Venous haemodynamics of Jet Impulse Technology within a lower limb fibreglass cast: a randomized controlled trial

• Published in: JRSM open Vol. 8; no. 2; p. 2054270416681746
• Main Authors: Braithwaite, Irene, Mackintosh, Stephen, Buchanan, Samantha, Schwarzenlander, Kerstin, De Ruyter, Bernadette
• Format: Journal Article
• Language: English
• Published: London, England SAGE Publications 01.02.2017; Sage Publications Ltd
• Subjects: Clinical trials; Flow velocity; Hemodynamics; Knee; Thromboembolism; below-knee cast; lower limb immobilisation; venous stasis; Jet Impulse Technology; venous thromboembolism; venous haemodynamics; prevention
• ISSN: 2054-2704; 2054-2704
• DOI: 10.1177/2054270416681746

Objectives We investigated popliteal venous haemodynamics of the VenaJet Jet Impulse Technology system within a below-knee fibreglass cast. Design Randomized controlled trial. Participants Twenty-four healthy participants aged 18–54 had both feet placed within the Jet Impulse Technology system and were randomised for one or other leg to be within a below-knee fibreglass cast. Setting Pacific Radiology, Lower Hutt, Wellington Main outcome measures The primary outcome variable was peak systolic velocity (cm/s) compared between legs with and without the cast at 60 min (after 10 min Jet Impulse Technology activation), using a mixed linear model and a non-inferiority bound of 4.8 cm/s. Secondary outcome variables were the difference in peak systolic velocity between the casted limb and the non-casted limb at baseline and 40 min after casting, and the difference in mean flow velocity (cm/s), vein diameter (mm), and total volume flow (L/min) between the casted limb and the non-casted limb at baseline, 40 and 60 min. Results The mean (standard deviation) peak systolic velocity was 4.6(1.5), 4.8(1.1), 28.8(16.1), and 4.3(1.2), 4.8(1.4) and 29.3(19.0) cm/s at baseline, 40 and 60 min in the casted and non-casted leg, respectively. The difference (95% confidence interval) between cast and no-cast at 60 min was −0.8 (−6.5 to 4.9) cm/s, P = 0.78. The peak systolic velocity, flow velocity and total volume flow at 40 min were not statistically significantly different from baseline for both casted and non-casted limb. Conclusion In healthy volunteers, the popliteal venous haemodynamics of the Jet Impulse Technology system was similar between the legs with and without a below-knee fibreglass cast. In-cast Jet Impulse Technology may provide a non-pharmacological option for venous thromboembolism prophylaxis for lower-limb cast-immobility.