Prevention MODS by modulating the inflammatory response through

INTERVENTION: Product Name: MELATONIN INJECTABLE Pharmaceutical Form: Solution for injection INN or Proposed INN: Melatonin CAS Number: 73‐31‐4 Current Sponsor code: EC 08/00230 Other descriptive name: MELATONIN Concentration unit: mg milligram(s) Concentration type: equal Concentration number: 60‐ Pharmaceutical form of the placebo: Solution for injection Route of administration of the placebo: Intravenous use CONDITION: Septic patients of abdominal surgery Therapeutic area: Analytical, Diagnostic and Therapeutic Techniques and Equipment [E] ‐ Surgical Procedures, Operative [E04] PRIMARY OUTCOME: Main Objective: Primary objective: To reduce the incidence of multiple organ dysfunction syndrome (MODS) in; abdominal surgery patients with severe sepsis Primary end point(s): ASSESSING inflammatory and immunological response: During the days 0; (pre‐surgery and after administration of melatonin or placebo) and at 1, 2, 3, 4 and 5 days after the surgical intervention will be the determination of plasma levels of cytokines (IL‐2, IL‐4, IL ‐6, IL‐10, TNF‐a and IFN‐g), and protein markers of apoptosis (sFas, FasL, sFasL, caspase‐3, Bcl‐2, and PARP), antioxidant enzymes (superoxide dismutase, SOD), catalase glutathione peroxidase and glutathione reductase) and the levels of lipid peroxidation (malondialdehyde). Also at the same time study will be conducted to determine blood count and differential count.; Assessment of the functionality of various organic by biochemical systems in plasma obtained from blood samples parameters of transaminases (GOT,; GPT, GGT), total and direct bilirubin, LDH, urea and creatinine. As levels of calcium, sodium, potassium and chloride. Secondary Objective: Objective: 1) To study the inflammatory response by measuring cytokine; index of lipid peroxidation (levels of malondialdehyde) in the study groups: melatonin,; placebo and reference. 2) To evaluate clinical and immunological response resulting from administration of; melatonin. 3) Evaluate the degree of organ dysfunction developed in the patients studied. 4); To study the correlation between the treatment given, the modulation of the parameters studied; and the development of MODS. Timepoint(s) of evaluation of this end point: Clinical evaluation: To evaluate the clinical outcome of patients and; functional status of their organ systems in the days after surgery, was; use the rating scale of multiple organ dysfunction syndrome associated with sepsis; (SOFA) every 24 hours during the study period. INCLUSION CRITERIA: Patients who are in clinical status from "severe sepsis" according to the diagnostic criteria "American College of Chest Physicians / Society of Critical Care Medicine" (Annex I), ie patients with systemic inflammatory response syndrome associated to infectious etiology dysfunction organic, hypoperfusion or hypotension, and will undergo surgery. Are the trial subjects under 18? no Number of subjects for this age range: F.1.2 Adults (18‐64 years) yes F.1.2.1 Number of subjects for this age range 40 F.1.3 Elderly (>=65 years) no F.1.3.1 Number of subjects for this age range SECONDARY OUTCOME: Secondary end point(s): ASSESSING inflammatory and immunological response: During the days 0; (pre‐surgery and after administration of melatonin or placebo) and at 1, 2, 3, 4 and 5 days after the surgical intervention will be the determination of plasma levels of cytokines (IL‐2, IL‐4, IL ‐6, IL‐10, TNF‐a and IFN‐g), and protein markers of apoptosis (sFas, FasL, sFasL, caspase‐3, Bcl‐2, and PARP), antioxidant enzymes (superoxide dismutase, SOD), catalase glutathione peroxidase and glutathione reductase) and the levels of lipid peroxidation (malondialdehyde). Also at the same time study will be conducted to determine blood count and differential count.; Assessment of the functionality of various organic by biochemical systems in plasma obtained from blood samples parameters of transaminases (GOT,; GPT, GGT), total and direct bilirubin, LDH, urea and creatinine. As levels of calcium, sodium, potassium and chloride. Timepoint(s) of evaluation of this end point: Clinical evaluation: To evaluate the clinical outcome of patients and; functional status of their organ systems in the days after surgery, was; use the rating scale of multiple organ dysfunction syndrome associated with sepsis; (SOFA) every 24 hours during the study period.