Comparison of Different Intermittent Pneumatic Compression Devices for Deep Vein Thrombosis

Study Overview
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Brief Summary
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Various kinds of intermittent pneumatic compression devices (IPC) with particular ways of compression have been developed and used for prevention of deep vein thrombosis. There are still some controversies about the physiologic properties and clinical impact of numerous issues including the variety of the cuff length, inflation rate, compression sequence, compression-relaxation cycle rate, and pressure generation characteristics. This study is designed to compare clinical efficacies as well as venous hemodynamic improvements between Simultaneous bilateral compression with fixed venous refill time versus alternate compression with adjusted refill time

Official Title
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The Influence of the Different Ways of Pneumatic Compression on Clinical and Physiologic Efficacies in Preventing Deep Vein Thrombosis: a Randomised Comparative Study

Conditions
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Venous Thrombosis, Deep Vein Thrombosis

Intervention / Treatment
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* Device: DVT-3000
* Device: SCD Express


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: the patients who undergo total knee replacement arthroplasty Exclusion Criteria: (1) chronic superficial or deep venous insufficiency, (2) venous anomalies like duplication of the superficial femoral vein, (3) previous venous thromboembolism history, (4) being under anticoagulation therapy, (5) severe arteriosclerosis obliterans without palpable dorsalis pedis pulse, (6) open fracture, hemorrhagic condition, or extensive dermatitis at lower legs, (7) congestive heart failure. Additional exclusion criteria included a documented malignant tumor, because pharmacologic prophylaxis with anticoagulants would be more reasonable in this case.
Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Simultaneous compression+Fixed refill time<br>Simultaneous bilateral compression with fixed venous refill time through the whole duration of pneumatic compression | Device: DVT-3000<br> <br> * Other names: Fixed venous refill time;|
| Active Comparator: Alternate compression+Adjusted refill time<br>alternate bilateral compression with adjusted venous refill time which would change several times during pneumatic compression | Device: SCD Express<br> <br> * Other names: Adjusted venous refill time;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Rate of Deep Vein Thrombosis | Computed tomographic angiography were performed on 4th postoperative days to detect deep vein thrombosis and evaluate its extent and location. | On 4th postoperative days after total knee replacement arthroplasty | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Peak Velocity | Doppler ultrasonography were performed to measure one of the venous hemodynamic parameters to be compared. A longitudinal scans of bilateral superficial femoral veins, just distal to the confluence of the profunda femoral veins, were performed. Baseline velocity, flow pattern, and augmented flow of 11 seconds (Simultaneous compression arm) or 12 seconds (Alternate compression arm) were recorded. Under fixed state of other ultrasound scan parameters, peak velocity (PV) was measured by determination of maximum point of the augmented waveform. | On 4th postoperative days after total knee replacement arthroplasty | 
| Mean Velocity | Doppler ultrasonography were performed to measure one of the venous hemodynamic parameters to be compared. A longitudinal scans of bilateral superficial femoral veins, just distal to the confluence of the profunda femoral veins, were performed. Baseline velocity, flow pattern, and augmented flow of 11 seconds (Alternate compression arm) or 12 seconds (Simultaneous compression arm) were recorded. This is an automatically measured mean value of venous flow. | On 4th postoperative days after total knee replacement arthroplasty | 
| Peak Volume Flow | Doppler ultrasonography were performed to measure one of the venous hemodynamic parameters to be compared. A longitudinal scans of bilateral superficial femoral veins, just distal to the confluence of the profunda femoral veins, were performed. Baseline velocity, flow pattern, and augmented flow of 11 seconds (Simultaneous compression arm) or 12 seconds (Alternate compression arm) were recorded. Peak volume flow (PVF) was automatically calculated with 1-second interval around the PV. | On 4th postoperative days after total knee replacement arthroplasty | 
| Total Volume Flow | Doppler ultrasonography were performed to measure one of the venous hemodynamic parameters to be compared. A longitudinal scans of bilateral superficial femoral veins, just distal to the confluence of the profunda femoral veins, were performed. Baseline velocity, flow pattern, and augmented flow of 11 seconds (Simultaneous compression arm) or 12 seconds (Alternate compression arm) were recorded. Total volume flow (TVF) was automatically calculated by the software. | On 4th postoperative days after total knee replacement arthroplasty | 
| Expelled Total Volume | Expelled volume was theoretically calculated value in order to figure out how much blood was squeezed by the compression for an hour; expelled total volume (ETV) = single cycle augmented TVF x cycling rate (cycles/hour). | On 4th postoperative days after total knee replacement arthroplasty | 
| Expelled Peak Volume | Expelled volume was theoretically calculated value in order to figure out how much blood was squeezed by the compression for an hour; expelled peak volume (EPV) = single cycle augmented PVF x cycling rate (cycles/hour). | On 4th postoperative days after total knee replacement arthroplasty | 
| Augmented PV | Enhanced peak velocity by application of intermittent pneumatic compression | On 4th postoperative days after total knee replacement arthroplasty | 
| Augmented MV | Enhanced mean velocity by application of pneumatic compression | On 4th postoperative days after total knee replacement arthroplasty | 
| Augmented PVF | Enhanced peak volume flow by application of pneumatic compression | On 4th postoperative days after total knee replacement arthroplasty | 
| Augmented TVF | Enhanced total volume flow by application of pneumatic compression | on 4th postoperative day after total knee replacement arthroplasty | 
| Cycling Rate | Number of cuff inflation-deflation cycle during an hour. In group SF, the cycling rate is fixed as 90 cycles/hour, but in group AA, it is variable according to the individual venous refill time. | on 4th postoperative day after total knee replacement arthroplasty | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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deep vein thrombosis, intermittent pneumatic compression, venous hemodynamics