Video Clips on DVD
Knot-Tying: A Guide to Tying Surgical Knots and Common Knot-Tying Mistakes
Feedback in Surgical Training
The results of learning to operate are observed in a surgeon’s performance, but the process is much less obvious. The teaching model has historically been that a good surgeon is also a good teaching surgeon; although most of us do not always have a clear understanding of the best way to teach. The goal of this chapter is to help surgeon educators improve their teaching strategies. Understanding the factors that lead to effective learning should help us determine how we teach. Learning surgical skills primarily involves focused, repetitive practice and receiving appropriate feedback based upon valid and reliable assessment of performance. First, we will briefly review the educational theories that are applicable to teaching surgery. Then, each of the key components of effective teaching and learning, including practice, feedback, and assessment, will be explored in detail with the hope that surgeons may improve their teaching.
A foundation in educational theory may help surgeons develop basic understanding of the principles and mechanisms behind how trainees learn to perform procedures in surgery. The theory of behaviorism is most closely associated with B.F. and involves the experimental analysis of behavior. Skinner contended that organisms exhibit certain behaviors in relation to their environment. He argued that we should look at what occurs before the behavior and the consequence of the behavior. Because the consequence reinforces or eliminates the behavior, Skinner proposed that learning is contingent upon reinforcement. If we apply behaviorist theory to the surgical setting, the only evidence we have that a trainee has learned to operate comes from the trainee’s actual surgical performance. By observing this “behavior” in the operating room, skills can be improved or eliminated. For example, a trainee is more likely to operate if he/she knows all details of a patient’s history and physical examination and has reviewed the relevant anatomy. Therefore, the specific behavior of thoroughly preparing for the case is positively reinforced with participation in the surgical case. Behaviorist principles and an example of their implementation in the surgical setting are illustrated in Figure 13-1 .
To assume that we can only improve teaching by understanding what trainees do, rather than what they are thinking, is short sighted. Surgeon educators need to also understand what is going on in a trainee’s mind during the performance of a surgical skill. Behaviorist principles fail to account for how the trainee processes the information that is to be learned. Therefore, it is helpful to understand some elements of cognitive information processing. According to the cognitive-information-processing view, learning is similar to the processor on a computer. Information is put in the mind from the environment, processed and stored in memory, and output is in the form of a learned behavior. Unlike behaviorism, there is an intervening variable that exists between the environment and the performance of the skill. That variable is the information processing system of the trainee. proposed a theory of memory which states that from the time information is received by the processing system, it undergoes a series of transformations until it can be permanently stored in memory. For example, while a trainee is performing a hysterectomy, an unclamped uterine vessel starts bleeding. Attention is drawn to this by the teaching surgeon, and the image of the bleeding vessel enters the trainee’s sensory memory. The task of placing a clamp over the vessel is performed or rehearsed and becomes a part of the trainee’s working memory. The desired response of improved bleeding (hemostasis) leads to this particular scenario becoming a part of the trainee’s long-term memory.
Why is it important to understand how a trainee processes information? Because embedded into the information learned for new surgical procedures are critical cues that the experienced surgeon recognizes but a novice trainee has difficulty discriminating out of the large volume coming into the mind. For example, visual information decays after about 0.25 second and auditory information decays after about 4 seconds. It is currently unclear how long tactile information stays in sensory memory. Experienced surgeons already have stored the operations in memory and thus have learned to ignore most of this information as they relate it to normal parts of the procedure; therefore, they tend to focus on other aspects of the case such as variations and problems. As a result, experienced surgeons suffer from automaticity. An example of an overlearned skill that becomes automatic is knot-tying. Automaticity occurs when tasks are overlearned or incoming sources of information become habitual, to the extent that attention requirements are minimal. Experienced surgeons suffer from this because, when one’s role is to teach techniques that have become automatic, it is difficult to recognize these techniques as important steps in the process of learning. For the experienced surgeon, when something out of the ordinary occurs during a procedure they shift out of a mode of automaticity and into a mode of selective attention. Selective attention is a surgeon’s ability to select and process certain information while simultaneously ignoring other information. The teaching surgeon should draw attention to these critical cues that they have learned to recognize and help the trainee understand how to discriminate them from background information.
