ Gaze disruption as we have defined and used the

term does not necessarily constitute a deviation from the

natural progression of the operation. Certainly, the act of a

surgeon looking away in order to exchange an instrument

must be considered one of many actions that constitute the

natural progression or steps involved in performing LC [8].

As a consequence, the data observed in our study inevitably

result in a far greater number of events. In addition, We-

igmann’s study pertains to an open, not laparoscopic, sur-

gical procedure. The well-described unique and increased

demands posed by the MIS approach [9–11] could also

account for our study’s higher event rate.

A study by Healey et al. [12] provides further input into

disruptions within the OR environment. They reported that

in over 50 operations, including both open and laparo-

scopic procedures, 1.04 ± 0.07 interfering events occurred

per minute of operating time (range = 0.22–3.04 events/

min). Their data were not surgeon-centered but rather

counted interruptions (e.g., pager beeping, door opening)

affecting the entire operating team. Healy’s study suggests

that under current OR working conditions, interruptions are

high which supports our concluding estimate of 2.65

attention breaks per minute.

Given that for every minute of operating time the surgeon

could experience two to three breaks in attention, we iden-

tified four categories explaining these interruptions: instru-

ment exchange (38%), extracorporeal work (28%),

equipment troubleshooting (16%), and communication

(8%). Our findings are in agreement with the categorization

and frequency of OR disruptions recently published by

Sevdalis et al. [13] and very closely mirror those of Geryane

et al. [14]. Geryane et al. applied time motion analysis

techniques to LC and presented findings as a percentage of

total OR time. The authors found the following in regard to

operating time: 17% was devoted to instrument exchange,

26% was spent on extracorporeal work, and 13% was spent

troubleshooting equipment. Again, despite the use of dif-

ferent measures, we found similar factors and frequencies in

regard to disruptions affecting the surgeon and the operation.

Using our quantitative estimate of the frequency with

which the interface between surgeon and primary task are

interrupted, we refer to human factors literature to identify

ways to reduce gaze disruptions or improve adherence to

the primary task. Ratwani et al. [7] have studied the effect

of interruption modality on primary task resumption. Their

work demonstrates that the fastest resumption of the pri-

mary task occurs when the primary task interface remains

available during the interruption. Their finding supports the

concept that looking away from the laparoscopic monitor

to exchange an instrument is more disruptive than, for

example, the verbal instruction given to residents or nurs-

ing staff while operating. It should be acknowledged that

some breaks in gaze are not merely interruptive but serve

the purpose of giving the surgeon’s eyes a break from the

display, thus reducing eye strain and fatigue. The optimum

interruption of gaze must lie somewhere between that

which is needed for visual comfort and the 2.65 breaks per

minute observed in our study.

Reaching the optimum number of gaze breaks could be

achieved by improvements in several aspects of the sur-

gical environment. Multipurpose instruments and ergo-

nomically favorable screen placement could result in more

strictly maintaining surgeon adherence to primary tasks.

Technological and design innovations in multipurpose

instruments have been attempted as a solution in the past.

Efforts fell short of improving surgeon attention because

the combined instruments did not perform any function as

well as the individual counterparts. Indeed, combining a

dissector with a clip applier or laparoscopic scissors may

not offer the surgeon an improvement in function and could

risk an unwieldy or less safe instrument. Given that,

however, instrument design should still be revisited as a

means to improve surgical workflow. The development of

‘‘smart instruments’’ capable of sensing proximity to other

instruments and aiding in collision avoidance would

improve workflow and surgeon attention to primary task. In

addition, ‘‘Smartimage’’ and heads-up display technology

would allow for apposition of radiographic and clinical

data to the laparoscopic view, reducing the need to divert

one’s gaze for the purpose of reviewing images or trou-

bleshooting equipment. Cuschieri and coworkers [14, 15]

have performed extensive studies into the benefits,

including resultant improvements in workflow, of a gaze-

down visual display in relation to the physical and cogni-

tive workload required of surgeons. Innovations of tech-

nological, display, and imaging systems could result from

further study of surgeon-specific gaze disruptions and the

optimum workflow needed in the surgical environment.

We acknowledge certain limitations to this study. While

we were able to obtain very accurate counts of our gaze-

defined attention disruptions, we used only a single

observer for each case and then made inferences as to why

Surg Endosc (2010) 24:1240–1244 1243

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the surgeon had looked away from the monitor based on

what was occurring in each viewed video. It is conceivable

that inaccurate assumptions made by our observer could

have gone unchallenged and that any potential bias as to

the reason for interruption could have been carried

throughout all ten cases.

Furthermore, having made every effort to identify the

extent to which a gaze break is disruptive based on human

factors literature, we did not employ subjective ratings or

objective measurements of cognitive workload. Thus, we

are unable to describe the exact relationship between a

break in the surgeon’s visual attention from the laparo-

scopic screen and what, if any, welcome or unwelcome

effects were associated with that break in attention or with

task resumption. The test conditions needed to introduce

and study detrimental effects on attention are clearly best

tested in controlled laboratory settings. The safety and

reliability of introducing such equipment or live techniques

into the operational environment is at best uncertain. In

addition, studies that have used an ordinal ranking of OR

disruptions have done so retrospectively and are subject to

their own biases as a result [12, 13].

Conclusion

In the current operative environment, and in the specific

case of LC, we identified a high rate of gaze interruptions

in relation to the surgeon’s attention to the primary task.

Improvements aimed at reducing such interruptions—and

thus potentially surgical error—should center on realigning

the axis between the surgeon’s eye and visual display.

Future studies involving surgeon-specific attention inter-

ruptions are needed. Such research might examine differ-

ences in disruptions noted between attendants or residents

in the role of primary surgeon or use a quantifying scale by

which to determine the positive or negative impact asso-

ciated with interruptions in the surgeon’s visual gaze.

Disclosures Drs. Erica Sutton, Yassar Youssef, Nora Meenaghan,

Carlos Godinez, Yan Xiao, Tommy Lee, David Dexter, and Adrian

Park have no conflict of interest or financial ties to disclose.

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