





























the use of cognitiVe task analysis to iMProVe 
anestheia skills training for PostoPeratiVe 
eXtubation

Kären K Embrey CRNA, Ed.D 
Assistant Professor of Clinical Anesthesiology; Assistant Director 
for Clinical Services, Program of Nurse Anesthesia, Keck School 
of Medicine, University of Southern California, Los Angeles, CA.
Kenneth Yates Ed.D
Associate Professor of Clinical Education; Director for Program 
Evaluation, Rossier School of Education, University of Southern 
California, Los Angeles, CA.

Keywords: Cognitive task analysis, extubation training, expertise 
and anesthesiology 

AbstrAct

This study examines knowledge gains in 25 nurse anesthesia 
trainees, following the implementation of a novel instructional 
design, which incorporated cognitive task analysis (CTA) to 
teach an adult postoperative extubation procedure. CTA is a 
knowledge elicitation technique employed for acquiring expertise 
from domain specialists to support the effective instruction of 
novices. Instruction guided through CTA is effective in improving 
surgical skills training for medical students and surgical resi-
dents. The standard, current method of teaching clinical skills to 
novices in nurse anesthesia practice relies on recall-based instruc-
tion from domain experts. However, this method is limited by 
the constraints of expertise, including automation of procedural 
knowledge by the expert practitioner. Automated knowledge 
escapes conscious awareness and access, thus impeding clear 
explication of comprehensive essentials for task execution during 
instruction. CTA guided instruction has been shown to maxi-
mize conceptual, declarative and procedural knowledge gains in 

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novice practitioners by clearly explicating the essentials employed 
when experts execute tasks. Knowledge gains for the task of 
postoperative extubation in 13 junior and senior nurse anes-
thesia trainees were compared to those of 12 trainees, receiving 
standard instruction. The study results indicate that CTA-based 
instruction has a positive and significant effect on procedural 
knowledge gains in the novice anesthetist.

      video: cognitive Task Analysis 

IntroductIon

“There are things that we know but cannot tell. This is strik-
ingly true for our knowledge of skills.”1 Healthcare education 
must incorporate processes to ensure optimal patient outcomes 
as well as best practices for trainee education.2 This is especially 
important for complex cognitive tasks or skills such as postop-
erative tracheal extubation. This task is strategically performed 
to facilitate resumption of respiration, via the normal anatom-
ical airway once mechanical assistance or an artificial airway is 
unnecessary for effective postoperative patient ventilation.2 The 
training of novice practitioners for the performance of this crit-
ical skill must include both the conceptual knowledge (what to 
do and why to do it) and procedural knowledge (when and how 
to do it). Skills training however, may present unique pedagogical 
challenges to the expert charged with educating novices, owing 
to the limitations of automated or implicit knowledge which is 
not readily accessible or shared by expert practitioners.3 Seminal 
research in the acquisition and development of expertise suggests 
that the development of expertise occurs roughly over 10,000 
hours of deliberate practice in a specific domain, where perfor-
mance feedback and improvement are continuous.4,5 However 
over time, knowledge in the expert practitioner becomes uncon-
scious or implicit and automated.6 Moreover, research in educa-
tional psychology suggests that experts routinely omit up to 70% 
of essential information for task execution when they rely on 



recall during clinical instruction.7,8,9  Such omissions in clinical 
instruction may be counteracted by the use of cognitive task 
analysis (CTA) methods. Cognitive task analyses are methods 
used to elicit the full spectrum of expertise necessary for complex 
skill execution in order to improve instructional design for the 
teaching of these skills. In the training of novice anesthesia prac-
titioners, the standard current method of teaching clinical skills 
such as postoperative extubation relies heavily on recall-based 
instruction from domain experts, either in the operating room, 
during case management, or in the simulation laboratory. 

