Superficial venous thrombosis (SVT) can progress to deep venous thrombosis (DVT) and pulmonary embolism. Patient and thrombus characteristics are related to this. This study aims to identify 1. Use of venous duplex ultrasound (VDU) in SVT, 2. Whether VDU protocols and reports inform care pathways, 3. Is there a care gap?
A literature review, survey for critical findings (CF) and an audit of VDU reports were assayed with respect to SVT. Surveys were performed of ultrasound facilities, specialists and family practitioners to identify approaches to SVT and identify care gaps.
The literature shows a significant risk of SVT extension (7 – 48%). High-risk clinical situations include malignancy, coagulation abnormality, varicose veins, previous SVT or DVT and multiple risk factors. High-risk ultrasound characteristics include proximity to a junction ( < 2-5cm), length (>5cm) and bilateral or multiple areas of involvement. The interpretation report audit (n=20) showed location of SVT (100%), proximity to junctions (50%), bilateral findings (50%), multiple areas (25%) and length > 5cm (20%). The CF survey (n=81) showed that facilities considered SVT as a CF (17% all – 50% selected); proximity 61%, length 12% and multiple or bilateral 20% were cited in protocols and reports. Preliminary results of clinicians’ survey (n=46) showed 56% would order a VDU; 80% want information on thrombus characteristics but see these details in reports in only 36%. The surveys of facilities and clinicians are ongoing.
SVT is significant; there are recognized risk factors for progression. Approaches to patient care do not fully recognize this. VDU protocols and reports do not give adequate information to inform clinical care. Significant gaps exist with respect to VDU assessments, identification of risk and clinical management of SVT. Advocacy and education are suggested to address this gap.
Douglas Wooster, Professor of Surgery, University of Toronto