Abu-Own A, Sommerville K, Scurr J H, Coleridge Smith P D
Department of Surgery, University College London Medical School, Middlesex Hospital, U.K.
Eur J Vasc Endovasc Surg. 1995 Apr;9(3):327-34. doi: 10.1016/s1078-5884(05)80139-x.
To assess the effects of compression on the skin microcirculation of the heel using laser Doppler fluxmetry.
Parallel groups comparing patients with control groups.
Department of Surgery, University College London Medical School, London.
Ten patients at risk of developing pressure ulceration, 10 age- and sex-matched healthy subjects and 10 young, healthy volunteers. An acrylic indenter with a slot to accommodate a laser Doppler probe was used to apply compression to the heel region. A pressure sensor was used to measure the applied compression.
The resting laser Doppler flux was measured with the subject lying supine. Compression forces were then applied in increments from 50 g to 1500 g and the corresponding interface pressure (IP) and laser Doppler flux (LDF) recorded. The IP and LDF were also measured from the heel while the subject was lying on a low air-loss system and then on an NHS conventional hospital bed.
The resting LDF is lower in the patient group compared to the control groups (p < 0.05). Compression of the heel caused a progressive decrease in LDF in all groups. Compression greater than 50 mmHg as well as lying on an NHS bed reduced the LDF signal to a minimal value (biological zero). On the low air-loss system, the median LDF was 17% of the resting value in the age-matched control group and 32% in the patient group.
The results indicate that the heel microcirculation is vulnerable to compression. The low air-loss system maintained the IP sufficiently low to prevent complete cessation of the heel microcirculation.
使用激光多普勒血流仪评估压迫对足跟皮肤微循环的影响。
平行组比较患者与对照组。
伦敦大学学院医学院外科。
10名有发生压疮风险的患者、10名年龄和性别匹配的健康受试者以及10名年轻健康志愿者。使用带有狭槽以容纳激光多普勒探头的丙烯酸压头对足跟区域施加压迫。使用压力传感器测量施加的压迫力。
受试者仰卧时测量静息激光多普勒血流。然后以50克至1500克的增量施加压迫力，并记录相应的界面压力（IP）和激光多普勒血流（LDF）。当受试者躺在低气耗系统上然后躺在国民保健服务（NHS）常规医院床上时，也从足跟测量IP和LDF。
与对照组相比，患者组的静息LDF较低（p<0.05）。足跟压迫导致所有组的LDF逐渐降低。大于50 mmHg的压迫以及躺在NHS床上会使LDF信号降至最小值（生物学零值）。在低气耗系统上，年龄匹配对照组的中位LDF为静息值的17%，患者组为32%。
结果表明足跟微循环易受压迫影响。低气耗系统将IP维持在足够低的水平，以防止足跟微循环完全停止。
