A highly sensitive ELISA D-dimer increases testing but not diagnosis of pulmonary embolism.
OBJECTIVE
To determine the effect of introducing a rapid enzyme-linked immunosorbent assay (ELISA) D-dimer on the percentage of emergency department (ED) patients evaluated for pulmonary embolism (PE), the use of associated laboratory testing, pulmonary vascular imaging, and the diagnoses of PE.


METHODS
Patients evaluated for PE during three 120-day periods were enrolled: immediately before (period 1), immediately after (period 2), and one year after the introduction of a rapid ELISA D-dimer in the hospital. The frequency of ED patients evaluated for PE with any test, with D-dimer testing, and with pulmonary vascular imaging and the frequency of PE diagnosis during each time period were determined.


RESULTS
The percentage of patients evaluated for PE nearly doubled; from 1.36% (328/24,101) in period 1 to 2.58% (654/25,318) in period 2 and 2.42% (583/24,093) in period 3. The percentage of patients who underwent D-dimer testing increased more than fourfold; from 0.39% (93/24,101) in period 1 to 1.83% (464/25,318) in period 2 and 1.77% (427/24,093) in period 3. The percentage of patients who underwent pulmonary vascular imaging increased from 1.02% (247/24,101) in period 1 to 1.36% (344/25,318) in period 2 and to 1.39% (334/24,093) in period 3. There was no difference in the percentage of patients diagnosed as having PE in period 1 (0.20% [47/24,101]), period 2 (0.27% [69/25,318]), and period 3 (0.24% [58/24,093]).


CONCLUSIONS
In the study's academic ED, introduction of ELISA D-dimer testing was accompanied by an increase in PE evaluations, D-dimer testing, and pulmonary vascular imaging; there was no observed change in the rate of PE diagnosis.
Kabrhel
Christopher
C
Department of Emergency Medicine, Massachusetts General Hospital, Boston, MA 02114, USA. ckabrhel@partners.org
Matts
Christina
C
McNamara
Mariah
M
Katz
Jeremy
J
Ptak
Thomas
T
D004636:Emergency Service, Hospital / Q000706:statistics & numerical data*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005338:Fibrin Fibrinogen Degradation Products / Q000032:analysis*; D006801:Humans; D008297:Male; D008404:Massachusetts; D008875:Middle Aged; D010043:Outcome and Process Assessment, Health Care; D011655:Pulmonary Embolism / Q000097:blood / Q000175:diagnosis*; D012680:Sensitivity and Specificity
D005338:Fibrin Fibrinogen Degradation Products; C036309:fibrin fragment D