Safety of Assessment of Patients With Potential Ischemic Chest Pain in an Emergency Department Waiting Room: A Prospective Comparative Cohort Study
Article Outline
- Abstract
- Introduction
- Materials and Methods
- Results
- Limitations
- Discussion
- Acknowledgment
- References
- Copyright
Study objective
Emergency department (ED) crowding has been associated with a variety of adverse outcomes. Current guidelines suggest that patients with potentially ischemic chest pain should undergo rapid assessment and treatment in a monitored setting to optimize the diagnosis of acute coronary syndrome. These patients may be at high risk of incorrect diagnosis and adverse events when their evaluation is delayed because of crowding. To mitigate crowding-related delays, we developed processes that enabled emergency physicians to evaluate potentially sick patients in the waiting room when all nurse-staffed stretchers are occupied. The objective of this study was to investigate the safety of waiting room chest pain evaluation.
Methods
This prospective comparative cohort study was conducted in a busy urban, tertiary care ED. Explicit triage and waiting room evaluation processes were introduced. One thousand one hundred seven patients with chest pain of potential cardiac origin were triaged either to a monitored bed or a waiting room chair, depending on bed availability and triage judgment. After diagnostic evaluation, patients were followed for 30 days to identify the proportion of missed cases of acute coronary syndrome (primary outcome) and other prespecified adverse events. Analysis was based on intention to treat.
Results
Eight hundred four patients were triaged to monitored bed and 303 to waiting room evaluation. Initial vital signs were similar, but the waiting room group was younger and had lower rates of some cardiovascular risk factors. The rate of acute coronary syndrome, defined as acute myocardial infarction or objective unstable angina, was 11.7% in the monitored bed group and 7.6% in waiting room patients. There were no missed acute coronary syndrome cases in either the monitored bed group (0%; 95% confidence interval [CI] 0% to 0.4%) or the waiting room group (0%; 95% CI 0% to 1.0%). There were 32 adverse events in the monitored bed group (4.0%; 95% CI 2.6% to 5.3%) and 2 in the waiting room group (0.7%; 95% CI 0% to 1.6%).
Conclusion
Our organized approach to triage and waiting room evaluation for stable chest pain patients was safe and efficient. Although waiting room evaluation is not ideal, it may be a feasible contingency strategy for periods when ED crowding compromises access to monitored, nurse-staffed ED beds.
Introduction
Background
Emergency department (ED) crowding is a global phenomenon, with a growing literature describing its causes, implications, and potential solutions.1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 When crowding compromises access to emergency care, sick patients often face prolonged delays in ED waiting rooms or hallways. Delayed physician assessment, diagnosis, and therapy are associated with a variety of negative outcomes, ranging from prolonged pain and suboptimal management of infectious diseases to delayed thrombolytic administration.12, 13, 14, 15, 16, 17, 18, 19, 20, 21 Patients who present to the ED with chest pain and possible acute coronary syndromes are an important group who may be at substantial risk when evaluation is delayed.
What is already known on this topic
Crowding can lead to delays in the evaluation and management of patients.
What question this study addressed
Can selected emergency department (ED) patients complaining of chest pain safely receive some or all of their care in the waiting room?
What this study adds to our knowledge
There were no missed cases of acute coronary syndrome and no important complications in the 303 patients triaged to the waiting room.
How this is relevant to clinical practice
This study suggests that with careful triage and prompt physician assessment, waiting room management might be an adequate, albeit not optimal, means of managing low-risk chest pain patients when there are no monitored beds available in the ED.
Research we'd like to see
Replication of this study with a larger number of subjects at multiple sites will be needed to establish exactly how safe this strategy is.