K. Anders Ericsson compiled at least two major advances in understanding how psychomotor skills are learned during acquisition and maintenance of expert skill performance. The first is the need for repetitive, focused practice. The second is the need for feedback. An expert’s performance continues to improve as a function of increasing experience and deliberate, focused practice. calculated that becoming an expert musician, master chess player, or expert athlete requires about 10,000 hours of deliberate and distributed practice. The importance of deliberate and repetitive practice can be applied to surgical trainees as well. The benefit from repetitive practice is not limited just to trainees early in the learning process. It is useful throughout a surgeon’s career and may be particularly useful for the most senior surgeons. This is somewhat contrary to the long-standing belief that the most experienced surgeons deliver the highest quality care. A large systematic review by looking at the relationship between clinical experience and quality of health care suggests that surgeons who have been in practice longer may be at risk for providing lower-quality care if practice is not continued throughout one’s career. Furthermore, aging appears to have a negative effect on the ability to learn new motor movement due to a decrease in mental encoding of motion. The motor cortex may not effectively reorganize and accommodate new information in surgeons older than 50 compared to younger individuals. Hand function and manual dexterity also deteriorate as a consequence of aging, as does the ability to control force with each finger. However, demonstrated that older adults can reach performance levels comparable to younger adults but doing so requires extensive practice. This indicates that older physicians may need more quality improvement interventions and repetitive practice when maintaining and learning new surgical skills.
The second important principle is that even experts should be provided with immediate, direct, and relevant feedback on their performances. Together, time spent practicing a skill is most useful when trainees reflect on or receive feedback on their performance, and have numerous productive practice sessions distributed over time rather than the same number of hours compressed into one day’s session. As a general rule, frequent practice sessions of any skill with intermittent rest periods appear to be better than mass training in a single session. Although this makes sense, this is not universally practiced in today’s surgical training programs. The questions remaining are: What are the best methods of deliberate and repetitive practice? How does one provide appropriate feedback? What should be assessed, and what are the most useful methods of assessing that one has learned a surgical skill?
Target Basic Automated and Correct Surgical Techniques
A usual starting point in skills teaching is to begin with surgical skills in which experienced surgeons have already achieved a level of automaticity. Suturing and knot-tying are examples of automated skills. That is, when tying a surgical knot, expert surgeons do not consciously think of the steps in order to accomplish the task. Once the surgeon reaches a phase of automaticity, it becomes increasingly difficult for surgeons not to overlook automated techniques when teaching. However, automated techniques are important for teachers to recognize because these techniques may be difficult to remedy once bad habits form. Therefore, it is essential that correct technique is demonstrated from the beginning of the learning process.
After choosing the skill to teach, one approach is to use error-training. This method begins by teaching correct technique. Once the trainee understands how a task is correctly performed, the next stage is to teach the trainee to recognize errors in technique and eliminate them during practice. randomized 30 medical students to one of four training methods of tying two-handed surgical knots: (1) no instruction, (2) erroneous technique instruction, (3) correct technique instruction, or (4) combined correct and error technique instruction. The students were asked to perform a two-handed square knot, before and after viewing the instructional videotape. There was a significant improvement in assessment scores in the group receiving both the correct and error instructional techniques. This demonstrated that teaching trainees how not to perform a task, or common errors in performing the task, along with correct technique is more valuable that either method alone.
Common errors when learning basic knot-tying include the following:
Failure to maintain tension: It should be explained to the trainee that failure to maintain tension on the suture while tying increases the chance of slippage off the tissue and can be extremely dangerous when tying a vascular structure. This error most likely occurs as the trainee gains speed in knot-tying, and it is helpful to have the trainee slowly perform the task while demonstrating correct technique.
