Papers in Press. Published December 23, 2014 as doi:10.1373/clinchem.2014.234310 The latest version is at http://hwmaint.clinchem.org/cgi/doi/10.1373/clinchem.2014.234310 Clinical Chemistry 61:3 000 – 000 (2015)
Evidence-based Medicine and Test Utilization
Electronic Medical Record–Based Performance Improvement Project to Document and Reduce Excessive Cardiac Troponin Testing Sara A. Love,1 Zeke J. McKinney,2,3 Yader Sandoval,4 Stephen W. Smith,5,6 Rebecca Kohler,2 MaryAnn M. Murakami,1 and Fred S. Apple1,7*
BACKGROUND: We assessed the utilization rationale behind provider ordering of cardiac troponin I (cTnI) testing for the diagnosis of myocardial infarction after implementation of a hospital-wide serial order protocol.
CONCLUSIONS: Providers largely ignored the BPA that warned of potential overutilization of cTnI testing independent of diagnosis, including ACS.
METHODS: During 2 months in 2013, any request for additional cTnI testing within 30 days of the initial serial cTnI order prompted an electronic health record best practice alert (BPA), which included clinical decision support that could be bypassed by giving a clinical indication. cTnI orders were not limited (timing, number), and upon BPA, trigger data was collected for clinical indications and actions, patient stay (duration, location), International Classification of Diseases, Revision 9 diagnosis, cTnI orders, and timing of cTnI measurements. RESULTS: The BPA was triggered 1477 times by 423 providers who cared for 702 patients. There were a mean of 3.6 cTnI results per patient, 2.1 BPAs per patient, and 1.2 visits per patient. Providers (42% of whom were residents) acknowledged and overrode the BPA 97% of the time. In response to the BPA, 65% of providers selected a prepared rationale: 64% acute coronary syndrome/ST-elevation myocardial infarction/non–ST-elevation myocardial infarction; 30% demand ischemia; and 6% non-ACS myocardial necrosis. Of the remaining 35% of providers, 71% listed no rationale for their additional cTnI orders. Of patients with a BPA, 93% had non–ACS-related primary International Classification of Diseases, Revision 9 diagnosis, and 58% of the time, patients’ cTnI results never increased during their stay. In 53% of cases, BPAs were generated by a request for an additional cTnI series when ⬍2 results were available.
According to the Agency for Healthcare Research and Quality Healthcare Cost and Utilization Project, the mean cost of hospital stays in 2011 was $10 000, and although inpatient length of stay has shortened, the perday costs have increased ($2000 in 2009 vs $1400 in 1997 for all stays) (1 ). As hospital budgets tighten and reimbursements diminish, costs and value in health care are becoming major considerations for patients, providers, and hospitals. One strategy to improve the value of health care is the Choosing Wisely initiative (2 ). It suggests potential areas for reducing redundant and unnecessary laboratory testing within evidence-based practice, without compromising patient care. A major component of improving healthcare value is overall resource and utilization management by reducing unnecessary and ineffective services (3 ). If increased value is to be achieved, education on redundancy and utilization for both laboratory testing and treatments is necessary at the level of institutions, providers, and patients. Recently, the American College of Cardiology and American Heart Association highlighted the need for incorporating resource and value considerations during the generation of guidelines as well as during the evaluation of relevant evidencebased test/treatment recommendations for a specific patient (4 ). Cardiac troponin is a biomarker of myocardial injury but does not indicate any specific pathophysiology. The clinical context is critical to understanding and properly interpreting increased cardiac troponin concentrations. Best practices remain a challenge for cardiac troponin utilization with respect to timing and duration
Departments of 1 Laboratory Medicine and Pathology, 2 Clinical Informatics, 4 Medicine, Division of Cardiology, and 5 Emergency Medicine, Hennepin County Medical Center, Minneapolis, MN; Departments of 3 Occupational and Environmental Medicine, 6 Emergency Medicine, and 7 Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN.
* Address correspondence to this author at: Clinical Laboratories #812 701 Park Avenue, Hennepin County Medical Center, Minneapolis, MN 55415. Fax 612-904-4229; e-mail [email protected]. Received October 3, 2014; accepted December 1, 2014. Previously published online at DOI: 10.1373/clinchem.2014.234310
© 2014 American Association for Clinical Chemistry
1
Copyright (C) 2014 by The American Association for Clinical Chemistry
of orders for the diagnosis or exclusion of acute myocardial infarction (AMI)8 (5–15 ). In 2013, our medical center adopted a single, timed, preset order for all cardiac troponin I (cTnI) testing. This order provides 4 cTnI results, at time of presentation (0 h) and at 3-h intervals subsequent to the initial draw (3, 6, and 9 h). This serial order set facilitates cTnI testing in several ways. First, it eliminates the need for multiple, separate orders by multiple providers, thus avoiding delays from separate electronic order entry by busy clinical providers. Second, the orders follow the patient between medical units within the hospital, lessening the likelihood of a missed blood draw during patient transfer between departments and providers. Third, in very low-risk patients for whom the emergency department physician is discharging the patient after ⬍4 troponin values, the remaining orders are automatically cancelled. The objectives of the current study were 2-fold. Our primary goal was to identify overutilization of cTnI testing on the basis of additional testing after a clinical diagnosis was determined. Our secondary goal was to identify which providers were ordering additional cTnI testing and in what clinical contexts. To attempt to provide utilization guidance in the cTnI ordering process and examine the rationale for ordering, a pop-up alert was implemented in the electronic health record (EHR), warning the ordering provider who attempted to place further cTnI orders after myocardial injury had already been diagnosed or excluded. METHODS
The changes to the process of cTnI ordering were all implemented in our institution’s EHR (Epic Systems Corp.) and went live (became available to clinicians) on August 6, 2013. Our EHR’s version at the time of implementation and analysis was Epic 2012. LIMITING cTnI ORDERING FREQUENCY AND NUMBER OF TESTS PER ORDER
We modified the existing order for cTnI so that (a) it could not be ordered more frequently than every 3 h and (b) it defaulted to 4 tests per order set. However, clinicians maintained the authority to change this number during the ordering process, either by manually changing the default or through a subsequent order. These changes were a divergence from the previous user-defined individual orders, which had varied in frequency or occurrences before initiation of this project, and thus comprised a default order series of 4 cTnI tests occurring
8
Nonstandard abbreviations: AMI, acute myocardial infarction; cTnI, cardiac troponin I; EHR, electronic health record; URL, upper reference limit; BPA, best practice alert; ACS, acute coronary syndrome; STEMI, ST-elevation MI; NSTEMI, non–ST-elevation MI; ICD-9, International Classification of Diseases, Revision 9.
