Implementation of Acute Myocardial Infarction Guidelines in Community Hospitals

Transcription

1 522 Larson et al. d IMPLEMENTATION OF AMI GUIDELINES Implementation of Acute Myocardial Infarction Guidelines in Community Hospitals Abstract Objectives: To obtain information regarding the current use of guidelines and protocols and quality assessment practices for the management of ST-segment elevation myocardial infarction in Minnesota hospitals without cardiac catheterization laboratories. Methods: Structured surveys were mailed in 2003 to emergency department medical directors or nurse managers in 111 hospitals in Minnesota that did not have cardiac catheterization laboratories. Of the 111 hospitals surveyed, 104 (94%) responded. Results: Sixty-three percent of responding hospitals have guidelines or protocols; 57% use standing orders for ST-segment elevation myocardial infarction. Thirty-three percent have neither. Of those with guidelines, protocols, or standing orders, 8% address triage and transfer criteria, 86% thrombolytics, 91% aspirin, and 71% beta-blockers. Fifty percent have quality assessment processes in place for ST-segment elevation myocardial infarction. Conclusions: Recommendations from the National Heart Attack Alert Program issued DavidM.Larson,MD,ScottW.Sharkey,MD, Barbara T. Unger, RN, Timothy D. Henry, MD more than ten years ago and, more recently, the updated American College of Cardiology/American Heart Association Guidelines for the Management of Patients With ST- Elevation Myocardial Infarction suggest development of emergency department and hospital-specific guidelines and protocols for ST-segment elevation myocardial infarction. Currently, only two thirds of community hospitals in Minnesota have these in place; when present, these guidelines are often incomplete and rarely address transfer criteria to hospitals with percutaneous coronary intervention capability. Quality assessment occurred in 50% of hospitals surveyed. Programs to help community hospitals develop and implement guidelines and quality improvement should be encouraged and supported. Key words: guidelines; ST-segment elevation myocardial infarction; rural; quality. ACADEMIC EMERGENCY MEDICINE 2005; 12: Coronary artery disease remains the number one cause of death in the United States and the world today. Significant progress has been made in the diagnosis and management of acute ST-segment elevation myocardial infarction (STEMI) over the past 20 years. 1,2 Despite these advances, implementation of data into clinical practice has been variable. Significant geographic variations exist in the use of aspirin and beta-blockers in patients with acute myocardial infarction (AMI). 3 Failure to adhere to clinical guidelines for the treatment of AMI occurs to a greater extent in rural and semirural hospitals compared with urban hospitals. 4 In STEMI, rapid and sustained reperfusion of the infarct-related artery, either by primary percutaneous coronary intervention (PCI) or thrombolytic therapy, results in decreased mortality From the Department of Emergency Medicine, Ridgeview Medical Center (DML), Waconia, MN; and Minneapolis Cardiology Associates, Minneapolis Heart Institute Foundation (DML, SWS, BTU, TDH), Minneapolis, MN. Received December 20, 2004; revision received January 4, 2005; accepted January 7, Supported in part by the Bush Foundation (St. Paul, MN). Address for correspondence and reprints: David M. Larson, MD, Minneapolis Heart Institute Foundation, 920 East 28th Street, Suite 40, Minneapolis, MN Fax: ; dlarsonmd@ visi.com. doi: /j.aem and morbidity. 2 However, up to 30% of eligible patients do not receive reperfusion therapy. 5 To improve quality of care and reduce delays to treatment of STEMI, the National Heart Attack Alert Program recommended in 1993 that emergency departments (EDs) develop protocols for STEMI and monitor quality measures, including time-to-treatment intervals. 6 The recently updated American College of Cardiology/American Heart Association (ACC/AHA) guidelines on STEMI recommend hospital-specific protocols to rapidly assess and treat patients with STEMI. 2 The purpose of this study was to obtain information regarding the current use of STEMI protocols, adherence to guidelines, quality assessment practices, and decision making regarding treatment and transfer criteria in hospitals without cardiac catheterization laboratories in Minnesota. METHODS Study Design. This was a survey study to determine presence and adherence to hospital-specific protocols and guidelines for treatment of patients with acute STEMI. Because of its voluntary nature, this study was considered exempt from informed consent. Survey Content and Administration. In 2003, surveys were mailed to ED medical directors and nurse

