Procedures
Anesthesia
The anaesthetic protocol was standardized for all patients. Basic monitoring (pulse oximeter, electrocardiogram, non-invasive arterial blood pressure, and end-tidal Co2) was attached. IV access was inserted and 500 ml of normal saline was given preoperative. Anesthesia was induced with fentanyl (Fentanyl Hamein, Sunny Pharmaceutical, Germany) 2 µg/kg, propofol (Propofol 1%, Fresenius Kabi, Deutschland) 1–2 mg/kg, lidocaine 1.5 mg/kg and rocuronium (Esmerone, Organon, The Netherlands) 0.5 mg/kg was administered to facilitate endotracheal intubation. Anesthesia and muscle relaxant were maintained by isoflurane 1 to 1.5 MAC (minimum alveolar concentration) in a 50% oxygen/air mixture and rocuronium 0.15 mg/kg respectively. Additional intraoperative analgesia consisting of IV boluses of 25 µg fentanyl was given as determined by fluctuation in vital signs (increasesd in heart rate > 20% above the basal value). At the end of the surgery, a dose of paracetamol 1 gm/100 ml IV was given to all patients before extubation. Intravenous neostigmine (0.05 mg/kg) and atropine (0.01 mg/kg) were administered to reverse muscle relaxants.After extubation, patients were transferred to the post-anesthesia care unit (PACU), where a standard analgesic regimen of paracetamol 1 g was given intravenously every 8 h. to all patients. In addition, an intravenous PCA morphine bolus of 3 mg without background infusion and a lockout period of 15 min were given upon patient’s request during the follow up period.