The effect of physician risk tolerance and the presence of an observation unit on decision making for ED patients with chest pain

Abstract

Objectives

We sought to determine whether risk tolerance as measured by scales (malpractice fear scale [MFS], risk-taking scale [RTS], and stress from uncertainty scale [SUS]) is associated with decisions to admit or use computed tomography (CT) coronary angiogram and decisions to order cardiac markers in emergency department (ED) patients with chest pain. We also studied if the opening of an ED-based observation unit affected the relationship between risk scales and admission decisions.

Methods

Data from a prospective study of ED patients 30 years or older with chest pain were used. Risk scales were administered to ED attending physicians who initially evaluated them. Physicians were divided into quartiles for each separate risk scale. Fisher's exact test and logistic regression were used for statistical analysis.

Results

A total of 2872 patients were evaluated by 31 physicians. The most risk-averse quartile of RTS was associated with higher admission rates (78% vs 68%) and greater use of cardiac markers (83% vs 78%) vs the least risk-averse quartile. This was not true for MFS or SUS. Similar associations were observed in low-risk patients (Thrombolysis in Myocardial Infarction risk score of 0 or 1). The observation unit was not associated with a higher admission rate and did not modify the relationship between risk scales and admission rates.

Conclusion

The RTS was associated with the decision to admit or use computed tomography coronary angiogram, as well as the use of cardiac markers, whereas the MFS and SUS were not. The observation unit did not affect admission rates and nor did it affect how physician's risk tolerance affects admission decisions.

Introduction

Chest pain syndrome accounts for approximately 5.8 million annual emergency department (ED) visits in the United States [1]. Studies have estimated that between 2% and 6% of patients are initially discharged from an ED and are later found to have acute coronary syndrome (ACS) [2], [3], [4]. Missed ACS is associated with poorer outcomes and, among ED diagnoses, results in the highest dollar amount of malpractice litigation [5], [6]. Annual direct costs of patients admitted from the ED with a primary hospital discharge diagnosis of “chest pain, not otherwise specified,” are approximately $3.1 billion in the United States [7].

Factors associated with missed ACS patients include nonwhite race and normal electrocardiogram (ECG) results, as well as hospital-level factors such as low ED volume [2], [7], [8]. However, for the ED physician, these factors are not sufficiently specific to provide a basis for clinical decision making and merely confirm that ACS occurs in low-risk patients. In the absence of ED-based cardiac imaging (nuclear medicine, echocardiography, computed tomography coronary angiography [CTCA], or cardiac catheterization), results of traditional ED tests (electrocardiogram and cardiac markers) cannot completely rule out ACS [9], [10], [11], [12]. Therefore, a large proportion of patients are admitted to the hospital, but in most patients, ACS is ruled out [13]. The 2007 American College of Cardiology/American Heart Association Guidelines for the Management of Patients With Unstable Angina/Non ST-Elevation Myocardial Infarction support this concept and do not specify clinical criteria for the identification of low-risk patients who can safely be discharged without definitive testing [14]. Therefore, admission decisions are primarily made based upon the treating physician's assessment of the patient's risk and the testing available in the ED. Previous studies have demonstrated that a physician's perception of risk and malpractice fear may also influence clinical decision making [15], [16]. Variations in physician practice based on differences in risk tolerance may lead to suboptimal care and inefficient use of resources.

We sought to extend the understanding in this area by testing the association between 3 validated scales (stress due to uncertainty, physician risk taking, and malpractice fear) and decisions by attending physicians to admit and order cardiac markers on ED patients with chest pain syndrome. Second, we studied whether the introduction of an observation was associated with changes in the decision to admit or use of definitive cardiac testing (CTCA) and if the presence of an observation unit modified the relationship between risk scales and this decision.