压疮易患组织的激光多普勒血流信号小波分析

Wavelet analysis of laser Doppler perfusion signal in risk area for pressure ulcer

应用激光多普勒血流仪(LDF)实时监测了脊椎损伤病人压疮易患组织在静息条件下及局部血流压力阻断后的微循环血流状况,并应用小波变换分析了血流信号的脉动性。研究发现,与健康人员相比,脊椎损伤病人在静息条件下,血流信号中与内皮相关的代谢性活动脉动幅度显著性降低(F=5.26,p=0.032);在局部血流压力阻断后的脉动响应中,神经性活动脉动响应幅度显著性降低(F=5.44,p=0.029)。结果表明,脊椎损伤病人血流信号中与内皮相关的代谢活动及神经性活动,对于血流调整具有相对较小的贡献。

The blood oscillations in the skin over the ischial tuberosity are assessed using the spectral analysis of laser Doppler flowmetry （LDF） signals based on wavelet transform. A total of ten male sub jects were recruited for this study,of which five were normal subjects （age=31.2±3.3 year） and the other five were persons with spinal cord injury （age=37.2 ±7.3 year）. External pressure of 16.0kPa （120 mmHg） was applied to the ischial tuberosity via one specifically designed pneumatic indentor. The loading duration was 30 minutes. The results show that the normalized amplitude of the metabolic component for persons with SCI is significantly lower （F=5.26 ,p=0. 032） during the resting conditions as compared with normal individuals. And the normalized amplitude of the neurogenic component （0.02-0. 06 Hz） during post loading is significantly lower for persons with SCI （F=5.44,p=0. 029）. These re suits suggest that the contributions of endothelial related metabolic and neurogenic activities to the blood perfusion regulation become relatively less for persons with SCI during the resting and post loading periods respectively.