Induction of anesthesia was performed with remifentanil, pentothal 3 mg/kg and atracurium 0.5 mg/Kg. Anaesthesia was maintained with remifentanil (0.4 ug/Kg/min) and isoflurane adjusted to bispectral index (40-60). Patients received a phenylephrine infusion to maintain systolic blood pressure (SBP) 20% to 30% under baseline. The lower limit of SBP was 75 mmHg. In the recovery room, morphine was administered routinely at doses of 3 mg IV every 15 minutes until pain was less than 4 estimated by visual analog scale (VAS). VAS and pain threshold with von Frey filaments were assessed at 2, 6, 12 and 24 postoperative hours. All patients, received ketorolac 30 mg IV every 8 hours and intravenous morphine administered by patient controlled analgesia system (PCA) during the first 24 hours.

Induction of anesthesia was performed with remifentanil, pentothal 3 mg/kg and atracurium 0.5 mg/Kg. Anaesthesia was maintained with remifentanil (0.4 ug/Kg/min) and isoflurane adjusted to bispectral index(40-60). Patients received a phenylephrine infusion in order to maintain systolic blood pressure (SBP) 20% to 30% over baseline. The upper limit of SBP was 165 mmHg. In the recovery room, morphine was administered routinely at doses of 3 mg IV every 15 minutes until pain was less than 4 estimated by visual analog scale (VAS). VAS and pain threshold with von Frey filaments were assessed at 2, 6, 12 and 24 postoperative hours. All patients, received ketorolac 30 mg IV every 8 hours and intravenous morphine administered by patient controlled analgesia system (PCA) during the first 24 hours.

Patients were assigned to receive a phenylephrine infusion in order to maintain systolic blood pressure (SBP) 20% to 30% over the baseline. The upper limit of systolic blood pressure is 165 mmHg.

Measure of morphine consumption during the first 24 postoperative hours in patients undergoing laparoscopic cholecystectomy.