Scurr J H, Machin S J, Bailey-King S, Mackie I J, McDonald S, Smith P D
Department of Surgery, Royal Free and University College Medical School, London, UK.
Lancet. 2001 May 12;357(9267):1485-9. doi: 10.1016/S0140-6736(00)04645-6.
The true frequency of deep-vein thrombosis (DVT) during long-haul air travel is unknown. We sought to determine the frequency of DVT in the lower limb during long-haul economy-class air travel and the efficacy of graduated elastic compression stockings in its prevention.
We recruited 89 male and 142 female passengers over 50 years of age with no history of thromboembolic problems. Passengers were randomly allocated to one of two groups: one group wore class-I below-knee graduated elastic compression stockings, the other group did not. All the passengers made journeys lasting more than 8 h per flight (median total duration 24 h), returning to the UK within 6 weeks. Duplex ultrasonography was used to assess the deep veins before and after travel. Blood samples were analysed for two specific common gene mutations, factor V Leiden (FVL) and prothrombin G20210A (PGM), which predispose to venous thromboembolism. Asensitive D-dimer assay was used to screen for the development of recent thrombosis.
12/116 passengers (10%; 95% CI 4.8-16.0%) developed symptomless DVT in the calf (five men, seven women). None of these passengers wore elastic compression stockings, and two were heterozygous for FVL. Four further patients who wore elastic compression stockings, had varicose veins and developed superficial thrombophlebitis. One of these passengers was heterozygous for both FVL and PGM. None of the passengers who wore class-I compression stockings developed DVT (95% CI 0-3.2%).
We conclude that symptomless DVT might occur in up to 10% of long-haul airline travellers. Wearing of elastic compression stockings during long-haul air travel is associated with a reduction in symptomless DVT.
长途航空旅行期间深静脉血栓形成（DVT）的实际发生率尚不清楚。我们试图确定长途经济舱航空旅行期间下肢DVT的发生率以及分级弹性加压袜预防DVT的效果。
我们招募了89名男性和142名50岁以上且无血栓栓塞问题病史的女性乘客。乘客被随机分配到两组中的一组：一组穿着I级膝下分级弹性加压袜，另一组不穿。所有乘客每次飞行的旅程持续超过8小时（中位总时长24小时），并在6周内返回英国。使用双功超声检查旅行前后的深静脉。对血样进行两种特定常见基因突变的分析，即因子V莱顿（FVL）和凝血酶原G20210A（PGM），这两种基因突变易导致静脉血栓栓塞。使用敏感的D - 二聚体检测来筛查近期血栓形成的发生情况。
12/116名乘客（10%；95%可信区间4.8 - 16.0%）在小腿出现无症状DVT（5名男性，7名女性）。这些乘客中没有人穿着弹性加压袜，2人是FVL杂合子。另外4名穿着弹性加压袜、患有静脉曲张并发生浅静脉血栓形成的患者。其中1名乘客FVL和PGM均为杂合子。穿着I级加压袜的乘客中无人发生DVT（95%可信区间0 - 3.2%）。
我们得出结论，多达10%的长途航空旅行者可能会发生无症状DVT。长途航空旅行期间穿着弹性加压袜与无症状DVT的减少有关。
