Therefore, the aim of this study was to measure HMGB1 levels in circulating next monocytes as well as in the serum of patients undergoing elective surgical trauma. In addition, we evaluated a possible relationship between HMGB1 and Interleukin-6 (IL-6) production, since IL-6 is a key cytokine involved in surgical stress response.Materials and methodsPatientsFollowing approval by the Human Subjects Review Committee and the Research Ethics Board, 47 adult subjects, American Society of Anesthesiologists (ASA) physical status I and II, scheduled for major abdominal procedures, were included in a prospective study. Patients with diabetes, cardiac, pulmonary, renal, vascular, immunologic, neurodegenerative, infectious or hepatic diseases were excluded from the study.

Subjects who were taking medication known to interfere with hormonal, metabolic or immunological function as well as pregnant or breast feeding women were also excluded.Written informed consent was obtained from eligible patients during the screening period, at which time physical examination and medical history were evaluated. Postoperative complications were recorded throughout seven post-surgery days. Fifteen control subjects matched for sex, age and weight were also enrolled. Informed consent was obtained from the control subjects as well as the patients.Anesthesia techniqueAfter intravenous medication with midazolam (0.025 mg/Kg), all patients received a standard general anesthesia protocol. Anesthesia induction was performed by thiopentone sodium (5 mg/Kg) and fentanyl (1.4 ��g/Kg). Vecuronium (0.

08 mg/Kg) was injected to facilitate orotracheal intubation during direct laryngoscopy.Anesthesia was maintained with 60% air in oxygen supplemented with 1 to 2.5% inspired concentration of sevoflurane, fentanyl and vecuronium administered according to clinical need. In all patients a radial artery catheter was inserted for continuous monitoring of arterial blood pressure.In addition, standard parameters such as electrocardiogram (ECG), oxygen saturation (SaO2), End-Tidal carbon dioxide (ETCO2) and hemoglobin (HB) were measured during surgery. All patients’ lungs were mechanically ventilated by means of S/5 AVANCE device (Datex-Ohmeda, Helsinki, Finland) with the goal of achieving an ETCO2 level of 38 to 40 mmHg. Normal saline and Ringer Lactate solutions were administered with the infusion rate being adjusted from 6 to 10 ml/Kg/h according to blood loss.

Rectal temperature was maintained at 37��C by warming fluids before administration and using an upper body Bair Hugger (Arizant Brefeldin_A Healthcare Inc., Eden Prairie, MN, USA). Duration of both surgery and anesthesia was recorded. The same surgical team performed all operative procedures.After surgery neuromuscular blockade was antagonized with 0.5 to 1.5 mg atropine and 1 to 2.5 mg intrastigmine. Post-operative pain relief was provided by intravenous morphine bolus administered (0.