Every year in the United States, approximately 6 million patients with chest pain arrive at an ED.22 The 2007 American College of Cardiology/American Heart Association guidelines recommend that ED patients with possible cardiac ischemia undergo immediate assessment by an emergency triage nurse and physician and receive an ECG within 10 minutes. These recommendations also suggest that patients with an initial nondiagnostic ECG result undergo prolonged observation (up to 12 hours after onset of symptoms), continuous cardiopulmonary monitoring, and testing of serial ECG cardiac biomarkers.23 The European Society of Cardiology has advised a similar approach.24 Despite this, 2% to 5% of patients with acute coronary syndrome are inappropriately discharged from the ED index visit with an incorrect minimizing diagnosis.25, 26 Such patients are at higher risk of adverse outcomes than patients who are initially admitted.25 Cases of missed acute coronary syndrome are estimated to account for 25% of all ED litigation costs.27, 28
Because of frequent crowding, large numbers of emergency and urgent patients are often triaged to the waiting room. In this environment, they do not traditionally benefit from timely nurse and physician assessment, rapid electrocardiography, or ongoing cardiopulmonary monitoring. To mitigate the risk associated with delayed diagnosis, we developed processes that enable emergency physicians to evaluate potentially sick patients in the waiting room when all nurse-staffed stretchers are occupied. This process provides an innovative care option during ED gridlock and a surge capacity strategy during periods of high inflow; however, the safety and medicolegal ramifications of assessing patients with potential cardiac ischemia in a minimal-resource area such as the waiting room have not been studied. Our objective was to describe the outcomes of a cohort of ED patients with chest pain who were assessed in the waiting room and to compare this with a concurrent cohort of patients who were placed in a formal ED bed with cardiopulmonary monitoring and an attending nurse. We hypothesized that monitored bed and waiting room patients would have a similar rate of missed acute coronary syndrome diagnoses and ED adverse events.
Materials and Methods
Setting
Vancouver, Canada, has 6 EDs with a combined annual census of 250,000 patient visits. The study site, St. Paul's Hospital, is a 600-bed inner-city tertiary care center with 60,000 annual ED visits and 24-hour cardiac catheterization capability. The ED has an acute medical-surgical area with 18 monitored beds and 1 resuscitation bay, a “fast-track” area for lower-acuity patients, a clinical decision unit, and a mental health–substance misuse area. There is a dedicated ED phlebotomist available 24 hours a day, and dedicated ECG and radiograph technicians, from 7 am to 7 pm. The latter employees are available from 7 pm to 7 am but have additional responsibility for urgent ECGs and imaging throughout the entire hospital.
Canadian tertiary care EDs use a standardized, validated triage tool known as the Canadian Triage and Acuity Scale (CTAS), a 5-point scale with high interrater reliability, developed in 1998 by the Canadian Association of Emergency Physicians.29, 30, 31 At our institution, all triage is performed by nurses with specific CTAS training. CTAS level 1 patients require immediate resuscitation (eg, cardiac arrest, major trauma), whereas level 5 patients are considered nonurgent. Individuals with chest pain of potentially cardiac origin are assigned to level 2, with a physician assessment target time of 15 minutes or less. Patients with potential cardiac chest pain are triaged directly to a monitored bed if one is available. If not, they are triaged directly to the waiting room and an emergency physician is notified. In some cases, the triage nurse and the emergency physician will, after discussion, move a stable boarded patient in a monitored bed into an unmonitored hallway bed to create a monitored bed for a new cardiac patient. Alternatively, after similar discussion, a new stable chest pain patient may be evaluated in the waiting room to preserve nurse-staffed stretchers for sicker patients. Because our physicians respond to patients in the waiting room, they often play a role in deciding where patients are initially triaged.
To facilitate timely physician assessment of potentially ill patients during surge periods and when no ED care spaces are available, we placed 3 curtained stretchers in our main patient waiting room, along with a computerized physician order entry terminal. After examining patients in the waiting room, emergency physicians can directly order any necessary laboratory tests, imaging, treatment, or consultation. Technicians respond to the waiting room to perform ECGs and laboratory tests or to transport patients for necessary imaging; therefore, complete diagnostic evaluations can occur even when no traditional ED care spaces are available. If emergency physicians identify high-risk clinical or electrocardiographic features during a waiting room examination, they may request that the patient be prioritized for the next available monitored ED stretcher. Otherwise, diagnostic investigations are completed in the waiting room. No nursing staff is assigned to the waiting room, but a triage nurse has direct visualization of all patients during their waiting room stay.