2
Clinical Chemistry 61:3 (2015)
every 3 h. These changes were seamless in the provider workflow to the extent that the process of cTnI ordering, including the appearance of the cTnI order, was in every other regard unchanged. Thus, providers would be able to discontinue remaining orders of a series if they were not clinically indicated [e.g., the first 2 cTnI values were ⬍99th percentile upper reference limit (URL) or a rising/ falling cTnI pattern was noted above the URL in the clinical setting to rule in an AMI]. IMPLEMENTATION OF cTnI COMPUTERIZED PHYSICIAN ORDER ENTRY ALERTS
We implemented a new EHR alert such that if a patient had ⱖ1 existing cTnI result in the past 30 days, any subsequent cTnI order would immediately trigger a best practice alert (BPA) pop-up window with the following text (Fig. 1A): “This patient has already had serial troponins ordered in the past 30 days. Troponins are a surrogate of myocardial injury and are often overutilized inappropriately. What is the suspected etiology of myocardial injury prompting a repeat of the troponin I series? If you choose ‘other’ below, please enter a comment using the ‘Acknowledge reason’ field.” In addition to the clinical decision support of the above text, the patient’s most recent cTnI values were displayed up to a maximum of the 5 most recent. The BPA required the user to select 1 of a list of clinical indications (Table 1, left column) for a repeat cTnI order before the BPA could be bypassed (i.e., a hard stop). Despite the requirement for an indication within the build of the BPA, workarounds for the BPA were discovered that could allow users to continue without specifying an indication, thus negating the intended BPA implementation as a hard stop. BPA indications were selected via single-click buttons immediately below the clinical decision support text. Free-text comments for the indication (intended particularly for the indication of “other”) were entered via a text field opened by a button adjacent to the selection of the indication, as displayed in Fig. 1A. DATA COLLECTION AND ANALYSIS
We acquired data through standard query language queries on our EHR’s extracted relational database (Epic Clarity). The primary cTnI orders dataset included all cTnI orders identified retrospectively that occurred during the study period. Critical primary order dataset variables are listed in Table 2. The primary cTnI alerting dataset included all instances of the BPA trigger during the study period, with cTnI values collected for the duration of the BPA-associated encounter. Critical alerting dataset variables are listed in Table 3. Data were analyzed in Microsoft Excel. Testing for cTnI was performed with EDTA plasma by use of the Architect i1000SR and i2000SR instru-
Cardiac Troponin Test Overutilization
Fig. 1. Findings derived from EHR BPA. (A), Alert text indicating possible overutilization, with ≤5 most recent cTnI results shown at time of BPA. (B), Number and percentage of users acknowledging the BPA and orders placed. (C), Primary providers observing BPAs, by clinical role. PGY, postgraduate year; PA, physician assistant.
ments (Abbott Laboratories), with a 99th percentile URL of 0.025 g/L (16 ). In accordance with standard hospital laboratory practices, duplicate orders within 2 h were combined at the time of collection to reduce the number of needle sticks for the patient (i.e., cTnI series ordered at
Table 2. Order data set variables. cTnI order data set variables Patient status (e.g., inpatient, outpatient, emergency)
Table 1. cTnI repeat-order BPA indications, as listed in BPA.
Order status (e.g., canceled) Ordering user Authorizing user (e.g. cosigned orders)
Possible alert indication
Selected, %
Patient location
ACS (STEMI or NSTEMI)
36
Ordering department
Demand ischemia
17
Order date/time
Non-ACS myocardial necrosis
3
Number of occurrences ordered
35
Number of occurrences released
None given
71
Number of occurrences completed
Chest pain
5
Primary hospital billed diagnosis
Retiming or ACS or trauma
2
Secondary hospital billed diagnosis
Other (free text entry)
Clinical Chemistry 61:3 (2015) 3
Table 3. BPA data set variables.
Table 5. Characteristics of BPA-associated patients (n = 702).
cTnI BPA data set variables Characteristic
Date/time user acted on BPA Number of instances of BPA for the same patient
Male, n
Selected indication
Female, n
Indication comments
Age, years, mean (range)
Date/time of order triggering the BPA
BPA frequency and timing, mean (range) cTnI tests per patient
User that triggered the BPA
1200 and 1230 were combined into a single series). This type of laboratory practice results in a significantly lower number of completed results then would be anticipated on the basis of the number of requests, which may underestimate the magnitude of laboratory testing. Results PROVIDER AND PATIENT DEMOGRAPHICS
The BPA was triggered 1477 times during the 2-month alert period (Fig. 1B). The BPAs occurred during 833 separate patient visits by 423 unique providers delivering care to 702 patients (summarized by role in Fig. 1C). A summary of the findings and demographics for BPAtriggering providers and associated patients are presented in Tables 4 and 5, respectively.
Value
404 298 56 (3–96) 3.6 (0–21)
Encounters per patient
1.2 (1–6)
BPAs per encounter
2.1 (0–12)
ICD-9 code ACS-related Patients, n
52
BPAs, n
106
cTnI results, n
316
Initially increased cTnI, %
59
cTnI became increased, %
23
cTnI never increased, %
17
Non–ACS-related Patients, n
650
BPAs, n
1368
cTnI results, n
2736
Initially increased cTnI, %
29
cTnI became increased, %
12
cTnI never increased, %
58
RATIONALE FOR ADDITIONAL ORDERING AND PROVIDER ACTION AFTER BPA
Table 4. EHR BPA-associated hospital unit and generating providers (n = 423). Provider or unit
BPAs, n (%)
Provider by training Resident
181 (42)
PGY1a
71 (40)
PGY2
48 (27)
PGY3
49 (27)
PGY4–6 Nurse
13 (7.2) 169 (40)
Attending
41 (9.7)
Other
32 (7.5)
Hospital unit
a
4
Cardiac-renal
482 (33)
Short-term observation
224 (15)
Emergency department
107 (7.2)
PGY, postgraduate year.