2 ACAD EMERG MED d June 2005, Vol. 12, No. 6 d managers in 111 Minnesota hospitals without cardiac catheterization laboratories to assess the prevalence of preexistent standardized treatment of patients with STEMI in a cross-sectional fashion. Specifically, the survey asked questions regarding protocol/guidelines, standing orders, quality assurance, decision making, and indications for transfer of patients with STEMI as well as hospital size and distance to the nearest cardiovascular catheterization laboratory. A second letter was sent within six months, followed by telephone calls to hospitals not responding to the initial survey. Data Analysis. To quantify the response to the survey, continuous variables were expressed as mean 6 SD (range), and discrete variables and categorical data were analyzed in a numerical or percentage fashion. Distribution of hospital size and distance from referring to tertiary hospitals with regard to transfer of patients (overall or directly from the ED) achieved was stratified into percent quintiles by the transfer of patients (100%, 90% 99%, 75% 89%, 50% 74%, and,50%). Analysis of variance was used to determine statistically significant relationships between categories of data in the quintiles. Univariate regression established significance of relationships between the percent transfer achieved and either hospital size or the distance, and multivariate regression analysis was performed to determine the significance of the combined relationship. Correlations were expressed through Spearman s correlation coefficients. Decision-making and other categorical data were compared with Yates corrected chi-square. Analysis of the data was performed with GB-STAT statistical software version 9.0 (Dynamic Microsystems, Silver Springs, MD). In all analyses, p, 0.05 was considered significant. RESULTS Of the 111 Minnesota hospitals without catheterization laboratories, 104 (94%) responded to the survey. The surveys were completed by ED medical directors (35%) and ED nurse managers (35%) or were not specified (30%). Hospital size ranged from ten to 173 beds (mean 6 SD, ) Seventy-three percent of hospitals had,50 beds, 20% had beds, and 7% had.100 beds. Distance to the nearest hospital with cardiac catheterization facilities ranged from 12 to 300 miles (mean 6 SD, ). Eleven percent were,30 miles, 36% were miles, 24% were miles, and 29% were.90 miles (see map in Figure 1). STEMI Protocols and Guidelines. Sixty-three percent of responders indicated that they had hospitalspecific written protocols or guidelines in the ED regarding the management of STEMI. Standing orders for treatment of STEMI were used in 57% of hospitals. Figure 1. Map of Minnesota. Large circles indicate location of cardiac catheterization centers, and small circles indicate location of hospitals without cardiac catheterization laboratories. Abbot Northwestern is the referral hospital for the Minnesota Heart Institute. Thirty-three percent had neither written protocols/ guidelines nor standing orders. In hospitals that had specific guidelines, the issues addressed varied considerably and frequently were incomplete. For example, only the indications for thrombolytics and the indications and recommended dosing for aspirin and unfractionated heparin were addressed in at least 80% of the hospitals (Table 1). Hospital guidelines addressed triage and transfer criteria to a tertiary cardiovascular center in 8% of hospitals. TABLE 1. Frequency of Specific Treatment Issues for STEMI, Addressed in Protocols, Standing Orders, or Guidelines of a Referring Community Hospital Do the Protocols, Standing Orders, or Guidelines Address the Following? No. (%) Answering Yes (n = 70) Indications for a thrombolytic drug 60 (86) Name of a specific thrombolytic and dose 55 (78) Indications and dose of beta-blocker 50 (71) Indications and dose for aspirin 64 (91) Indications and dose of unfractionated heparin 56 (80) Indications and dose of low-molecular-weight heparin 24 (34) Indications and dose of intravenous nitroglycerin 41 (58) Triage and transfer criteria 6 (8)

3 524 Larson et al. d IMPLEMENTATION OF AMI GUIDELINES Decision-making and Transfer Issues. To assess the decision-making responsibilities regarding reperfusion therapy and transfer decisions, the survey asked to estimate how these decisions were most often made (Figure 2). Fifty-five percent (57/104) of responders stated that the decision to administer a thrombolytic is made by the emergency physician independently. This decision is made only after telephone consultation with a cardiologist in 22% (23/104) or with the attending physician in 8% (8/104). Fifteen percent (16/104) said that the decision is made by the emergency physician based on a written protocol. The decision to transfer the patient directly from the ED to a tertiary hospital is made by the emergency physician independently in 35% (36/104) of hospitals surveyed. This decision is made only after telephone consultation with a cardiologist in 48% (49/104) or with the attending physician in 16% (18/104). A written protocol is used to make the transfer decision in only 1% of hospitals. When transferring a patient with STEMI to a tertiary facility, the preferred method of transport is by helicopter in 59%. Seventy percent of hospitals are within 90 miles and 57% are within 60 miles of a PCI center. When asked to estimate what percent of STEMI patients (younger than 75 years of age) are ultimately transferred to another hospital for specialized cardiovascular care, 32% of hospitals responding to the survey indicated that 100% of STEMI patients are transferred. In contrast, 7% of hospitals transfer,50% of STEMI patients. Hospitals with fewer beds were significantly more likely to transfer STEMI patients; however, the distance from a specialized cardiology center does not appear to influence the decision to transfer (Table 2). While 93% of hospitals indicated that.50% of patients were ultimately transferred, the number transferred directly from the ED was lower and more Figure 2. Percent distribution of hospitals reflecting decisionmaking responsibilities for thrombolytic therapy compared with decision for direct transfer from the ED. likely to occur in hospitals within a shorter distance to the tertiary