Type: retrospective observational multicenter trial. Population of interest: adult patients suffering from thoraco-abdominal trauma undergoing both non-operative and operative management.

Hypothesis: Adrenal gland injury is a rare finding after blunt thoracoabdominal trauma. Short-term outcomes of blunt adrenal gland injury (BAGI) described in literature are contradictory. Reports on the outcomes related to this injury are variable and consider heterogeneous populations of trauma patients Aim: This study aims to explore the burden related to BAGI in an homogeneous population of patients sustaining blunt thoraco-abdominal trauma treated in different institution

Adrenal gland injury is a rare finding after blunt thoracoabdominal trauma. The diagnosis can be accurately made with CT scan in stable patients, whilst in unstable patients, the detection can often be made during surgery, in the post-operative setting or postmortem. Short-term outcomes of blunt adrenal gland injury (BAGI) described in literature are contradictory. Studies reported BAGI as a high mortality risk injury. On the other hand, according to further reports, the presence of a BAGI is not considered a marker of severe injury or associated with an increased mortality rate.

Evidences the from a large multicenter cohort of selected trauma patients are lacking.

The study hypothesis is that BAGI is related to patients with higher trauma severity and worse overall outcome. By exploring the clinical burden related to BAGI the investigators aim to determine if this is related to the anatomical location of the injured organ or if in addition an underlying undisclosed pato-physiological mechanism is present. The investigatorspropose an international multicenter analysis on the epidemiology and the burden of BAGI in the context of major trauma, exploring differences between BAGI and non-BAGI patients.

Primary endpoint:

• Relationship between trauma severity (Injury Severity Score) of thoraco-abdominal trauma patients with BAGI versus torso trauma patients without BAGI

Secondary endpoint:

• Organ Injury Scale of the blunt adrenal trauma(OIS), overall survival, ICU length of stay, overall length of stay

Methods:

Patients will be enrolled according to the reported criteria. The following variables will be considered: - Demographic (age, sex, comorbidities) - Mechanism of trauma - Trauma bay and surgical management - Trauma severity (ISS, NISS, OIS, AIS) - Need for ventilation (Y/N, timing) - Data on vasoactive support - Post trauma clinical and laboratory parameters - Mortality - Length of stay (ICU, hospital) All information of patients will be extracted from our dedicated Trauma Registry and personal informations will be removed according to data anonymization, and collected in an electronic database.

Data will be reported in accordance with Strengthening the Reporting of Observational studies in Epidemiology guidelines (STROBE) for observational studies.

Statistical analysis A 1:1 propensity score matching analysis will be performed based on sex, setting of the trauma, trauma mechanism, age, ASA classification, intentionality of the trauma, Glasgow coma scale and Revised Trauma Score. Following the propensity score matching patients included with and without BAGI will be compared using χ2 test for categorical variables and t-student test or Mann-Whitney test according to sample distribution for continuous variables

Inclusion criteria:

• Age > 16 years old
• All patients with blunt thoraco-abdominal trauma

Exclusion criteria:

• TBI with AIS > 3
• Isolated TBI and Spinal cord injury
• Patients died in emergency department

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