ACI-TIPI Acute Cardiac Ischemia Time-Insensitive Predictive Instrument GE Medical Systems Information Technologies (GEMS IT) went to the original inventor, the trial coordinator, and a physician who participated in the ACI-TIPI Trial for some expert discussion. GE Medical Systems proudly incorporates Marquette’s history in electrocardiography to ensure the highest quality and accuracy. Ask the Experts Harry P. Selker, M.D. Tom Aufderheide, M.D. Joni Beshansky, R.N., M.P.H. What gave you the initial idea for a predictive instrument for acute cardiac ischemia? As a clinician in the emergency department, I well knew how hard it was, among the many patients presenting with chest pain or other symptoms suggestive of acute cardiac ischemia, to decide whom I should admit and whom I could safely send home. I saw the idea of a predictive instrument that could give an independent objective assessment of the patient’s true probability of truly having acute ischemia (i.e., either acute myocardial infarction or unstable angina pectoris, for which we hospitalize patients) as being a potentially very helpful thing. DR. SELKER: How does ACI-TIPI address the need for “real-time”and retrospective interpretation of data? The ability to make a decision correctly is important, and to make it quickly is also important. So, we think that in general, when used in a real-time clinical setting, ACI-TIPI may help the physician make more informed decisions. And that’s very good. But, why do we call it the “time-insensitive” predictive instrument (TIPI)? Well, we made it so it would be “insensitive” to when in time you use it, whether for real-time care or if used later, retrospectively, after the fact to judge the appropriateness and quality of care. This demonstrated validity for both real-time and retrospective use is unique to TIPIs, and has proven to be an attractive way to get all members of the healthcare community to work together to improve care. DR. SELKER: The ACI-TIPI algorithm was developed by Harry P. Selker, MD, Chief of Clinical Care Research and Director of the Center for Cardiovascular Health Services Research at New England Medical Center. Dr. Selker is also Professor of Medicine at Tufts University. Dr. Selker has pioneered research in hospitals and emergency departments to develop methods to improve cardiac care, including development of cardiac predictive instruments as decision aids such as ACI-TIPI. ACI-TIPI underwent extensive clinical testing in a federally-funded clinical trial led by Dr. Selker that included 10,689 patients at 10 hospitals nationwide. ACI-TIPI ASK THE EXPERTS randomized study, the data demonstrated that ACI-TIPI did improve triage decisions when it was available to the clinician. In general, the physicians did not want to recognize that a computerized instrument was better than their independent clinical judgment. However, when they realized that ACI-TIPI information supplemented, not replaced, physician judgement, and when they learned the results of the study, physician opinion dramatically changed. What about the effect of individual patient circumstances? How did that impact your findings with respect to ACI-TIPI? DR. AUFDERHEIDE: ACI-TIPI doesn’t restrict the physician’s Dr. Tom Aufderheide was one of the site co-investigators, at the Medical College of Wisconsin, where he is Associate Professor of Emergency Medicine. Dr. Aufderheide is board certified in internal medicine and emergency medicine. He has published extensively in the field of emergency cardiac care. work-up or approach to patient care. Physicians can implement a comprehensive or succinct evaluation, as they feel appropriate for any individual patient. In addition, they can incorporate the ACI-TIPI score into that clinical decision-making process. ACI-TIPI, then, is applicable to a wide range of patients and can be incorporated into any approach to patient care that the physician feels is appropriate for that individual. The ACI-TIPI "score" reflects the percentage of probability that the patient has acute cardiac ischemia. How should physicians interpret that score? A good analogy for the score is the weather report. It will tell you there’s a 30 per cent, 50 per cent, or 90 per cent probability of rain, and that helps you make a better decision. Of course, it depends on how the sky looks and how far you’re walking – they affect your decision. For example, if the weather forecaster says there’s only a 30 per cent chance of rain, but it’s raining cats and dogs outside, you’ll carry an umbrella. It’s obvious. You don’t need a weather forecast to help you. On the other hand, if it's blue, sunny skies and they report a 20 or 30 per cent chance, you probably won’t bring an umbrella. It’s when it’s overcast, that the prediction is most useful. Well, it’s that way for a patient, too, with the probability of acute ischemia. It’s for the “overcast” patient that ACI-TIPI is most helpful in your triage decision making. DR. SELKER: How was the trial conducted? This was a prospective, randomized, controlled clinical trial. The ACI-TIPI was not available to the treating clinician 50 percent of the time. The primary study end point was accuracy of triage decisions with and without the availability of ACI-TIPI. DR. AUFDERHEIDE: Did you have any pre-conceived ideas about ACI-TIPI before you participated in the study? DR. AUFDERHEIDE: I always strive to maintain an open mind until all of the data has been acquired and analyzed. If there was any collective bias at our study site, it was that ACI-TIPI would not significantly improve accuracy of triage decisions. What did you discover with regard to that particular bias? Prior to the end of the trial, we asked our local physicians whether they thought the ACI-TIPI helped their triage decisions. The consensus opinion of the physicians was that ACI-TIPI did not improve their clinical judgment. However, following completion of this DR. AUFDERHEIDE: Is ACI-TIPI validated for various ethnic groups? In that national