Data for the waiting room safety study were derived from a prospective, observational cohort of ED chest pain patients enrolled between February 1, 2006, and September 29, 2006, to validate a clinical decision rule for early discharge of patients with chest pain. In this study, patients presenting to the ED with a chief complaint of potential ischemic chest pain were eligible. Patients were excluded if they were younger than 25 years, had a clear traumatic or radiologically evident alternate cause of chest pain, were previously enrolled in the study within 30 days, had a terminal noncardiac illness, had debilitating communication problems, had no telephone contact, or were without a fixed address. This study had ethical approval from the Providence Health Care–University of British Columbia Research Ethics Board.
For the purpose of the waiting room safety substudy, we stratified patients into 2 groups with intention-to-treat analysis: those who were triaged to the waiting room and those triaged to a monitored bed. From an ethical perspective, the waiting room safety substudy was considered a quality assessment of an established care process and a hypothesis-generating study from an existing research database that posed no additional risk to patients.
Data Collection and Processing
Triage time and location were recorded for each patient, as well as time to physician assessment and time to a monitored bed. The door-to-ECG time was obtained from the electronic time stamp on each ECG. Research staff contacted patients and primary care physicians by telephone to review medications, as well as subsequent physician and hospital visits within 30 days. Test results (additional ECGs and cardiac biomarkers, provocative testing, and angiography) were recorded for the 30-day follow-up period. If patient contact was unsuccessful, any available records from regional hospitals were reviewed to establish or refute a 30-day diagnosis of acute coronary syndrome. Furthermore, the study list was linked to the British Columbia Death Registry to identify individuals who died within the 30-day period. All data were collected on specific study forms and entered into an Oracle database (Oracle Corporation, Redwood City, CA).
Outcome Measures and Primary Data Analysis
The primary outcome was the rate of missed acute coronary syndrome at 30 days in both groups. To establish a diagnosis of acute coronary syndrome, the investigators used predetermined explicit criteria for (1) acute myocardial infarction, (2) definite unstable angina, (3) possible unstable angina, (4) no acute coronary syndrome but an adverse event, or (5) no acute coronary syndrome and no adverse event (see Figure 1 for outcome definitions). In cases in which a diagnosis was unclear or could not be assigned, 2 blinded cardiologists independently reviewed the data and provided a diagnosis. If they could not reach an agreement, the principal investigator determined the outcome according to all available information, but blinded to treatment location (waiting room versus monitored bed). For the purpose of the primary outcome, acute coronary syndrome was defined as acute myocardial infarction or definite unstable angina. Patients discharged from their index ED visit with no acute coronary syndrome diagnosis and no acute coronary syndrome-specific follow-up arranged (ie, cardiology consultation or outpatient stress testing) and who proved to have an acute coronary syndrome diagnosis within 30 days were considered missed cases. Secondary outcomes were prespecified adverse events occurring in the ED (Figure 2). No monitoring was available in the waiting room, and adverse events were based on the need for physician intervention, rather than a physiologic standard. Tertiary outcomes included time to physician, cardiology consultations, and admission rate, and hospital length of stay, each stratified by cohort. Descriptive statistics, including proportions, medians, means and standard deviations, and confidence intervals (CIs), are reported as appropriate. No statistical tests of comparison are used because the differences between the 2 groups (with 95% CIs) are reported. SPSS (SPSS, Inc., Chicago, IL) was used for all group differences, except for nonparametric differences, which were calculated with a Hodges-Lehmann approach (cendif command, somersd package; Stata 9; StataCorp, College Station, TX).
Figure 1.
Outcome definitions.
Figure 2.
Adverse events.
Results
During the study period, 1,150 patients were enrolled, with complete 30-day follow-up obtained for 1,107 (96.3%). Of these, 804 patients were triaged to a monitored bed and 303 assigned to the waiting room. In the waiting room group, 102 (33.7%) patients never received an ED stretcher throughout their entire ED stay. Overall, 10.6% of patients had a 30-day diagnosis of acute coronary syndrome, including 11.7% in the monitored bed group (94/804) and 7.9% in the waiting room group (23/303).
Figure 3 illustrates patient enrollment and Table 1 summarizes baseline characteristics for the 2 groups. The waiting room group was younger and had a lower rate of emergency medical services (EMS) arrival and a lower prevalence of hypertension and previous acute coronary syndrome. Although initial vital signs were similar between groups, the proportion of patients with an abnormal initial ECG result (either ST-segment deviation or T-wave inversion) was higher in the monitored bed group. Although the time to physician assessment was slightly longer in the monitored bed group, the door-to-ECG time was longer in the waiting room group (51 versus 37 minutes).