Clinical Chemistry 61:3 (2015)
When providers saw the BPA, they overwhelmingly (n ⫽ 1440, 97%) acknowledged and overrode the BPA (Fig. 1A). For overridden BPAs, providers selected from the prompted list 929 times (65%), selecting acute coronary syndrome (ACS) concern [ST-elevation MI (STEMI) and non–ST-elevation MI (NSTEMI)], n ⫽ 519 (35%); demand ischemia, n ⫽ 249 (17%); and non-ACS myocardial necrosis, n ⫽ 50 (3%). Of the providers electing to describe the clinical indication by free text entry, 71% gave no indication. Of the 29% of providers that described the clinical indication, the 5 most common answers were related to chest pain (n ⫽ 23), retiming (n ⫽ 11), ACS (n ⫽ 10), trauma (n ⫽ 7), or emergency department visit (n ⫽ 6). TROPONIN RESULTS AND ALERTS: TIMING AND INCREASES
The generated BPAs were associated with 3045 completed cTnI results. For each of the 833 patient visits, a mean of 3.6 cTnI results were completed (95% CI 3.6 – 3.8, range 0 –21). A mean of 1.8 cTnI results were available before a BPA and 2.5 cTnI results after a BPA. Be-
Cardiac Troponin Test Overutilization
Fig. 2. Box-and-whisker plot of number of cTnI results per patient, in ACS and NON-ACS (A) patients and number of cTnI results per patient, by BPA alerting primary provider’s clinical role (B). PGY, postgraduate year; RN, nurse; MD, doctor; PA, physician assistant.
fore a single cTnI result was available, 347 (23%) BPAs were triggered, and almost 800 BPAs were generated when ⱕ1 results were available. In other words, providers were ordering new sets when the first order set had only begun to be carried out. The first cTnI value was increased (above the 99th percentage reference) in 238 patient visits (30%), increasing to 359 (43%) over the duration of cTnI testing. Of those patients with initially increased cTnI values, 205 (86%) remained increased for the duration of measured cTnI results and, of those 205, 0 –17 additional cTnI results were reported after the first BPA, with 77% having 1– 4 additional results. ACS ENCOUNTERS
According to associated International Classification of Diseases, Revision 9 (ICD-9) codes for the BPA-related encounters, 52 patients had an ACS diagnosis for STEMI (n ⫽ 19), NSTEMI (n ⫽ 9), or unstable angina (n ⫽ 24). These patients had a mean of 6 (95% CI 5.3–7.0, range 3–16) cTnI results, as shown in Fig. 2A. Of these patients, 59% presented with initially increased cTnI values, of which 86% remained increased throughout. Of those with an initially increased cTnI, 66% had ⱖ5 cTnI results during admission. Of those patients presenting without an initial increase, 23% increased over serial measurements and 61% had ⱖ5 cTnI results during their admission. NON-ACS ENCOUNTERS
The 650 patients who did not have a final ACS-related diagnosis were associated with 92% of BPAs. They had a mean of 4 (95% CI 3.3– 4.6, range 0 –21) cTnI results, as shown in Fig. 2B. Of these patients, 29% presented with an initially increased cTnI value, of which 80% remained increased. Of those without an initial increase, 12% became increased and 58% did not have concentrations above the URL during their hospitalization. Of the non-
ACS encounters within this cohort, 21% had ⱖ5 cTnI results during admission. Discussion Our findings are interesting in several ways. First, we observed that, at our institution, cTnI testing is overutilized in the clinical care of patients presenting to rule in or rule out AMI. Second, providers, even when notified that their cTnI testing is likely excessive, largely overrode visual BPAs to modify their ordering practices. Third, the largest absolute number of inappropriate cTnI orders was by residents, reflective of the overall ordering pattern within our institution, despite supervised training with faculty, in moderate- to high-risk patients (telemetry unit) and patients with a non-MI diagnosis. Our current findings validated our hypothesis that providers overutilize cTnI testing. The 3045 BPA-related cTnI results were roughly 50% of the total hospital’s 6025 completed cTnI results during the alert period. Our routine laboratory practice is to combine or cancel multiple/duplicate orders, and when possible to minimize patient blood draws. This standard practice prevents a substantial number of inefficient orders from being completed, which for the purpose of the current study underestimates the extent of cardiac troponin overutilization. In theory, if all of the additional order sets requested were completed and no duplicate orders were combined, approximately 7000 additional cTnI results would have been reported. According to the Third Universal Definition of Myocardial Infarction (5 ), a clinical decision to rule in or rule out AMI would be possible by the fourth cTnI result and, without a change in clinical context, additional measurements would be deemed unnecesClinical Chemistry 61:3 (2015) 5