Air knots: An air knot is caused by failure to push the suture past the knot. Failure to completely snug the knot down creates a space between consecutive knots. The space between knots compromises the security of the knot and may cause the knot to slip off the pedicle. Slowly performing the task may be helpful in evaluating this error.
Holding the suture too close to the knot: This compromises efficiency of movement by making it too difficult to pass the suture strand through the loop. This increases the time to place the knot and decreases efficiency of knot-tying. The suture should be held at least 5 cm away from the knot.
Slip knot: This knot is caused by incorrectly crossing the strands of a square knot or by failure to reverse the hands when placing horizontal tension after each throw. A slip knot is not a secure knot and can easily loosen.
See DVD Video 13-1, Knot-Tying: A Guide to Tying Surgical Knots and Common Knot-Tying Mistakes, for a correct demonstration of surgical knots and a demonstration of common errors.
Break Procedures Down into Manageable Steps
When preparing a lecture on a clinical problem one might outline the lecture beginning with epidemiology, pathophysiology, clinical presentation, treatments, and prevention. The topic of the lecture is broken down into concepts and by understanding the relationships between these concepts one can apply them to individual patients in the clinic. Similarly, in teaching procedural skills, it is helpful to break a procedure down into important tasks or manageable steps.
One important task during vaginal hysterectomy is clamping, cutting, and tying of a pedicle. See Table 13-1 for the manageable steps of a vaginal hysterectomy. recorded 23 trainees during individual tasks of clamping, cutting, and suturing the left uterosacral ligament while performing a vaginal hysterectomy. Using motion analysis software to break down the procedure into discrete parts, differences in measurements such as time, angle, velocity, and hand trajectory of various steps emerged between novice and experienced surgical trainees. For example, at the start of suturing the uterosacral ligament pedicle, experienced trainees placed the Heaney clamp closer to a right angle to the vertical axis compared to novice trainees ( Fig. 13-2 ). In this case, holding the Heaney clamp close to 90 degrees from the vertical axis allowed for easier and faster suturing. It also allowed teaching surgeons to provide more deliberate focused teaching to the training surgeon. For example, this technique could then be communicated as, “Hold the Heaney clamp at a 90-degree angle to the bladder retractor, and it will be easier to see the needle as it passes through the tissue and will eliminate unnecessary passes of the needle.”
Surgical simulation provides opportunity for repetitive practice of surgical skills outside the operating environment. Simulated surgical environments are gaining popularity due to several factors: poor teaching in high acuity and fiscal pressured operating rooms; work-hour restrictions on surgical trainees that result in decreased operating room exposure and less opportunity for repetitive practice; increased public awareness that surgeons demonstrate competency prior to operating on live patients; and public demand to minimize medical errors and iatrogenic injury to patients. The goals of surgical simulation are to create safe, controlled, reproducible environments that resemble real-life clinical situations and surgeries. Simulators clearly offer a compelling reason to reduce reliance on patients, cadavers, and animal models for surgical training, and some data suggest they may be just as good as other forms of surgical training. Moreover, surgical simulation in gynecology has been shown to be beneficial and superior to operating room experience alone. Studies have demonstrated that training in a skills laboratory may significantly shorten operating room time, increase patient safety, and reduce patient morbidity.
Low-fidelity simulators use less realistic materials and equipment, and are more useful for performing a simple task such as knot-tying or suturing. The American College of Obstetrics and Gynecology Surgical Curriculum includes examples of portable bench models that are easily constructed for teaching basic skills required for most common gynecologic procedures. For example, abdominal fascial closure can be simulated using a folded towel. Suture is used to reapproximate the towel edges with interrupted, continuous, and Smead-Jones stitches. Isolation and ligation of a vessel is simulated using a placenta and hemostats, scissors, and suture. This task evaluates the trainee’s ability to isolate a vessel, clamp the vessel, divide the vessel, and tie both pedicles with square knots. The task can also be practiced with a tie on a passer. Ligation of a pedicle can be practiced with strips of bacon, Heaney clamps, and suture. This task evaluates the trainee’s ability to place a Heaney clamp, place a Heaney stitch, and tie secure square knots.
