11 Training Adults to PerformCardiopulmonary Resuscitation

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From: Contemporary Cardiology: Cardiopulmonary Resuscitation Edited by: J. P. Ornato and M. A. Peberdy © Humana Press Inc., Totowa, NJ

11 Training Adults to Perform

Cardiopulmonary Resuscitation

What Works?

Barbara Riegel, ^DNSC , ^RN , ^CS , ^FAAN ,

Lars Wik, ^MD , and Alidene Doherty, ^RN , ^BSN

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INTRODUCTION

Cardiopulmonary resuscitation (CPR) is first-line therapy for sudden, unexpected, cardiac arrest (CA). Laypersons are most likely to administer CPR because most CAs occur in the home or in the community. Training laypersons to adminster CPR has become a routine activity but some would argue that it is not an activity that we do particularly well. Out-of-hospital resuscitation attempts have led to very low survival rates (1–13)—less than 10% survival in Europe (2,3,6–8) and the majority of urban areas in the United States (1,9–13). Densely populated urban areas such as Chicago and New York City have a particularly low rate of sudden CA survival (13) as do rural areas.

One reason for the universally low survival rates is that the frequency of CPR initiation by bystanders remains extremely low (10,12–17). Initiation of resuscitation by bystand- ers clearly increases survival (1,6,17–19) but the rate of basic life support (BLS) initiation by bystanders in the United States is typically less than 30% (9–16) and rarely greater than 50% in Europe (6,8,17).

Our ultimate challenge is to increase the number of bystanders initiating CPR. How

to manage this is not known for certain, but it is the thesis of these authors that low rates

of CPR are a direct consequence of our ineffective teaching methods. Much is known about how to teach adults and traditional approaches violate most principles of adult learning. Perhaps current approaches to CPR training should be largely abandoned in favor of new methods. Many of the nationally recognized CPR training organizations have modified their programs to emphasize student practice time and minimize instructor lecture, a tactic consistent with adult learning principles. However, other, more radical methods should be considered. In this chapter we discuss approaches to training adults in CPR that work.

HOW DO ADULTS LEARN BEST?

Maximizing the acquisition of BLS knowledge and skills requires changing the tradi- tional teaching model from instructor-to student-centered. Knowles (20) is usually cred- ited with being the first to suggest that adults learn in a manner that is different from that of children. However, others such as Rogers (21), have been influential in helping us to understand that adults learn when the information is relevant, practical, and tied to exist- ing knowledge. Adults must feel respected and free to direct their own learning if they are to acquire new knowledge. Adults are typically busy so learning situations that are fun and directed by someone who is likeable and worthy of respect facilitates learning.

Barriers to learning such as lack of time, money, and transportation must be minimized if adults are to participate in learning events. These principles are described more fully later along with practical examples of ways to address them in CPR training.

RELEVANCE

Adults learn best when they see the relevance of what they are learning. Scenario- based instruction has been recommended as a method of making CPR training relevant, practical, and useful. Scenario-based instruction involves modifying the story surround- ing each simulated event to fit the student’s individual situation. In this way, the instructor maximizes relevance and allows the student to practice the CA scenario most like what he or she will experience. Modification of the scenario allows the student to think through an actual situation and build on existing knowledge. Scenario-based instruction is par- ticularly helpful for students who learn primarily through observation.

Scenario modification is most effective when it is consistent with the experience of the student. For example, if training police officers who will be responding after a call to 911, it makes little sense to ask them to notify 911. However, if the scenario is modified to have the officer update the dispatcher with information, it becomes consistent with the routine practice of the officer. It is helpful if the scenario can be made as realistic as possible. For example, continuing the police officer example, using a model phone or one that is not plugged in instead of just pretending to call 911 would make the scenario more realistic (22). Current thinking is that the “pretend” or acting surrounding many of the steps in CPR training interfere with skill demonstration and perhaps with skill learning itself.

Only common, clinically relevant situations should be included in scenarios. For

example, it has been shown that when an instructor ends a class by practicing an uncon-

scious obstructed airway scenario, students tend to confuse chest compressions and

abdominal thrusts (23). Additionally, if each scenario results in a return of spontaneous

circulation, the student leaves the classroom with the unrealistic expectation that all CA

victims will recover.