sary for diagnostic purposes. Without adjudicating each of these cases, the level of overutilization is not precisely known. If one considers that each evaluation for a given encounter would require 4 cTnI results to rule in or rule out AMI, the most straightforward set of patients would be those with a diagnosis of STEMI. In that subset, there was a mean of 6 (95% CI 5.3–7.0) cTnI results. This would indicate that within this alerting cohort, a conservative estimate of 32% of the cTnI results were unnecessary and therefore cTnI was overutilized. This volume of wasteful testing is a considerable financial burden, estimated to be hundreds of thousands of dollars a year, affecting both patient charges and hospital direct costs, without adding value to patient care (14 –16 ). On the basis of the evidencebased Third Universal Definition of Myocardial Infarction guidelines, and in light of the fact that 53% of BPAs were generated before there were 2 cTnI results, a substantial number of providers were requesting additional cTnI testing without having sufficient data to provide a clear picture of rising/falling pattern within the cTnI results. As cTnI ordering in the current study was not statistically different from that of the 2 months after the alert period (data not shown), the BPA did not decrease the overutilization of cTnI within the institution. Thus, our primary objective to reduce overutilization of cTnI was not successful. Given the overwhelming response of providers to acknowledge and override the BPA within the EHR, this was not an effective tool to reduce test ordering. One interpretation of this would be that ordering providers found this BPA similarly irritating to the pop-up windows found while casually browsing the internet, which most individuals attempt to close as quickly as possible. Our secondary objective was to determine who was ordering additional cTnI testing and for which patients. As shown in Fig. 1C and Tables 4 and 5, ordering providers with BPAs were predominantly within their first 3 years of residency, and patients were ultimately not found to have an ACS-related diagnosis. Because ours is a teaching hospital, the majority of any laboratory test ordering, including cTnI, is placed by residents. BPA generation was predominantly for patients from the cardiac-renal unit, accounting for 33% of all BPAs and more than twice the rate compared with the short-term observation unit, where most suspected ACS patients from the emergency department go for continued observation during the remainder of the time required to rule in or rule out ACS. For the patients in the cardiac-renal unit, the top 2 categories of ICD-9 diagnoses were related to heart failure and renal disease. Our findings highlight the important role that the clinical scenario plays in 6
Clinical Chemistry 61:3 (2015)
proper utilization at the time of cTnI ordering. With the advent of high-sensitivity cardiac troponin assays, this issue will become even more critical as we begin to more accurately measure lower concentrations of cardiac troponin (5, 8, 17–20 ). When patients had ACS, providers did no better at utilizing cTnI, since monitoring of cTnI continued beyond those tests needed for the ACS diagnosis. Within our alerting cohort, we found there were 102 BPAs for the 52 patients with an ACS diagnosis, with ⬎60% having ⱖ5 cTnI results. These patients had 315 results collectively, with a mean of 6 results/patient, which is similar to a recent study in our hospital examining 100 consecutive cardiac-renal unit patients (21 ). Within that study, in which all included patients were adjudicated by a cardiologist, 48% of the cTnI results occurred after the ACS diagnosis had already been made. Although that study preceded our BPA period, and we did not have a cardiologist adjudicate patient results, our alert data do suggest that a similar level of overutilization continued during the alert period within our hospital. The following limitations for our study are noted. First, the implementation of the BPA was incomplete, since it allowed users to dismiss it without providing a rationale for their requests. Second, because the BPA was implemented at the same time as a uniform cTnI order, no direct comparison could be made to utilization before its implementation. Potential corrective actions that require further study to decrease overtesting could include (a) implementing a true hard stop (one that cannot be overridden) in our EHR/Epic order system to prevent overuse at order entry, (b) continued hospital-wide education using conferences and emails with evidence guideline literature on the proper use of cTnI testing, and (c) meetings with the Office of the Medical Director’s Quality Assurance staff to engage division chiefs to support reducing orders during non–ACS-related evaluations. In conclusion, our data show that (a) cTnI testing for diagnosis and exclusion of AMI is overutilized, (b) visual alerts did not result in a decrease in excessive cTnI orders by providers, even after a diagnosis was determined, (c) the largest number of ignored alerts was in non-ACS patients, and (d) even providers treating patients already diagnosed with AMI practiced excessive cTnI ordering. More appropriate cTnI utilization could provide substantial financial savings without compromising patient care. Effective means of encouraging appropriate utilization need to be explored.
Author Contributions: All authors confirmed they have contributed to the intellectual content of this paper and have met the following 3 requirements: (a) significant contributions to the conception and design,
Cardiac Troponin Test Overutilization
acquisition of data, or analysis and interpretation of data; (b) drafting or revising the article for intellectual content; and (c) final approval of the published article. Authors’ Disclosures or Potential Conflicts of Interest: Upon manuscript submission, all authors completed the author disclosure form. Disclosures and/or potential conflicts of interest: Employment or Leadership: F.S. Apple, Clinical Chemistry, AACC. Consultant or Advisory Role: Y. Sandoval, Roche Diagnostics; F.S. Apple, Instrumentation Laboratory, Phillips.
