*9.1.6 Systemic inflammatory response syndrome (SIRS)*

**SIRS/SEPSIS** was defined as the set of systemic manifestations that represent the systemic response of the body to inflammation or infection, expressing the concept of serial reactions to injury, depending on the individual characteristics, regardless of the original cause. It was defined as the presence of two or more of the following signs: body temperature above 38°C or below 36°C, heart rate above 90/min, hyperventilation [respiratory rate (RR) above 20/min or PaCO2 below 32 mmHg), with a serum WBC higher than 12,000 cells/μL or lower than 4000/μL. Alterations in consciousness, presence of significant edema (or a positive fluid balance above 20 ml/kg), and hyperglycemia (higher than 120 mg/dl, without previous diabetes) were included posteriorly to the initial concept. Quick SOFA (Sequential [Sepsisrelated] Organ Failure Assessment) was introduced. This score would allow prompt identification of suspected cases of infection that had the risk of adversely evolving to sepsis. Patients are at risk if they presented at least two out of the following criteria: RR ≥ 22/min, alterations in consciousness (Glasgow Coma Scale ≤13), and systolic arterial pressure ≤ 100 mmHg. The usefulness of the concept of SIRS/SEPSIS lies in its sensitivity to identify early responses, timely warning clinicians for the possibility of sepsis.

### **9.2 Analytical parameters**

Plasma biomarkers, such as white blood count (WBC), the eosinophil cells count (ECC), plasma C-reactive protein (CRP), procalcitonin (PCT) and calprotectin (CLP) for identifying CAL-patients, and the usefulness of cut-off values of CRP, PCT, and CLP for early discharge of patients, considering the routine adoption of enhanced recovery programs. These parameters increased their sensitivity and specificity for CAL detection when used together.