An important element influencing perceived relevance is the message that the learner receives regarding importance of the training. In one study testing the effectiveness of CPR training by videotape, about half of the 8659 recipients of the videotape did not even view it although the tape was sent to homes of patients at risk for sudden cardiac death (24). An equal number of CAs occurred in each group, but the bystander CPR rates did not differ (47% video vs 53% controls), nor did hospital discharge rates (n = 3 vs n = 2).

Clearly, the video recipients were not convinced that the tape would be relevant for them.

POSITIVE REGARD FOR THE INSTRUCTOR

Positive regard for the instructor facilitates learning. In 1991, Kaye (25) published a paper titled “The Problem of Poor Retention of Cardiopulmonary Resuscitation Skills May Lie With the Instructor, Not the Learner or the Curriculum,” making this point.

Others (26) have found that CPR instructors had limited knowledge of the courses they taught, did not understand or follow recommended teaching practices, did not read their instructor manuals, and could not even pass a CPR provider test. If this is the case, it is not surprising that one author (27) found that 10% of instructors were considered by students to be incompetent, 9% of the students stated they would not perform CPR after the course, and 23% stated mistakenly that they could be legally prosecuted if they did CPR on a stranger.

Most of the information that CPR instructors teach and the style used to teach it has been passed down by tradition. Instructors typically model an instructor they admired.

Few have heard how their words and stories sound to the students. Few realize how they make the students feel, and how their well-intentioned words distract the learners from the important skills that they have come to learn. When instructors provide anecdotes and depart from the script, a decrease in written test scores has been demonstrated (28,29).

For every 2 minutes of anecdote, cognitive scores dropped 1% overall. So, adding just 20 minutes of additional material (anecdotes and stories), as most instructors do, could lower students’ test scores by 10%. Clearly, more emphasis is needed on helping instruc- tors to be better teachers, if the traditional model of instructor-based courses continues.

FREEDOM TO DIRECT ONE’S OWN LEARNING

Another important principle of adult learning is that adults learn best when they are

free to direct their own learning. Several investigators have developed and tested vari-

ous methods of self-learning that maximize individuals’ freedom to direct their own

learning experience. In the 1970s, Berkebile and colleagues (30,31) compared five

training methods in suburban schools in Pittsburgh. A traditional instructor-led CPR

class lasting 3 hours and an untrained control group were compared to (a) self-practice

on recording mannequins, coached by audiotapes and flip charts, (b) repeated (16

times) viewing of a new 10-minute CPR demonstration film over a 3-month period, and

(c) viewing the new 10-minute film plus self-practice on mannequins (32). The record-

ing mannequin and flip charts demonstrating proper technique were available through-

out the study period in the learning laboratory. Knowledge and skill performance at 1

and 12 months were superior in the group who viewed the film and did self-practice

when compared to the traditional instructor-led course. Self-practice alone was supe-

rior to repetitive film viewing alone. Repetitive film viewing alone was superior to no

training. More students passed heart compressions than ventilations. In another study,

Kaye and colleagues (33) demonstrated superior skill performance after interactive computerized self-training compared to those given the traditional instructor-led course.

These studies demonstrate that students free to direct their own learning performed better than those sitting through the traditional, instructor-led course.

An innovative approach to self-learning was developed and tested by Braslow and associates (23,24) called “video self-instruction” or “watch and practice.” Instead of watching a video and then practicing, the “watch and practice” approach was designed to include synchronous practice. That is, viewers practiced and learned along with the videotaped expert demonstration—just like a Jane Fonda exercise video. To increase learning, the video contained no lectures, no information on anatomy and physiology, no rates and ratios, and no complicated methods for locating the compression point and opening the airway—to name a few. Information on heart attack care and airway obstruc- tion was removed. This approach allowed for more than 25 minutes of continuous CPR practice, compared with approx 2.5 minutes of practice in the traditional 4-hour CPR course. When the video self-instruction was compared to the traditional instructor-based course, it worked well, even in persons over age 50, a group that often has lower skill retention than others. Participants learned CPR in only 30 minutes—without an instructor or textbook—and outperformed students who had just completed the traditional course.

The efficacy of self-training has been known since the 1970s (30,31,35–37). Courses by instructors remain the accepted method of training in CPR despite this. Instructors are not the obstacle, but a fixed time available for practice is less effective than unlimited time for self-practice.