Stock Ownership: None declared. Honoraria: None declared. Research Funding: F.S. Apple, nonsalaried research funding from numerous manufacturers of cardiac troponin assays through the Minneapolis Medical Research Foundation of Hennepin County Medical Center. Expert Testimony: None declared. Patents: None declared. Role of Sponsor: No sponsor was declared. Acknowledgments:
References 1. Healthcare Cost and Utilization Project (HCUP) statistical briefs. http://www.hcup-us.ahrq.gov/reports/ statbriefs/sbtopic.jsp (Accessed May 2014). 2. Choosing Wisely: an initiative of the American Board of Internal Medicine (ABIM) Foundation. http://www. choosingwisely.org (Accessed May 2014). 3. Institute of Medicine. The healthcare imperative: lowering costs and improving outcomes. Washington, DC: The National Academies Press; 2010. 4. Anderson J, Heidenrieich P, Barnett P, Creager M, Fonarow G, Gibbons R, et al. ACC/AHA statement on cost/value methodology in clinical practice guidelines and performance measures: a report of the American College of Cardiology/American Heart Association Task Force on Performance Measures and Task Force on Practice Guidelines. J Am Coll Cardiol 2014;63:2304 –22. 5. Thygesen K, Alpert J, Jaffe A, Simoons M, Chaitman B, White H, et al. Third universal definition of myocardial infarction. J Am Coll Cardiol 2012;60:1581–98. 6. Twerenbold R, Jaffe A, Reichlin T, Reiter M, Mueller C. High-sensitive troponin T measurements: what do we gain and what are the challenges? Eur Heart J 2012;33: 579 – 86. 7. Cullen L, Parsonage W, Greenslade, Lamanna A, Hammett C, Than M, et al. Delta troponin for the early diagnosis of AMI in emergency patients with chest pain. Int J Cardiol 2013;168:2602– 8. 8. Storrow A, Lardaro T, Alexander P, Apple FS. How low
can we go? The high-sensitivity cardiac troponin debate. Ann Emerg Med 2013;62:580 –3. 9. Koerbin G, Tate J, Potter J, Cavanaugh J, Glasgow N, Hickman P. Characterization of a highly sensitive troponin I assay and its application to a cardio-healthy population. Clin Chem Lab Med 2012;50:871– 8. 10. Wu A, Bolger A, Hollander J. Growing pains with the use of high-sensitivity cardiac troponin assays. J Am Coll Cardiol 2013;62:1250 –1. 11. Anderson J, Adams C, Antman E, Bridges C, Califf R, Casey D, et al. 2011 ACCF/AHA focused update incorporated into the ACC/AHA 2007 Guidelines for the Management of Patients With Unstable Angina/Non–STElevation Myocardial Infarction. Circulation 2011;123: e426 –579. 12. Thygesen K, Mair J, Giannitsis E, Mueller C, Lindhal B, Blackenberg S, et al. How to use high-sensitivity cardiac troponins in acute cardiac care. Eur Heart J 2012;33: 2252–7. 13. Newby L, Jesse R, Babb J, Christenson R, De Fer T, Diamond G, et al. ACCF 2012 expert consensus document on practical clinical considerations in the interpretation of troponin elevations. J Am Coll Cardiol 2012;60: 2427– 63. 14. Larochelle M, Knight A, Pantle H. Reducing excess cardiac biomarker testing at an academic medical center. J Gen Intern Med 2014;29:1468 –74. 15. Scorgie R, Nicholls G, Jones P. Association between an educational intervention and a reduction in inappropri-
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Clinical Chemistry 61:3 (2015) 7
Evidence-based Medicine and Test Utilization
Electronic Medical Record–Based Performance Improvement Project to Document and Reduce Excessive Cardiac Troponin Testing Sara A. Love,1 Zeke J. McKinney,2,3 Yader Sandoval,4 Stephen W. Smith,5,6 Rebecca Kohler,2 MaryAnn M. Murakami,1 and Fred S. Apple1,7*
BACKGROUND: We assessed the utilization rationale behind provider ordering of cardiac troponin I (cTnI) testing for the diagnosis of myocardial infarction after implementation of a hospital-wide serial order protocol.
CONCLUSIONS: Providers largely ignored the BPA that warned of potential overutilization of cTnI testing independent of diagnosis, including ACS.
METHODS: During 2 months in 2013, any request for additional cTnI testing within 30 days of the initial serial cTnI order prompted an electronic health record best practice alert (BPA), which included clinical decision support that could be bypassed by giving a clinical indication. cTnI orders were not limited (timing, number), and upon BPA, trigger data was collected for clinical indications and actions, patient stay (duration, location), International Classification of Diseases, Revision 9 diagnosis, cTnI orders, and timing of cTnI measurements. RESULTS: The BPA was triggered 1477 times by 423 providers who cared for 702 patients. There were a mean of 3.6 cTnI results per patient, 2.1 BPAs per patient, and 1.2 visits per patient. Providers (42% of whom were residents) acknowledged and overrode the BPA 97% of the time. In response to the BPA, 65% of providers selected a prepared rationale: 64% acute coronary syndrome/ST-elevation myocardial infarction/non–ST-elevation myocardial infarction; 30% demand ischemia; and 6% non-ACS myocardial necrosis. Of the remaining 35% of providers, 71% listed no rationale for their additional cTnI orders. Of patients with a BPA, 93% had non–ACS-related primary International Classification of Diseases, Revision 9 diagnosis, and 58% of the time, patients’ cTnI results never increased during their stay. In 53% of cases, BPAs were generated by a request for an additional cTnI series when ⬍2 results were available.
According to the Agency for Healthcare Research and Quality Healthcare Cost and Utilization Project, the mean cost of hospital stays in 2011 was $10 000, and although inpatient length of stay has shortened, the perday costs have increased ($2000 in 2009 vs $1400 in 1997 for all stays) (1 ). As hospital budgets tighten and reimbursements diminish, costs and value in health care are becoming major considerations for patients, providers, and hospitals. One strategy to improve the value of health care is the Choosing Wisely initiative (2 ). It suggests potential areas for reducing redundant and unnecessary laboratory testing within evidence-based practice, without compromising patient care. A major component of improving healthcare value is overall resource and utilization management by reducing unnecessary and ineffective services (3 ). If increased value is to be achieved, education on redundancy and utilization for both laboratory testing and treatments is necessary at the level of institutions, providers, and patients. Recently, the American College of Cardiology and American Heart Association highlighted the need for incorporating resource and value considerations during the generation of guidelines as well as during the evaluation of relevant evidencebased test/treatment recommendations for a specific patient (4 ). Cardiac troponin is a biomarker of myocardial injury but does not indicate any specific pathophysiology. The clinical context is critical to understanding and properly interpreting increased cardiac troponin concentrations. Best practices remain a challenge for cardiac troponin utilization with respect to timing and duration
Departments of 1 Laboratory Medicine and Pathology, 2 Clinical Informatics, 4 Medicine, Division of Cardiology, and 5 Emergency Medicine, Hennepin County Medical Center, Minneapolis, MN; Departments of 3 Occupational and Environmental Medicine, 6 Emergency Medicine, and 7 Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN.
