Subcutaneous oxytocin administration before a surgical incision to reduce pain

INTERVENTION: All patients receive standardised anesthetic induction and mantainence. The patients are randomly assigned to one of three groups using block randomization: 1. The oxytocin group 2. The lidocaine group 3. The control group. The oxytocin group receive subcutaneous oxytocin (oxitopisa® 5 UI 4 µg in 4 ml, diluted in saline) before the incision in the surgical site for the placement of three or four trocars. The lidocaine group receive subcutaneous lidocaine 1% (pisacaina 1% R 4 ml) infiltration. The control group do not receive any treatment at the surgical site. The experimental drugs are given once. The patients and anesthesiologists are blinded to the composition of the injected solution. In al groups, the following parameters are recorded with a GE Health Care model Datex Ohmeda S5 monitor during the operation: 1. Heart rate 2. Non‐invasive blood pressure (systolic, diastolic and mean) 3. Pulse oximetry 4. End‐tidal CO2 These parameters are recorded during the entire procedure but are documented specifically at the following points: 1. Basal 2. Anesthetic induction 3. Post‐intubation (correspondent to drug infiltration) 4. Surgical incision 5. Transoperative (insufflation of pneumo‐peritoneum) 6. Anesthetic emersion Any requirement for intraoperative salvage administration of fentanyl as a response to increased blood pressure (>20%) is also documented. Post‐operative pain at rest is recorded using the visual analogue scale after the patient's admission to and discharge from the post‐anesthetic care unit (PACU) and during hospitalisation 24 hours after surgery. The occurrence of adverse events is also assessed througho CONDITION: Laparascopic surgery, hemodynamic nociceptive automatic response and post‐surgical pain ; Surgery ; Laparascopic surgery, hemodynamic nociceptive automatic response and post‐surgical pain PRIMARY OUTCOME: ; 1. Nociceptive hemodynamic response to surgical incision recorded as the change in the heart rate, diastolic and systolic blood pressure, measured using a GCE Healthcare model Datex Ohmeda S5 monitor during the surgical procedure; 2. Post‐surgical pain level, assessed using a visual analogue scale (VAS) at the post‐anesthetic care unit arrival, post‐anesthetic care unit discharge and during hospitalisation; SECONDARY OUTCOME: ; Incidence of adverse effects and side effects, monitored throughout the study and additionally assessed by a post‐operative evaluatiob by the surgeon 7‐10 days after surgery; INCLUSION CRITERIA: 1. Aged 18‐75 2. ASA (American Society of Anesthesiologists) Hazard Scale I or ASA II 3. Undergoing scheduled laparoscopic surgery