trial, we had excellent ethnic diversity, including Asian, Caucasian, Hispanic and Black patients, and the results showed that ACI-TIPI was effective across all those groups. DR. SELKER: One of the variables that the ACI-TIPI algorithm takes into account is whether the patient has a chief or secondary complaint of chest pain. How do you define "chest pain" for the purposes of using ACI-TIPI? The definition of “chest pain” is discomfort consistent with an anginal equivalent syndrome. This could be any combination of pain, pressure, tightness, squeezing or shortness of breath. The discomfort may be located in the chest, upper abdomen, neck, jaw or left arm. If the discomfort is the primary symptom that caused the patient to seek medical attention, it is considered a chief complaint. Otherwise, it is considered a secondary complaint. When using ACI-TIPI, it is important to adequately train personnel to accurately assess whether the symptom complex potentially represents an anginal equivalent syndrome, and whether it is a chief or secondary complaint. The treating physician, in my opinion, has the most information and expertise to accurately make this judgement. DR. AUFDERHEIDE: The Project Director for the national ACI-TIPI Trial, Joni Beshansky, RN, MPH, has helped hospitals’ emergency departments throughout the country institute use of ACI-TIPI. She is a clinical researcher with Dr. Selker at the Center for Cardiovascular Health Services Research at New England Medical Center and is Assistant Professor of Medicine at Tufts University School of Medicine. JONI BESHANSKY: Potential users of ACI-TIPI might think that for the ACI-TIPI chest pain question, the patient must have chest pain at the time the electrocardiogram is being done. That is not the case. We just need to know whether chest pain was the primary symptom and the main reason for coming to the emergency department. The confusion might arise about the distinction between primary complaint and secondary complaint. If the users aren’t sure, they should consider it “primary.” This default will lead to a slightly higher number which is safer than having a lower value. The fortunate thing is that the most powerful variables for ACI-TIPI are the data from the ECG. So chest pain is important, but the ECG really tells the story. DR. SELKER: ACI-TIPI ACTUAL CASES Case 1: 41-Year-Old Male ACI-TIPI Score: 96% DR. AUFDERHEIDE: For patients with obvious hyper-acute ST segment elevation MI, the ACI-TIPI score may be less frequently useful. The physician should immediately recognize the electrocardiographic diagnosis without assistance from ACI-TIPI. Conversely, it may be immensely helpful if the relatively obvious diagnosis remains unrecognized until the high ACI-TIPI score causes the physician to more carefully evaluate the ECG. Case 2: 50-Year-Old Male ACI-TIPI Score: 25% DR. AUFDERHEIDE: This example identifies that “gray” area where ACI-TIPI demonstrates significant benefit. Such patients are very difficult to evaluate, in part, because of an abnormal, but non-diagnostic electrocardiogram. An ACI-TIPI score in these circumstances can assist the physician is making sound triage decisions. Case 3: 50-Year-Old Male ACI-TIPI Score: 5% DR. AUFDERHEIDE: One of the major benefits of ACI-TIPI is independent confirmation of a low risk for ischemia. In fact, use of ACI-TIPI, with physician interpretation, is associated with reduced hospitalization among emergency department patients without acute cardiac ischemia. ACI-TIPI can independently confirm the physician’s suspicion of low risk and appropriately allow the non-ischemic patient to be safely discharged home. Do you think physicians will embrace ACI-TIPI? Of the many different physicians to whom I have presented, all were more than pleased to use it once they understood the operational simplicity of the software as implemented in the electrocardiograph. They needed to understand that ACI-TIPI was not telling them “what to do” with their patients, but that it was simply another piece of information provided to them to assist in their own decision-making process JONI BESHANSKY: DR. AUFDERHEIDE: I view ACI-TIPI as an effective, user- friendly addition to the diagnostic evaluation of one of the most difficult patient populations in emergency medicine. If physicians can recognize this effective tool for what it is (valuable supplemental information, not replacing physician judgement), it is likely to be widely applied. In summary, what are the most important benefits of ACI-TIPI to the physician? What are some specific situations where ACI-TIPI would be particularly valuable? DR. SELKER: The ACI-TIPI, along with physician interpretation, has now been shown to improve the accuracy and speed of emergency department triage. Also, it can act as part of an emergency department risk-management error-reduction program to help reduce the likelihood of patients being mistakenly sent home with acute cardiac ischemia, which of course, could also reduce malpractice costs. Finally, because, as a “TIPI,” the ACI-TIPI is valid for both real-time and retrospective use, it can promote the coming together of clinicians, hospitals, and others in the healthcare system to improve emergency cardiac care by their all using the same, clinically valid, tool. DR. AUFDERHEIDE: Another potential use of ACI-TIPI is in determining eligibility for chest pain observation unit evaluation. Many chest pain observation units in the United States target relatively low risk patients with a less than 15 percent chance of ischemia. The ACI-TIPI risk stratifies patients with chest pain and has the potential to assist emergency physicians in more appropriately utilizing chest pain observation unit services. GE Medical Systems Information Technologies General Electric Company reserves the right to make changes in specifications and features shown herein, or discontinue the product described at any time without notice or obligation. 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