TRAINING BRONCHOSCOPISTS FOR THE NEW ERA

FLEXIBLE BRONCHOSCOPY UPDATE

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TRAINING BRONCHOSCOPISTS FOR THE NEW ERA Paul A. Kvale, MD, and Atul C. Mehta, MD

Gustav Killian introduced bronchoscopy a little over 1 century ago. At that time, the only way others could learn how to perform bronchoscopy was by one-on-one tutoring, using a rigid bronchoscope with no side portals and no imaging devices such as a television camera and monitor. One-on-one teaching remains an integral part of learning how to perform bronchoscopy well, but many new technologies have emerged that make it far less labor intensive to train bronchoscopists. The flexible bronchoscope, which was developed in the 1960s, generally is regarded as an easier instrument to use than a rigid bronchoscope. Beam splitters became available in the 1970s, so the primary operator and the student could view the image at the same time. In the 1990s, charge-coupled device (CCD) technology allowed manufacturers to incorporate a chip into the tip of a flexible bronchoscope with digitization of the image and reconstruction of an analog image on a television monitor. Such monitors can be placed wherever they are wanted, allowing many students to observe the findings and the techniques of bronchoscopy at the same time. For "live" bronchoscopy of patients, a teacher of bronchoscopy still needs to be positioned at the tableside, in close proximity to the stu-

dent, when the procedure is performed. This positioning allows the nuances of manipulating the bronchoscope and the various ancillary instruments (biopsy forceps, and so forth) to be taught as well. More recently, simulators have been developed for flexible bronchoscopy training, and most of what can be learned with live patients is reproduced well with these simulators. The use of simulators is standard in many professions in which proper training can improve the safety of the task. Examples include the military,30aviation,3l nuclear and aerospace i n d ~ s t r i e sSimulators .~~ are used for training, rehearsal, and competency evaluation. Flight simulators are used to train novice and expert pilots before flying new types of aircraft, for example. Pilots must be certified on simulators before they are allowed to fly commercial planes.26 The application of simulation technology to endoscopic medical procedures began in the early 1990s, with the emphasis on gastrointestinal endoscopic p r o c e d ~ r e s .5*~13* , 27, 36 The technology at that time was not advanced enough to produce realistic or affordable simulators. One of the biggest technical hurdles was that these simulators required computers that cost approximately $250,000. Fortunately,

From the Division of Pulmonary and Critical Care Medicine, Henry Ford Hospital, Detroit, Michigan (PAK); and Department of Pulmonary and Critical Care Medicine, Cleveland Clinic Foundation, Cleveland, Ohio (ACM)

CLINICS IN CHEST MEDICINE VOLUME 22 * NUMBER 2 * JUNE 2001

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recent technologic advancement has allowed introduction of a flexible bronchoscopy simulator (FBSi) that is realistic and runs on a desktop personal computer? In addition to endoscopy, simulation technology is being applied to laparoscopy,12anesthesia,’O cardiol0gy,14 and percutaneous procedures.= Physicians are beginning to realize the potential benefits of simulation, as evidenced by recent publications urging the medical community to adopt this technology for training and certifi~ation.~,l7 Simulators offer the potential to minimize the necessity to learn and practice procedural skills on patients, allowing trainees to develop basic competence before treating patients. The justification of patients being subjected to the ’/see one, do one, teach one” training method is nearing the end. Although this phrase is used commonly in the back halls of medical training, responsible teachers always have felt the need to supervise students closely to optimize the learning process and ensure patient safety at the same time. Now, however, simulators will replace the need to practice procedures on recently deceased patients, a practice coming under intense scrutiny lately.l* In addition, the use of animals for medical procedure training will become less necessary, reducing the high cost of operating animal laboratories. Medical credentialing organizations, such as the American Board of Medical Specialties, also are beginning to investigate the use of Prosimulation for evaluating clinical ~kills.3~ fessional medical organizations such as the American College of Surgeons, the American Society of Gastrointestinal Endoscopists, the American Academy of Orthopedic Surgeons, the Society for Cardiovascular and Interventional Radiology, the American Urological Association, and the American College of Cardiology are investigating the use and development of medical simulators. FLEXIBLE BRONCHOSCOPY SIMULATOR In 1995, members of the bronchoscopy community also recommended the develop-

