Validation of a Mortality Prediction Model for Prolonged Mechanical Ventilation

描述（由申请人提供）：许多患者在危重病的最初几天存活下来，但伴有多个残留器官衰竭。这些患者变得依赖于ICU中启动的机械通气和其他器官支持系统。需要长时间机械通气（PMV）的患者占机械通气患者的20%，并消耗所有ICU资源的40%。患者在疾病的最初严重阶段幸存下来，但他们仍然依赖生命支持系统，进展缓慢，并发症频繁。医生经常对PMV患者的预后感到困惑和不确定，因此他们通常不与患者家属分享预后信息。为了阐明这些复杂患者的预后，在一个三级医疗中心开发并验证了一个预后模型，该模型识别了3个月和1年时死亡风险高的PMV患者。该模型基于4个易于测量的变量，并转换为称为ProVent评分的临床预测规则。在考虑一般临床应用之前，需要对模型进行外部验证。本研究提出在两个外部队列中验证PMV预后模型，目的如下：1.在来自多个医疗中心的异质患者组中验证PMV预后模型和ProVent评分。2.评价ProVent评分的性能，并在PMV病程早期的患者中开发新模型。3.在急性肺损伤和急性呼吸窘迫综合征患者中验证ProVent评分。前两个目标的队列将由5家不同三级保健医院确定的600名连续PMV患者组成。数据将通过审查医疗记录获得，一年生存率将通过国家死亡指数确认。第二个队列将由NHLBI ARDS临床试验网络FACTT试验中接受PMV的所有患者组成。一个有效的PMV预后模型将允许研究人员在未来的PMV患者干预研究中标准化疾病的严重程度，并且临床上有用的预后评分将增强临床医生向患者和家属传达预后的信心。公共卫生相关性：许多重症患者需要数周或数月的机械通气，其中大量患者无法存活。一个评分系统，可以确定这些患者的死亡风险已经在一家医院开发。这项研究将确定该评分系统在美国其他医院需要长期机械通气的患者中是否准确。

DESCRIPTION (provided by applicant): Many patients who survive the first few days of critical illness do so with multiple residual organ failures. These patients become dependent on mechanical ventilation and other organ support systems initiated in the ICU. Patients requiring prolonged mechanical ventilation (PMV) account for up to 20% of mechanically ventilated patients and consume up to 40% of all ICU resources. The patients have survived the initial severe stages of their illness, yet they remain dependent on life support systems, progress is slow, and complications are frequent. Physicians are often confused and uncertain about prognosis for PMV patients, therefore they usually do not share prognostic information with patients' families. In order to clarify prognosis for these complicated patients, a prognostic model that identifies PMV patients who are at high risk of death at 3 months and 1 year was developed and validated at a single tertiary care medical center. This model is based upon 4 easily measured variables and converts to a clinical prediction rule called the ProVent Score. External validation of the model is required before general clinical application can be considered. This study proposes to validate the PMV prognostic model in two external cohorts with the following Aims: 1. To validate the PMV prognostic model and ProVent Score in a heterogeneous group of patients from multiple medical centers. 2. To evaluate the performance of the ProVent Score and develop new models in patients who are earlier in the course of PMV. 3. To validate the ProVent Score in patients with Acute Lung Injury and the Acute Respiratory Distress Syndrome. The cohort for the first two Aims will consist of 600 consecutive PMV patients identified at 5 diverse tertiary care hospitals. Data will be obtained by review of medical records, and one-year survival will be confirmed by the National Death Index. The second cohort will consist of all patients in the NHLBI ARDS Clinical Trials Network FACTT trial who received PMV. A valid PMV prognostic model will allow investigators to standardize illness severity in future studies of interventions for PMV patients, and a clinically useful prognostic score will enhance the confidence of clinicians in communicating prognosis to patients and families. PUBLIC HEALTH RELEVANCE: Many patients who become critically ill require mechanical ventilation for weeks or months, and a large number of them do not survive. A scoring system that can determine the risk of death for these patients has been developed in a single hospital. This study will determine if this scoring system is accurate in patients who require prolonged mechanical ventilation at other hospitals in the United States.