Figure 3.
Patient enrollment. AMA, Against medical advice.
Table 1. Baseline characteristics.
| Characteristics | Monitored Bed | Waiting Room | Difference (95% CI)⁎ |
|---|---|---|---|
| Number of patients | 804 | 303 | |
| Age, y, mean (SD) | 56.6 (15.1) | 49.7(14.8) | 6.9(4.9to8.9) |
| Male sex, No. (%) | 488(60.7) | 172(56.7) | 3.9(–2.6to10.6) |
| EMS arrival, No. (%) | 260(32.3) | 60(20.0) | 12.3(6.6to18.0) |
| Ongoing chest pain at triage, No. (%) | 650(80.9) | 216(71.3) | 9.6(3.8to15.7) |
| Median time to physician,† min (IQR) | 28(17to46) | 25(12to45) | 3(2to4) |
| Median time to first ECG, min (IQR) | 37(27to57) | 51(21to73) | 14(12to16) |
| Mean initial pulse rate (SD) | 79.9(19.5) | 81.0(16.8) | 1.1(–1.2to3.4) |
| Mean initial systolic blood pressure, mm Hg (SD) | 142.7(26.6) | 140.6(24.8) | 2.1(–1.2to5.4) |
| Mean initial diastolic blood pressure, mm Hg (SD) | 79.3(14.1) | 81.2(13.8) | 1.9(0.0to3.8) |
| Mean initial respiratory rate, breaths/min (SD) | 18.6(3.3) | 18.0(2.0) | 0.6(0.3to0.9) |
| Initial abnormal ECG result, No. (%)‡ | 223(27.7) | 45(14.9) | 12.9(7.4to17.8) |
| Previous ACS, No. (%) | 224(27.9) | 41(13.5) | 14.4(9.1to19.0) |
| Smoker,† No. (%) | 250(31.1) | 101(33.3) | 2.2(–3.8to8.5) |
| Hypertension, No. (%) | 327(40.7) | 92(30.4) | 3.3(4.0to16.3) |
| Diabetes, No. (%) | 117(14.6) | 34(11.2) | 3.3(–1.3to7.4) |
| Hyperlipidemia, No. (%) | 235(29.2) | 66(21.8) | 7.5(1.4to13.0) |
⁎Continuity correction applied for differences between proportions. |
†Indicates that the proportion of waiting room patients exceeds the proportion of monitored bed patients. |
‡ST-segment deviation and T-wave inversion considered abnormal, regardless of conditions such as left ventricular hypertrophy or left bundle-branch block. T-wave flattening considered normal. |
Table 2 shows that no patient with acute coronary syndrome was inappropriately discharged with a mistaken non–acute coronary syndrome diagnosis in either group. The mortality rate was 0.5% in the monitored bed cohort (4/804) and 0% in the waiting room cohort. Table 3 displays adverse events. There were 32 (4.0%; 95% CI 2.6% to 5.3%) adverse events in the monitored bed cohort but only 2 (0.7%; 95% CI 0% to 1.6%) in the waiting room cohort, with no adverse events resulting in an unplanned admission.
Table 2. Diagnoses and outcome events, stratified by cohort.