ment and use of simulators for bronchoscopy training.33 In 1999, the first commercially available FBSi (HT Medical Systems, Gaithersburg, MD) was introduced. The simulator consists of a proxy flexible bronchoscope (FB), a robotic interface device, a computer with monitor, and simulation software. These components combine to create a realistic and immersive training environment for learning and practicing flexible bronchoscopy. As shown in Figure 1 (see also Color Plate 1, Fig. 5), the user inserts the proxy bronchoscope into the robotic interface device. The bronchoscope feels and acts like an actual FB. The interface device tracks the motions of the FB and reproduces the forces felt during an actual bronchoscopic procedure. The proximal end of the interface device is shaped like a human face with a port to insert the FB through one of the nasal passages. The FB tracks the manipulations of the tip control lever, suction button, keyboard input, and foot switch. In addition, instruments are tracked as they are manipulated in the working channel. This tracking allows for biopsies and other diagnostic and therapeutic procedures to be performed on the simulator. Not all live bronchoscopy is set up the same way (suction buttons, foot switches, and so forth), but these differences are not a deterrent to the primary purpose behind use of a simulator. The monitor displays computer-generated images of the airway as the user navigates through the virtual anatomy. Figure 2 (see also Color Plate 1, Fig. 6 ) demonstrates an example of the anatomy at the level of the carina. The three-dimensional computer-generated models of the airway are constructed using high-resolution computed tomography (CT) scan data sets or other appropriate data sources such as the National Library of Medicine’s Visible Human Pr0ject.l Texture maps based on videotapes of actual bronchoscopic images are added to the airway models to give the mucosa a realistic look. Using different CT scan data sets allows for the development of a variety of simulated cases that reflect a wide range of patient anatomy and pathology. In addition to being anatomically correct, the virtual patient also behaves in a physiologically realistic manner. The patient breathes,

TRAINING BRONCHOSCOPISTS FOR THE NEW ERA

Figure 1. Flexible bronchoscopy simulator. A = Proxy bronchoscope; B and C = Robotic interface. (See also Color Plate 1, Fig. 5.)

Figure 2. Simulated bronchoscopic image as seen on the monitor. Right hand panel depicts procedure-relatedoptions. (See also Color Plate 1, Fig. 6.)

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thesiologists is becoming more common, escoughs, bleeds, and exhibits changes in vital pecially for difficult intubations. To the ausigns (pulse rate, blood pressure, oxygen saturation, respiration rate). Programming inthors' knowledge, this group of physicians receives little formal bronchoscopy training. cludes complications such as lidocaine toxicSimulation of difficult intubations is also ity causing the patient to seize or develop available to aid novice anesthesiologists. cardiac arrhythmias. Bronchoscopy simulation also can be used The simulation software records all the acto train health care providers who assist in tions of the user and stores this information in a database. Information that is collected bronchoscopy. Bronchoscopy nurses, techniand displayed includes time of the procedure, cians, and respiratory therapists can use the simulators to learn airway anatomy and to number of times the bronchoscope tip collides with the airway wall, percentage of bronchial understand the wide range of bronchoscopic segments entered, and the amount of lidoprocedures and make their participation more caine used. Appropriate use of lidocaine and effective. Simulators could allow this initial training the suction device improves ease of the procedure and avoids "collisions." to occur in a time-efficient and cost-effective The software runs on a personal computer manner. In a short time, fellows can be exwith 500 Mhz Intel Pentium 111 Processor and posed to a broad range of cases that reflect Microsoft Windows NT. It also requires a variations in patients' anatomy, pathology, graphic accelerator card. and physiology. This training can occur in a more organized and predictable fashion outAt the Cleveland Clinic Foundation, the side the endoscopy suite without burdening simulator has been evaluated for its effectivethe actual bronchoscopy procedures and inness and used for the past year to train pulvolved patients and personnel. It also has a monary and general and cardiothoracic anespotential of greater cost-effectiveness. thesia fellows, out-of-state observers, and Complications such as hemorrhage, pneusmall group demonstrations. In a prospective multicenter study, this simulator was successmothorax, lidocaine toxicity, and cardiorespiful in differentiating between novice, experts, ratory distress and their management options and individuals who never performed a flexcan be programmed into a simulated case. ible bronchoscopy using parameters such as Medical simulators currently are being used duration of the procedure, airway collisions, in anesthesia for crisis management training'l and the thoroughness of the examination.25 This use is analogous to pilots using flight simulators to practice their responses to unexBased on that experience, the authors believe that the FBSi could impact three major pected disasters such as power failure or the loss of an engine in mid air. areas-(a) training, (b) procedural planning, and (c) bronchoscopic credentialing. PRACTICING TRAINING