Complex cognitive tasks such as those necessary in the perfor-
mance of postoperative extubation integrate both controlled, 
conscious (conceptual) and unconscious or automated (proce-
dural) knowledge. This knowledge must be strategically executed 
to achieve optimal task outcomes during task execution.10 While 
experts may perform complex tasks and execute procedures with 
exceptional ease and efficacy, they often omit the details of just 
how they perform these tasks because they don’t consciously 
access or share automated aspects of the task. Advances in 
cognitive science however may offer a solution to the problem 
of procedural and declarative knowledge transfer from experts 
to novices, through the application of CTA methods. Cognitive 
task analysis is a systematic approach for capturing the full spec-
trum of knowledge that experts employ during the execution of 
complex tasks. This method of expertise elicitation explicates 
both the observable actions and the cognitive processes (deci-
sions, judgments, and analyses) experts use to solve difficult 
problems and perform complex tasks.11 There are five steps to 
conducting CTA.12 First, the knowledge analyst becomes familiar 
with the domain and tasks to be captured. Then, each type of 
knowledge within the task and sub-tasks is identified. In the 
third step, the analyst conducts a semi-structured interview to 
capture the conceptual knowledge related to the task, as well as 
the action and decision steps the expert uses to perform the task. 
Next, the information collected is analyzed and verified by the 

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expert. Finally, the results are formatted for the intended use, 
such as a protocol for performing the task, job aids, and check-
lists. When CTA is conducted with multiple experts, often the 
70% rule of information omissions can be reversed.13,14 When 
incorporated into training, the application of CTA elicited exper-
tise may offer an improvement over conventional clinical instruc-
tion methods that primarily rely on expert recall,9 by delineating 
task rules and formulating highly accurate and exhaustive algo-
rithmic descriptions of challenging cognitive tasks.15 The appli-
cation of CTA techniques has proven successful in improving 
learner outcomes in medical and surgical skills training16,9 as well 
as improving direct patient outcomes following surgical skills 
training.17 

The purpose of the current study was to determine if CTA 
based instruction of postoperative tracheal extubation is more 
effective than conventional clinical instruction provided to anes-
thesia trainees, as measured by conceptual and procedural pre 
and posttests aimed at assessing both explicit (conscious) and 
implicit (unconscious) knowledge. The study compared the 
comprehensive knowledge gains of students receiving postopera-
tive extubation training following either standard recall-based 
instruction or an experimental instructional design using a CTA 
technique. The following questions were explored:

1. Do participants in the experimental group demonstrate greater 
conceptual knowledge (what to do and why to do it) on post-
operative tracheal extubation than participants in the control 
group? 

2. Do participants in the experimental group demonstrate greater 
procedural knowledge (when and how to do it) in performing 
postoperative tracheal extubation than participants in the 
control group?  

The second question further examined measures on task accu-
racy, timing for task completion and the correct sequencing 



of subtasks within the main task of postoperative tracheal 
extubation.

mAterIALs And metHod

This randomized experimental study employed a design based 
on content captured by the use of a cognitive task analysis to 
elicit knowledge from anesthesia experts for the task of adult, 
awake postoperative extubation. The CTA elicited expertise was 
then used to develop the experimental instructional curriculum 
and the assessment tool used in the quantitative assessments 
of instructional outcomes. The CTA procedure for knowl-
edge elicitation followed the five steps outlined in Clark et al 15 
Three anesthesia experts were individually interviewed to elicit 
knowledge about the action and decision steps, indications and 
contraindications, standards, and equipment for the awake 
adult postoperative tracheal extubation task. The experts were 
also asked about how to manage difficult or unexpected occur-
rences during extubation as well as the conditions under which 
they would defer extubation. Additional information regarding 
other sensory cues and input during task and subtask execution 
was also gathered and included sounds, smells, and tactile input 
surrounding task execution. During a verification process, the 
interviewees subsequently reviewed and clarified the coded data 
obtained in the interviews and represented by a written protocol 
for performing the procedure. Individual protocols from the 
three experts were then aggregated to generate a “gold standard” 
protocol for extubation that was reviewed by three other anes-
thesia experts. The resulting cumulative data were employed to 
generate the instructional protocol and assessment materials, 
including an algorithmic instructional outline explicating exhaus-
tive IF…THEN scenarios which could arise during awake adult 
postoperative extubation and a checklist for evaluating the post 
instructional performances of trainees.  

Following institutional review board approval and informed 

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consent, 25 student registered nurse anesthetist volunteers were 
randomized to stratified control or experimental instructional 
groups. The volunteers included 14 junior students (novices) in 
their first semester of training, who had not previously performed 
tracheal extubation, and 11 senior students (intermediates), who 
had each previously performed roughly 100 supervised extuba-
tions. The experimental group of students (7 juniors, 6 seniors) 
received instruction employing the CTA guided curriculum, 
during a demonstrated task execution, while the control group 
(7 juniors, 5 seniors) received conventional recall-based instruc-
tion during a demonstrated task execution. Except for the 
CTA-derived content for the experimental group training, the 
instructional design, development, and implementation were 
identical for both groups. 