OVERCOMING BARRIERS

Common barriers to learning CPR are lack of time and/or transportation. Standard group classes with mannequin training are 3 to 4 hours in length, a significant time commitment for adult learners with other responsibilities. Another barrier is lack of interest in learning a skill one may never use. Additionally, learning style, speed, and physical agility vary widely among adults, which can be a barrier to those concerned that they may not keep up with others in a formal class. Societal cost of training large numbers of laypersons is a major barrier as well.

Motivating the Learner

Individuals who are not interested in learning CPR may be motivated to learn CPR to help others. Research into the psychology of “helping behavior” (what makes some people act when confronted with an emergency, whereas some do not act) tells us that before someone can perform in a CA or other emergency situation, psychologically, they must feel able and ready to do so (38). Yet, most people are not. Historically, this prereq- uisite has been ignored perhaps because CPR and other emergency cardiac care training began as training for physicians and has not been tailored to lay people. Depending on the instructor, some trainees feel badgered by instructors and others feel supported to learn. Self-efficacy, or perceived ability to perform the skill of CPR must become part of the training program if the rate of bystander CPR is to increase (39).

Cost to Society

The societal cost of training is a major obstacle for widespread use of CPR. In order

to lower the cost, Wik et al. (40) introduced peer CPR training based on the belief that

a handful of lay people trained as CPR instructors could train their coworkers, who in turn would train their relatives, and so on. The effect of this approach is similar to a domino effect potentially resulting in a significant increase in the number of skilled CPR provid- ers at a low cost. An inexpensive take-home mannequin together with a flip chart and a 20-minute videotape were used. When those trained using the peer approach were com- pared to those trained with the traditional method, third-generation trainees proved equally effective at CPR as those trained directly with the traditional method.

In an extension of this approach, Wik (40) trained people in CPR and then sent a mannequin and videotape home with them to train their family members on their own.

Training of family members was accomplished in under 60 minutes. How well did they do? The family members’ CPR performance was equal to, or most often better than the performance of students coming out of traditional instructor-based CPR courses. Why?

We believe that peer-to-peer learning and modeling are learning methods with which laypersons feel comfortable. In fact, peer-to-peer learning and modeling reflect a natu- ral and universal method of learning. Throughout life, important learning takes place in the home and this is the environment in which most will use CPR if they ever have to use the skill.

TRANSFERRING LEARNING TO REAL-LIFE EVENTS

CPR acquisition includes both cognitive learning and skill retention. Cognitive learning regarding the correct sequence to perform occurs by seeing (reading or mim- icking) and by hearing. The learner needs to remember the algorithm at the same time as it is performed with quality and speed. No study has shown that lecturing about physiology, medicine, and risk issues—common content in traditional CPR courses—

improves skill performance (25,29,41–43). In fact, lecturing and reading may distract the learner and result in information overload. Braslow (23) found that when the “heart- healthy” information was eliminated from the class, practice time increased and skill improved.

Clarity of the message (i.e., focus on essential information only) is important but controversy continues regarding what to teach the lay public about CPR. Should we teach abdominal thrusts (44) or back blows for suspected foreign body obstruction (45,46)? Is moderate backward tilt of the head plus jaw thrust and separation of the lips (the triple airway maneuver) the best airway control measure for comatose trauma victims (47–49)? How should we position patients in coma with spontaneous breathing (horizontal supine vs stable side position, both with head tilted backward [45])? What should we teach about when the lone rescuer is justified to leave the individual tempo- rarily to call for help?

Pathophysiology must guide instructional content. Complete airway obstruction (as in drowning, brain trauma, intoxication) results in CA within 5 to 10 minutes (50–52). In many situations, complete recovery can be achieved with CPR steps A and B alone (50–

54), which reinforce the teaching of steps A, B, and C together. For normothermic sudden

CA, we know the time limits for preventing permanent damage to the brain (4 minutes

[55–57]) and the heart (20 minutes [57,58]). Therefore, teaching must stress that only

resuscitation initiated within seconds of collapse can provide the necessary oxygen

delivery to maintain viability of the individual until arrival of advanced life support

personnel. Teaching the importance of continuous chest compression and ventilation

with a minimum of pauses (no-flow periods) is essential.

Practice Time

Practice time has been shown to be the most important factor in acquisition of BLS for adult learners (23). Maximizing the practice time for the students is currently the respon- sibility of the instructor. However, instructors vary greatly in how they set up courses and the use of videotapes, work books, and information provided. Kaye et al. (25) observed that in 3-hour courses, the actual mannequin practice time ranged between 2 and 16 minutes per student. Additionally, Brennan and colleagues (29) noted that most trainees are not even minimally competent following training; most instructors simply pass or coach students to pass. Testing by an independent instructor on a fully computerized system resulted in failure of all students whom the instructor earlier had considered competent.

