Data from: A cohort feasibility study of an intermittent pneumatic compression device within a below-knee cast for the prevention of venous thromboembolism

Objectives: To determine the likely enrolment rate of eligible participants into a randomised controlled trial (RCT) in which a within-cast intermittent pneumatic compression device using Jet Impulse Technology (IPC/JIT) is one of three possible interventions in a RCT for prevention of venous thromboembolism (VTE) in the clinical setting of isolated lower limb cast immobilisation.
Design: A prospective, open-label feasibility study of the IPC/JIT device placed within a lower limb cast.
Setting: Wellington Regional Hospital Fracture Clinic
Participants: Individuals aged 18 to 70 who presented with a lower limb injury requiring a minimum of four weeks below-knee cast immobilisation.
Intervention: Placement of an IPC/JIT device within lower limb cast.
Outcome measures: The main outcome measure was the proportion of eligible participants who participated in the feasibility study. Secondary outcome measures included adherence to device utilisation throughout the study, ease of application of the device and adverse events potentially associated with its use.
Results: The proportion of potentially eligible participants for the IPC/JIT device was only 7/142 (5%), 95% CI 2 to 9.9. Devices were used for a mean (range) of 4.1 (1.9 to 10.2) hours per day and none of seven participants had adequate adherence to the device. Three of the seven participants suffered an adverse event, including one DVT, one dorsal foot ulcer and one skin maceration.
Conclusions: A within-cast IPC/JIT device is unlikely to be a feasible randomisation arm for a RCT assessing possible interventions for the reduction of VTE risk in the clinical setting of lower limb injury requiring below knee cast immobilisation for a minimum of four weeks.
Trial registration: This trial was prospectively registered (ANZCTR 12615000192583 and was approved by the New Zealand Health and Disability Ethics Committees (14/STH/138/AM03).

研究目的：旨在明确一项针对单纯下肢石膏固定临床场景下静脉血栓栓塞症（Venous Thromboembolism, VTE）预防的随机对照试验（Randomised Controlled Trial, RCT）中，符合入组条件的受试者的潜在入组比例。该试验共设置三种干预措施，其中一种为采用脉冲喷射技术（Jet Impulse Technology, JIT）的石膏内置式间歇充气加压装置（Intermittent Pneumatic Compression, IPC/JIT）。
研究设计：一项针对置于下肢石膏内的IPC/JIT装置的前瞻性、开放标签可行性研究。
研究地点：惠灵顿区域医院骨折门诊
研究对象：年龄18至70岁，因下肢损伤需接受至少4周膝下石膏固定的个体。
干预措施：在下肢石膏内置入IPC/JIT装置。
结局指标：主要结局指标为符合入组条件的受试者参与本可行性研究的比例。次要结局指标包括：研究全程中受试者对装置使用的依从性、装置佩戴操作的便捷性，以及可能与装置使用相关的不良事件。
研究结果：符合IPC/JIT装置入组条件的潜在受试者占比仅为7/142（5%），95%置信区间为2%~9.9%。受试者每日使用装置的平均时长（范围）为4.1（1.9~10.2）小时，7名受试者均未达到足够的装置使用依从性。7名受试者中共有3例不良事件，包括1例深静脉血栓形成（Deep Vein Thrombosis, DVT）、1例足背溃疡及1例皮肤浸渍。
研究结论：对于需接受至少4周膝下石膏固定的下肢损伤患者，在评估降低VTE风险干预措施的RCT中，石膏内置式IPC/JIT装置不太可能成为可行的随机分组干预方案。
试验注册：本试验已前瞻性注册（ANZCTR 12615000192583），并获得新西兰卫生与残疾伦理委员会批准（14/STH/138/AM03）。