Sevoflurane Versus Intravenous Anaesthetic Agents in Morbid Obese Patients

University of Patras

Status and phase: Unknown; Phase 3; Phase 2

Conditions: Morbid Obesity

Treatments: Drug: Propofol- Remifentanyl; Drug: Sevoflurane; Drug: Propofol, Remifentanyl

Study type: Interventional

Funder types: Other

Identifiers

NCT01279499

sevoflurane-propofol-obesity

Details and patient eligibility

About

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.

Full description

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.

Enrollment: 100 estimated patients

Sex: All

Ages: 18 to 50 years old

Volunteers: No Healthy Volunteers

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

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Triple Blind

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100 participants in 4 patient groups

SEVO group

Active Comparator group

Description:

Anaesthesia will be induced with IV Propofol (2 mg/kg TW \[TW = ideal body weight, IBW + 0.4 \* difference to the excess weight\]), Remifentanyl (1 μg/kg IBW) and succinylcholine (1mg/kg IBW).Intraoperatively Sevoflurane will be guided by a target end tidal concentration 1 - 2 MAC .Every rise of BP or HR \> 15% of baseline will be followed by a bolus SEVO inhalation 8% MAC for 2 minutes.If the positive sympathetic response persists, then Nifedipine 10 mg will be administered sublingual, if HR \< 70/ minute, and Diltiazem 10-20 mg IV will be administered if HR \> 70/ minute, followed by esmolol administration if response to diltiazem is unsatisfactory. The duration and frequency of positive sympathetic stress responses that required pharmacologic intervention will be recorded.

Treatment:

Drug: Sevoflurane

Drug: Sevoflurane

SEVO-BIS group

Active Comparator group

Description:

Anaesthesia will be induced with IV Propofol (2 mg/kg TW \[TW = ideal body weight, IBW + 0.4 \* difference to the excess weight\]), Remifentanyl (1 μg/kg IBW) and succinylcholine (1mg/kg IBW).Intraoperatively Sevoflurane will be guided by a target BIS of 40 - 50 .Every rise of BP or HR \> 15% of baseline will be followed by a bolus SEVO inhalation 8% MAC for 2 minutes. If the positive sympathetic response persists, then Nifedipine 10 mg will be administered sublingual, if HR \< 70/ minute, and Diltiazem 10-20 mg IV will be administered if HR \> 70/ minute, followed by esmolol administration if response to diltiazem is unsatisfactory. The duration and frequency of positive sympathetic stress responses that required pharmacologic intervention will be recorded.

Treatment:

Drug: Sevoflurane

Drug: Sevoflurane

Propo- Remi group

Active Comparator group

Description:

General Anaesthesia (GA) will be induced with a continuous IV Propofol (P) infusion (21mg/kg TBW for 5 min, 12 mg/kg TBW for 10 min and then 6 mg/kg TBW), followed by an IV bolus of Remifentanyl (R, 1 μg/kg IBW) and succinylcholine (1mg/kg IBW). GA will be maintained with continuous intravenous administration of P at 150-300mcg/kg/min (doses based on ideal body weight). Every rise of BP or HR \> 15% of baseline will be followed by a R bolus IV (1 μg/kg IBW) and increase in the continuous infusion rate of R to 1.0 μg/kg/min . If HR \< 70/ minute, and Diltiazem 10-20 mg IV will be administered if HR \> 70/ minute, followed by esmolol administration if response to diltiazem is unsatisfactory. The duration and frequency of stress responses that required intervention is recorded.

Treatment:

Drug: Propofol- Remifentanyl

Propo-Remi-BIS group

Active Comparator group

Description:

General Anaesthesia (GA) will be induced with a continuous IV Propofol (P) infusion (21mg/kg TBW for 5 min, 12 mg/kg TBW for 10 min and then 6 mg/kg TBW), followed by an IV bolus of Remifentanyl (R, 1 μg/kg IBW) and succinylcholine (1mg/kg IBW). GA will be maintained with continuous intravenous administration of P at 150-300mcg/kg/min (IBW). The depth of anesthesia will be adjusted to accomplish a BIS score 40 -50. If BP or HR is \> 15% of baseline will a bolus of R IV (1 μg/kg IBW) will be given and an the infusion rate of R will be increased to 1.0 μg/kg/min . If this response persists and HR \< 70/ min, Nifedipine 10 mg will be given s.l. and if HR \> 70/ min Diltiazem 10-20 mg IV will be given, followed by esmolol infusion if no response is observed.

Treatment:

Drug: Propofol, Remifentanyl