Weaning from Prolonged Mechanical Ventilation

说明(申请人提供)：需要机械通气(MV)超过21天的患者占ICU总费用的37%以上。因此，这些患者现在被转移到专门从事MV撤机的中心，即所谓的长期急性护理(LTAC)设施。尽管LTAC设施激增，但缺乏可靠地确定哪些患者可能脱机的测试研究，以及加快脱机的方法。此外，在延长MV疗程后，很少或根本没有关于生存、家庭出院和患者对生活质量(QOL)的感觉的决定因素的信息。因此，这项建议的目的是确定最有效的方法来撤除需要长时间机械通气(定义为21天)并已被转移到LTAC机构的患者，并确定哪些患者可能脱离机械通气。第二个目的是确定预测LTAC设施存活和出院的因素，以及延长机械通气对功能状态和生活质量的长期影响。为了达到这些目的，将在转到LTAC设施的患者中进行前瞻性随机试验，以比较两种脱机技术的效果：压力支持试验和自主呼吸试验。还将测量人口统计学、生理、心理和一般健康状况，以检验这些测量在预测断奶结果、存活率和家庭出院方面的准确性。出院后6个月和12个月，将在LTAC设施和患者居住地测量呼吸肌力量、握力及其与患者对功能状态和生活质量的感知的关系。这项提案的发现将为预测哪些患者可以脱机并存活到出院的最可靠方法、最有效的脱机方法以及延长机械通气对长期生活质量和功能状态的影响提供新的见解。这些信息将首次为卫生保健提供者提供可靠的科学证据，并帮助他们制定客观的指导方针，以管理在LTAC设施中断奶的患者。

DESCRIPTION (provided by applicant): Patients requiring mechanical ventilation (MV) for more than 21 days account for more than 37% of all ICU costs. As such, these patients are now transferred to centers that specialize in weaning from MV, so called long-term acute care (LTAC) facilities. Despite the proliferation of LTAC facilities, research on tests that reliably identify which patients are likely to wean and methods for expediting weaning are lacking. In addition, little or no information is available regarding the determinants of survival, home discharge, and patient's perception of quality of life (QOL) after a prolonged course of MV. Thus, the aim of this proposal is to determine the most efficient way to wean patients who require prolonged MV (defined as >21 days) and have been transferred to an LTAC facility and to identify which patients are likely to wean from MV. The secondary aim is to determine the factors that predict survival and home discharge from a LTAC facility and the long-term impact of prolonged MV on functional status and QOL. To address these aims, a prospective, randomized trial in patients who are transferred to a LTAC facility will be done to compare the efficacy of two weaning techniques: pressure support and spontaneous breathing trials. Demographics, physiological, psychological, and general health status will also be measured to examine the accuracy of such measurements in predicting weaning outcome, survival, and home discharge. Respiratory muscles strength, handgrip strength, and their relationship to patient perception of functional status and QOL will be measured at the LTAC facility and the patient place of residence at 6 and 12 months after discharge. Findings from this proposal will provide novel insights into the most reliable means for predicting which patients can wean and survive to be discharged home, the most efficient method of weaning patients, and the impact of prolonged MV on long-term QOL and functional status. Such information will provide for the first time solid scientific evidence to health care providers, and help them formulate objective guidelines for the management of patients being weaned at a LTAC facility.