age limit: between 18 years to 80 years; gender: male and female; within 2 hours of surgical intervention; ASA physical status I, II, III; written consent accepted to be enrolled in the study; in polytrauma patients in the operation theatre who are brought directly through the emergency department, written consent is obtained from the relatives, in accordance to the national law number 206, of 2004, for a good and correct scientific research, in the situation where the patient is no capable to sign or give the written consent;