Video box trainers are used for laparoscopic training, using real surgical instruments, endoscopes, and video screens. They provide an opportunity to practice basic skills required in any laparoscopic procedure, including eye-hand coordination, camera handling, grasping mechanisms, suturing, cutting, and clip applying. A study by Banks and coworkers (2007) randomized obstetrics and gynecology trainees to either laparoscopic simulation curriculum or a no-simulation group. Residents with simulation experience had higher scores than control subjects performing a tubal ligation on a live patient. Similar findings were reported by for the task of performing a salpingostomy for ectopic pregnancy. In gynecology, low-fidelity simulators exist for both vaginal and abdominal hysterectomy, cystoscopy, sacrocolpopexy, sacrospinous ligament fixation, colpocleisis, and obstetric sphincter laceration.
High-fidelity simulators use realistic materials, provide realistic cues to create a more realistic environment, and are used more often for surgical procedure training. High-fidelity simulators include animal models and virtual-reality simulators. Animal models, usually pigs, are useful for teaching complex laparoscopic techniques, but are limited by costs and availability. Similar to the video box trainers, virtual-reality simulators evaluate common laparoscopic skills, such as use of a 0-degree or 30-degree endoscope, eye–hand coordination, grasping, suturing, and clip-applying. Virtual-reality simulators create a more realistic scenario for laparoscopic techniques and procedures, record and save performance data, provide objective feedback, and allow the level of difficulty to be set. Disadvantages include costs and lack of haptic or tactile feedback.
Mental imagery can be a very effective means of encoding information, and there is some evidence that mental practice can improve surgical performance. Encoding refers to the process of relating incoming information to the concepts already in memory so that new material becomes more memorable. Mental imagery involves the cognitive rehearsal of a task with or without physical movement. The first theory behind mental practice postulates that muscle firing in the correct sequence strengthens muscle memory. The second theory is based on the development of mental blueprints that are rehearsed repetitively with mental practice, causing the behavior to become automatic. Widely used in sports, this technique has been shown to not only help a trainee acquire certain skills (cognitive imagery), but it can also help emotionally prepare a trainee to perform under stressful situations (motivational imagery). Mental practice in sports has been shown to be most effective when it is brief (no longer than 20 minutes) and when performed immediately before the task is to be performed. Prior to performing a hysterectomy, asking the surgical trainee to mentally rehearse each step of the procedure from abdominal incision to closure may be helpful. This may help trigger questions regarding portions of the procedure that are unclear so that they may be answered prior to starting the surgery.
There are also some data using mental imagery in surgical skills training. randomized 44 medical students to a 1-hour session on mental imagery, mental imagery with hand movement, or standard Advanced Trauma Life Support for the task of emergency cricothyrotomy. After 1 week, results on an Objective Structured Clinical Examination found that scores of the students who underwent mental imagery with physical movement were higher. Some surgeons incorporate mental imagery into the preoperative preparation of their trainees, reporting it to be a valuable addition to learning surgical procedures.
In addition to repetitive practice, verbal feedback from an expert is a key factor in learning to correctly perform any skill. One study randomized novice medical students to a group that received computer-assisted instruction on knot-tying and a second group to receive a lecture using a slide presentation with individual live feedback while performing the task. Both groups were able to tie a square knot with no significant difference in total time, but the individual feedback group had better performance scores reflecting the quality of the technique and knots.
Feedback sessions should be an active dialogue between a trainee and a surgeon composed of skills or competencies relevant to the trainee’s ultimate learning objectives. The following are general principles of providing formative feedback:
Useful feedback is timely, specific, and describes specific behaviors, knowledge, or attitudes that have been witnessed—not personal traits.
The surgeon’s role is to help the trainee reflect on problems in a nonjudgmental way.
Whenever possible, the surgeon should ask questions rather than offer interpretations.
