CCCF Academy

Viau-Lapointe, J¹; Légaré, M²; Le Lorier J³.
¹PGY6 Adult Critical Care, University of Toronto, Toronto, Canada
²Critical Care and Pulmonary Medicine, Hôpital Maisonneuve-Rosemont, Montreal, Canada
³Centre de recherche du CHUM, Université de Montréal, Montreal, Canada
 

Introduction: Hospital length of stay before admission to the intensive care unit (ICU) has been reported as a risk factor for increased mortality in some cohort studies, however the underlying mechanism of this association has not been evaluated. Most of the data come from the United Kingdom where the limited availability of ICU beds drastically influence ICU outcomes compared to North America.
 
Objectives: The objectives of this study are to verify if an association exists between a prolonged hospital stay before ICU admission and an increased mortality in our ICU and explore if pertinent patient characteristics might explain the difference.
 
Methods: We undertook a retrospective cohort study from medical records of patients admitted to the medical ICU at Hôpital Maisonneuve-Rosemont in Montreal from January 2013 to December 2014. All patients admitted to the ICU 7 days or more after their hospital admission date (ward group) were matched 1:2 in a stratified sampling method to patients admitted the same month and year directly from the emergency room (emergency group). Data on patients demographics, diagnoses, comorbidities including Charlson comorbidity index, APACHE II score and level of care discussions were collected.
 
Results: During the study period, we studied 87 patients admitted from the ward and 174 patients admitted from the emergency room for a median length of stay of 3 days. From the ward patients, 80% were admitted for a new complication, most frequently respiratory failure or sepsis. The Charlson comorbidity index and APACHE II score were statistically higher in the ward group (p < .001). Hospital mortality was 47% in the ward group and 35% in the emergency group (p = .060) although the ICU mortality was the same (26 %). A univariate logistic regression analysis revealed that higher age, Charlson comorbidity index and APACHE II score or admission from the ward were associated with increasing hospital mortality. Multivariate analysis adjusted for those variables showed that the impact of the prior hospital stay and age becomes insignificant when adjusted for the other variables. During the course of the hospitalization, 41 % of patients admitted from the ward had comfort care initiated compared to 28 % of those admitted from the emergency (p = .032). These decisions were led by the ICU physicians in 85 % of the cases and occurred in 80 % of the deaths.
 
Conclusion: This study reveals a strong trend for higher hospital mortality in medical patients admitted to the ICU after a 7 days or more stay on the ward. The association disappears when adjusted for the Charlson cormorbidity index and APACHE II score suggesting that those factors explain the higher mortality. A significant proportion of the patients admitted from the medical ward had comfort care initiated in the ICU and died after discharge to ward. In many cases, the intensivist had a significant role in clarifying levels of care and such results may help orienting discussions on medical wards prior to ICU admission.

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