Kaye (33) suggests that lack of skill retention may reflect lack of initial skill acquisition.

Minimizing nonessential information that uses up practice time is essential. If the instructor has had personal experience in prehospital resuscitation it can add credibility to the training course but the sharing of personal experience also uses valuable time needed for skill practice. Actual personal experience relayed to students often results in students remembering the story and missing the underlying message.

Electronic devices such as CPR skill-prompting devices are effective in encouraging students to practice more effectively during the available time and for longer periods of time (59). If a prompting device is used at the point in the class when the students are beginning to loose interest in skill practice, even the most experienced adult students will be willing to practice for longer periods of time. Patterns (i.e., linked content) are retained and more easily accessed in memory than isolated facts or complex algorithms, even under stress. The prompting device will help to cement the pattern by consistently repeat- ing phrases such as, “head tilt–chin lift.” Students retrained at 2 years will report remem- bering the phrases repeated by the prompting device.

Positive Reinforcement

Positive reinforcement is essential if individuals are to develop self-efficacy, a key predictor of performance, as discussed above. According to psychological research on

“helping” behavior (60–67), issues inherent in the decision to act arise from the initial response to threatening, unfamiliar and/or complex situations. The decision to act depends on acknowledging that the situation exists and having confidence in one’s ability to handle the emergency (self-efficacy). Helping behavior research has focused on laypersons’

response to public assault, medical emergencies such as heart attack, and trauma such as uncontrolled bleeding, involving strangers. Research on laypersons’ response to CA in a family member is nearly nonexistent.

Skill Retention

Skill retention is directly affected by the amount of practice available during the learning process because the acquisition of psychomotor skills greatly depends on repetition (68). Overtraining has shown to improve retention (69–71). Overtraining is defined as continuing to practice a task after having achieved the performance criterion (72). Overtraining has been claimed to be of particular value in the retention of skills in which the individual has no chance to “warm up” (71), as is indeed the case during clinical CPR.

Other strategies recommended for improving retention include sensory input or feed-

back (73). Feedback received at the end of skill performance appears to be less effective

than that occurring during performance (74). Qualitative is not as effective as quantitative feedback (72). Improvement in performance depends on the frequency of feedback (72).

The person giving the feedback can be important as well. Feedback from a peer may be less threatening than correction from the instructor. If the observer is given a written checklist with the steps outlined, he or she can provide feedback and learn while observ- ing his or her peers.

Why do learners not perform CPR correctly after an interval when most people have no difficulty riding a bicycle several years after initial training? The answer is feedback.

When riding a bicycle, you receive instant feedback on how you are bicycling and con- sequently wrong performance is corrected. When performing CPR, little feedback is received. Feedback was more salient in the early training efforts. In the early training performed by Safar et al. (47) curarized nonintubated human volunteers would lie supine on the floor to demonstrate open airway and mouth-to-mouth ventilation. If the learners did CPR wrong, the “patient” would turn blue in a few seconds. That feedback changed their behavior and performance so that their technique created pink patients. In 1960, Lind (75) of Norway introduced the use of mannequins (instead of curarized patients) in the training of B-CPR steps A and B—a safer approach but one with little feedback (68).

Could we create a CPR “bicycle” or could an instructor play that role? Later, we propose the potential uses of technology to address these issues.

RETRAINING

Retraining of students 3 to 6 months following the initial CPR/automated external defibrillator (AED) course will result in better retention of skills. Review of skills can be as simple as asking students to demonstrate what they remember from their training class and then providing reinforcement for skill mastery and instruction in areas not mastered.

This approach was used in the Public Access Defibrillation (PAD) Trial and found to require only 5.3 ± 0.1 minutes for CPR and 7.8 ± 0.1 minutes for CPR + AED to test and retrain lay volunteers (75a). If the skill review is done individually with the instructor, the student is given individualized attention and peer pressure is eliminated. The skill review session also gives the instructor the opportunity to debrief students if any medical emergencies have occurred since the original training session.

