Development and Validation of a Mortality Prediction Model for Patients Receiving 14 Days of Mechanical Ventilation

Abstract

Objectives-The existing risk prediction model for patients requiring prolonged mechanical ventilation is not applicable until after 21 days of mechanical ventilation. We sought to develop and validate a mortality prediction model for patients earlier in the ICU course using data from day 14 of mechanical ventilation.Study Design-Multi-center retrospective cohort study.Patients-Adult patients receiving at least 14 days of mechanical ventilation at 5 medical centers (development cohort) or enrolled in the ARDS Network FACTT trial (validation cohort). HHS Public Access Author Manuscript Author ManuscriptAuthor Manuscript Author ManuscriptMeasurements and Main Results-Predictor variables were measured on day 14 of mechanical ventilation in the development cohort and included in a logistic regression model with one-year mortality as the outcome. Variables were sequentially eliminated to develop the ProVent 14 model. This model was then generated in the validation cohort. A simplified prognostic scoring rule (ProVent 14 Score) using categorical variables was created in the development cohort and then tested in the validation cohort. Model discrimination was assessed by the area under the receiver-operator characteristic curve (AUC).491 patients and 245 patients were included in the development and validation cohorts, respectively. The most parsimonious model included age, platelet count, requirement for vasopressors, requirement for hemodialysis, and non-trauma admission. The AUC for the ProVent 14 model using continuous variables was 0.80 (95% CI, 0.76-0.83) in the development cohort and 0.78 (95% CI, 0.72-0.83) in the validation cohort. The ProVent 14 Score categorized age at 50 and 65 years old, and categorized platelet count at 100 × 10 9 /L, and had similar discrimination as the ProVent 14 model in both cohorts.Conclusion-Using clinical variables available on day 14 of mechanical ventilation, the ProVent14 model can identify patients receiving prolonged mechanical ventilation with a high risk of mortality within one year. KeywordsProlonged mechanical ventilation; outcomes; prognosis; critical care; communication; multiple organ failure; decision makingFor an increasing number of patients, critical illness or injury is neither self-limited nor imminently fatal 1 . As survival from life-threatening illness improves, pre-existing disease and newly-acquired organ dysfunction may conspire against recovery, leaving patients dependent on life supporting therapies for extended time periods. This syndrome, termed "chronic critical illness", is commonly typified by persistent respiratory failure that requires prolonged mechanical ventilation (PMV). Long-term mortality is high, approaching rates of 40% to 60% at one-year in inclusive cohorts [2][3][4][5][6][7][8][9][10] . Patients have a very high symptom burden during the weeks of prolonged ventilation 11,12 and chances of living at home with functional independence at the end of the year are as low as 10% 9,13 .Most PMV patients are unable to participate in thei...

Survey of Prolonged Mechanical Ventilation in Intensive Care Units in Mainland China

“…Consequently, we could not use the prognostic model proposed by Carson et al 23 to predict our subjects' 1-y mortality. 11 However, a comparison of subject characteristics is shown in table 1. Also, despite the small sample size and the design of our study, the risk factors for weaning that it revealed are consistent with current evidence; a follow-up study with a larger sample size is needed to verify our findings.…”

“…4 In 2005, Medicare-eligible patients who required PMV ranked third in summative in-patient charges by diagnostic groups and first in charges per patient. 9 Despite receiving such a high level of care, 29 -49% of PMV patients died in the hospital, 10,11 only 19% could be discharged home, 10 and Ͻ50% of PMV hospital survivors survived more than 1 y. 3,[10][11][12][13][14] Compared with withdrawal of ventilation, providing PMV to the basecase patient costs $55,460 per life-year gained and $82,411 per quality-adjusted life-year gained.…”

“…9 Despite receiving such a high level of care, 29 -49% of PMV patients died in the hospital, 10,11 only 19% could be discharged home, 10 and Ͻ50% of PMV hospital survivors survived more than 1 y. 3,[10][11][12][13][14] Compared with withdrawal of ventilation, providing PMV to the basecase patient costs $55,460 per life-year gained and $82,411 per quality-adjusted life-year gained. 9 As a high-cost population, patients who receive PMV should be a priority focus for hospital managers to control daily expenditures, and alternative care venues should be considered other than the ICU.…”

Survival, Outcomes, and Use of Acuity Scoring Systems Following Tracheotomy in Veteran Patients

“…We chose these scoring systems since they are established systems in the literature, are fairly easy to calculate and the data needed to calculate the scores is available in the medical record. The more recently described ProVent version 14 has only recently been validated outside of the cohort in which it was developed (patients who require prolonged mechanical ventilation), 17,19 so it was not considered in our study.…”

“…[14][15][16] However, there have been no reports of the use of these scoring systems in the subset of critically ill patients undergoing tracheotomy. 17 We undertook the following study to determine whether LODS and/or SOFA scores would be useful in the subpopulation of critically ill patients who undergo tracheotomy, to predict survival and other tracheotomy-specific outcomes. Our perception was that this subpopulation of patients for whom tracheotomy is requested had a worse outcome than the general population of critically ill patients.…”