Effect of Backrest Elevation on Skin Integrity in the Critically Ill

描述（由申请人提供）：压疮（PU）和呼吸机相关性肺炎（VAP）通常作为危重患者的医源性并发症发生，导致发病率、死亡率和医疗保健费用增加。在机械通气患者中，预防这些并发症的策略存在冲突。建议降低压疮（PU）风险，将患者置于靠背位置小于30度，而降低VAP风险的干预措施将患者置于靠背位置大于30度。虽然有充分的证据表明较高的靠背高度会降低VAP，但几乎没有经验证据说明这些较高的靠背位置（30度或更大）对影响PU形成和组织完整性的因素的影响。本描述性纵向研究在重症机械通气成人中进行，目的是1）描述靠背抬高对皮肤压力和剪切力的影响，2）描述靠背抬高对组织完整性的影响。次要目的是评价内在（患者）因素（人口统计学、生理状态、支撑表面、活动性）对外在因素（压力、剪切力、湿度）和组织完整性的影响。将在24个月期间入组来自3个成人ICU的共计150例受试者。靠背高度、压力和剪切力将连续测量72小时。靠背高度将使用测斜仪装置测量，压力和剪切力将使用Xcampus压力测绘系统测量。使用NPUAP分期系统和组织损伤测量（EPISCAN），通过皮肤观察每12小时测量一次组织完整性。将通过处理后的EEG（PSI）连续测量镇静水平（持续72小时），并记录患者运动（腕动记录仪）。还将获得疾病严重程度（APACHE III）、营养状态（前白蛋白）和支撑表面类型。所有数据将由研究小组成员收集，并下载到计算机进行分析。逐步、多变量重复测量模型将用于描述升高水平、皮肤压力、剪切力和组织完整性随时间的关系。这项研究将为我们理解导致危重患者组织损伤的压力水平和持续时间以及PU发展的经验基础做出重大贡献。 公共卫生相关性：压疮经常发生在危重病人中。使用升高的靠背位置有助于减少这一人群的肺炎，但也可能增加压疮。本研究将评估使用抬高的靠背位置，以确定其对组织和皮肤完整性的影响。还将探讨可能影响人群中压疮风险的因素。

DESCRIPTION (provided by applicant): Both pressure ulcers (PUs) and ventilator associated pneumonia (VAP) commonly occur as iatrogenic complications in the critically ill, resulting in increased morbidity, mortality, and health care costs. In mechanically ventilated patients, strategies to prevent these complications are in conflict. Recommendations to reduce pressure ulcer (PU) risk place patients in backrest positions of less than 30 degrees while interventions to reduce VAP risk place patients in backrest positions of greater than 30 degrees. Although it is well documented that higher backrest elevations reduce VAP, there is little empirical evidence that describes the effect of these higher backrest positions (30 degrees or greater) on factors affecting PU formation and tissue integrity. The purpose of this descriptive, longitudinal study in critically ill mechanically ventilated adults is to 1) describe the effect of backrest elevation on skin pressure and sheer force and, 2) describe the effect of backrest elevation on tissue integrity. A secondary aim will evaluate the effect of intrinsic (patient) factors (demographics, physiologic status, support surface, mobility) on extrinsic factors (pressure, shear, moisture) and tissue integrity. A total of 150 subjects from 3 adult ICUs will be enrolled over a 24 month period. Backrest elevation, pressure and shear force will be measured continuously for 72 hours. Backrest elevation will be measured using an inclinometer device and pressure and shear will be measured using the XSENSOR pressure mapping system. Tissue integrity will be measured every 12 hours by skin observation using the NPUAP Staging System and a measure of tissue injury (EPISCAN). Sedation level will be continuously measured (for 72 hours) by processed EEG (PSI) and patient movement (wrist actigraphy) will be documented. Severity of illness (APACHE III), nutritional status (prealbumin) and type of support surface will also be obtained. All data will be collected by research team members and downloaded to a computer for analysis. Stepwise, multivariate repeated measures models will be used to describe the relationships among elevation levels, skin pressure, shear force and tissue integrity over time. This study will make a significant contribution to our understanding of pressure levels and duration that result in tissue injury in the critically ill and to the empirical base of PU development. PUBLIC HEALTH RELEVANCE: Pressure ulcers occur often in the critically ill. Use of elevated backrest positions are helpful to reduce pneumonia in this population but may also increase pressure ulcers. This study will evaluate use of elevated backrest position to determine its effect on tissue and skin integrity. Factors that may influence pressure ulcer risk in the population will also be explored.