Accuracy of combining clinical probability score and simpliRED D-dimer for diagnosis of pulmonary embolism
Date First Published:
August 9, 2001
Last Updated:
July 1, 2003
Report by:
Russell Boyd, Consultant in Emergency Medicine (Lyell McEwin Health Services Adelaide)
Search checked by:
Kerstin Hogg, Lyell McEwin Health Services Adelaide
Three-Part Question:
In [suspected PE] is [bedside clinical examination and simpliRED D-dimer sufficiently sensitive] at [ruling out PE]?
Clinical Scenario:
A 34 year old woman presents with a 2 day history of pleuritic chest pain. There are no abnormal physical signs and her only risk factor is that she is taking the oral contraceptive pill long term. You wonder if a combination of clinical examination and the available d-dimer test (SimpliRED) would be suitable to rule out pulmonary embolism.
Search Strategy:
Medline 1966-04/03 using the OVID interface.
Search Details:
[D-dimer.mp OR simplired.mp OR whole blood.mp] AND [exp thromboembolism OR exp pulmonary embolism OR PE.mp OR pulmonary embol$.mp OR pulmonary infarct$.mp] AND [exp"sensitivity and specificity".mp OR sensitivity.tw OR di.xs OR du.fs OR specificity.tw] LIMIT to human AND English.
Outcome:
Altogether 272 papers were identified of which 5 were relevant and of sufficient quality.
Relevant Paper(s):
| Study Title | Patient Group | Study type (level of evidence) | Outcomes | Key results | Study Weaknesses |
|---|---|---|---|---|---|
| Sensitivity and specificity of a rapid whole blood assay for D-dimer in the diagnosis of pulmonary embolism. Ginsberg JS, Wells PS, Kearon C et al. 1998, Canada | 1250 consecutive referred patients to teaching hospital thromboembolic clinic with putative diagnosis of PE (73 lost to follow up) | Cohort | Diagnostic utility of a combination of low clinical probability of PE on clinical assessment with -ve SimpliRED d-dimer | Negative predictive value of 99% | Exclusion criteria 'lost' 484 of original 1881 patients screened then further 147 excluded due to non consent |
| Derivation of a simple clinical model to categorize patients probability of pulmonary embolism: Increasing the models utility with the SimpliRED d-dimer. Wells PS, Anderson DR, Rodger M et al. 2000, Canada | 1211 patients with presumptive diagnosis of PE broken into derivation and validation set | Diagnostic test | Sensitivity of clinical decision rule with addition of SimpliRED latex agglutination test in diagnosis of PE | 87.8%-88.3% (validation-derivation) | Actual methodology not fully demonstrated e.g. gold standard definition predictive values and likelihood ratios not given |
| A negative SimpliRED d-dimer assay result does not exclude the diagnosis of deep venous thrombosis or pulmonary embolus in emergency department patients. Farrell S, Hayes T, Shaw M. 2000, USA | 198 patients presenting to US ED with suspected thromboembolic disease | Diagnostic test | Diagnostic utility of a combination of low clinical probability of PE on clinical assessment with -ve SimpliRED d-dimer | Negative predictive value 97%<br><br>Sensitivity 84% | Estimation of clinical probability was with implicit not explicit methods 12% patients 'lost' in study |
| Diagnostic accuracy of triage tests to exclude pulmonary embolism. Mac Gillavry MR, Lijmer JG, Sanson BJ et al. 2001, Netherlands | 404 adults, both in and out-patients in teaching hospitals with putative diagnosis of thromboembolic disease | Diagnostic test | Sensitivity and specificity of using a clinical probability and SimpliRED d-dimer test | Sensitivity 98%<br><br>Specificity 11% | Over 50% exclusion rate for entry into study. Implicit methods only for determining clinical probability |
| Excluding pulmonary embolism at the bedside without diagnostic imaging: Management of patients with suspected pulmonary embolism presenting to the emergency department by using a simple clinical model Wells PS, Anderson D, Rodger M et al. 2001, Canada | 946 adult patients referred for assessement of ? PE | Cohort | Diagnostic utility of a combination of low clinical probability of PE on clinical assessment with -ve SimpliRED d-dimer | Negative predictive value 99.5% | Investigation protocol violations occurred in nearly 10% of the patients |
Author Commentary:
Use of a bedside clinical decision rule for PE probability with the additional use of latex agglutination d-dimer testing results in high levels of sensitivity and high negative predictive values in the low PE risk groups. It is this group of patients that makes up the bulk of most patients with a putative diagnosis of PE. However latex agglutination d-dimers do not perform well in high or even moderate risk groups.
Bottom Line:
Patients at low clinical risk with a negative bedside d-dimer can have pulmonary embolus ruled out.
References:
- Ginsberg JS, Wells PS, Kearon C et al.. Sensitivity and specificity of a rapid whole blood assay for D-dimer in the diagnosis of pulmonary embolism.
- Wells PS, Anderson DR, Rodger M et al.. Derivation of a simple clinical model to categorize patients probability of pulmonary embolism: Increasing the models utility with the SimpliRED d-dimer.
- Farrell S, Hayes T, Shaw M.. A negative SimpliRED d-dimer assay result does not exclude the diagnosis of deep venous thrombosis or pulmonary embolus in emergency department patients.
- Mac Gillavry MR, Lijmer JG, Sanson BJ et al.. Diagnostic accuracy of triage tests to exclude pulmonary embolism.
- Wells PS, Anderson D, Rodger M et al.. Excluding pulmonary embolism at the bedside without diagnostic imaging: Management of patients with suspected pulmonary embolism presenting to the emergency department by using a simple clinical model