Simulators can be used to train new residents and fellows, experienced bronchoscopists, and other health care providers, such as nurses and respiratory therapists, who assist in bronchoscopy. Pulmonary fellows and other physicians who learn bronchoscopy can gather their training on a simulator before the first patient contact. Use of the simulator can take individuals up the learning curve rapidly, boosting their confidence and facilitating patient comfort and safety. The use of flexible bronchoscopes by anes-

Experienced bronchoscopists also could benefit from the simulators by working on their limitations. Simulators provide exposure to and allow practice of newer endoscopic or advanced or difficult procedures such as transbronchial needle aspiration (TBNA), transbronchial biopsies, bronchoalveolar lavage, electrocautery, tracheobronchial expandable metallic stent placement, and the use of lasers with flexible bronchoscopes. The adoption of these procedures by practicing physicians is hindered in large part by the lack of access to adequate training. In the

TRAINING BRONCHOSCOPISTS FOR THE NEW ERA

near future, simulators should be able to remove such barriers. As yet, however, simulators have not been developed to assist in teaching rigid bronchoscopy, a technique that still is needed for approximately 5% of all bronchoscopic procedures. Rigid bronchoscopy is still the preferred instrument for massive hemoptysis, pediatric bronchoscopy, airway foreign bodies, and (in the opinion of many) optimal laser bronchoscopy and stent placement-especially silicone stents. Simulators also have a potential to be used for preprocedural planningz1 The CT scan data of a patient who needs an airway stent, for example, can be downloaded into the simulator before the procedure. The bronchoscopist then can practice placing an expandable metallic stent on the simulator so critical decisions such as stent sizing can be made more accurately before the actual procedure. Such simulation, when available, could decrease complications and improve success, eliminating unnecessary cost and time associated with lengthy or repeat procedures. Computer programs are under development to include all diagnostic and therapeutic endoscopic procedures in the simulators.

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to develop a benchmark that physicians must attain before being deemed competent at bronchoscopy. The benchmark can be established by developing an extensive database of performance by competent bronchoscopists on a set of standardized cases on the simulator. Extensive studies are necessary to evaluate and validate medical simulators before adopting their use for certification purposes. Studies are underway to address these issues.2,3, 6, 8, 11, 21, 25, 29 The rigorous testing used in the validation of flight simulators must be applied to medical simulators. This testing is no longer a technical challenge but only a matter of time and resources. COST OF SIMULATORS

Such simulators are available at the cost of close to $25,000. With time and improvements in technology, this is likely to improve and be more affordable. ADDITIONAL PREPARATION BEFORE AND DURING LIVE PATIENT LEARNING EXPERIENCES

