Circulation 60,475 • Volume 15, No. 1 • Spring 2000

Anesthesia Simulator Training, Experience, Testing: Can It Lead to Safer Office-Based Anesthesia Care?

Michael L. Good, MD

Examples of disasters striking patients undergoing office-based anesthesia (OBA) are cited throughout this special issue of the APSF Newsletter. In general, whether in the hospital or in the OBA setting, anesthesia catastrophes or patient disasters are linked to failures to manage a patient’s airway, to unexpected respiratory events, and, either primary or secondary to hypoxemia, finally, to unexpected cardiovascular complications. Common clinical examples include inability to intubate the patient’s trachea, failure to ventilate the patient’s lung with bag and mask, acute and severe bronchospasm as might occur in an asthmatic patient or during anaphylaxis. Equally dangerous are cardiovascular collapse triggered by myocardial ischemia or drug overdose, malignant hyperthermia (MH), or a seizure, including that caused by local anesthetic toxicity. While these and other similar events are infrequent, sooner or later, these or equally dangerous things will occur in every anesthetizing location, including those in physicians’ offices where OBA is practiced.

While the essence of the critical incidents confronting the office-based surgery and anesthesia team will be similar to those encountered in hospital setting, there are important differences between the two practice environments. During a crisis in a hospital or surgery center, other physicians, nurses, and support personnel are readily available and can be summoned immediately (less than a minute) to help. Virtually every hospital anesthesia group or department has its “best” laryngoscopist who is usually called to help with an unexpectedly difficult intubation, or the local “expert” who has treated more cases of MH than anyone else. In the office-based surgery setting, the operating surgeon may have no or very little help available. Thus, the surgeon and any or all other personnel immediately available must be familiar with all emergency treatment protocols. To call 911 in case of an emergency cannot be assumed to offer life-saving help in any but the rarest of circumstances.

Can Simulation Be Helpful?

Several investigators have used simulators to assess the ability of anesthesiologists and operating room teams to diagnose and correctly treat intraoperative critical incidents.1,2,3,4,5 In general, the greater the clinical experience, the better the performance of individuals and teams in the management of a critical incident. However, virtually every study reports on worrisome errors by even the most experienced anesthesiologists and teams.6# For example, Byrne and Jones found that many experienced anesthetists recognized the need for cricothyroid puncture during a simulated airway emergency, but few were able to connect the cricothyroid cannula to the oxygen source and successfully ventilate the patient’s lungs.7

Recent studies using patient simulators also suggest that anesthesiologists do not correctly implement well-established emergency treatment protocols. For example, Kurrek and Devitt used a full-scale anesthesia simulator and created ventricular fibrillation and cardiac arrest one hour into a simulated anesthetic.8 The study subjects included university anesthesiologists, community anesthesiologists, and anesthesia residents in their last year of training. Unexpectedly, only 9% were able correctly to implement ACLS treatment protocols, with 30% committing minor deviations, and 61% demonstrating major deviations from the well-established protocols. Many subjects failed to discontinue the inhaled anesthetics, to administer epinephrine, or to use the defibrillator during the resuscitation effort. Anesthesiologists with recent ACLS training performed better than those without such training, confirming work from nearly two decades ago that demonstrated that within one year of completing an ACLS program, rescuers have difficulty recalling knowledge and performing ACLS skills.9 More recently, Chopra and colleagues used a patient simulator to both train and evaluate anesthesiologists’ ability to diagnose and treat MH. Using an empirical scoring algorithm, anesthesiologists who received simulator-based training in the diagnosis and treatment of malignant hyperthermia responded better to future simulated episodes of MH as compared to those who received their simulator-based instruction on another topic, in this study, anaphylaxis.10 Thus, we have evidence that practitioners can learn the diagnosis and management of rare complications, that is, of complications they may not have encountered in real life in their formal training. The realism of contemporary anesthesia simulations is acceptable, and continues to improve with each successive generation of patient simulator systems.

