Outcomes for inpatients with normal findings on whole-leg ultrasonography: a prospective study.
BACKGROUND
Ultrasonography is used routinely for ruling out suspected deep vein thrombosis in hospitalized patients, although most evidence supporting this strategy is derived from the outpatient setting. This study aimed to estimate the rate of venous thromboembolism when anticoagulant therapy was withheld from inpatients with normal findings on whole-leg ultrasonography.


METHODS
As part of a prospective multicenter cohort study, 1926 medical and surgical inpatients with clinically suspected deep vein thrombosis during their stay were enrolled. Ultrasonography of all lower extremities was performed by board-certified vascular medicine physicians using a standardized examination protocol. Deep vein thrombosis was detected in 395 patients (20%). Anticoagulant therapy was withheld from patients with normal findings, and 523 of them were randomly selected for follow-up. The main outcome measure was 3-month incidence of symptomatic venous thromboembolism.


RESULTS
A total of 513 patients with normal findings on ultrasonography successfully completed 3 months of follow-up, 9 patients were lost to follow-up, and 1 patient received anticoagulant therapy during follow-up. Three patients (0.6%) experienced nonfatal symptomatic venous thromboembolic events confirmed by objective testing. The cause of death was judged to be possibly related to pulmonary embolism for 7 other patients (1.3%). Overall, the 3-month rate of venous thromboembolism was 1.9% (10/513; 95% confidence interval, 0.9-3.5).


CONCLUSIONS
Although withholding anticoagulant therapy after a single negative whole-leg ultrasonography seems to be safe, up to 3.5% of inpatients may nevertheless develop venous thromboembolism in the next 3 months. Further study is warranted to determine whether this strategy is equivalent to serial compression ultrasonography limited to proximal veins.
Sevestre
Marie-Antoinette
MA
Techniques de l'Ingénierie Médicale et de la Complexité, Unité Mixte de Recherche 5525, Centre National de la Recherche Scientifique, Université Joseph Fourier, Grenoble, France; Vascular Medicine Unit, Amiens University Hospital, Amiens, France.
Labarère
José
J
Casez
Pierre
P
Bressollette
Luc
L
Haddouche
Myriam
M
Pernod
Gilles
G
Quéré
Isabelle
I
Bosson
Jean-Luc
JL
D000368:Aged; D000925:Anticoagulants / Q000008:administration & dosage*; D015331:Cohort Studies; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D015994:Incidence; D007866:Leg / Q000098:blood supply* / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome; D014463:Ultrasonography; D020246:Venous Thrombosis / Q000000981:diagnostic imaging* / Q000453:epidemiology* / Q000517:prevention & control
D000925:Anticoagulants