CREDENTIALING

Bronchoscopy simulators could revolutionize the evaluation of bronchoscopy skills. To date, there is no objective means of measuring cognitive and psychomotor skills of bronchoscopy. Written or oral examinations can test some cognitive skills but provide no measures of psychomotor skills that are essential for bronchoscopy. The establishment of a minimum number of bronchoscopies that a clinician must perform to achieve competence has been discussed,2, 3, 16, 21, 29 even though agreement on the exact number has not been reached. In addition, performance of a minimum number of procedures does not always correlate with actual skills.8 Simulators can record all decisions and actions made by the user. Such a database allows for training programs to assess the skills of trainees and track their progress over time. In addition, credentialing and certifying organizations will be able to use simulators

A core curriculum is an integral part of preparing a student of bronchoscopy. Standard textbook material is plentiful, but key articles on various aspects of bronchoscopic practice should be required reading for students of bronchoscopy. In addition, an atlas of still bronchoscopic photographs and teaching videotapes are invaluable to prepare the student for subsequent live patient experiences. Teaching videotapes usually include more than what is seen through the bronchoscope in the patient; also included are overviews of how to manipulate the instruments, position the patient properly, use ancillary equipment such as fluoroscopy to guide placement of instruments, and other useful information. The student also should be taught practical things-for example, where medications and resuscitation equipment are kept and the different types of diagnostic sampling instruments and where they are stored. The student also should learn about the various parts of

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the bronchoscope, light sources, amplifiers, and photographic recording equipment. Cleaning and maintenance of this equipment should be learned as well. If fluoroscopy is available, the student should be taught safety principles, how to minimize exposure times, and so on. The need for careful and accurate labeling of specimens must be emphasized. It may seem intuitive that the student of bronchoscopy is expected to know the details of each patient about to undergo the procedure, but this point may need emphasis. This knowledge includes familiarization with each patient’s history and physical findings and a review of all relevant diagnostic imaging. Optimal bronchoscopy for a patient suspected of having lung cancer, for example, includes sampling enlarged mediastinal lymph nodes to stage the cancer at the same time. Chest CT scan examinations must be performed before the initial bronchoscopy, and the location of lymph nodes in relation to bronchoscopic landmarks must be determined before the procedure is started. It is useful to reverse the CT scan images when planning TBNA because this provides an orientation that is identical to what the bronchoscopist sees as the examination is performed. Advanced techniques (such as endobronchial ultrasonography mapping, real-time CT scan fluoroscopy for TBNA, and so forth) will be used more commonly in the future. These skills can be introduced to the student in the later years of training. Prevention of complications and optimal sampling during the procedure also require education. The most common complication is bleeding, and its prevention is not assured by performing a ”coagulation profile” before the procedure.” 28, 29 Instead, the student should be taught to take a careful history of excessive bruising or bleeding with prior trauma or surgery and ingestion of medications known to interfere with blood coagulation, and to schedule the procedure after eliminating or correcting these risk factors. Likewise, a ”shotgun” approach to processing samples retrieved at bronchoscopy leads to excess cost and no improvement in diagnostic yield. Selective sampling and processing of bronchoscopic material should be based on the science that is reported in properly done studies

on the subject. An example is that routine processing of bronchial washings for tuberculosis is wasteful.2O TRAINING WITH LIVE PATIENTS