Feedback sessions should be mutually convenient.
Confidentiality of the trainee should be maintained.
It is also essential that feedback is provided early in the learning process to prevent learning of incorrect motor habits, which are difficult to remedy. Feedback can be given before, during, or after the skill is performed. It may occur at the end of the day in the operating room or at the end of a rotation.
Before practice it is critical to communicate what the objectives are and what level of performance is expected to achieve the objectives. (For examples of writing clear learning objectives, the reader is directed to , and .) The trainee then needs an overview of the skill and how it would be performed by an expert either by demonstration or examples. After practice, a trainee needs to be given feedback on selective items of the performance and the results of that performance. In general, this feedback should be constructive and immediate.
In our experience, starting the feedback process can make the surgeon and trainee feel somewhat uncomfortable, as it may feel out of the normal routine, and the trainee may feel as though you are scrutinizing his/her performance. suggests beginning the process by describing the difference between “quick” and “formal” feedback and how and when each occurs. Formal feedback is usually associated with assessment, and quick feedback is more associated with teaching. Although the aim of both is to improve performance, the observations that are made in formal feedback are more global and usually cover a period of time. Formal feedback often includes a comparison between early and current skills/knowledge. Quick feedback addresses observations “in the moment.” Remind the trainee that they can initiate the feedback process by asking specific questions. Finally, discuss learning goals. For example, “While we are working together during this rotation, I will expect that you will ask a lot of questions. I will ask a lot of questions, too. From your answers, I’ll get a sense of what you know and what you don’t know yet. I am going to encourage you to periodically self-assess.”
Giving immediate feedback can be difficult, especially in a busy, stressful operating environment. One model that can be used is the Ask-Tell-Ask Model, described by Taylor. This model is an effective template for providing feedback that focuses on learners’ self assessment, giving you the opportunity to reinforce appropriate behavior (behaviorism) and correct faulty reasoning or technique. This model should be used before and after a surgical procedure. With this model of feedback, you ask trainees to assess their performance. If they have a concern about their performance, briefly address that concern. By focusing on the learners’ concerns, you help them develop self-assessment skills while providing corrective feedback. The model is as follows:
Ask for the trainee’s self-assessment. Be specific, but leave room for comments about all tasks assigned. For example, “That was a difficult surgical case. How do you think the procedure went?”
Acknowledge and address the trainee’s concerns.
State your observations.
Provide feedback on at least one task that the trainee performed well.
Address a maximum of one or two other areas for improvement.
Provide focused teaching.
Check the trainee’s understanding.
Discuss a plan for improvement.
See DVD Video 13-2, Feedback in Surgical Training, for a demonstration of the Ask-Tell-Ask feedback technique.
The most effective feedback is explicit, literal, and detailed. An example of poor feedback is, “Drive your needle through the uterosacral pedicle, not the uterine sidewall.” A more effective statement is, “Hold the Heaney clamp at a 90-degree angle to the bladder retractor. This allows you to visualize your needle tip as you drive it through the tissue at the tip of the clamp, and prevents driving it through the uterine sidewall.” Also, simply directing the trainee isn’t necessarily the most effective way of teaching. When possible during surgery, it is often helpful to ask the trainee why a particular task or technique is essential, which may help the trainee understand the basis behind the technique and how the technique is performed. This process allows the trainee to relate the new information to existing knowledge, gain a deeper understanding of the skill, and may potentially improve retention and application of that skill to other associated scenarios.
Video playback has become another popular method of giving visual feedback. Video footage reduces subjectivity introduced with retrospective methods of feedback by allowing the instructor and learner to view the performance multiple times and evaluate the performance as if in real time. Video can also provide a means to break down the procedure into components or frames in order to examine every move the trainee makes, allowing the instructor to provide detailed feedback. demonstrated how videotaped review of basic skills such as knot-tying can allow trainees to identify areas for improvement from their own performance allowing for practice on models or simulators prior to reattempting the task in the operating room.