Simulator and Team Training

Aviation has pioneered the rehearsal of troubleshooting by teams required to collaborate for a successful solution of crises. Gaba and others have adapted these training techniques to anesthesiology through the development of formal Anesthesia Crisis Resource Management (ACRM) programs.11 ACRM programs are now offered regularly at many simulation centers, and specialized courses for instructors are also available. Virtually all participants rate the training programs highly. Because the surgeon, surgical assistant, anesthesiologist, and office nurse are likely to be the only ones available in the office-based operating room to respond to life-threatening critical incidents, it seems prudent that they should participate in ACRM programs as a team. A potential advantage of simulator-based training is the option of bringing the patient simulator into the physicians’ office and procedure room in which surgery will be performed. This accomplishes two important objectives. First, the surgical/anesthesia team works together, learning and practicing diagnosis and treatment protocols as a team. Each becomes familiar with the others’ concerns and roles. The simulation environment allows the crisis to be “suspended” so that clarification of roles and responsibilities can be discussed. The second advantage to conducting the simulation training in the office is that the health care team must respond to the simulated crisis using the same equipment, supplies, and pharmaceuticals that will be available to them in a real patient care crisis. If the simulation training takes place in a teaching hospital, an abundance of drugs and supplies might well make their way into the simulator training environment. Similar drugs and supplies might not be available in the office setting. For example, in training occurs in a simulation center or teaching hospital, dantrolene and the necessary volume of sterile water to mix it correctly is likely to be immediately available to treat a simulated case of malignant hyperthermia. Several years ago, we duplicated our intraoperative MH cart item by item so that we would have an exact replica in our patient simulation classroom. During our first simulated MH crisis, the anesthesiologists caring for the simulated patient found they had insufficient sterile water to mix the lyophilized dantrolene. By running the simulation with an exact replica of our operating room environment, we learned additional supplies were needed on the MH cart. Clearly, the more closely the training environment matches the actual clinical care environment, the more effective the resulting learning will be.

Office-based surgery and anesthesia teams that learn and train together using a patient simulator will be better able to diagnose and treat rare critical incidents than those without such training. Devitt and other investigators are beginning to publish needed studies on the validity and reliability of performance evaluation using patient simulators,12 but as Kapur and Steadman note, there is much work yet to be done in this area.13

Summary

Our profession has the responsibility to spare no effort to make anesthesia as safe as possible, whether in the hospital or in OBA. Simulator training can offer much to practitioners working in OBA and, by extension, to our patients.

Dr. Good, an APSF Director, is Professor of Anesthesiology at the University of Florida and Chief of Staff of the VA Hospital, Gainesville.

References

  1. Gaba DM, DeAnda A. The response of anesthesia trainees to simulated critical incidents. Anesthesia and Analgesia 1989; 68:444-451.
  2. Byrne AJ, Hilton PJ, Lunn J. Basic simulations in anaesthesia: A pilot study of the ACCESS system. Anaesthesia 1994; 49:376-381
  3. DeAnda A, Gaba DM. Role of experience in the response to simulated critical incidents. Anesthesia and Analgesia 1991; 72:308-
  4. DeAnda A, Gaba DM. Unplanned incidents during comprehensive anaesthesia simulation. Anesthesia and Analgesia 1990; 71:77-82
  5. Chopra V, Bovill JG, Spierdjijk J, Brand R. Does training on an anaesthesia simulator lead to an improvement in performance? British Journal of Anaesthesia 1994; 73:293-297.
  6. Byrne AJ, Jones JG. Responses to simulated anaesthetic emergencies by anaesthetists with different durations of clinical experience. British Journal of Anaesthesia 1997; 78:553-556
  7. Byrne AJ, Jones JG. Responses to simulated anaesthetic emergencies by anaesthetists with different durations of clinical experience. British Journal of Anaesthesia 1997; 78:553-556
  8. Kurrek MM, Devitt JH, Cohen M. Cardiac arrest in the OR: How are our ACLS skills? Can J Anaesth 45:130-32,
  9. Lowenstein SR, Hansbrough JF, Libby LS, Hill DM, Mountain RD, Scoggin CH. Cardiopulmonary resuscitation by medical and surgical house-officers. Lancet 1981; 2:679-81.
  10. Chopra V, Gesink BJ, deJong J, et al. Does training on an anaesthesia simulator lead to improvement in performance? Br J Anaesth 1994; 73:293-7.
  11. Gaba DM, Fish KJ, Howard SK: Crisis Management in Anesthesiology. Churchill Livingstone, New York, 1994
  12. Devitt JH, Kurrek MM, Cohen MM, et al. Testing internal consistency and construct validity during evaluation of performance in an anesthesia simulator. Anesth Analg 1998; 86:1160-4.
  13. Kapur PA, Steadman RH. Patient simulator competence testing: ready for takeoff? Anesth Analg 1998; 86:1157-9.