Instruction on tracheal extubation for both the experimental 
and control groups was conducted in a state-of-the-art, high 
fidelity, simulation laboratory using the METIman® (CAE 
Healthcare) human patient simulator, which reacts to inter-
ventions in real time with dynamic and nuanced, high fidelity 
human physiological responses. Experimental participants 
were instructed using the CTA guided curriculum generated 
in the pre-study period. Instruction was delivered during a 
simulated patient extubation with the instructor following 
the CTA generated protocol. Controls received the standard 
recall-based instruction for postoperative tracheal extubation, 
which included standard recall-based instruction on the task 
during a simulated patient extubation. Instruction and evalua-
tions of both the control and experimental groups of trainees 
were videotaped for analysis and data coding. Task instructors, 
both senior faculty members, shared similar experience with 
clinical instruction in the domain of nurse anesthesia practice 
and had similar expertise in the use of the simulation laboratory. 
Both instructors employed a think aloud method of commu-
nication during instruction. All study participants underwent 
uniform pre-briefing and debriefing sessions in keeping with the 



simulation center’s policies for lab participation and training 
and testing content confidentiality. Students’ declarative knowl-
edge was assessed both before and after the training intervention 
via written exam. Both the pre and posttest incorporated a case 
based patient scenario for adult, awake extubation and included 
questions such as the following to assess declarative knowledge: 
1) Name 6 pieces of equipment necessary for safe postoperative 
extubation, 2) What are 4 indications that your patient is venti-
lating effectively on her own once the ventilator has been turned 
off, 3) Put the following 6 subtasks into the correct order for the 
safest postoperative extubation: a) suction the oropharynx, b) 
remove the patient’s protective eye tape, c) take the patient off of 
the ventilator to evaluate how well she is able to breathe on her 
own, d) reverse the neuromuscular blocking agent, e) evaluate 
the train of four response, f) place an oral airway. A total of 
10 such questions were included on the written pre and post-
test. Procedural knowledge was assessed by 2 trained observers 
using the CTA based checklist during participant task execu-
tion in the simulation laboratory following instruction though 
conventional or experimental method. The checklist was used to 
assess the execution of the extubation sequence and the subtasks 
within the 4 delineated temporal categories as seen below in 
Figure 1. The checklist developed for this purpose was the 
simplest outline of the necessary steps for a safe extubation. The 
exhaustive algorithm for extubation which was developed from 
the CTA interviews with anesthesia experts could be used to 
generate expanded content and checklists for future task training 
by evaluating any number of IF…THEN situations that might 
arise during an extubation sequence. More advanced checklists 
could be used to assess additional conceptual knowledge or 
strategic decision making during the process of extubation such 
as in the management of deep extubation or extubation for the 
patient with suspected airway edema. The simple extubation 
sequence checklist used for this experiment included content 
reflecting decision making strategies such as: IF the surgeons have 
completed the surgery but the train of four monitor indicates that 

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the patient has 0/4 twitches THEN begin tapering the inhalation 
agent but keep the patient asleep until the train of four monitor 
indicates neuromuscular blocking agents can be antagonized. The 
temporal categories for the subtasks of the simplified checklist 
for postoperative awake extubation included 1) begin tapering 
anesthetics in response to cues from surgeons, 2) position 
patient for safe emergence and extubation (ensure patient is not 
in Trendelenberg, lithotomy or other unfavorable position), 3) 
emerge the patient and extubate the trachea, and 4) monitor and 
confirm post extubation respiratory homeostasis. The students’ 
performances were assessed by 2 trained observers to evaluate 
whether they did or did not perform each of the subtasks in 
these temporal categories, and whether their performances were 
executed correctly or not. For transparency of decision making, 
student participants employed a think aloud method of commu-
nication during task execution. 

figure1. procedural checklist for Adult, Awake postoperative extubation 

Temporal Frame and Sub Task for Adult Awake 
Extubation  

Circle if not 
done (ND)
Or if done 
incorrectly            
(DI)

Place 
check 
mark if 
done 
correctly

Comments

1. Begins tapering anesthesia in response to cues from 
surgeons

a) Checks train of four response
b) Administers neuromuscular block reversal
c) Suctions oropharynx
d) Monitors for spontaneous ventilation 

