Potential Impact of Adjusting the Threshold of the Quantitative D‐dimer Based on Pretest Probability of Acute Pulmonary Embolism

Kabrhel, Christopher; Courtney, D. Mark; Camargo, Carlos A.; Moore, Christopher L.; Richman, Peter B.; Plewa, Michael C.; Nordenholtz, Kristen; Smithline, Howard; Beam, Daren M.; Brown, Michael D.; Kline, Jeffrey A.

doi:10.1111/j.1553-2712.2009.00368.x

Cited by 42 publications

(33 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Several studies have compared clinical gestalt assessment to the Wells score and have found comparable results in assessing pretest probability. 19–21 Moreover, some clinicians may err on the side of ordering unnecessary CT-PA in low-risk patients for fear of litigation. Runyon et al demonstrated that only half of physicians who are familiar with commonly used clinical decision rules use them in more than half of appropriate patients.…”

Section: Discussionmentioning

confidence: 99%

Overuse of Computed Tomography Pulmonary Angiography in the Evaluation of Patients with Suspected Pulmonary Embolism in the Emergency Department

Crichlow

Cuker

Mills

2012

Academic Emergency Medicine

View full text Add to dashboard Cite

Background Clinical decision rules have been developed and validated for the evaluation of patients presenting with suspected pulmonary embolism (PE) to the emergency department (ED). Objectives To assess the percentage of computed tomographic pulmonary angiography (CT-PA) which could have been avoided by use of the Wells score coupled with D-dimer testing (Wells/D-dimer) or Pulmonary Embolism Rule-Out Criteria (PERC) in ED patients with suspected PE. Methods The authors conducted a prospective cohort study of adult ED patients undergoing CT-PA for suspected PE. Wells score and PERC were calculated. A research blood sample was obtained for D-dimer testing for subjects who did not undergo testing as part of their ED evaluation. The primary outcome was PE by CT-PA or 90-day follow-up. Secondary outcomes were ED length of stay (LOS) and CT-PA time as defined by time from order to initial radiologist interpretation. Results Of 152 suspected PE subjects available for analysis (mean age 46.3±15.6 years, 74% female, 59% black or African American, 11.8% diagnosed with PE), 14 (9.2%) met PERC, none of whom were diagnosed with PE. A low-risk Wells score (≤4) was assigned to 110 (72%) subjects, of whom only 38 (35%) underwent clinical D-dimer testing (elevated in 33/38). Of the 72 subjects with low-risk Wells scores who did not have D-dimers performed in the ED, archived research samples were negative in 16 (22%). All 21 subjects with low-risk Wells scores and negative D-dimers were PE-negative. CT-PA time (median 160 minutes) accounted for more than half of total ED LOS (median 295 minutes). Conclusions In total, 9.2% and 13.8% of CT-PA could have been avoided by use of PERC and Wells/D-dimer, respectively.

show abstract

Section: Discussionmentioning

confidence: 99%

Overuse of Computed Tomography Pulmonary Angiography in the Evaluation of Patients with Suspected Pulmonary Embolism in the Emergency Department

Crichlow

Cuker

Mills

2012

Academic Emergency Medicine

View full text Add to dashboard Cite

show abstract

“…123, 124 Our study makes no assumption about the “correct” frequency of D-dimer use. D-dimer use is explicitly considered in the model through the estimation of costs and health outcomes for different D-dimer cutoffs in the setting of different Wells patient categories.…”

Section: Discussionmentioning

confidence: 99%

Cost-Effectiveness of Strategies for Diagnosing Pulmonary Embolism Among Emergency Department Patients Presenting With Undifferentiated Symptoms

