Original contributionIt is safe to manage selected patients with acute coronary syndromes in unmonitored beds1
Introduction
In most Australian hospitals, it is the usual practice to admit patients suffering suspected acute coronary syndromes (ACS), such as unstable angina, to areas of care that have continuous cardiac monitoring such as coronary care units (CCU). The rationale for this approach is predicated on the assumption that the benefits afforded by cardiac monitoring to patients with myocardial infarction (MI) also apply to those with ACS. Although this assumption has not been confirmed by research, the requirement for cardiac monitoring for patients with suspected ACS has been reinforced by the Agency for Health Care Policy and Research (AHCPR, USA) and the National Health and Medical Research Council (Australia) guidelines on the management of unstable angina 1, 2. This practice places significant stress on a limited number of monitored beds, has proven to be costly, and may result in admission delays (or on occasion, transfer between hospitals) for patients with proven MI (3).
Recent studies from the United States have shown that a subgroup of patients with ACS can be safely managed in telemetry areas and have questioned the need for monitored beds for these patients (4).
In 1997, in response to problems accessing CCU beds and a high number of acute inter-hospital transfers caused by shortages of CCU beds, Western Hospital (WH) undertook a comprehensive, multi-disciplinary review of chest pain admission policies. This evidence-based review aimed to improve the efficiency of using monitored beds, to improve access to CCU beds for patients who had suffered MI, and to provide safe management for patients suffering unstable angina or other suspected ACS. The process and results of this protocol development have been reported previously 5, 6. The outcome was an admission protocol (WH protocol) that triaged selected patients with ACS considered at low risk of adverse events to care in ward beds without cardiac monitoring. Criteria for admission to an unmonitored bed are: pain that is relieved with glyceryl trinitrate (GTN) spray or tablet or morphine, a normal or unchanged electrocardiogram (EKG), and cardiac enzyme (CK/CKMB) level within the normal range at presentation to the Emergency Department (ED). Conversely, a patient who requires i.v. GTN for chest pain relief, who has an abnormal or changed EKG (defined as ST elevation or depression, T wave inversion or new conduction defect), or who has an elevated CK/CKMB level is admitted to the CCU. Although encouraged, the protocol is not enforced rigidly. Individual doctors may choose to assign patients to the CCU if they consider them to be at high risk.
The WH admission protocol is at odds with current international practice guidelines (1). The dichotomy between the WH protocol and AHCPR guideline lies in the management of patients with unstable angina, and more specifically, those who fall into the AHCPR intermediate classification. The AHCPR guidelines recommend these patients be admitted to monitored beds for a period of usually not less than 24 h, whereas the WH protocol triages many of these patients to unmonitored beds. It has been proposed that the classification system as proposed within the AHCPR guidelines needs to be validated, or invalidated, based on clinical data, as a means of refining and modifying the proposed model (7).
The objectives of this project were:
- 1.
To evaluate the safety of the WH admission protocol for patients with suspected ACS.
- 2.
To compare outcomes and resource use between the approach recommended by the AHCPR guidelines, “intention-to-treat” application of the WH protocol, and application of the WH protocol as occurred in reality.
Section snippets
Setting
Western Hospital is a 346-bed university teaching hospital located in Melbourne, Australia. The ED has an annual census of 36,000 adult patients with an admission rate of 40%. During the study period, the hospital had 12 monitored cardiology beds. The ED is staffed by six emergency physicians and 20 residents ranging in experience from PGY1 to PGY10. The majority of the residents are undertaking training toward specialization in Emergency Medicine. All shifts are supervised by an Emergency
Results
During the study period, 508 patients met the inclusion criteria, and all were entered in the study. For the same period, there were 22,446 presentations to the ED. There were 211 women and 297 men in the study group with an age distribution of 25 to 95 years (mean 63.7 years; median 64 years). Forty-three patients (9%) were classified as high risk by the AHCPR criteria, 449 (88%) as intermediate risk, and 16 (3%) as low risk.
Three hundred and nineteen patients (62.8%) were admitted to ward
Discussion
In most Australian hospitals, it is usual to admit patients suffering suspected ACS to monitored beds in, for example, the CCU or stepdown areas. The benefit of this practice has not been confirmed by research but has been reinforced by the AHCPR and NHMRC guidelines on the management of unstable angina. This practice places significant stress on a limited number of monitored beds, is costly, and may result in delays to admission (or, on occasion, a requirement for transfer between hospitals)
Conclusion
The results of this study suggest that selected patients with suspected ACS can be safely managed in beds without continuous cardiac monitoring.
Acknowledgements
The authors would like to thank Dr. Robert Newman, and Mrs. Liz Edmonds for their assistance in protocol development and implementation.
References (32)
- et al.
Validation of the agency for health care policy and research (AHCPR) classification for managing unstable angina
J Clin Epidemiol
(1999) - et al.
Risk of adverse outcome in patients admitted to the coronary care unit with suspected unstable angina pectoris
Am J Cardiol
(1989) - et al.
Unstable anginanatural history and determinants of prognosis
Am J Cardiol
(1981) - et al.
Outcome in suspected acute myocardial infarction with normal or minimally abnormal admission electrocardiographic findings
Am J Cardiol
(1987) - et al.
Prognostic value of the emergency department cardiogram for in-hospital complications of acute myocardial infarction
Ann Emerg Med
(1993) - et al.
Early prediction of acute myocardial infarction from clinical history, examination and electrocardiogram in the emergency room
Am J Cardiol
(1991) - et al.
Are monitored telemetry beds necessary for patients with nontraumatic chest pain and normal or nonspecific electrocardiograms
Am J Cardiol
(1997) - et al.
Do patient’s coronary risk factor reports predict acute cardiac ischemia in the emergency department? A Multicentre Study
J Clin Epidemiol
(1992) - et al.
Evaluation and risk stratification of patients with chest pain in the emergency department
Emerg Med Clin North Am
(1998) - et al.
Implementation of serum cardiac troponin I as a marker for detection of acute myocardial infarction
Am Heart J
(1999)
Evaluation of chest pain in low-risk patients presenting to the emergency departmentthe role of immediate exercise testing
Ann Emerg Med.
Performance and potential impact of a chest pain prediction rule in a Large Public Hospital
Am J Med
Diagnosis and management of unstable angina. Clinical practice guidelines
The use of empiric clinical data in the evaluation of practice guidelines for unstable angina
JAMA
The continuing search to identify the very-low-risk chest pain patient
Acad Emer Med
Cited by (0)
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Original Contributions is coordinated by John A. Marx, md, of Carolinas Medical Center, Charlotte, North Carolina