title: Application of a diagnostic clinical model for the management of hospitalized patients with suspected deep-vein thrombosis.
abstract: The purpose of this study was to evaluate whether the determination of pretest probability using a simple clinical model and the SimpliRED D-dimer could be used to improve the management of hospitalized patients with suspected deep-vein thrombosis. Consecutive hospitalized patients with suspected deep-vein thrombosis, had their pretest probability determined using a clinical model and had a SimpliRED D-dimer assay. Patients at low pretest probability underwent a single ultrasound test. A negative ultrasound excluded the diagnosis of deep-vein thrombosis whereas a positive ultrasound was confirmed by venography. Patients at moderate pretest probability with a positive ultrasound were treated for deep-vein thrombosis whereas patients with an initial negative ultrasound underwent a single follow-up ultrasound one week later. Patients at high pretest probability with a positive ultrasound were treated whereas those with negative ultrasound underwent venography. All patients were followed for three months for the development of venous thromboembolic complications. Overall, 28% (42/150), and 10% (5/50), 21% (14/71) and 76% (22/29) of the low, moderate and high pretest probability patients. respectively, had deep vein thrombosis. Two of 111 (1.8%; 95% CI = 0.02% to 6.4%) patients considered to have deep vein thrombosis excluded had events during three-month follow-up. Overall 13 of 150 (8.7%) required venography and serial testing was limited to 58 of 150 (38.7%) patients. The negative predictive value of the SimpliRED D-dimer in patients with low pretest probability was 96.2%, which is not statistically different from the negative predictive value of a negative ultrasound result in low pretest probability patients (97.8%). Management of hospitalized patients with suspected deep-vein thrombosis based on clinical probability and ultrasound of the proximal deep veins is safe and feasible.
authors.affiliation: Department of Medicine, University of Ottawa, Ontario, Canada.
authors.forename: P S
authors.initials: PS
authors.lastname: Wells
authors.forename: D R
authors.initials: DR
authors.lastname: Anderson
authors.forename: J
authors.initials: J
authors.lastname: Bormanis
authors.forename: F
authors.initials: F
authors.lastname: Guy
authors.forename: M
authors.initials: M
authors.lastname: Mitchell
authors.forename: L
authors.initials: L
authors.lastname: Gray
authors.forename: C
authors.initials: C
authors.lastname: Clement
authors.forename: K S
authors.initials: KS
authors.lastname: Robinson
authors.forename: B
authors.initials: B
authors.lastname: Lewandowski
mesh_terms: D015331:Cohort Studies; D005260:Female; D005338:Fibrin Fibrinogen Degradation Products; D006760:Hospitalization; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D020246:Venous Thrombosis / Q000175:diagnosis* / Q000628:therapy*
chemical_list: D005338:Fibrin Fibrinogen Degradation Products; C036309:fibrin fragment D