| Results | Monitored Bed | Waiting Room | Difference⁎ (95% CI)† |
|---|---|---|---|
| Number of patients | 804 | 303 | |
| 30-day diagnosis, No. (%, 95% CI) | |||
| Acute myocardial infarction | 31(3.9) | 9(3.0) | 0.9(–1.9to3.0) |
| Definite unstable angina | 63(7.8) | 14(4.6) | 3.2(0.2to6.0) |
| Possible unstable angina | 19(2.4) | 4(1.3) | 1.0(–1.1to2.6) |
| No ACS but adverse event | 32(4.0) | 2(0.7) | 3.3(1.3to5.0) |
| No ACS and no adverse event | 659(82.0) | 274(90.4) | 8.5(3.7to12.6) |
| Number of ACS | 94(11.7) | 23(7.6) | 4.1(–0.2to7.6) |
| Missed cases of ACS, No. (%, 95% CI) | 0(0,0.0to0.4) | 0(0,0.0to1.0) | 0.0(–1.6to0.6) |
| Index visit outcome events, No. (%) | |||
| Death during index visit | 4(0.5) | 0(0.0) | 0.5(–1.1to1.4) |
| PCI during index visit‡ | 30(3.8) | 12(4.0) | 0.2(–2.2to3.5) |
| CABG during index visit | 15(1.9) | 1(0.3) | 1.5(–0.4to2.8) |
| 30-day outcome events, No. (%)§ | |||
| Death during 30-day follow-up | 4(0.5) | 0 | 0.5(–1.1to1.4) |
| PCI during 30-day follow-up | 40(5.0) | 13(4.3) | 0.7(–2.7to3.3) |
| CABG during 30-day follow-up | 19(2.4) | 2(0.6) | 1.7(–0.4to3.2) |
⁎Monitored bed group minus waiting room group. Indicates that proportion of waiting room group exceeds that of monitored bed group. |
†CI includes continuity correction. |
‡Indicates that the proportion of waiting room group exceeds that of monitored bed group. CI includes continuity correction. |
§All 30-day follow-up includes index visit. |
Table 3. ED adverse events stratified by cohort.
| Adverse Event, No. | Monitored Bed (%, 95% CI) | Waiting Room (%, 95% CI) | Difference (95% CI)⁎ |
|---|---|---|---|
| Number of patients | 804 | 303 | |
| Death in ED | 0(0,0to0.4) | 0(0,0to1.0) | 0(–1.6to0.6) |
| Chest compressions in ED | 0(0,0to0.4) | 0(0,0to1.0) | 0(–1.6to0.6) |
| Hypotension in ED | 1(0.1,0to0.2) | 0(0,0to1.0) | 0(–1.6to0.6) |
| Assisted ventilation in ED | 0(0,0to0.3) | 0(0,0to1.0) | 0(–1.6to0.6) |
| Tachyarrhythmia in ED | 29(3.6,2.3to4.9) | 2(0.7,0to1.6) | 2.9(0.7to4.6) |
| Bradyarrhythmia in ED | 2(0.2,0to0.4) | 0(0,0to1.0) | 0.2(–1.3to1.0) |
| New severe CHF in ED | 1(0.1,0to0.2) | 0(0,0to1.0) | 0(–1.6to0.6) |
| Total adverse events | 32(4.0,2.6to5.3) | 2(0.7,0to1.6) | 3.3(1.3to5.0) |
⁎Monitored bed group minus waiting room group. |
Table 4 describes diagnostic utilization and hospital resource use. Waiting room patients consumed fewer resources than their monitored bed counterparts. Although the proportion of patients receiving 0-hour ECGs was similar between groups, fewer waiting room patients received a 6-hour ECG or serial cardiac biomarker test. The waiting room group also had less outpatient provocative testing (exercise stress test or nuclear imaging) and fewer cardiology consultations. Although the proportion of patients receiving 0-hour ECGs was similar between groups, fewer waiting room patients received a 6-hour ECG or serial cardiac biomarker test. The waiting room group also had less outpatient provocative testing (exercise stress test or nuclear imaging) and fewer cardiology consultations.