Retention of CPR skills decreases significantly in a short period after training, even in medical personnel who are not routinely involved in resuscitation (33). Although skill decrement may reaches low levels, it is still above pretraining levels for most at 6–12 months (30,31,33,69,72,76–83). After initial training and early reinforcement, it is helpful if repeat remedial mannequin practice is made available every 6–12 months (31,33,69,72,76–80).

FUTURE DIRECTIONS

One night, a friend of Dr. Wik’s experienced a CA in an atypical patient—his mother—

lying on the bathroom floor, looking “dead.” His emergency medical technician mind

was not with him that summer evening. He was too preoccupied, too nervous just like any

other lone layperson facing such a situation. He did not think about details. Instead, he

thought, “call 911, bend the head back, grab the chin, pinch the nose, blow.” Then “hands

in the middle of the chest, and start pumping and blowing.” No rates or numbers were in

his mind. No complex and time-consuming steps regarding where to place his hands

crossed his mind. He just thought “pump and blow.”

Dr. Wik’s friend later realized that little of the real experience of people witnessing and acting during a CA is represented in our CPR education programs. This observation also was made by the lay bystanders surveyed regarding their thoughts, feelings, and motiva- tions when attempting to resuscitate a stranger (84). He came to recognize from his experience that CPR training has to be more readily accessible. It has to get to the right people, the people most likely to use it. It must to be perceived as being so easy that the actual learning of CPR is not even thought about or contemplated.

Technology and state of the art teaching methods are needed if we are going to achieve these goals. CPR practice that is routinely scenario-based to include professionals such as 911 dispatchers who will coach the performance will be more effective than traditional approaches. There have to be easily accessible home adjuncts such as speaker phones, a CPR prompt, and maybe someday, an even more user-friendly home AED as well as content-on-demand video instruction.

To achieve this dream, we will need to influence policy so that the government regu- lations of yesteryear are amended to rid our first aid and emergency cardiac care programs of superfluous content that is confusing and overwhelming to students. The data collected to date suggest strongly that this content is diffusing our message to a point that CPR learners cannot remember how to perform the most basic skills when needed.

To improve training and minimize human error, these authors believe that emergency cardiac care education must use behavior and education theory. Computer and virtual technologies like those being used in other life-essential skill domains such as pilot and physician training could be used. With simulation, expert performance can be modeled and immediate feedback obtained. With instant feedback and remediation from the simu- lator, CPR performance can only improve. There is technology available today—from simple clickers that give feedback when one has compressed deep enough to electronic feedback—that can give immediate feedback to students as they are learning. Earlier versions of these feedback devices were shown to improve learning, but were not used because they were misunderstood by the instructors. We now know that accurate and timely feedback is essential to learning and retention.

Technology soon to be available will provide not only immediate feedback but real- time verbal input as the student performs (85,86). Using virtual reality technology, the research team of Dr. Wik of Norway has developed a system that uses a type of video self- instruction synchronous practice in which almost the entire training and testing can be supervised from central control sites thousands of miles away. Internet learning cannot teach hands-on psychomotor skills and measure skill performance directly. But, as the human eye is unable to evaluate the adequacy of ventilations and compressions—and only instrumented manikins can do so—this technology will allow immediate feedback, regardless of proximity. Additionally, simulator mannequins now available can be pro- grammed with realistic attributes such as airways that swell, heads that are difficult to bend backwards, real lung sounds, distal pulses, agonal breaths, and so on. This technol- ogy is being used to improve the effectiveness of self-training and has been shown to increase learning and retention (85,86).

Perhaps in the future, as digital bandwidth expands, would-be rescuers might be able

to merely flick on their televisions to see a skills demonstration. Content-on-demand

technology could allow dispatchers to send the exact demonstration needed right to the

caller’s television, laptop computer, or personal digital assistant, rather than trying to

explain the sequence of steps verbally.

The real measure of success for CPR, AED, and other emergency cardiac care pro- grams is learner performance—bystander CPR and survivor rates. Building programs and course content, methods, and administration around learner outcome is essential. We now know enough about how to teach emergency cardiac care content. Until recently, we have focused on courses that are too long and taught by instructors with lecture notes and fixed minutes for manikin practice. These courses have focused more on the acquisition of cognitive knowledge than performance skills. A new approach is needed. These authors maintain that the traditions surrounding CPR training should be respected as our history but it is time to move on and totally revise CPR training programs to emphasize simplicity, essential skills, and the use of technology to broaden the population of those trained in CPR and the use of bystander CPR in our communities.

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