* Address correspondence to this author at: Clinical Laboratories #812 701 Park Avenue, Hennepin County Medical Center, Minneapolis, MN 55415. Fax 612-904-4229; e-mail [email protected]. Received October 3, 2014; accepted December 1, 2014. Previously published online at DOI: 10.1373/clinchem.2014.234310
© 2014 American Association for Clinical Chemistry
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Copyright (C) 2014 by The American Association for Clinical Chemistry
of orders for the diagnosis or exclusion of acute myocardial infarction (AMI)8 (5–15 ). In 2013, our medical center adopted a single, timed, preset order for all cardiac troponin I (cTnI) testing. This order provides 4 cTnI results, at time of presentation (0 h) and at 3-h intervals subsequent to the initial draw (3, 6, and 9 h). This serial order set facilitates cTnI testing in several ways. First, it eliminates the need for multiple, separate orders by multiple providers, thus avoiding delays from separate electronic order entry by busy clinical providers. Second, the orders follow the patient between medical units within the hospital, lessening the likelihood of a missed blood draw during patient transfer between departments and providers. Third, in very low-risk patients for whom the emergency department physician is discharging the patient after ⬍4 troponin values, the remaining orders are automatically cancelled. The objectives of the current study were 2-fold. Our primary goal was to identify overutilization of cTnI testing on the basis of additional testing after a clinical diagnosis was determined. Our secondary goal was to identify which providers were ordering additional cTnI testing and in what clinical contexts. To attempt to provide utilization guidance in the cTnI ordering process and examine the rationale for ordering, a pop-up alert was implemented in the electronic health record (EHR), warning the ordering provider who attempted to place further cTnI orders after myocardial injury had already been diagnosed or excluded. METHODS
The changes to the process of cTnI ordering were all implemented in our institution’s EHR (Epic Systems Corp.) and went live (became available to clinicians) on August 6, 2013. Our EHR’s version at the time of implementation and analysis was Epic 2012. LIMITING cTnI ORDERING FREQUENCY AND NUMBER OF TESTS PER ORDER
We modified the existing order for cTnI so that (a) it could not be ordered more frequently than every 3 h and (b) it defaulted to 4 tests per order set. However, clinicians maintained the authority to change this number during the ordering process, either by manually changing the default or through a subsequent order. These changes were a divergence from the previous user-defined individual orders, which had varied in frequency or occurrences before initiation of this project, and thus comprised a default order series of 4 cTnI tests occurring
8
Nonstandard abbreviations: AMI, acute myocardial infarction; cTnI, cardiac troponin I; EHR, electronic health record; URL, upper reference limit; BPA, best practice alert; ACS, acute coronary syndrome; STEMI, ST-elevation MI; NSTEMI, non–ST-elevation MI; ICD-9, International Classification of Diseases, Revision 9.
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Clinical Chemistry 61:3 (2015)
every 3 h. These changes were seamless in the provider workflow to the extent that the process of cTnI ordering, including the appearance of the cTnI order, was in every other regard unchanged. Thus, providers would be able to discontinue remaining orders of a series if they were not clinically indicated [e.g., the first 2 cTnI values were ⬍99th percentile upper reference limit (URL) or a rising/ falling cTnI pattern was noted above the URL in the clinical setting to rule in an AMI]. IMPLEMENTATION OF cTnI COMPUTERIZED PHYSICIAN ORDER ENTRY ALERTS
We implemented a new EHR alert such that if a patient had ⱖ1 existing cTnI result in the past 30 days, any subsequent cTnI order would immediately trigger a best practice alert (BPA) pop-up window with the following text (Fig. 1A): “This patient has already had serial troponins ordered in the past 30 days. Troponins are a surrogate of myocardial injury and are often overutilized inappropriately. What is the suspected etiology of myocardial injury prompting a repeat of the troponin I series? If you choose ‘other’ below, please enter a comment using the ‘Acknowledge reason’ field.” In addition to the clinical decision support of the above text, the patient’s most recent cTnI values were displayed up to a maximum of the 5 most recent. The BPA required the user to select 1 of a list of clinical indications (Table 1, left column) for a repeat cTnI order before the BPA could be bypassed (i.e., a hard stop). Despite the requirement for an indication within the build of the BPA, workarounds for the BPA were discovered that could allow users to continue without specifying an indication, thus negating the intended BPA implementation as a hard stop. BPA indications were selected via single-click buttons immediately below the clinical decision support text. Free-text comments for the indication (intended particularly for the indication of “other”) were entered via a text field opened by a button adjacent to the selection of the indication, as displayed in Fig. 1A. DATA COLLECTION AND ANALYSIS
We acquired data through standard query language queries on our EHR’s extracted relational database (Epic Clarity). The primary cTnI orders dataset included all cTnI orders identified retrospectively that occurred during the study period. Critical primary order dataset variables are listed in Table 2. The primary cTnI alerting dataset included all instances of the BPA trigger during the study period, with cTnI values collected for the duration of the BPA-associated encounter. Critical alerting dataset variables are listed in Table 3. Data were analyzed in Microsoft Excel. Testing for cTnI was performed with EDTA plasma by use of the Architect i1000SR and i2000SR instru-
Cardiac Troponin Test Overutilization
Fig. 1. Findings derived from EHR BPA. (A), Alert text indicating possible overutilization, with ≤5 most recent cTnI results shown at time of BPA. (B), Number and percentage of users acknowledging the BPA and orders placed. (C), Primary providers observing BPAs, by clinical role. PGY, postgraduate year; PA, physician assistant.
ments (Abbott Laboratories), with a 99th percentile URL of 0.025 g/L (16 ). In accordance with standard hospital laboratory practices, duplicate orders within 2 h were combined at the time of collection to reduce the number of needle sticks for the patient (i.e., cTnI series ordered at
Table 2. Order data set variables. cTnI order data set variables Patient status (e.g., inpatient, outpatient, emergency)
Table 1. cTnI repeat-order BPA indications, as listed in BPA.
Order status (e.g., canceled) Ordering user Authorizing user (e.g. cosigned orders)
Possible alert indication
Selected, %
Patient location
ACS (STEMI or NSTEMI)
36
Ordering department
Demand ischemia
17
Order date/time
Non-ACS myocardial necrosis
3
Number of occurrences ordered
35
Number of occurrences released
None given
71
Number of occurrences completed
Chest pain
5
Primary hospital billed diagnosis
Retiming or ACS or trauma
2
Secondary hospital billed diagnosis
Other (free text entry)
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Table 3. BPA data set variables.
