Department of Kinesiology, University of Waterloo, Waterloo, ON, Canada.
Schlegel-University of Waterloo Research Institute for Aging, 250 Laurelwood Dr., Waterloo, ON, N2J 0E2, Canada.
Eur J Appl Physiol. 2021 Mar;121(3):839-848. doi: 10.1007/s00421-020-04547-7. Epub 2021 Jan 2.
Orthostatic hypotension, leading to cerebral hypoperfusion, can result in postural instability and falls in older adults. We determined the efficacy of a novel, intermittent pneumatic compression system, applying pressure around the lower legs, as a countermeasure against orthostatic stress in older adults.
Data were collected from 13 adults (4 male) over 65 years of age. Non-invasive ultrasound measured middle cerebral artery blood velocity (MCAv) and finger photoplethysmography measured mean arterial blood pressure (MAP). Intermittent lower leg compression was applied in a peristaltic manner in the local diastolic phase of each cardiac cycle to optimize venous return during 1-min of seated rest and during a sit-to-stand transition to 1-min of quiet standing with compression initiated 15 s before transition.
During seated rest, compression resulted in a 4.5 ± 6.5 mmHg increase in MAP, and 2.3 ± 2.1 cm/s increase in MCAv (p < 0.05). MAP and MCAv increased during the 15 s of applied compression before the posture transition (2.3 ± 7.2 mmHg and 2.1 ± 4.0 cm/s, respectively, p < 0.05) with main effects for both variables confirming continued benefit during the transition and quiet stand periods.
Application of carefully timed, intermittent compression to the lower legs of older adults increased MAP and MCAv during seated rest and maintained an elevated MAP and MCAv during a transition to standing posture. Future research could assess the benefits of this technology for persons at risk for orthostatic hypotension on standing and while walking in an effort to reduce injurious, unexplained falls in older adults.
体位性低血压导致脑灌注不足,可导致老年人姿势不稳和跌倒。我们确定了一种新型间歇性气动压缩系统的疗效,该系统在下腿周围施加压力,作为对抗老年人体位性应激的对策。
从 13 名 65 岁以上的成年人(4 名男性)中收集数据。非侵入性超声测量大脑中动脉血流速度(MCAv),手指光容积描记法测量平均动脉血压(MAP)。间歇性小腿压缩以蠕动方式施加,在每个心动周期的局部舒张期内,在 1 分钟的坐姿休息期间和在从坐姿到站立的过渡期间,在 1 分钟的安静站立期间优化静脉回流,在过渡前 15 秒开始压缩。
在坐姿休息期间,压缩导致 MAP 增加 4.5±6.5mmHg,MCAv 增加 2.3±2.1cm/s(p<0.05)。在体位过渡前的 15 秒应用压缩期间,MAP 和 MCAv 增加(分别为 2.3±7.2mmHg 和 2.1±4.0cm/s,p<0.05),两个变量的主要效应均证实过渡和安静站立期间持续受益。
将精心定时的间歇性压缩应用于老年人的小腿可在坐姿休息期间增加 MAP 和 MCAv,并在过渡到站立姿势期间维持升高的 MAP 和 MCAv。未来的研究可以评估这种技术对直立和行走时体位性低血压风险者的益处,以减少老年人不明原因的跌倒受伤。