ND       DI
ND       DI
ND       DI
ND       DI

2. Positions patient for safe emergence; extubation
a) Employs universal precautions
b) Places oral airway
c) Returns patient to head of bed; supine
d) Ensures patient is safely restrained
e) Removes eye tape
f) Turns O

2 to 100%
g) Monitors alveolar concentration of gases

ND       DI
ND       DI
ND       DI
ND       DI
ND       DI
ND       DI
ND       DI



3. Emerges the patient and extubates the trachea
a) Assesses the patient for emergence; 

observes for return of reflexes 
b) Does not extubate when patient remains 

in Stage II
c) Check respiratory rate is 8- 30/ min, 

checks tidal volume (TV) is appropriate 
(5cc/kg); ETCO2 < 45cmH2O

d) Assists ventilation by hand when 
spontaneous ventilation is inadequate 

e) Reassesses respiratory status for rate and 
minute ventilation. Rate 8- 30/min, TV 
appropriate &ETCO2 < 45cmH2O

f) Looks for regularity of respiratory rate
g) Confirms patient is in Stage I using 

specific criteria (such as eye opening, 
hand squeeze, head lift, tongue 
projection) 

h) Places circuit mask, syringe & suction in 
appropriate reach

i) Loosens tape on face
j) Deflates endotracheal tube (ETT) cuff 
k) Increases positive pressure ventilation; 

squeezes bag or sets APL valve to 
20cmH2O pressure and removes ETT 
from trachea 

ND       DI

ND       DI

ND       DI

ND       DI

ND       DI

ND       DI
ND       DI

ND       DI

ND       DI
ND       DI
ND       DI

4.  Monitor and confirm post extubation respiratory 
homeostasis

a) Immediately following extubation places 
the circuit mask on the patient’s face and 
confirms CO2/ mist (pt is free of obstruction)

b) If not, repositions the mask / checks for 
breath holding/ provides chin lift

c) If obstruction is suspected places OA(uses 
tongue blade or NA as needed)

d) Suctions again post extubation if needed
e) Confirms respiratory homeostasis & places pt 

on transport mask at > 6LPM
f) Raises the head of the bed, keeps O2  

saturation monitor in place until leaving the 
OR

g) Monitors patient during transport to PACU – 
watches for mist in the mask/ chest rise/ skin 
color and listen for obstruction 

ND       DI

ND       DI

ND       DI

ND       DI
ND       DI

ND       DI

ND       DI

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Figure 2 below shows the timeline for the study which was 
conducted over two days. 

figure 2. Study flow and Timeline 

 

resuLts

The purpose of this study was to determine if CTA based 
instruction of postoperative tracheal extubation is more effective 
than conventional clinical instruction by domain expert provided 
to anesthesia trainees, as measured by conceptual and procedural 
pre and posttests. For all statistical analyses in this study a 95% 
confidence level (p < 0.05) was employed. Using independent 
t-tests, comparisons were made of the differences between the 
control and experimental groups’ performances for both declara-
tive and procedural knowledge. The study also evaluated the 
expected and observed performances of students in both control 
and experimental groups who had prior experience performing 
extubation and compared these to those of students without 
prior experience performing the task. To examine effects of 
prior knowledge on procedural performance for correct subtask 
sequencing, X2  values were calculated using the raw data from 
the assessments of the experimental senior and junior students 

   0700        0720-0735    0735-0800       0800 – 0825        0830-1045        1045-1115    1115-1130



and the control senior and junior students. These X2 values were 
then tested for significance.

Question 1: Do participants in the experimental group demon-
strate greater conceptual knowledge (what to do and why) on 
postoperative tracheal extubation than participants in the control 
group? In the assessment of declarative knowledge, an indepen-
dent samples t-test demonstrated no significant differences in 
baseline or post intervention declarative knowledge on extuba-
tion between the control and experimental groups: t (23) = -.843 
(p= .408), thus demonstrating equivalence in conceptual knowl-
edge prior to the training, and no significant gain by the experi-
mental group on conceptual knowledge during the training.

Question 2: Do participants in the experimental group demon-
strate greater procedural knowledge (when and how to do it) in 
performing postoperative tracheal extubation than participants 
in the control group? For this question, task accuracy represented 
the measure of procedural knowledge. Findings demonstrated 
a significant difference for juniors who received CTA guided 
instruction (70.46 ±12.43), compared to the control group of 
juniors (60.71 ± 6.99) (p =.047) who received standard recall-
based instruction. There was also a trend toward improvement in 
task accuracy in the experimental senior students’ performances 
compared to control senior performances, though this was not a 
statistically significant finding. 

