This multicenter cohort aims to assess the impact of within-hospital trajectories of patients admitted in intensive care units from emergency departments on vital prognosis of patients, duration of hospital stay and hospital costs.

As secondary objectives, the study will:

• assess the impact of clinical and demographic characteristics on hospital trajectories of patients.
• assess the impact of emergency units workload, beds availability in medical units and in intensive care units, and global hospital organisation on patients care trajectories.

The study will be performed in emergency departments and ICUs of university hospitals. 15 emergency departments and 36 ICUs of APHP (the public hospital system of the city of Paris) will be involved.

The study will assemble the data from 50,000 to 80,000 patients in total.

Eligible patients are admitted in ICUs between 01/01/2007 and 12/31/2011.

Extraction of the patients' data will be performed with processing software utilised in APHP, i.e. Healthcare Information System Program (PMSI, Urqual, Gilda...etc.).

Collected patients' data span the period from admission in emergency department or medical department unitl hospital discharge.

Inclusion Criteria:

• Adult patient directly admitted in ICU from emergency departments of APHP (the public hospital system of the city of Paris).
• Adult patient indirectly transferred to ICU from an hospitalization unit, initially admitted from an emergency department of APHP.

Exclusion Criteria:

• Patient transferred from APHP toward an external hospital, outside APHP, before being admitted in an ICU.

The population under study is formed of patients admitted in 3 types of intensive care units (Medical intensive care unit, Surgical Intensive Care Unit and Cardiac Intensive Care Unit), transferred from emergency departments, either directly, or from another Department such as a Unit of short durations of hospitalization.