Table 4. Diagnostic utilization and hospital resource use.⁎
| Utilization | Monitored Bed | Waiting Room | Difference (95% CI)⁎ |
|---|---|---|---|
| Number | 804 | 303 | |
| Diagnostic test at index visit, No. (%) | |||
| 0-h ECG performed | 798(99.3) | 293(96.7) | 2.5(0.7to5.4) |
| 6-h ECG performed | 327(40.7) | 91(30.1) | 10.6(4.1to16.8) |
| 0-h cardiac biomarker performed | 691(86.0) | 223(73.6) | 12.3(6.9to18.2) |
| 6-h cardiac biomarker performed | 368(45.8) | 118(38.9) | 6.8(0.1to13.3) |
| Provocative testing† at index ED visit | 10(1.2) | 2(0.7) | 0.6(–1.4to1.8) |
| Provocative testing† within 30 days | 188(23.3) | 64(21.1) | 2.2(–3.6to7.6) |
| ED cardiology consultation | 215(26.7) | 54(17.8) | 8.9(3.2to14.1) |
| Hospital utilization | |||
| Patients discharged within 3 h, No. (%) | 138(17.2) | 85(28.0) | 10.9(5.2to16.9) |
| Admission during index visit, No. (%)‡ | 158(19.7) | 36(11.8) | 7.8(2.9to12.0) |
| Admission during 30-day follow-up | 200(24.9) | 39(12.9) | 12.0(6.9to16.9) |
⁎Difference=proportion in the monitored bed group to proportion in the waiting room group. |
†Provocative testing=exercise treadmill test or stress myocardial perfusion imaging. Outpatient provocative testing typically took place within 48 hours. Admission: 21 patients who were initially discharged from the ED at the index visit were subsequently admitted for unstable angina after a positive outpatient stress ECG or radionuclide scan result. |
‡Differences indicate a higher proportion in the waiting room group than the monitored bed group. Continuity correction was used for the CI. |
Limitations
This is a comparative cohort study and has inherent limitations related to baseline differences between groups. Although the study design was not ideal, it would be impossible and unethical to conduct a clinical trial randomizing chest pain patients to monitored stretchers or waiting room chairs. Case-matching patients by age and sex would ignore the preassessment probability of acute coronary syndrome. An important potential weakness is that study subjects were identified according to a chief complaint of chest pain; therefore, acute coronary syndrome patients with weakness, dyspnea, or other ischemic symptoms may have been excluded. As a result, these findings cannot be generalized to acute coronary syndrome patients with atypical presentations. Third, because our 30-day outcomes were based on subsequent patient events and investigations, clinically occult events that did not lead to further investigation, repeated ED visits, hospitalization, or death would have been missed. Fourth, we did not collect morbidity measures such as new episodes of heart failure or quality of life indicators, nor did we evaluate patient satisfaction with comfort and privacy, which may be important concerns.32, 33 Finally, this is a single-center study at a tertiary care ED, and the external validity of such an approach is uncertain.
Despite these limitations, the prospective nature of this study and its intensive 30-day follow-up strategy are strengths. A validated triage tool was the primary decision instrument for patient placement. Inclusive yet rigorous eligibility criteria ensured that the greatest possible range of patients with potentially ischemic chest pain was enrolled. This study used explicit a priori definitions of outcomes and clinically relevant adverse events.
Discussion
The current study demonstrates no cases of missed acute coronary syndrome in a cohort of chest pain patients evaluated in an ED waiting room. Even at the upper confidence boundary, the proportion of missed cases is less than that in previous reports.25, 26 According to our predefined outcomes, only 2 adverse events occurred in the waiting room cohort; both were episodes of atrial fibrillation, with no objective evidence of cardiac ischemia. Both patients obtained a monitored bed at the earliest convenience, underwent uneventful electrical cardioversion, and were discharged from the ED, with no patient morbidity.
Median times to physician assessment were similar, at 25 minutes (interquartile range [IQR] 12 to 45 minutes) in the waiting room group and 28 minutes (IQR 17 to 48 minutes) in the monitored bed group; however, because waiting room evaluation of chest pain patients is a surge strategy and proxy marker for ED crowding, it is likely that chest pain patients would have waited substantially longer in the absence of a waiting room assessment option. Door-to-ECG times were 37 minutes (IQR 27 to 57 minutes) in the monitored bed group and 50 minutes (IQR 31 to 73 minutes) in the waiting room. Times to physician and times to ECG exceeded targets for both groups, but failure to achieve these standards did not appear to cause deleterious outcomes in our study.
Despite identical triage codes, waiting room patients had lower acute coronary syndrome rates, less diagnostic testing, lower admission rates, and shorter lengths of stay. Of the 303 patients initially triaged to the waiting room, one third (102) never obtained a formal ED stretcher. Our finding that no patients had an important adverse event related to waiting room care suggests that our triage system, combined with rapid clinical evaluation, can identify a subgroup of chest pain patients who do not require continuous cardiac monitoring and that limited ED resources can be diverted to patients with greater need and at higher clinical risk. This finding raises questions about the standard practice of placing all patients with possible cardiac pain chest in monitored care spaces. Although this practice may be preferred in the absence of crowding and when monitored care spaces are plentiful, it may lead to misallocation of ED resources.