Because not all training programs are likely to purchase simulators, this fact alone will create a need to continue training bronchoscopists ”the old-fashioned way” with live patients. Even training programs that acquire simulators will need to move the bronchoscopy student into the live patient arena. Moreover, the lack of availability of a simulator for rigid bronchoscopy continues to create the need for one-on-one training in these techniques. It is the authors’ practice to transfer increasing responsibility gradually to bronchoscopy trainees as they work with live patients. Two of the more difficult parts of performing a diagnostic flexible bronchoscopy are the transnasal or transoral passage of the instrument and intubating the trachea. These two things happen first and they produce the most discomfort for the patient. In the interest of assuring patient comfort and safety, the novice bronchoscopist therefore typically is allowed some ”driving time” in the airway of a live patient after the patient is intubated by the instructor or a trainee with more experience. By allowing the novice bronchoscopist about 5 minutes of ”driving time,” the goals of acquiring skills of staying in the airway lumen, avoiding ”collisions” with the airway wall, and recognizing abnormalities can be combined with an ”optimal procedure” from the perspective of patient comfort and maximizing the diagnostic yield. When the novice bronchoscopist demonstrates adeptness at these initial “driving skills,” additional responsibilities such as the transnasal or transoral passage of the instrument and intubating the trachea follow. Three separate actions are involved in moving the bronchoscope through the airways: (1)rotation of the entire bronchoscope; (2) use of the lever that controls flexion and extension of the tip of the instrument; and (3) forward movement (or withdrawal) of the bronchoscope. The typical novice bronchoscopist separates these three actions and improves them into a coor-

TRAINING BRONCHOSCOPISTS FOR THE NEW ERA

dinated, complex maneuver as experience is gained. The authors suggest that the student be required to demonstrate his or her expertise in performing all these manipulation skills before allowing him or her to use sampling instruments. Observation of how these instruments are used, with the simulator or with live patients, should precede the student's actual obtaining of samples. This requirement allows instruction of how to minimize trauma while performing brushings and biopsies or using a transbronchial needle. Damage to the flexible bronchoscope is less likely when these techniques are emphasized." Students typically learn to manipulate the bronchoscope, by simulator or live patient experiences, by watching the image on a television monitor. Because some bronchoscopes that are and will remain in use in the upcoming years are not video bronchoscopes, it is important that the student be taught to look through a fiberoptic bronchoscope as well. Manipulation of the instrument while doing so is a somewhat different experience than manipulating the bronchoscope while looking at the television monitor. Another key point to teach a student pertains to sampling an endoscopically invisible abnormality in the periphery of the lung. The student must be taught to look at the fluoroscope monitor while manipulating the tip of the bronchoscope as the lesion is approached with sampling instruments. Likewise, real-time CT scan fluoroscopy or endobronchial ultrasonography requires the bronchoscopist to look at those images while taking samples from abnormal lymph nodes rather than to look at the bronchoscopic image. LEARNING RIGID BRONCHOSCOPY

Not all bronchoscopists need to become proficient at rigid bronchoscopy. Typically this training comes as an integral part of otolaryngology residencies; fewer pulmonary physicians receive such training. Most of what is to be learned requires extended training in the old-fashioned "one-on-one" methods of teaching. Practice with intubation using a direct laryngoscope is a good preamble.

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Monocular visualization may be improved by having the student practice observing objects through a straw. A model for intubation with a rigid bronchoscope is helpful because simulators are not currently available for rigid bronchoscopy. The teacher must emphasize the greater potential for trauma to the upper airway and to the bronchi, such as damage to the teeth and soft tissues, laceration of the larynx or the bronchial mucosa, and the like. Lightweight cameras are available and can be attached to a quartz rod telescope, so the teacher can "coach various nuances of manipulating a rigid bronchoscope. Acquisition of excellent manipulative skills, however, requires direct visualization through the telescope. The student and the teacher need to share time looking through the telescope and adjusting tip position, using the suction catheter, forceps, laser fiber, and so on. Becoming proficient with these complex maneuvers usually takes a year or more of close interaction between student and teacher.19 References 1. Ackerman MJ: The visible human project. Proceedings of the IEEE 86:504-511, 1998 2. American College of Chest Physicians, Section of Bronchoscopy: Guidelines for competency and training in fiberoptic bronchoscopy. Chest 81:739, 1982 3. American Thoracic Society: Guidelines for fiberoptic bronchoscopy in adults. Am Rev Respir Dis 1361066,1987 4. Baillie J, Jowell P, Evangelou H, et a1 Use of computer graphics simulation for teaching flexible sigmoidoscopy. Endoscopy 23:126-129, 1991 5. Beer-Gabel M, Delmotte S, Muntlak L: Computerassisted training in endoscopy (C.A.T.E.): From a simulator to a learning station. Endoscopy 24S2:534538,1992 6. Britt EJ, Tasto JL, Merril GL: Assessing competence in bronchoscopy by use of a virtual reality simulator. In Proceedings of the Jubilee lob World Congress for Bronchology & loh World Congress for Bronchoesophagology, Budapest, Hungary, 1998, p 10 7. Bro-Nielsen M, Tasto JL, Cunningham RL, et al: PreOpTM Endoscopic Simulator: A PC-based immersive training system for bronchoscopy. In Westwood JD, Hoffman HM, Robb RA, et a1 (eds): Medicine Meets Virtual Reality 7 The Convergence of Physical & Informational Technologies: Options for a New Era in Healthcare. Amsterdam, Netherlands, 1999, pp 76-82 8. Cass OW Training to competence in gastrointestinal endoscopy: A plea for continuous measuring of objective end points. Endoscopy 31:751-754, 1999 9. Dawson SL, Kaufman J A The imperative for medical simulation. In Proceedings of the IEEE 86479-483, 1998

