Callender Nigel A, Høiseth Lars Øivind, Hisdal Jonny
Faculty of Medicine, University of Oslo, Oslo, Norway.
Department of Vascular Surgery, Oslo University Hospital, Oslo, Norway.
PLoS One. 2024 Dec 5;19(12):e0315231. doi: 10.1371/journal.pone.0315231. eCollection 2024.
Recently intermittent negative pressure has emerged as a potential treatment in vascular disease and has similarities with established experimental interventions such as lower body negative pressure. The direct, local influences of either method upon intravascular pressure still require some clarification however, particularly in the immediate moments following onset. We investigated the acute intravascular pressure responses to intermittent cycles of negative pressure in the supine and sitting postures. Fifteen participants (6 female) received intermittent negative pressure cycles (-37 mmHg; 9.5-sec on, 7.5-sec off) upon the lower leg in both postures. Saphenous venous (n = 15), and dorsalis pedis artery pressure (n = 3) were recorded via pressure catheter, alongside beat-by-beat systemic cardiovascular parameters (heart rate and blood pressure; n = 15), from which the arteriovenous pressure gradient was ultimately derived. Negative pressure induced a transient reduction in local intravenous pressure (Supine: 14±3 mmHg to -18±6 mmHg, p<0.001; Sitting: 58±10 mmHg to 41±10 mmHg, p<0.001). Rate of venous pressure recovery during the negative pressure plateau phase was faster during sitting, than supine (1.94±0.72 vs. 1.06±0.69 mmHg·sec-1; p = 0.002). Local intraarterial pressure did not change. External negative pressure readily transmits to the superficial intravenous environment of the leg and transiently augments the arteriovenous pressure gradient. The greatest and most sustained effect was during the supine position. The augmented arteriovenous gradient might briefly produce Poiseuille-dependent haemodynamics before local autoregulatory mechanisms engage. These findings benefit understanding of the immediate in-vivo effects of negative pressure upon the local vasculature, and may partly account for the positive clinical effects of intermittent negative pressure treatments in vascular disease.
最近，间歇性负压已成为血管疾病的一种潜在治疗方法，并且与诸如下体负压等已确立的实验性干预措施有相似之处。然而，这两种方法对血管内压力的直接局部影响仍需要进一步阐明，尤其是在开始后的即刻。我们研究了仰卧位和坐位时间歇性负压循环对急性血管内压力的反应。15名参与者（6名女性）在两种体位下小腿均接受间歇性负压循环（-37 mmHg；开启9.5秒，关闭7.5秒）。通过压力导管记录大隐静脉压力（n = 15）和足背动脉压力（n = 3），同时记录逐搏的全身心血管参数（心率和血压；n = 15），最终由此得出动静脉压力梯度。负压导致局部静脉压力短暂降低（仰卧位：从14±3 mmHg降至-18±6 mmHg，p<0.001；坐位：从58±10 mmHg降至41±10 mmHg，p<0.001）。在负压平稳期，坐位时静脉压力恢复速度比仰卧位快（1.94±0.72 vs. 1.06±0.69 mmHg·sec-1；p = 0.002）。局部动脉压力未发生变化。外部负压很容易传递到腿部的浅表静脉环境，并短暂增加动静脉压力梯度。最大且最持久的影响发生在仰卧位时。在局部自动调节机制起作用之前，增加的动静脉梯度可能会短暂产生泊肃叶依赖性血流动力学。这些发现有助于理解负压对局部血管系统的即时体内效应，并且可能部分解释了间歇性负压治疗在血管疾病中的积极临床效果。