facility (Table 3). Quality Assurance. Fifty percent of hospitals surveyed reported that they have a formal quality assessment process that monitors all STEMIs. The average size of hospitals with a formal quality assessment process was 50 beds versus 34 beds in those hospitals without. Of the hospitals responding to the survey, 53% monitor door-to-drug intervals, 36% report utilization rates of thrombolytics, 46% report utilization of aspirin, and 35% report utilization of beta-blockers (Table 4). Only 7% of those hospitals responding to the survey participate in the National Registry of Myocardial Infarction. Responding hospitals were matched with the list of accredited hospitals provided by the Joint Commission on Accreditation of Healthcare Organizations (JCAHO). Sixty-two percent of hospitals were not accredited by JCAHO. DISCUSSION The recently updated ACC/AHA guidelines, as well as the National Heart Attack Alert Program publication in 1993, recommend hospital-specific guidelines and protocols for STEMI. Our survey found that currently two thirds of community hospitals in Minnesota have these in place. However, these guidelines are often incomplete and rarely address transfer criteria to hospitals with PCI capability. Quality performance measurement occurred in 50% of hospitals surveyed. There continues to be a discordance between established clinical guidelines for AMI and real-life clinical practice in both Europe 7 and the United States. 8,9 Therefore, it is not surprising that these recommendations have not yet been implemented in many of the hospitals that we surveyed. The purpose of guidelines, protocols, and structured order forms is to reduce variability in care, to implement evidencebased clinical research, and to decrease time to treatment. Ultimately, this will lead to improved patient outcomes and quality of care. 10 The ACC s Guidelines Applied in Practice Program has demonstrated a significant decrease in 30-day and one-year mortality using guidelines-based standardized care. 11 Published guidelines attempt to standardize care but may be out of date because of rapid advances in medical knowledge and are not specific for an individual facility. Adherence to AMI guidelines has been shown to improve when local medical opinion leaders are involved in development. 12 Hospital-specific guidelines and tools such as structured order forms, clinical pathways, or pocket cards are best established with input from local experts. Small rural hospitals often do not have on-site cardiologists and therefore depend on consultants from regional centers. Programs to help community hospitals develop and

4 ACAD EMERG MED d June 2005, Vol. 12, No. 6 d TABLE 2. Estimate of the Percent of STEMI Patients Ultimately Transferred to a Tertiary Hospital STEMI Patients Transferred No. of Hospitals (%) Hospital Size (Beds), Mean 6 SD (Range) Distance (Miles), Mean 6 SD (Range) 100% 32 (0.32) (10 66) (22 300) 90% 99% 27 (0.27) (15 150) (12 160) 75% 89% 22 (0.22) (15 140) (30 150) 50% 74% 11 (0.11) (14 50) (20 125),50% 7 (0.07) (66 173) (12 90) Univariate p-value, NS Multivariate p-value, implement guidelines should be encouraged. The Guidelines Applied in Practice initiative of the ACC is an example in which customized guidelinesoriented tools are used to improve quality of care for STEMI. 13 Ongoing quality assessment/improvement of STEMI management is recommended to improve outcomes. Process of care quality measures for AMI include various indicators such as time to reperfusion and utilization of aspirin and beta-blockers. 10 Smaller hospitals may not have the resources (staff and/or infrastructure) for a formal quality assessment/quality initiative process. Governmental and other outside agencies also measure quality performance pertaining to AMI. The Centers for Medicare and Medicaid Services report on several AMI quality indicators, but this includes only Medicare beneficiaries (primarily fee for service). 14 JCAHO has recommended monitoring door-to-drug and door-to-balloon intervals as one of the core quality measures ( pms/core). However, as noted in our survey results, 62% of rural hospitals are not accredited by JCAHO. The National Registry of Myocardial Infarction, a prospective observational registry, 15 is another source of national data regarding STEMI; however, most of our hospitals do not participate in this registry (data not shown). It is also unusual for rural and community hospitals to participate in randomized clinical trials. Therefore, not only is there a paucity of quality data regarding outcome in STEMI from rural hospitals, there is also limited representation of rural STEMI patients in large randomized trials. Cardiovascular centers that have referral relationships with these hospitals could assist with data collection, quality improvement, and research. Time to treatment (door to drug or door to balloon) is a key quality indicator because delays in reperfusion therapy are linked to increased mortality. 16,17 Previous studies have shown that contacting the primary physician or cardiologist before initiating thrombolytic treatment results in a significant delay. 18 Despite these data, our survey indicates that for.30% of patients, a primary care physician or cardiologist is consulted before a decision regarding reperfusion therapy is made. Delays to reperfusion therapy occur while these treatment decisions are being considered. Hospital-specific guidelines allow these decisions to be made by the emergency physician to decrease time to treatment. Approximately two thirds of patients with STEMI present to hospitals without cardiac catheterization capability. 