Patients-Controlled Epidural Analgesia After Gastric Bypass for Morbid Obesity Using Morphine-Levobupivacaine Regimens

• Change from baseline of Spirometric values [ Time Frame: up to 6 days ] [ Designated as safety issue: Yes ]
  Spirometric values (FVC, FEV1, FEV1/FVC, MEF50, MER25-75, PEF)at 4, 6, 12, 24, 36, 48, 72, 96, 144 hours postoperatively
• Bowel recovery [ Time Frame: up to 6 days ] [ Designated as safety issue: Yes ]
  Recovery of bowel function assessed by first flatus or stool, noticed by the patient
• Change from baseline of hemodynamics profile [ Time Frame: up to 48 hours ] [ Designated as safety issue: Yes ]
  Measurement of arterial pressure (mmHg), heart rate (bpm)at 5, 30, 45 minutes and 1, 2, 4, 6, 12, 24, 36, 48 hours postoperatively

Adequate postoperative analgesia can facilitate recovery following gastric bypass surgery for morbid obesity. The efficacy and safety of intravenous patient - controlled analgesia has been studied, but up to date no data are available concerning the use of thoracic epidural patient-controlled analgesia regarding the use of levobupivacaine combined with morphine in morbidly obese patients. The investigators' aim in this prospective, randomized, double-blinded study was to compare the analgesic effectiveness, the dose requirements and side effects of thoracic epidural infusion of bolus doses of 0,1% and 0,2% levobupivacaine combined with a continuous administration of morphine, after open gastric bypass for morbid obesity.

Morbidly obese patients (BMI > 50 kg/m2) planned to undergo open Bili pancreatic diversion with R-en-Y gastric bypass (BPD R-en-Y gastric bypass ) or Bili pancreatic diversion (BPD) procedure, will be managed with standardized general anesthesia (intravenous Propofol combined with fentanyl and muscle relaxation). Preoperatively, in all patients an epidural catheter in the thoracic spine level will be placed between T5 and T8. All patients will be randomly allocated to six groups:

Group A patients (control group) will receive intra-operatively (45 min before the estimated end of the surgery) a bolus dose 2 ml of normal saline. Postoperatively, immediately after extubation patient controlled epidural anesthesia (PCEA) using a continuous epidural infusion of morphine 0,2 mg/h, combined with 0,1% levobupivacaine (5ml, lockout interval 10min) will be administered, Group B patients will receive a bolus dose of 1mg of morphine intra-operatively (45 min before the estimated end of the surgery) and postoperatively the same levobupivacaine and morphine regimen as Group A, Group C patients will receive a bolus dose 2 mg of morphine intra-operatively and thereafter the same levobupivacaine and morphine regimen as Group A, Group D patients will receive intra-operatively a bolus dose of 2 ml of normal saline. Postoperatively, the patients will receive PCEA in a dose of 0,2% levobupivacaine (5ml, lockout interval 10min) combined with a continuous epidural infusion of morphine 0,2 mg/h, Group E patients will receive intra-operatively a bolus dose of 1mg of morphine intra-operatively and postoperatively the same regimen as Group D.

Group F patients will receive intra-operatively a bolus dose of 2 mg of morphine intra-operatively and thereafter the same regimen as Group D.

Pain assessment will be performed using visual analogue scale (VAS, 10cm scale) at rest, at mobilization and at cough. Furthermore, total local anesthetic and morphine consumption, side effects on cardiovascular, respiratory and gastrointestinal systems, including blood pressures, blood gases, spirometric values (FEV1, FVC, FEV1/FVC), incidents of PONV, prutitus, time to first flatus, motor blockage and length of hospital stay will be recorded for the first postoperative 48h.

• Morbid Obesity
• Postoperative Pain

• Drug: EPIDURAL 0 mgMORPHINE- 0,1%CHIROCAINE
  Patients will receive intra-operatively (45 min before the estimated end of the surgery) a bolus dose 2 ml of normal saline. Postoperatively, immediately after extubation patient controlled epidural anesthesia (PCEA) using a continuous epidural infusion of morphine 0,2 mg/h, combined with 0,1% levobupivacaine (5ml, lockout interval 10min) will be administered
  Other Names:

  • Morfina cloridrato 10 mg /ml - Morphine
  • Chirocaine 5 mg/ml - Levobupivacaine
• Drug: EPIDURAL 1 mg MORPHINE- 0,1% CHIROCAINE
  Patients will receive intraoperatively a bolus dose of 1mg of morphine (45 min before the estimated end of the surgery) and postoperatively,immediately after extubation patient controlled epidural anesthesia (PCEA) using a continuous epidural infusion of morphine 0,2 mg/h, combined with 0,1% levobupivacaine (5ml, lockout interval 10min) will be administered
  Other Names:

  • Morfina cloridrato 10 mg /ml - Morphine
  • Chirocaine 5 mg/ml - Levobupivacaine
• Drug: EPIDURAL 2 mg MORPHINE - 0,1%CHIROCAINE
  Patients will receive intraoperatively a bolus dose 2 mg of morphine and postoperatively, immediately after extubation patient controlled epidural anesthesia (PCEA) using a continuous epidural infusion of morphine 0,2 mg/h, combined with 0,1% levobupivacaine (5ml, lockout interval 10min) will be administered
  Other Names:

  • Morfina cloridrato 10 mg /ml - Morphine
  • Chirocaine 5 mg/ml - Levobupivacaine
• Drug: EPIDURAL 0mg MORPHINE - 0,2% CHIROCAINE
  Patients will receive intra-operatively a bolus dose of 2 ml of normal saline. Postoperatively, the patients will receive PCEA in a dose of 0,2% levobupivacaine (5ml, lockout interval 10min) combined with a continuous epidural infusion of morphine 0,2 mg/h
  Other Names:

  • Morfina cloridrato 10 mg /ml - Morphine
  • Chirocaine 5 mg/ml - Levobupivacaine
• Drug: EPIDURAL 1 mg MORPHINE - 0,2% CHIROCAINE
  Patients will receive intra-operatively a bolus dose of 1mg of morphine and postoperatively PCEA in a dose of 0,2% levobupivacaine (5ml, lockout interval 10min) combined with a continuous epidural infusion of morphine 0,2 mg/h
  Other Names:

  • Morfina cloridrato 10 mg /ml - Morphine
  • Chirocaine 5 mg/ml - Levobupivacaine
• Drug: EPIDURAL 2 mg MORPHINE-0,2% CHIROCAINE
  Patients will receive a bolus dose of 2 mg of morphine intra-operatively and postoperatively PCEA in a dose of 0,2% levobupivacaine (5ml, lockout interval 10min) combined with a continuous epidural infusion of morphine 0,2 mg/h
  Other Names:

  • Morfina cloridrato 10 mg /ml - Morphine
  • Chirocaine 5 mg/ml - Levobupivacaine

• Active Comparator: GROUP A : 0 mg MORPHINE-0,1% CHIRO
  Group A patients will receive intra-operatively (45 min before the estimated end of the surgery) a bolus dose 2 ml of normal saline. Postoperatively, immediately after extubation patient controlled epidural anesthesia (PCEA) using a continuous epidural infusion of morphine 0,2 mg/h, combined with 0,1% levobupivacaine (5ml, lockout interval 10min) will be administered
  Intervention: Drug: EPIDURAL 0 mgMORPHINE- 0,1%CHIROCAINE
• Active Comparator: GROUP B : 1 mg MORPHINE- 0,1% CHIROCAINE
  Group B patients will receive a bolus dose of 1mg of morphine intra-operatively (45 min before the estimated end of the surgery) and postoperatively the same levobupivacaine and morphine regimen as Group A
  Intervention: Drug: EPIDURAL 1 mg MORPHINE- 0,1% CHIROCAINE
• Active Comparator: GROUP C : 2 mg MORPHINE-0,1% CHIROCAINE
  Group C patients will receive a bolus dose 2 mg of morphine intra-operatively and thereafter the same levobupivacaine and morphine regimen as Group A
  Intervention: Drug: EPIDURAL 2 mg MORPHINE - 0,1%CHIROCAINE
• Active Comparator: GROUP D : 0 mg MORPHINE- 0,2% CHIROCAINE
  Group D patients will receive intra-operatively a bolus dose of 2 ml of normal saline. Postoperatively, the patients will receive PCEA in a dose of 0,2% levobupivacaine (5ml, lockout interval 10min) combined with a continuous epidural infusion of morphine 0,2 mg/h
  Intervention: Drug: EPIDURAL 0mg MORPHINE - 0,2% CHIROCAINE
• Active Comparator: GROUP E : 1 mg MORPHINE-0,2 % CHIROCAINE
  Group E patients will receive intra-operatively a bolus dose of 1mg of morphine intra-operatively and postoperatively the same regimen as Group D.
  Intervention: Drug: EPIDURAL 1 mg MORPHINE - 0,2% CHIROCAINE
• Active Comparator: GROUP F : 2 mg MORPHINE- 0,2% CHIROCAINE
  Group F patients will receive intra-operatively a bolus dose of 2 mg of morphine intra-operatively and thereafter the same regimen as Group D
  Intervention: Drug: EPIDURAL 2 mg MORPHINE-0,2% CHIROCAINE

Inclusion Criteria:

• Body mass index (BMI) > 50
• Age < 50
• Patients written consent to participate in the study

Exclusion Criteria:

• Cardiovascular disease (valvular and ischemic heart disease)
• Patients refusal to participate in the study
• Contraindication to epidural catheter placement (e.g anticoagulation, anti- platelets medication)
• Active psychiatric disease requiring treatment
• Redo surgery