The effect of vertical split-flow patient management on emergency department throughput and efficiency.

BACKGROUND: To address emergency department overcrowding operational research seeks to identify efficient processes to optimize flow of patients through the emergency department. Vertical flow refers to the concept of utilizing and assigning patients virtual beds rather than to an actual physical space within the emergency department to care of low acuity patients. The aim of this study is to evaluate the impact of vertical flow upon emergency department efficiency and patient satisfaction. METHODS: Prospective pre/post-interventional cohort study of all intend-to-treat patients presenting to the emergency department during a two-year period before and after the implementation of a vertical flow model. RESULTS: In total 222,713 patient visits were included in the analysis with 107,217 patients presenting within the pre-intervention and 115,496 in the post-intervention groups. The results of the regression analysis demonstrate an improvement in throughput across the entire ED patient population, decreasing door to departure time by 17 min (95% CI 15-18) despite an increase in patient volume. No statistically significant difference in patient satisfaction scores were found between the pre- and post-intervention. CONCLUSIONS: Initiation of a vertical split flow model was associated with improved ED efficiency.

An emergency department guideline for the diagnosis of pulmonary embolism: an outcome study.

OBJECTIVE: To assess the clinical outcome of patients suspected of pulmonary embolism (PE) following implementation of an emergency department (ED) diagnostic guideline. METHODS: A prospective observational study of all patients suspected of PE who presented to the ED during a four-month study period. The authors' modification of the Charlotte criteria recommended D-dimer testing in those younger than 70 years of age with a low clinical suspicion of PE and no unexplained hypoxemia, unilateral leg swelling, recent surgery, hemoptysis, pregnancy, or prolonged duration of symptoms. The primary outcome was the identification of venous thromboembolism during a three-month follow-up period. The negative predictive value of the overall diagnostic strategy and the test characteristics of D-dimer were calculated. RESULTS: A total of 1,207 consecutive patients were evaluated for suspected PE; 71 (5.8%) were diagnosed with venous thromboembolism. One missed case of PE was identified on follow-up, yielding a negative predictive value of 99.9% (95% confidence interval [CI] = 99.5% to 100%). The missed case was a patient who presented with pleuritic chest pain and shortness of breath; a chest radiograph revealed pneumothorax, and the physician decided not to pursue the positive D-dimer result. The patient returned six weeks later with PE. Subgroup analysis of patients having D-dimer performed (n = 677) yields a sensitivity of 0.93 (95% CI = 0.77 to 0.98) and a specificity of 0.74 (95% CI = 0.70 to 0.77). CONCLUSIONS: Implementation of a PE diagnostic guideline in a community ED setting is safe and has improved the specificity of the enzyme-linked immunosorbent assay D-dimer test when compared with previous studies.

Novel protein markers of acute coronary syndrome complications in low-risk outpatients: a systematic review of potential use in the emergency department.

BACKGROUND: Published literature was systematically reviewed to determine the diagnostic accuracy of new protein markers of acute coronary syndromes (ACS) in symptomatic outpatients at low risk of ACS and related complications comparable to patients evaluated in emergency department chest pain units. METHODS: Studies were identified by a MEDLINE (1966 to May week 3, 2005) search. Abstracts were reviewed for relevance, and manuscripts were included by the independent consensus of 2 observers based on explicit criteria restricting the analysis to studies relevant to screening ambulatory patients with symptoms suggesting ACS. Publication bias was identified by a modified funnel plot analysis [study size (y) vs the inverse of the negative likelihood ratio (x)]. Results of individual markers were reported separately. When 3 or more eligible studies were identified, data were aggregated by use of the summary ROC (SROC) curve. RESULTS: Twenty-two protein markers in 10 unique populations met the inclusion criteria. Data required for SROC analysis (true- and false-positive rates) were available for 17 markers, in 9 unique populations, from publications and personal communications. Of these, only C-reactive protein was published in more than 2 populations to allow aggregation (6 studies total). C-Reactive protein demonstrated poor diagnostic performance on SROC curve analysis, with an area under the curve of 0.61 and a pooled diagnostic odds ratio of 1.81 (95% confidence interval, 1.06-3.07). CONCLUSION: Published evidence is not sufficient to support the routine use of new protein markers in screening for ACS in the emergency department setting.

Turbidimetric D-dimer test in the diagnosis of pulmonary embolism: a metaanalysis.

BACKGROUND: Clinicians in outpatient clinics and emergency departments desire an accurate quantitative D-dimer assay. The study objective was to evaluate the diagnostic performance characteristics of the latex turbidimetric D-dimer test in the diagnosis of pulmonary embolism (PE) in the emergency department population. METHODS: We conducted a search of MEDLINE, EMBASE, and bibliographies of previous systematic reviews with no language restriction. Experts in the field of PE research were contacted to identify unpublished studies. Prospective investigations involving predominately outpatient populations with suspected PE that used a turbidimetric D-dimer test were included. Two authors extracted data independently and assessed study quality based on the composition of the patient spectrum and the reference standard used. Consensus was reached by conference. The analysis was based on a summary ROC curve and combining sensitivity and specificity independently across studies using a random-effects model. RESULTS: The search yielded 264 publications and 2 unpublished studies. Nine studies met the inclusion criteria and provided a sample of 1901 individuals. Eight of the nine studies were homogeneous in terms of both sensitivity and specificity. One study had similar sensitivity but higher specificity. Combining the studies yielded an overall sensitivity of 0.93 (95% confidence interval, 0.89-0.96) and an overall specificity of 0.51 (95% confidence interval, 0.42-0.59). CONCLUSIONS: The turbidimetric D-dimer test is sensitive but nonspecific for the detection of PE in the emergency department setting. D-Dimer tests using latex turbidimetric methods appear to have test characteristics comparable to those for ELISA methods.