The second research question further examined measures on 
task expediency by examining the time required to complete the 
task, and the correct sequencing of subtasks within the main task 
of postoperative tracheal extubation. Subtasks included measures 
such as suctioning the oropharynx, antagonizing the neuromus-
cular blocking agents and assessing for adequate patient venti-
lation. For task expediency, a significant level of expediency 
was found (8.83 minutes ± 1.33) for the experimental group of 
seniors and juniors when compared to their control counterparts 

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(10.75 minutes ± 2.34) (p = .022).  Juniors in the experimental 
group outperformed control juniors; (9.00 minutes ± 1.291) 
versus (11.43 minutes ± 2.637) (p = .049) in task expediency.  

A comparison between the performances of all junior and all 
senior students in the study for the execution of correct subtask 
sequencing of the extubation skill set was performed. The find-
ings were significant X2 (1, N = 25) = 8.766, p = .003, and not 
unexpected as all senior students had performed roughly 100 
extubations before the study. However, the difference in expected 
and observed performance was particularly statistically signifi-
cant for the senior experimental students (X2 = 6.198, p = .013). 
These results may demonstrate that CTA guided instruction is 
effective in improving procedural knowledge gains even in the 
learner with higher levels of prior experience, in whom the task 
may already be automated to some extent. Under conditions of 
prior experience and task automation, instructors face the chal-
lenge of students with prior beliefs and methods which must be 
“unlearned” to facilitate effective instruction. The CTA guided 
instructional format appeared to effectively meet this challenge.  

In summary, junior students, task novices demonstrated signifi-
cant improvements on task accuracy as well as task expediency 
following CTA guided instruction on adult, awake postoperative 
tracheal extubation. These findings support the benefits of CTA 
guided instruction for novice practitioners. Interestingly, more 
experienced seniors in the experimental group also demonstrated 
a trend toward improvements in task accuracy and expediency 
when compared to control group seniors. Experimental senior 
students also demonstrated statistically significant improvements 
in correct sequencing for the subtasks of extubation, despite the 
burden of their prior knowledge which had to be unlearned. This 
important finding may demonstrate the added benefit of CTA 
guided instruction for students or practitioners with higher levels 
of prior knowledge, in whom it can be assumed, task automation 
is already established to some degree. 



Table 1: Percent Task Accuracy Following Instruction 

Table 2: Task Expediency Following Instruction

Table3: Correct Subtask Sequencing Following Instruction 

dIscussIon

The purpose of this study was to examine the effectiveness 
of CTA guided instruction compared to conventional recall-
based clinical instruction delivered to student registered nurse 
anesthetists for adult, awake postoperative tracheal extuba-
tion. The standard, current method of teaching clinical skills in 
the operating room or simulation lab to novices in medical and 
nursing specialties, including anesthesiology, relies on recall-
based instruction from domain experts. Instruction by experts 
however is limited by task automation on the part of the expert 
practitioner. Automated or unconscious knowledge is not readily 
accessible to the expert teacher and may inhibit explication of all 
the necessary subtasks and essentials for task execution during 
teaching. Cognitive task analysis or CTA is a comprehensive 
knowledge elicitation technique used for acquiring expertise and 
designing exhaustive protocols from information gained from 
domain specialists which can support the effective instruction 
of novices. The application of CTA guided instruction has been 
demonstrated as successful in improving learner outcomes in 
medical and surgical skills training16,9 as well as improving direct 
patient outcomes following surgical skills training.17 

Findings from the current study demonstrate positive trends 
and statistically significant improvements in the performances of 
student registered nurse anesthetists learning the task of adult, 
awake postoperative tracheal extubation through CTA guided 
instruction in the simulation laboratory, when compared to 
controls receiving conventional recall-based instruction. 

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This is the first known study employing CTA to inform instruc-
tional content for nurse anesthesia task training, and the study’s 
findings are positive and in keeping with other similar studies 
examining surgical skills training for residents and medical 
students. Performance improvements in the anesthesia trainees 
were specifically significant for procedural knowledge gains 
in the areas of task accuracy, task expediency and subtask 
sequencing following CTA-guided instruction. Similar studies 
with larger participant pools may be required to more thor-
oughly evaluate the efficacy of CTA-guided instruction for skill 
acquisition in nurse anesthesia training. 

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