Table 5. Characteristics of BPA-associated patients (n = 702).
cTnI BPA data set variables Characteristic
Date/time user acted on BPA Number of instances of BPA for the same patient
Male, n
Selected indication
Female, n
Indication comments
Age, years, mean (range)
Date/time of order triggering the BPA
BPA frequency and timing, mean (range) cTnI tests per patient
User that triggered the BPA
1200 and 1230 were combined into a single series). This type of laboratory practice results in a significantly lower number of completed results then would be anticipated on the basis of the number of requests, which may underestimate the magnitude of laboratory testing. Results PROVIDER AND PATIENT DEMOGRAPHICS
The BPA was triggered 1477 times during the 2-month alert period (Fig. 1B). The BPAs occurred during 833 separate patient visits by 423 unique providers delivering care to 702 patients (summarized by role in Fig. 1C). A summary of the findings and demographics for BPAtriggering providers and associated patients are presented in Tables 4 and 5, respectively.
Value
404 298 56 (3–96) 3.6 (0–21)
Encounters per patient
1.2 (1–6)
BPAs per encounter
2.1 (0–12)
ICD-9 code ACS-related Patients, n
52
BPAs, n
106
cTnI results, n
316
Initially increased cTnI, %
59
cTnI became increased, %
23
cTnI never increased, %
17
Non–ACS-related Patients, n
650
BPAs, n
1368
cTnI results, n
2736
Initially increased cTnI, %
29
cTnI became increased, %
12
cTnI never increased, %
58
RATIONALE FOR ADDITIONAL ORDERING AND PROVIDER ACTION AFTER BPA
Table 4. EHR BPA-associated hospital unit and generating providers (n = 423). Provider or unit
BPAs, n (%)
Provider by training Resident
181 (42)
PGY1a
71 (40)
PGY2
48 (27)
PGY3
49 (27)
PGY4–6 Nurse
13 (7.2) 169 (40)
Attending
41 (9.7)
Other
32 (7.5)
Hospital unit
a
4
Cardiac-renal
482 (33)
Short-term observation
224 (15)
Emergency department
107 (7.2)
PGY, postgraduate year.
Clinical Chemistry 61:3 (2015)
When providers saw the BPA, they overwhelmingly (n ⫽ 1440, 97%) acknowledged and overrode the BPA (Fig. 1A). For overridden BPAs, providers selected from the prompted list 929 times (65%), selecting acute coronary syndrome (ACS) concern [ST-elevation MI (STEMI) and non–ST-elevation MI (NSTEMI)], n ⫽ 519 (35%); demand ischemia, n ⫽ 249 (17%); and non-ACS myocardial necrosis, n ⫽ 50 (3%). Of the providers electing to describe the clinical indication by free text entry, 71% gave no indication. Of the 29% of providers that described the clinical indication, the 5 most common answers were related to chest pain (n ⫽ 23), retiming (n ⫽ 11), ACS (n ⫽ 10), trauma (n ⫽ 7), or emergency department visit (n ⫽ 6). TROPONIN RESULTS AND ALERTS: TIMING AND INCREASES
The generated BPAs were associated with 3045 completed cTnI results. For each of the 833 patient visits, a mean of 3.6 cTnI results were completed (95% CI 3.6 – 3.8, range 0 –21). A mean of 1.8 cTnI results were available before a BPA and 2.5 cTnI results after a BPA. Be-
Cardiac Troponin Test Overutilization
Fig. 2. Box-and-whisker plot of number of cTnI results per patient, in ACS and NON-ACS (A) patients and number of cTnI results per patient, by BPA alerting primary provider’s clinical role (B). PGY, postgraduate year; RN, nurse; MD, doctor; PA, physician assistant.
fore a single cTnI result was available, 347 (23%) BPAs were triggered, and almost 800 BPAs were generated when ⱕ1 results were available. In other words, providers were ordering new sets when the first order set had only begun to be carried out. The first cTnI value was increased (above the 99th percentage reference) in 238 patient visits (30%), increasing to 359 (43%) over the duration of cTnI testing. Of those patients with initially increased cTnI values, 205 (86%) remained increased for the duration of measured cTnI results and, of those 205, 0 –17 additional cTnI results were reported after the first BPA, with 77% having 1– 4 additional results. ACS ENCOUNTERS
According to associated International Classification of Diseases, Revision 9 (ICD-9) codes for the BPA-related encounters, 52 patients had an ACS diagnosis for STEMI (n ⫽ 19), NSTEMI (n ⫽ 9), or unstable angina (n ⫽ 24). These patients had a mean of 6 (95% CI 5.3–7.0, range 3–16) cTnI results, as shown in Fig. 2A. Of these patients, 59% presented with initially increased cTnI values, of which 86% remained increased throughout. Of those with an initially increased cTnI, 66% had ⱖ5 cTnI results during admission. Of those patients presenting without an initial increase, 23% increased over serial measurements and 61% had ⱖ5 cTnI results during their admission. NON-ACS ENCOUNTERS
The 650 patients who did not have a final ACS-related diagnosis were associated with 92% of BPAs. They had a mean of 4 (95% CI 3.3– 4.6, range 0 –21) cTnI results, as shown in Fig. 2B. Of these patients, 29% presented with an initially increased cTnI value, of which 80% remained increased. Of those without an initial increase, 12% became increased and 58% did not have concentrations above the URL during their hospitalization. Of the non-
ACS encounters within this cohort, 21% had ⱖ5 cTnI results during admission. Discussion Our findings are interesting in several ways. First, we observed that, at our institution, cTnI testing is overutilized in the clinical care of patients presenting to rule in or rule out AMI. Second, providers, even when notified that their cTnI testing is likely excessive, largely overrode visual BPAs to modify their ordering practices. Third, the largest absolute number of inappropriate cTnI orders was by residents, reflective of the overall ordering pattern within our institution, despite supervised training with faculty, in moderate- to high-risk patients (telemetry unit) and patients with a non-MI diagnosis. Our current findings validated our hypothesis that providers overutilize cTnI testing. The 3045 BPA-related cTnI results were roughly 50% of the total hospital’s 6025 completed cTnI results during the alert period. Our routine laboratory practice is to combine or cancel multiple/duplicate orders, and when possible to minimize patient blood draws. This standard practice prevents a substantial number of inefficient orders from being completed, which for the purpose of the current study underestimates the extent of cardiac troponin overutilization. In theory, if all of the additional order sets requested were completed and no duplicate orders were combined, approximately 7000 additional cTnI results would have been reported. According to the Third Universal Definition of Myocardial Infarction (5 ), a clinical decision to rule in or rule out AMI would be possible by the fourth cTnI result and, without a change in clinical context, additional measurements would be deemed unnecesClinical Chemistry 61:3 (2015) 5
