Relationship between volume and survival in closed intensive care units is weak and apparent only in mechanically ventilated patients.

BACKGROUND: Recent studies have found an association between increased volume and increased intensive care unit (ICU) survival; however, this association might not hold true in ICUs with permanent intensivist coverage. Our objective was to determine whether ICU volume correlates with survival in the Spanish healthcare system. METHODS: Post hoc analysis of a prospective study of all patients admitted to 29 ICUs during 3 months. At ICU discharge, the authors recorded demographic variables, severity score, and specific ICU treatments. Follow-up variables included ICU readmission and hospital mortality. Statistics include logistic multivariate analyses for hospital mortality according to quartiles of volume of patients. RESULTS: The authors studied 4,001 patients with a mean predicted risk of death of 23% (range at hospital level: 14-46%). Observed hospital mortality was 19% (range at hospital level: 11-35%), resulting in a standardized mortality ratio of 0.81 (range: 0.5-1.3). Among the 1,923 patients needing mechanical ventilation, the predicted risk of death was 32% (14-60%) and observed hospital mortality was 30% (12-61%), resulting in a standardized mortality ratio of 0.96 (0.5-1.7). The authors found no correlation between standardized mortality ratio and ICU volume in the entire population or in mechanically ventilated patients. Only mechanically ventilated patients in very low-volume ICUs had slightly worse outcome. CONCLUSION: In the currently studied healthcare system characterized by 24/7 intensivist coverage, the authors found wide variability in outcome among ICUs even after adjusting for severity of illness but no relationship between ICU volume and outcome. Only mechanically ventilated patients in very low-volume centers had slightly worse outcomes.

Ward mortality after ICU discharge: a multicenter validation of the Sabadell score.

BACKGROUND: Tools for predicting post-ICU patients' outcomes are scarce. A single-center study showed that the Sabadell score classified patients into four groups with clear-cut differences in ward mortality. OBJECTIVE AND DESIGN: To validate the Sabadell score using a prospective multicenter approach. SETTING: Thirty-one ICUs in Spain. PATIENTS AND METHODS: All patients admitted in the 3-month study period. We recorded variables at ICU admission (age, sex, severity of illness, and do-not-resuscitate orders), during the ICU stay (ICU-specific treatments, ICU-acquired infection, and acute renal failure), and at ICU discharge (Sabadell score). Statistical analyses included one-way ANOVA and multiple regression analysis with ward mortality as the dependent variable. RESULTS: We admitted 4,132 patients (mean age 61.5 +/- 16.7 years) with mean predicted mortality of 23.8 +/- 22.7%; 545 patients (13%) died in the ICU and 3,587 (87%) were discharged to the ward. Overall ward mortality was 6.7%; ward mortality was 1.5% (36/2,422) in patients with score 0 (good prognosis), 9% (64/725) in patients with score 1 (long-term poor prognosis), 23% (79/341) in patients with score 2 (short-term poor prognosis), and 64% (63/99) in patients with score 3 (expected hospital death). Variables associated with ward mortality in the multivariate analysis were predicted risk of death (OR 1.016), ICU readmission (OR 5.9), Sabadell score 1 (OR 4.7), Sabadell score 2 (OR 15.7), and Sabadell score 3 (OR 107.2). CONCLUSION: We confirm the ability of the Sabadell score at ICU discharge to define four groups of patients with very different likelihoods of hospital survival.