Duriseti

Brandeau

2010

Annals of Emergency Medicine

View full text Add to dashboard Cite

Objective Symptoms associated with pulmonary embolism (PE) can be nonspecific and similar to many competing diagnoses, leading to excessive costly testing and treatment as well as missed diagnoses. Objective studies are essential for diagnosis. This study evaluates the cost-effectiveness of different diagnostic strategies in an Emergency Department (ED) for patients presenting with undifferentiated symptoms suggestive of PE. Methods Using a probabilistic decision model, we evaluated the incremental costs and effectiveness (quality-adjusted life years (QALYs) gained) of 60 testing strategies for five patient pretest categories (distinguished by Wells score (High, Moderate, or Low) and whether deep venous thrombosis (DVT) is clinically suspected). We performed deterministic and probabilistic sensitivity analyses. Results In the base case, for all patient pretest categories, the most cost-effective diagnostic strategy is to use an initial ELISA D-dimer test, followed by compression ultrasound (CUS) of the lower extremities if the D-dimer is above a specified cutoff. The level of the preferred cutoff varies with the Wells pretest category and whether a DVT is clinically suspected. D-dimer cutoffs higher than the current recommended cutoff were often preferred for even Moderate and High Wells category patients. CUS accuracy had to fall below commonly cited levels in the literature before it was not part of a preferred strategy. Conclusions When PE is suspected in the ED, use of an ELISA D-dimer assay, often at cutoffs higher than those currently in use (for patients in whom DVT is not clinically suspected), followed by CUS as appropriate, can reduce costs and improve outcomes.

show abstract

“…Using the combination of low clinical risk and higher d-dimer threshold could have prevented a CTA study in 1/3 of all patients. Kabrhel et al observed that for a large population of patients at low clinical risk for pulmonary embolism (prevalence of 2.9%), doubling the d-dimer threshold for any quantitive d-dimer assay resulted in a significant increase in specificity from 63% to 86% without a significant decrease in the negative predictive value (99.6% to 98.9%) [27].…”

Section: Discussionmentioning

confidence: 99%

Avoiding Unnecessary Pulmonary CT Angiography by Using a Combination of Clinical Criteria and D-Dimer Thresholds

Gimber¹,

Leong²,

Todoki³

et al. 2013

OJRad

View full text Add to dashboard Cite

Objective:To evaluate what specific combination of clinical criteria and d-dimer values may yield at least a 10% positive pulmonary embolism (PE) rate in patients undergoing pulmonary CT angiography (CTA). Materials and Methods: Retrospective review of all patients presenting to the Emergency Department with possible PE who underwent pulmonary CTA and had a d-dimer drawn. Wells scores were retrospectively assigned based on data gathered through medical records. Results: During a 29-month period, 1110 patients underwent pulmonary CTA. Of these, 773 also had a d-dimer drawn. These subjects were stratified based on serum d-dimer levels into negative (≤4 µg/ml), nonpositive (0.41 -1.0 µg/ml), or positive (>1.0 µg/ml) d-dimer categories. The prevalence of positive CTA studies was >10% only in the positive d-dimer group. Subjects were also stratified based on their Wells score into three clinical categories: low (score < 2), intermediate (score = 2 -6), and high risk of pulmonary embolism (score > 6). The prevalence of positive CTA was > 10% only in the group of subjects with high clinical risk. When stratified according to both Wells criteria and d-dimer, only those patients with intermediate or high clinical risk combined with a positive d-dimer (>1.0 µg/ml) had a prevalence of positive pulmonary CTA > 10%. By limiting the use of CTA studies to those patients with positive d-dimer values or high clinical risk, 438 (55.4%) patients could have avoided CTA imaging. Conclusion: Utilizing CTA only in patients suspected of PE with a combination of high clinical risk based on a Wells criteria threshold score > 6 and a serum d-dimer cutoff of 1 µg/ml would increase the prevalence of positive pulmonary CTA studies above 10% and avoid a large number of CTA imaging studies.

show abstract

Potential Impact of Adjusting the Threshold of the Quantitative D‐dimer Based on Pretest Probability of Acute Pulmonary Embolism

Cited by 42 publications

References 24 publications

Overuse of Computed Tomography Pulmonary Angiography in the Evaluation of Patients with Suspected Pulmonary Embolism in the Emergency Department

Overuse of Computed Tomography Pulmonary Angiography in the Evaluation of Patients with Suspected Pulmonary Embolism in the Emergency Department

Cost-Effectiveness of Strategies for Diagnosing Pulmonary Embolism Among Emergency Department Patients Presenting With Undifferentiated Symptoms

Avoiding Unnecessary Pulmonary CT Angiography by Using a Combination of Clinical Criteria and D-Dimer Thresholds

Contact Info

Product

Resources

About