Callender Nigel A, Øivind Høiseth Lars, Mathiesen Iacob, Hisdal Jonny
Faculty of Medicine, University of Oslo, Norway.
Department of Vascular Surgery, Oslo University Hospital, Norway.
Vasa. 2025 Mar;54(2):113-123. doi: 10.1024/0301-1526/a001172. Epub 2025 Jan 9.
Intermittent negative pressure is an emerging treatment for lower limb vascular disease but the specific physiological effects, particularly upon large artery haemodynamics are unclear. This study examined the influence of intermittent negative pressure upon popliteal artery shear rate during both supine and sitting postures. Eleven healthy participants (5 female; age: 28.3 ± 5.8 y; weight: 69.6 ± 9.8 kg, height: 1.75 ± 0.07 m) received intermittent negative pressure (-37 mmHg; 9.5-sec on, 7.5-sec off), upon the lower leg during both supine and sitting postures. Popliteal artery blood flow and shear rate were recorded (duplex ultrasound), accompanied by heart rate (3-lead ECG) and blood pressure (volume clamp method). Compared to sitting, a supine posture led to greater mean shear rate during baseline (supine: 21[9]; sitting: 17[13] sec; all median [IQR]) and negative pressure phases (supine: 24[15]; sitting: 17[14] sec; both p<0.05). While supine, negative pressure raised mean shear rate above baseline levels (p<0.05) and reduced it upon return to atmospheric pressure (p < 0.05). In sitting, mean shear rate only differed from baseline at the points of peak and minimum shear (peak:18[17]; minimum: 10[9] sec; both p<0.05). Shear pattern (oscillatory shear index) showed changes from baseline during both postures (p<0.05), but was not different between postures. Conclusions: Intermittent negative pressure influenced lower limb popliteal artery shear rate during both the supine and sitting postures, the effect was greater while supine. Fluctuation in shear pattern seen during both positions may account for positive clinical effects observed following intermittent negative pressure treatment. These findings are framed against previous work investigating clinical populations. Future work should investigate any differences in lower limb haemodynamics and markers of endothelial function among patients with vascular disease.
间歇性负压是一种新兴的下肢血管疾病治疗方法，但具体的生理效应，尤其是对大动脉血流动力学的影响尚不清楚。本研究考察了仰卧位和坐位时间歇性负压对腘动脉剪切速率的影响。11名健康参与者（5名女性；年龄：28.3±5.8岁；体重：69.6±9.8千克，身高：1.75±0.07米）在仰卧位和坐位时小腿均接受间歇性负压（-37毫米汞柱；开启9.5秒，关闭7.5秒）。记录腘动脉血流和剪切速率（双功超声），同时记录心率（三导联心电图）和血压（容积钳法）。与坐位相比，仰卧位在基线期（仰卧位：21[9]；坐位：17[13]秒；均为中位数[四分位间距]）和负压期（仰卧位：24[15]；坐位：17[14]秒；均p<0.05）导致更高的平均剪切速率。仰卧位时，负压使平均剪切速率升高至基线水平以上（p<0.05），恢复至大气压时降低（p<0.05）。在坐位时，平均剪切速率仅在剪切峰值和最小值点与基线不同（峰值：18[17]；最小值：10[9]秒；均p<0.05）。剪切模式（振荡剪切指数）在两种体位时均显示与基线有变化（p<0.05），但体位间无差异。结论：间歇性负压在仰卧位和坐位时均影响下肢腘动脉剪切速率，仰卧位时影响更大。两种体位时观察到的剪切模式波动可能解释了间歇性负压治疗后观察到的积极临床效果。这些发现是基于之前对临床人群的研究得出的。未来的工作应研究血管疾病患者下肢血流动力学和内皮功能标志物的差异。
