Managing unstable angina and coronary care beds effectively

Impact of a decision rule on duration of continuous cardiac monitoring of patients with suspected acute coronary syndrome in an emergency department

BACKGROUND/AIMS

To determine the effect of introducing a decision rule on the duration of continuous cardiac monitoring (CCM) for patients with suspected acute coronary syndrome in an adult emergency department (ED).

METHODS

This was a retrospective observational study of 220 patients with suspected acute coronary syndrome made up of two consecutive cohorts collected before and after introduction in July 2010 of a decision rule that made use of a new high-sensitivity troponin T assay. The primary outcome was median CCM duration in the ED (CCMED). Secondary outcomes were median duration of CCM in the first 24 h, rate of adverse events, proportion of patients after the intervention who had the rule adhered to, and estimated median CCMED had the decision rule been adhered to by all patients.

RESULTS

The decision rule was adhered to in 59.3% (95% confidence interval 49.8-68.1) of patients post-intervention. There was no statistically or clinically significant difference in median CCMED before (240 min, interquartile range 156-313) and after (230 min interquartile range 145-353) introduction of the decision rule (P = 0.74) nor in CCM in the first 24 h (908 min vs 929 min). Seven (3.2%, 95% confidence interval 1.4-6.6) adverse events occurred overall. All three patients with adverse events after the intervention were monitored in ED according to the decision rule.

CONCLUSION

Introduction of this decision rule did not decrease the median CCMED. All adverse events after the intervention occurred in appropriately monitored patients, including patients with initially negative high-sensitivity troponin T, suggesting that the decision rule would not compromise patient safety.

A clinical decision rule to identify which chest pain patients can safely be removed from cardiac monitoring in the emergency department

STUDY OBJECTIVE

We determine the rate of serious arrhythmias in a cohort of monitored emergency department (ED) chest pain patients and derive a clinical decision rule that can identify which patients can safely be taken off continuous cardiac monitoring at initial physician assessment.

METHODS

A secondary analysis of a prospectively collected cohort was completed in a university-affiliated tertiary care center. Consecutive patients with a primary complaint of chest pain who underwent cardiac monitoring in the ED in January to April 2000 were included. Serious arrhythmias were defined as those requiring treatment in the ED. Multivariate recursive partitioning analysis was undertaken to derive a decision rule.

RESULTS

Nine hundred ninety-two consecutive chest pain patients were monitored in the ED during the study period, of whom 14% and 12% had myocardial infarction and unstable angina, respectively. There were 17 patients (1.7%) with serious arrhythmias detected in the ED. The following decision rule was derived: patients can be removed from cardiac monitoring if they are pain free at the initial physician assessment and have a normal or nonspecific ECG result. The rule had 100% sensitivity (95% confidence interval 80% to 100%) for serious arrhythmias. Applying this rule would have allowed physicians to immediately remove 29% of patients from cardiac monitoring.

CONCLUSION

Serious arrhythmias are uncommon in monitored ED chest pain patients. A simple clinical decision rule could be used to safely identify low-risk patients who can be removed from continuous monitoring if its performance is prospectively validated in an independent patient population.

Clinical features in the emergency department can identify patients with suspected acute coronary syndromes who are safe for care in unmonitored hospital beds

BACKGROUND

Standard practice for patients requiring hospital admission with suspected acute coronary syndromes (ACS) is admission to a monitored cardiology bed. The Western Hospital Chest Pain Protocol was developed to identify a subset of these patients who could be safely managed in an unmonitored bed.

AIM

The objective of this prospective study of chest pain patients classified as 'high' or 'intermediate' risk by the Agency for Health Care Policy and Research/National Health and Medical Research Council guidelines was to further evaluate the safety of this protocol.

METHODS

This study was a prospective, observational, cohort study investigating the outcomes of patients admitted to hospital with suspected ACS. The primary outcome of interest was death or life-threatening arrhythmia within 24 h of hospital admission.

RESULTS

If the Western Hospital Chest Pain Protocol had been strictly applied, there would have been one death in the group assigned to unmonitored beds (1/750; 0.13%, 95% confidence interval 0.01-0.85%) and no other life-threatening arrhythmias.

CONCLUSION

There is a subgroup of patients with suspected ACS who require hospital admission who can, based on clinical and biochemical features in the emergency department, be safely assigned to unmonitored beds.

Validation of a tool to safely triage selected patients with chest pain to unmonitored beds

OBJECTIVE

To externally validate a chest pain protocol that triages low risk patients with chest pain to an unmonitored bed.

METHODS

Retrospective study of all patients admitted from the emergency department of a tertiary referral public teaching hospital with an admission diagnosis of 'unstable angina' or suspected ischemic chest pain. Data was collected on adverse outcomes and analysed on the basis of intention-to-treat according to the chest pain protocol.

RESULTS

There were no life-threatening arrhythmias, cardiac arrests or deaths within the first 72 h of admission in the group assigned to an unmonitored bed by the chest pain protocol ([0/244]; 0.0%: 95% confidence interval 0.0-1.5%). Four patients had an uncomplicated myocardial infarction, two patients had recurrent ischemic chest pain and one patient developed acute pulmonary oedema ([7/244]; 2.9%: 95% confidence interval 1.2-5.8%).

CONCLUSION

This retrospective study externally validated the chest pain protocol. Care in a monitored bed would not have altered outcomes for patients triaged to an unmonitored bed by the chest pain protocol. Compared to current guidelines, application of the chest pain protocol could increase the availability of monitored beds.

It is safe to manage selected patients with acute coronary syndromes in unmonitored beds

This prospective, observational study evaluated the safety of the Western Hospital admission protocol for patients with suspected acute coronary syndromes. The study included all patients admitted from the Emergency Department with an admission diagnosis of unstable angina, post infarct angina, atypical chest pain, or chest pain for evaluation. Data collected included demographic data, admission diagnosis, location of admission (bed with or without cardiac monitoring), past medical history and presenting chest pain history to determine Agency for Health Care Policy (AHCPR) and Western Hospital (WH) protocol classifications, cardiac enzyme assays, electrocardiogram analysis, adverse outcomes [death, myocardial infarction (MI), dysrhythmia, acute pulmonary edema, recurrent pain], diagnosis at hospital discharge, and length of stay-(LOS). There were 508 patients with a mean age of 63.7 years enrolled in the study. Three hundred nineteen (62.8%) were admitted to beds without any cardiac monitoring. There was one unexpected death in the unmonitored group, an 85 year-old patient who suffered a presumed dysrhythmia and whom the treating physician had decided was not for resuscitation. Twelve patients suffered nonfatal MI, and none suffered pulmonary edema. All MI patients made an uneventful recovery, and none required thrombolysis. If all patients had been admitted to an area of care based on AHCPR guidelines, an additional 310 admissions to monitored beds would have been required. The results of this study suggest that selected patients with suspected acute coronary syndromes can be safely managed in beds without continuous cardiac monitoring.