The LONFLIT4-Concorde Deep Venous Thrombosis and Edema Study: Prevention with Travel Stockings:

Background: The LONFLIT1+2 studies have established that in high risk subjects after long flights (> 10 hours) the incidence of deep venous thrombosis (DVT) is between 4% and 6%. The LONFLIT4 study was designed to evaluate the control of edema and DVT in low-medium risk subjects. The aim of this study was to evaluate edema and its control with specific stockings (ankle pressure between 20 and 30 mm Hg) in long-haul flights. The first part of the study included flights lasting 7-8 hours and the second part included flights lasting 11-12 hours. Ultrasound scans were used to assess thrombosis before and after the flights and a composite edema score was used to evaluate edema and swelling. A group of patients with microan giopathy associated to edema (diabetes, venous hypertension, anti-hypertensive treatment) were also included to evaluate the preventive effects of stockings during flight.Part I: DVT evaluation: Of the 74 subjects in the stocking group and 76 in the control group (150), 144 completed the stu...