sary for diagnostic purposes. Without adjudicating each of these cases, the level of overutilization is not precisely known. If one considers that each evaluation for a given encounter would require 4 cTnI results to rule in or rule out AMI, the most straightforward set of patients would be those with a diagnosis of STEMI. In that subset, there was a mean of 6 (95% CI 5.3–7.0) cTnI results. This would indicate that within this alerting cohort, a conservative estimate of 32% of the cTnI results were unnecessary and therefore cTnI was overutilized. This volume of wasteful testing is a considerable financial burden, estimated to be hundreds of thousands of dollars a year, affecting both patient charges and hospital direct costs, without adding value to patient care (14 –16 ). On the basis of the evidencebased Third Universal Definition of Myocardial Infarction guidelines, and in light of the fact that 53% of BPAs were generated before there were 2 cTnI results, a substantial number of providers were requesting additional cTnI testing without having sufficient data to provide a clear picture of rising/falling pattern within the cTnI results. As cTnI ordering in the current study was not statistically different from that of the 2 months after the alert period (data not shown), the BPA did not decrease the overutilization of cTnI within the institution. Thus, our primary objective to reduce overutilization of cTnI was not successful. Given the overwhelming response of providers to acknowledge and override the BPA within the EHR, this was not an effective tool to reduce test ordering. One interpretation of this would be that ordering providers found this BPA similarly irritating to the pop-up windows found while casually browsing the internet, which most individuals attempt to close as quickly as possible. Our secondary objective was to determine who was ordering additional cTnI testing and for which patients. As shown in Fig. 1C and Tables 4 and 5, ordering providers with BPAs were predominantly within their first 3 years of residency, and patients were ultimately not found to have an ACS-related diagnosis. Because ours is a teaching hospital, the majority of any laboratory test ordering, including cTnI, is placed by residents. BPA generation was predominantly for patients from the cardiac-renal unit, accounting for 33% of all BPAs and more than twice the rate compared with the short-term observation unit, where most suspected ACS patients from the emergency department go for continued observation during the remainder of the time required to rule in or rule out ACS. For the patients in the cardiac-renal unit, the top 2 categories of ICD-9 diagnoses were related to heart failure and renal disease. Our findings highlight the important role that the clinical scenario plays in 6
Clinical Chemistry 61:3 (2015)
proper utilization at the time of cTnI ordering. With the advent of high-sensitivity cardiac troponin assays, this issue will become even more critical as we begin to more accurately measure lower concentrations of cardiac troponin (5, 8, 17–20 ). When patients had ACS, providers did no better at utilizing cTnI, since monitoring of cTnI continued beyond those tests needed for the ACS diagnosis. Within our alerting cohort, we found there were 102 BPAs for the 52 patients with an ACS diagnosis, with ⬎60% having ⱖ5 cTnI results. These patients had 315 results collectively, with a mean of 6 results/patient, which is similar to a recent study in our hospital examining 100 consecutive cardiac-renal unit patients (21 ). Within that study, in which all included patients were adjudicated by a cardiologist, 48% of the cTnI results occurred after the ACS diagnosis had already been made. Although that study preceded our BPA period, and we did not have a cardiologist adjudicate patient results, our alert data do suggest that a similar level of overutilization continued during the alert period within our hospital. The following limitations for our study are noted. First, the implementation of the BPA was incomplete, since it allowed users to dismiss it without providing a rationale for their requests. Second, because the BPA was implemented at the same time as a uniform cTnI order, no direct comparison could be made to utilization before its implementation. Potential corrective actions that require further study to decrease overtesting could include (a) implementing a true hard stop (one that cannot be overridden) in our EHR/Epic order system to prevent overuse at order entry, (b) continued hospital-wide education using conferences and emails with evidence guideline literature on the proper use of cTnI testing, and (c) meetings with the Office of the Medical Director’s Quality Assurance staff to engage division chiefs to support reducing orders during non–ACS-related evaluations. In conclusion, our data show that (a) cTnI testing for diagnosis and exclusion of AMI is overutilized, (b) visual alerts did not result in a decrease in excessive cTnI orders by providers, even after a diagnosis was determined, (c) the largest number of ignored alerts was in non-ACS patients, and (d) even providers treating patients already diagnosed with AMI practiced excessive cTnI ordering. More appropriate cTnI utilization could provide substantial financial savings without compromising patient care. Effective means of encouraging appropriate utilization need to be explored.
Author Contributions: All authors confirmed they have contributed to the intellectual content of this paper and have met the following 3 requirements: (a) significant contributions to the conception and design,
Cardiac Troponin Test Overutilization
acquisition of data, or analysis and interpretation of data; (b) drafting or revising the article for intellectual content; and (c) final approval of the published article. Authors’ Disclosures or Potential Conflicts of Interest: Upon manuscript submission, all authors completed the author disclosure form. Disclosures and/or potential conflicts of interest: Employment or Leadership: F.S. Apple, Clinical Chemistry, AACC. Consultant or Advisory Role: Y. Sandoval, Roche Diagnostics; F.S. Apple, Instrumentation Laboratory, Phillips.
Stock Ownership: None declared. Honoraria: None declared. Research Funding: F.S. Apple, nonsalaried research funding from numerous manufacturers of cardiac troponin assays through the Minneapolis Medical Research Foundation of Hennepin County Medical Center. Expert Testimony: None declared. Patents: None declared. Role of Sponsor: No sponsor was declared. Acknowledgments:
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