Frantz R A, Xakellis G C
College of Nursing, University of Iowa, Iowa City 52242.
Am J Phys Med Rehabil. 1989 Dec;68(6):272-6. doi: 10.1097/00002060-198912000-00003.
Although laboratory studies have documented that externally applied pressure disrupts circulation, in clinical practice little is known about the characteristics of blood flow over bony prominences as a function of time. The purpose of this study was to describe the pattern of blood flow over the trochanter when subjected to a constant interface pressure for a prolonged period of time. A quasi-experimental design was used to measure skin blood flow over the left trochanter in a sample of 19 healthy adults. With the use of laser doppler flowmetry, the pattern of blood flow was monitored continuously while subjects lay on a supportive air mattress. Measurement of blood flow was described for three periods: preload with subjects supine, loading with subjects in the left lateral position and hyperemia after subjects returned to the supine position. Rate of blood flow under loading showed a gradual increase from preload. There was a marked initial increase in flow during hyperemia that gradually tapered off, but failed to reach preload levels within 30 min. Individual blood flow tracings revealed an inconsistent pattern of response to loading, suggesting the presence of a range of physiological response to compressive surface pressure. Given the individual variation in response to a common external pressure, further research is recommended to evaluate the pattern of blood flow over bony prominences subjected to known interface pressure.
尽管实验室研究已证明外部施加压力会扰乱血液循环，但在临床实践中，对于骨隆突处血流特征随时间的变化情况却知之甚少。本研究的目的是描述在长时间承受恒定界面压力时，大转子处的血流模式。采用准实验设计，对19名健康成年人样本的左大转子处皮肤血流进行测量。使用激光多普勒血流仪，在受试者躺在支撑性气垫上时持续监测血流模式。对三个阶段的血流进行了测量：受试者仰卧时的预负荷阶段、受试者左侧卧位时的负荷阶段以及受试者恢复仰卧位后的充血阶段。负荷状态下的血流速率从预负荷阶段开始逐渐增加。充血阶段血流最初显著增加，随后逐渐减少，但在30分钟内未恢复到预负荷水平。个体血流描记显示对负荷的反应模式不一致，表明对压迫性表面压力存在一系列生理反应。鉴于对共同外部压力的个体反应存在差异，建议进一步研究以评估在已知界面压力下骨隆突处的血流模式。