19 Recent data suggest that primary PCI is preferred over thrombolysis even when patients are transferred to another facility with door-to-balloon times of up to two hours Seventy percent of hospitals we surveyed are located within 90 miles (30- minute transport time by helicopter) of a PCI center. An organized system with prearranged triage and transfer guidelines (especially using helicopter transports) would allow primary PCI within the 120- minute door-to-balloon window for most of these patients. Recent registry data from the National Registry of Myocardial Infarction have shown that only 15% of patients transferred for primary PCI actually have door-to-balloon times of,120 minutes. 24 For those hospitals that are at greater distances or are TABLE 3. Estimate of the Percent of STEMI Patients Transferred Directly from the Emergency Department to the Tertiary Hospital Patients Who Are Transferred Directly from the ED No. of Hospitals (%) Hospital size (Beds), Median (Range) Distance (Miles), Median (Range) 100% 22 (0.23) (25 150) (10 66) 90% 99% 33 (0.35) (14 173) (12 200) 75% 89% 10 (0.10) (15 125) (12 150) 50% 74% 6 (0.06) (15 100) (60 160),50% 24 (0.25) (15 140) (20 300) Univariate p-value NS Multivariate p-value 0.008

5 526 Larson et al. d IMPLEMENTATION OF AMI GUIDELINES TABLE 4. Quality Assessment Parameter No. (%) Hospitals with a formal quality assessment process that reviews all STEMIs 52 (50) Monitoring of door-to-drug intervals 55 (53) Utilization of thrombolytics 37 (36) Utilization of aspirin 47 (46) Utilization of beta-blockers 36 (35) Utilization of intravenous nitroglycerin 20 (19) unable to transfer within the two-hour window, thrombolytic therapy remains the reperfusion method of choice. However, because only 60% of patients will achieve TIMI 3 flow in 90 minutes, 25 there may be benefit for early transfer of all STEMI patients, even if treated locally with thrombolytics, for rescue or facilitated angioplasty. In addition, there are data to suggest that outcomes with STEMI are superior when managed by a cardiovascular specialist in highvolume cardiovascular centers. 26,27 Results from our survey demonstrate significant variability regarding the timing and the decision to transfer STEMI patients to PCI centers. Larger hospitals were less likely to transfer patients than smaller hospitals, even though the distances to the cardiovascular center were less. To improve the care of STEMI patients and implement recent clinical data, we recently initiated a collaborative effort between the Minneapolis Heart Institute and 25 rural and community hospitals. 28,29 The goal of the Level 1 Heart Attack program is to develop a standardized, integrated, and well-coordinated system of care for STEMI patients who present to hospitals without PCI capability. In addition to standardized care based on up-to-date hospital-specific guidelines, this program allows rapid transfer for primary or facilitated PCI. Rapid-cycle quality assessment data are collected and reported back to community hospitals, allowing for continuous improvement. Long-term patient outcomes are also provided to the referring hospital. LIMITATIONS Our study is limited by the fact that this is a survey. Even though an ED may have a guideline or protocol, we were unable to assess how often these were actually used or the role the guidelines played in clinical decision making. Therefore, we may have overestimated the role of guidelines in the management of STEMI. Because this was a survey, the data regarding transfer and decision making are only estimates and we are not able to accurately quantify the number of patients actually transferred or confirm how the decision to transfer was made. There may have been factors other than existing guidelines that influenced treatment and transfer decision making. We are not able to make any inferences regarding outcome measures or the quality of care delivered to STEMI patients by the hospitals surveyed because this survey only inquired about quality performance. CONCLUSIONS Regardless of the reperfusion strategy, the literature suggests that all STEMI patients benefit from early transfer to a cardiovascular center with 24-hoursa-day/7-days-a-week cardiac catheterization capability. 30 To optimize outcomes, reduce variability, and avoid delays to reperfusion, hospital-specific treatment and transfer protocols should be collaboratively developed by referring hospitals and cardiovascular centers. The recently updated ACC/AHA Guidelines for the Management of Patients With STEMI recommend (Class I) that hospitals should establish multidisciplinary teams (including primary care physicians, emergency medicine physicians, cardiologists, nurses, and laboratorians) to develop guideline-based, institutional-specific written protocols for triaging and managing patients who are seen in the out-of-hospital setting or present to the ED with symptoms suggestive of STEMI and the choice of initial STEMI treatment should be made by the emergency physician on duty based on a predetermined, institution-specific, written protocol. 4 Quality assessment and improvement is essential for all hospitals caring for STEMI patients. Our results suggest that some community hospitals have not yet developed guidelines for patients with STEMI and, of those with guidelines, they are often incomplete. 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