Although the care of chest pain patients in nontraditional areas has not been studied, it is clear that ED crowding and related waiting room delays are linked to higher adverse event rates.34 In a recent study of 3,088 patients with ST-segment elevated myocardial infarction, Atzema et al35 ascertained that nearly half had been assigned a less urgent triage code, with resultant delays in door-to-needle time. Using ambulance diversion as a proxy for ED crowding, Schull et al21 documented delays to thrombolysis during periods of greater crowding. A 2007 study showed that adherence to American College of Cardiology/American Heart Association guidelines for patients with unstable angina deteriorated during ED crowding, although mortality rates were unaffected.36 All of these studies suggest that crowding and prolonged waiting room delays are associated with compromised care for patients with chest pain and acute coronary syndromes; however, no previous studies have described mitigating strategies for crowded EDs.
This study is not intended to demonstrate that assessment of patients with potential cardiac ischemia in the waiting room is ideal. It does, however, suggest that this is a feasible contingency strategy to mitigate adverse outcomes related to care delays. The relative benefit of such a strategy will depend on the degree of crowding experienced by a department. In this case, 27.4% (303/1,107) of patients with chest pain arrived when a traditional bed was not available.
The current study demonstrates that, with a rigorous triage system, rapid physician evaluation of chest pain patients before stretcher placement is feasible and may facilitate earlier assessment and more precise stratification of patient risk and ED care requirements. In addition, it may enable earlier recognition of patients who require critical intervention in the waiting room environment versus those who can be safely evaluated without the need for cardiac monitoring and acute stretcher placement. However, waiting room assessment of chest pain patients may compromise patient comfort and privacy and contravenes current evaluation guidelines. Further work is required to clarify which patients are safe to assess and treat in a nontraditional setting and identify optimal systems and processes for doing so.
An organized approach to triage and waiting room assessment for stable chest pain patients may be safe and efficient. Although waiting room evaluation is not ideal, it is a feasible contingency strategy for periods when ED crowding or volume surges lead to compromised access and delays to stretcher placement.
The authors thank Crystal-Ann Smith, RN, and Helen Xu, MD, for their dedication to this project.
References
- . Hospital-Based Emergency Care: At the Breaking Point. Washington, DC: National Academy Press; 2006;Executive summary http://www.nap.edu/catalog/11621.htmlAccessed July 13, 2009
- . Crisis in the emergency department. N Engl J Med. 2006;28:1300–1303
- . The etiology of medical gridlock: causes of emergency department overcrowding in New York City. J Emerg Med. 1990;8:785–790
- Emergency departments and crowding in United States teaching hospitals. Ann Emerg Med. 1991;20:890–986
- . How we solved the overcrowding problem in our emergency department. CMAJ. 1989;140:273–276
- . Increased health care costs associated with ED overcrowding. Am J Emerg Med. 1994;2:265–266
- . Overcrowding in the nation's emergency departments: complex causes and disturbing effects. Ann Emerg Med. 2000;35:63–68
- . Emergency department overcrowding in the United States: an emerging threat to patient safety and public health. Emerg Med J. 2003;20:402–405
- Frequency, determinants, and impact of overcrowding in emergency departments in Canada: a national survey. Healthc Q. 2007;10:32–40
- . Systemic review of emergency department crowding: causes, effects, and solutions. Ann Emerg Med. 2008;52:126–136
- Emergency department crowding: concepts, causes, effects and solutions. Ann Emerg Med. 2009;53:612–617
- The effect of emergency department crowding on clinically oriented outcomes. Acad Emerg Med. 2009;16:1–10
- Effect of emergency department crowding on time to antibiotics in patients admitted with community-acquired pneumonia. Ann Emerg Med. 2007;50:501–509
- The impact of emergency department crowding measures on time to antibiotics for patients with community acquired pneumonia. Ann Emerg Med. 2007;50:510–516
- . Emergency department crowding is associated with poor care for patients with severe pain. Ann Emerg Med. 2008;51:1–5