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ment of bronchoscopy skills by a bronchoscopy training simulator. Am J Respir Crit Care Med 161;3:A234,2000 26. Moroney W, Moroney B: Flight Simulation. In Garland DJ, Wise JA, Hopkins VD (eds): Human Factor Aviation Systems. Hillsdale, NJ, Lawrence, Erlbaum Associates, 1998 27. Noar M D Robotics interactive endoscopy simulation of ERCP/sphincterotomy and EGD. Endoscopy 2482:539-541,1992 28. Prakash UBS, Stubbs SE: The bronchoscopy survey: Some reflections. Chest 100:166&1677,1991 29. Prakash UBS, Offord KP, Stubbs SE Bronchoscopy in North America: The ACCP Survey. Chest 100:16681675, 1991 30. Ressler EK, Armstrong JE, Forsythe G B Military mission rehearsal. In Tekian A, McGuire C, McGaghie WC (eds): Innovative Simulations for Assessing Professional Competence. Chicago, IL, Department of Medical Education, University of Illinois Medical Center, 1999, pp 157-174 31. Rolfe JM, Staples KJ: Flight Simulation. Cambridge, England, Cambridge University Press, 1986 32. Satava RM, Jones SB: Virtual reality in medicine. In Mancall EL, Bashook PG, Dockery JL (eds): Computer-based Examinations for Board Certification. Evanston, IL, American Board of Medical Specialties, 1996, pp 121-131 33. Shannon JJ, Watts CM, Britt EJ, et a1 Teaching bronchoscopy. In Feinsilver SH, Fein AM (eds): Textbook of Bronchoscopy. Baltimore, MD, Williams & Wilkins, 1995, pp 133-153 34. Ursino M, Tasto JL, Nguyen BH, et a1 CathSim: The first low-cost intravascular catheterization simulator on a PC. In Westwood JD,Hoffman HM, Robb RA, (eds): Medicine Meets Virtual Reality 7 The Convergence of Physical & Informational Technologies: Options For a New Era in Healthcare. Amsterdam, The Netherlands, 1999, pp 360-366 35. Wachtel J: The future of nuclear power plant simulation in the United States. In Walton DG (ed): Simulation for Nuclear Reactor Technology. Cambridge, England, Cambridge University Press, 1985, p p 339349 36. Williams CB, Baillie J, Gillies DF, et al: Teaching gastrointestinal endoscopy by computer simulation: A prototype for colonoscopy and ERCP. Gastrointest Endosc 3649-54,1990

Address reprint requests to Paul A. Kvale, MD Division of Pulmonary and Critical Care Medicine 2799 West Grand Boulevard Detroit, MI 48202