Emergency Department Patient Volume and Troponin Laboratory Turnaround Time

Abstract

Objectives: Increases in emergency department (ED) visits may place a substantial burden on both the ED and hospital-based laboratories. Studies have identified laboratory turnaround time (TAT) as a barrier to patient process times and lengths of stay. Prolonged laboratory study results may also result in delayed recognition of critically ill patients and initiation of appropriate therapies. The objective of this study was to determine how ED patient volume itself is associated with laboratory TAT.Methods: This was a retrospective cohort review of patients at five academic, tertiary care EDs in the United States. Data were collected on all adult patients seen in each ED with troponin laboratory testing during the months of January, April, July, and October 2007. Primary predictor variables were two ED patient volume measures at the time the troponin test was ordered: 1) number of all patients in the ED ⁄ number of beds (occupancy) and 2) number of admitted patients waiting for beds ⁄ beds (boarder occupancy). The outcome variable was troponin turnaround time (TTAT). Adjusted covariates included patient characteristics, triage severity, season (month of the laboratory test), and site. Multivariable adjusted quantile regression was carried out to assess the association of ED volume measures with TTAT.Results: At total of 9,492 troponin tests were reviewed. Median TTAT for this cohort was 107 minutes (interquartile range [IQR] = 73-148 minutes). Median occupancy for this cohort was 1.05 patients (IQR = 0.78-1.38 patients) and median boarder occupancy was 0.21 (IQR = 0.11-0.32). Adjusted quantile regression demonstrated a significant association between increased ED patient volume and longer times to TTAT. For every 100% increase in census, or number of boarders over the number of ED beds, respectively, there was a 12 (95% confidence interval [CI] = 9 to 14) or 33 (95% CI = 24 to 42)-minute increase in TTAT.Conclusions: Increased ED patient volume is associated with longer hospital laboratory processing times. Prolonged laboratory TAT may delay recognition of conditions in the acutely ill, potentially affecting clinician decision-making and the initiation of timely treatment. Use of laboratory TAT as a patient throughput measure and the study of factors associated with its prolonging should be further investigated.ACADEMIC EMERGENCY MEDICINE 2010; 17:501-507 ª

‘Chest Pain Typicality’ in Suspected Acute Coronary Syndromes and the Impact of Clinical Experience

“…In contrast, evidence examining the value of typical symptoms in patients presenting with chest pain in the acute setting have demonstrated a poor correlation with the final diagnosis of acute coronary syndrome (3,(13)(14)(15)(16)(17)(18)(19). However, these studies have tended to either include patients with diagnostic ECG changes , focus on specific chest pain characteristics rather than overall typicality, or use M A N U S C R I P T A C C E P T E D ACCEPTED MANUSCRIPT 5 research nurses to extract this information. Although it is evident that unstructured clinical judgment or gestalt has an important role to play in the overall risk assessment of acute chest pain patients (20), the subjective interpretation of typicality of chest pain and the impact that clinical experience may have upon its diagnostic accuracy remain poorly understood.…”

“…In the remainder, distinguishing whether a patient presenting with chest pain has acute coronary syndrome or a non-acute coronary syndrome problem is difficult (3). While some alternative diagnoses become apparent using history alone, the ongoing diagnostic uncertainty in the remainder of patients has been shown to lead to emergency department overcrowding, higher levels of resource use and increased healthcare costs (4)(5)(6).…”

Turnaround Times for Hematology and Chemistry Tests in the Emergency Department: Experience of a Teaching Hospital in Iran

“…In 2007, Hawkins reported that the initial goal was to complete 90% of common laboratory tests within 60 minutes (2). In 2010, the median TAT for 9492 troponin tests was 107 minutes (range 73 -148 minutes) (15). In contrast, in an Indian laboratory, the mean TAT from sample reception to report was 5.5 hours for routine inpatient samples (4).…”

Seven Q-Tracks Monitors of Laboratory Quality Drive General Performance Improvement: Experience From the College of American Pathologists Q-Tracks Program 1999–2011

“…49 Emergency department physicians also sometimes argue that longer orderto-report troponin TATs slow patients' progress to the next steps in the clinical diagnostic process, including the critical next step of cardiac catheterization. 50,51 5. The more clearly defined defect of delay beyond the anticipated interval in STAT test results' receipt-to-report times stimulates more clinician dissatisfaction.…”

“…27,55 The clinical effect of report errors is also rare; it is easier to demonstrate for microbiology results that must be altered 55 but may also appear after erroneous chemistry results. 27,51 Rationale for the Q-Tracks Focus on Process Defects…”