Polianskis Romanas, Graven-Nielsen Thomas, Arendt-Nielsen Lars
Laboratory for Experimental Pain Research, Center for Sensory-Motor Interaction, Aalborg University, Frederik Bajers Vej 7, D-3, DK-9220, Aalborg, Denmark.
Pain. 2002 Nov;100(1-2):19-26. doi: 10.1016/s0304-3959(02)00162-8.
This study assessed spatial and temporal aspects of pressure pain during increasing and constant compressions using a cuff algometer and during adaptive compressions using a closed-loop feedback system for maintaining stable pain. Experimental setup consisted of a pneumatic tourniquet cuff, a computer-controlled air compressor, and a 10-cm electronic visual analogue scale (VAS). The first experiment assessed spatial summation for cuff pain by recording the pressure-pain stimulus-response (SR) function during increasing compressions with single and double cuffs. The second experiment assessed temporal profile of cuff pain during constant compression for 10 min beginning at pain intensities of 2, 4, and 6 cm on the VAS. The third experiment assessed temporal pressure profile when pain was maintained for 10 min by a close-loop system within target zones of +/-0.5 cm VAS at pain intensities of 2, 4, and 6 cm on the VAS.Doubling the tissue volume under the cuff shifted the SR function to the left, demonstrating spatial summation. The constant cuff pressure evoked typical biphasic response consisting of an overshoot in pain intensity, followed by decreasing pain, or adaptation. The pain intensity was significantly correlated to the time of constant stimulation, showing time-dependency of pain encoding. Both overshoot magnitude and adaptation rate were dependent on the starting pain intensity. The pain decrease rate was lowest for a pain intensity of 2 cm on the VAS. The overshoot magnitude was lowest for a pain intensity of 6 cm on the VAS. Both the overshoot and the adaptation were maximal for a pain intensity of 4 cm on the VAS. The oscillating pressure generated by closed-loop system led to constant rather than adapting pain at intensities of 2, 4, and 6 cm on the VAS. The cuff algometer is highly configurable tool for assessment of pain sensitivity by pressure-pain and time-pain functions. The presented models are useful additions to a researcher's armamentarium for further pharmacological and clinical studies on deep tissue pain and related mechanisms.
本研究使用袖带式压力痛觉计评估了递增和持续加压过程中压力性疼痛的空间和时间方面，以及使用闭环反馈系统维持稳定疼痛的适应性加压过程中的压力性疼痛。实验装置包括一个气动止血带袖带、一台计算机控制的空气压缩机和一个10厘米的电子视觉模拟评分量表（VAS）。第一个实验通过记录单袖带和双袖带递增加压过程中的压力-疼痛刺激-反应（SR）函数，评估袖带疼痛的空间总和。第二个实验评估了在VAS上疼痛强度为2、4和6厘米时开始持续加压10分钟期间袖带疼痛的时间特征。第三个实验评估了在VAS上疼痛强度为2、4和6厘米时，通过闭环系统在±0.5厘米VAS的目标区域内将疼痛维持10分钟时的时间压力特征。将袖带下的组织体积加倍会使SR函数向左移动，表明存在空间总和。持续的袖带压力引发了典型的双相反应，包括疼痛强度的过冲，随后疼痛减轻或适应。疼痛强度与持续刺激时间显著相关，表明疼痛编码具有时间依赖性。过冲幅度和适应率均取决于起始疼痛强度。VAS上疼痛强度为2厘米时疼痛减轻率最低。VAS上疼痛强度为6厘米时过冲幅度最低。VAS上疼痛强度为4厘米时过冲和适应均最大。闭环系统产生的振荡压力在VAS上2、4和6厘米的强度下导致恒定而非适应性疼痛。袖带式压力痛觉计是一种高度可配置的工具，可通过压力-疼痛和时间-疼痛函数评估疼痛敏感性。所提出的模型是研究人员武器库中的有用补充，可用于进一步开展关于深部组织疼痛及相关机制的药理学和临床研究。
