Sevoflurane Versus Intravenous Anaesthetic Agents in Morbid Obese Patients

Propofol Versus Sevoflurane as Sole Anesthetic Agent in Gastric By-Pass Surgery for Morbid Obesity: A Prospective Randomized Clinical Trial

The objective of this prospective randomized clinical study was to compare anesthesia, in morbidly obese patents (BMI >50) who underwent BPD-RYGBP with either sevoflurane or propofol with remifentanyl.

This is a prospective double blind randomized controlled trial. The patients will be assigned to one of 4 groups (gr): (1) SEVO group, guided by a target end tidal concentration 1 - 2 MAC and modified according to the haemodynamics (BP, HR) of the patients using a bolus inhalation (4 MAC), (2) SEVO-BIS group, using SEVO to a target BIS of 40 - 50, (3) PROPO-REMI and (4) PROPO-REMI-BIS groups accordingly. In groups 1 and 2, anaesthesia will be induced with IV PROPO (2 mg/kg TW [TW = ideal body weight, IBW + 0.4 * difference to the excess weight]), REMI (1 μg/kg IBW) and succinylcholine (1mg/kg IBW). In groups 3, 4 anaesthesia will be induced with a continuous IV PROPO infusion (21mg/kg TW/h for 5 min, 12 mg/kg TW/h for 10 min and then 6 mg/kg TW/h), followed by an IV bolus of REMI and succinylcholine as above. Every rise of BP or HR > 15% of baseline will be followed by a bolus SEVO inhalation in grs 1 and 2 or REMI bolus IV (1 μg/kg IBW) and increase in the continuous infusion rate of REMI from 0.1 to 1.0 μg/kg/min in groups 3 and 4. An epidural catheter will be placed prior to induction for postoperative analgesia only. Intraoperative BP and HR, anaesthetic consumption, recovery scores (Aldrete, Chung, White) and anaesthesia cost will be evaluated.

Inclusion Criteria:

• Age 18-50 yrs
• BMI>50 kg/m2
• Written consent for the participation in the study

Exclusion Criteria:

• History of significant cardiac disease, (aortic stenosis, angina, CHF or previous cardiac or intrathoracic operations)
• Significant renal dysfunction (serum creatinine>1.8 mg/dl)
• Significant liver dysfunction (evidenced by abnormal LFTs)
• History of hyper or hypothyroidism
• History of psychiatric or neurologic disorders
• Recall during general anesthesia
• Substance abuse (alcohol or other drugs)
• Counter-indications of placement of thoracic epidural catheter( previous spine surgery or coagulation abnormalities )
• Refusal to participate in the study