Determinants of postintensive care unit mortality: a prospective multicenter study

Abstract

Objective: Six to 25 percent of patients discharged alive from the intensive care unit (ICU) die before hospital discharge. Although this post-ICU mortality may indicate premature discharge from a full ICU or suboptimal management in the ICU or ward, another factor may be discharge from the ICU as part of a decision to limit treatment of hopelessly ill patients. We investigated determinants of post-ICU mortality, with special attention to this factor.

Design: Prospective, multicenter, database study.

Setting: Seven ICUs in or near Paris, France.

Patients: A total of 1,385 patients who were discharged alive from an ICU after a stay of > or = 48 hrs; 150 (10.8%) died before hospital discharge. Decisions to withhold or withdraw life-sustaining treatments were implemented in the ICUs in 80 patients, including 47 (58.7%) who died before hospital discharge.

Interventions: None.

Measurements and main results: In the univariate analysis, post-ICU mortality was associated with advanced age, poor chronic health status, severe comorbidities, severity and organ failure scores (Simplified Acute Physiology Score II, sepsis-related organ failure assessment, and Logistic Organ Dysfunction at admission and at ICU discharge), decisions to withhold or withdraw life-sustaining treatments, and Omega score (reflecting ICU resource utilization and length of ICU stay). Multivariate stepwise logistic regression identified five independent determinants of post-ICU mortality: McCabe class 1 (odds ratio, 0.388 [95% confidence interval, 0.26-0.58]), transfer from a ward (odds ratio, 1.89 [95% confidence interval, 1.27-2.80]), Simplified Acute Physiology Score II score at admission >36 (odds ratio, 1.57 [95% confidence interval, 1.6-2.33]), decisions to withhold or withdraw life-sustaining treatments (odds ratio, 9.64 [95% confidence interval, 5.75-16.6]), and worse sepsis-related organ failure assessment score at discharge (odds ratio, 1.11 [95% confidence interval, 1.03-1.18] per point).

Conclusions: More than 10% of ICU survivors died before hospital discharge. Determinants of post-ICU mortality included variables reflecting patient status before and during the ICU stay. However, the most powerful predictor of post-ICU mortality was the decision to withhold or withdraw life-sustaining treatments in the ICU, suggesting that the decision has been made not to use the unique services of the ICU for these patients.