Nursing technique for promoting wound healing of pressure ulcer-Development of a new animal model to elucidate effectiveness of shear to the wound healing-

政府在2002年引入了对不遵守压疮管理三项任务的处罚制度。由于该系统，成功地降低了PU的患病率，并缩短了愈合时间。然而，难熔脓液至今仍存在。PU愈合的延迟因素之一是剪切。剪切力不可避免地发生与护理干预，如定位患者在头部抬高的位置或位置的变化。在临床环境中，由于传感器有限，很难监测剪切力。因此，研究人员试图建立一种新的动物模型来阐明剪切对创面愈合的影响。首先，我们使用原始动物模型检测了剪切力强度与PU愈合之间的关系。8 kg的压力和0.5、1、1.5 kg的剪切向尾侧施加于侧腹区域6小时。高剂量组的创面愈合因组织坏死和浅性溃疡的发展而延迟。乳头状真皮扁平，红细胞外渗，血栓形成。到第14天，皮肤表面、皮下和肌肉层的胶原纤维平行坏死。其次，我们试图测量由压力和剪切载荷引起的发红强度。利用近红外装置和成像软磨损，将红度强度从主观值转换为客观值。坏死组织中近红外线通透性的相对值为31 ~ 71%。无坏死组织的创面为90 ~ 122%。根据这些结果计算预测效度，显示出较好的效度（符合率为75%）。此外，我们试图将动物模型的结果纳入到有限元模型中。在简单加载下完成了模型原型。

Government introduced penalty system for failure to comply with the three tasks for pressure ulcer (PU) management in 2002. Owing to this system, the prevalence of PU successfully reduced and a healing time was also shortened. However, refractory Pus have remained to date. One of the delayed factors for PU healing is shear. Shear forces occur inevitably with nursing interventions such as positioning patients in head-elevated positions or position changes. In clinical settings, it is very difficult to monitor shear forces because of a limited sensor. Thus, researches try to develop a new animal model to elucidate effectiveness of shear to the wound healing. Firstly, we examined the relationship between the intensity of the shear force and PU healing using our original animal model Eight kg of pressure and 0.5, 1, 1.5 kg shear toward the caudal side were applied for 6 hours to the flank region. The higher group's wound healing was delayed by the necrotic tissue and the shallow ulcer development. Papillary dermis was flat and extravasations of red blood cells and thrombosis were seen. Collagen fibers in the dermis paralleled skin surface and subcutaneous and muscle layer necrosis were seen up to Day 14. Secondarily, we tried to measure the intensity of redness resulting from pressure and shear loading. Using a near-infrared device and an imaging soft wear, we converted the intensity of the redness from subjective values to objective values. The relative values of permeability of near-infrared rays in the necrotic tissues were 31 -71%. While those in the wound without necrotic tissue were 90-122%. According to these results, the predictive validity was calculated and demonstrated good validity (agreement rate: 75%). Moreover, we tried to incorporate the animal model results into a finite element model. A prototyped model was completed under the simple loading.