- Prolonged emergency department stays of non-ST-segment-elevation myocardial infarction patients are associated with worse adherence to the American College of Cardiology/American Heart Association guidelines for management and increased adverse events. Ann Emerg Med. 2007;50:489–496
- The association between emergency department crowding and hospital performance on antibiotic timing for pneumonia and percutaneous intervention for myocardial infarction. Acad Emerg Med. 2006;13:873–878
- . Increase in patient mortality at 10 days associated with emergency department overcrowding. Med J Aust. 2006;184:213–216
- The association between hospital overcrowding and mortality among patients admitted via Western Australian emergency departments. Med J Aust. 2006;184:208–212
- . Clinical review: emergency department overcrowding and the potential impact on the critically ill. Crit Care. 2005;9:291–295
- Emergency department crowding and thrombolysis delays in acute myocardial infarction. Ann Emerg Med. 2004;44:577–585
- . ED utilization and hospital discharge data: National Hospital Ambulatory Medical Care Survey. http://www.cdc.gov/nchs/data/ad/ad358.pdf.2002Accessed July 13, 2009
- ACC/AHA 2007 guidelines for the management of patients with unstable angina/non-ST-elevation myocardial infarction: executive summary (A report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines). Circulation. 2007;116:803–877
- Management of acute coronary syndromes (ACS) in patients presenting without persistent ST-segment elevation (European Society of Cardiology 2007). http://www.escardio.org/guidelines-surveys/esc-guidelines//Pages/ACS-non-ST-segment-elevation.aspxAccessed April 9, 2009
- Missed diagnoses of acute cardiac ischemia in the emergency department. N Engl J Med. 2000;342:1163–1170
- Safety and efficiency of emergency department assessment of chest discomfort. CMAJ. 2004;170:1803–1807
- Malpractice claims against emergency physicians in Massachusetts 1975-1993. Am J Emerg Med. 1996;14:341–345
- Emergency physicians' fear of malpractice in evaluating patients with possible acute cardiac ischemia. Ann Emerg Med. 2005;46:525–533
- Reliability of the Canadian Emergency Department Triage and Acuity Scale: interrater agreement. Ann Emerg Med. 1999;34:155–159
- . Inter-observer agreement using the Canadian Emergency Department Triage and Acuity Scale. CJEM. 2002;4:16–22
- Assessment of inter-observer reliability of two five-point triage and acuity scales: a randomized controlled trial. CJEM. 2004;6:240–245
- . Privacy and confidentiality in emergency medicine: obligations and challenges. Emerg Med Clin North Am. 2006;24:633–656
- From Hippocrates to HIPAA: privacy and confidentiality in emergency medicine—part 1: conceptual and legal foundations. Ann Emerg Med. 2006;45:53–59
- The association between emergency department crowding and adverse cardiovascular outcomes in patients with chest pain. Acad Emerg Med. 2009;16:617–625
- Emergency department triage of acute myocardial infarction patients and the effect on outcomes. Ann Emerg Med. 2009;53:736–745
- Prolonged emergency department stays of non-ST-segment elevation myocardial infarction patients are associated with worse adherence to the American College of Cardiology/American Heart Association guidelines for management and increased adverse events. Ann Emerg Med. 2007;50:489–496
Supervising editor: David L. Schriger, MD, MPH
Author contributions: FXS and JC conceived the study and designed the trial. JC, GI, BB, and EG supervised the conduct of the trial and data collection. BB and EY managed the database. FXS provided statistical analysis and drafted the article. All authors contributed substantially to its revision. FXS takes responsibility for the paper as a whole.
Funding and support: By Annals policy, all authors are required to disclose any and all commercial, financial, and other relationships in any way related to the subject of this article that might create any potential conflict of interest. The authors have stated that no such relationships exist. See the Manuscript Submission Agreement in this issue for examples of specific conflicts covered by this statement.
Publication date: Available online May 23, 2010.
Earn CME Credit: Continuing Medical Education is available for this article at: www.ACEP-EMedHome.com.
See page 456 for the Editor's Capsule Summary of this article.
Provide feedback on this article at the journal's Web site, www.annemergmed.com.
PII: S0196-0644(10)00350-1
doi:10.1016/j.annemergmed.2010.03.043
© 2010 American College of Emergency Physicians. Published by Elsevier Inc. All rights reserved.
