Influence of Cardiopulmonary Bypass, and Sevoflurane or Propofol Anesthesia, on Tissue Oxygen Saturation.

Summary

The purpose of the present study is to assess, by near infrared spectroscopy with INVOS oximeter during vascular occlusion test (VOT), the influence of cardiopulmonary bypass on tissue saturation in thenar muscle.

The secondary aim is to compare the effects of propofol and sevoflurane anaesthesia on tissue saturation.

It is a prospective, randomized, open-label study. Sixty cardiac surgery patients will receive either propofol or sevoflurane anaesthesia. Three-minute VOT will be performed at the following time points: 30 minutes after anaesthesia induction, directly after sternotomy, 20 and 40 minutes after aortic cross-clamping, 20 minutes after aortic cross-clamp removal, and 45 minutes after weaning of cardiopulmonary bypass (CPB).

Group and time effects on tissue saturation will be analysed with ANOVA and post hoc Tukey's test.

Conditions

• NIR Spectroscopy

Interventions

PROCEDURE

NIRS during VOT

Near infrared spectroscopy with INVOS oximeter during vascular occlusion test (VOT) on following timepoints: 1. 30 minutes after anaesthesia induction, 2. directly after the sternotomy, 3. during CPB - 20 minutes after aortic cross-clamping , 4. 40 minutes after aortic cross-clamping, 5. 20 minutes after the release of the aortic cross-clamp, 6. 45 minutes after weaning of CPB.

PROCEDURE

General anaesthesia with propofol use

Premedication: lorazepam 50 μg kg-1, omeprazole 40 mg, and metoprolol 12.5 mg one hour before transport to the operating theatre. Anaesthesia induction: 0.2 mg fentanyl, 0.3 mg/kg, etomidate, and vecuronium bromide 0.1 mg/kg for muscle relaxation, followed by a continuous infusion at the rate of 0.05 mg/kg/h until the sternum closure. Intraoperative analgesia: fentanyl in fractions, up to the total dose of 20-30 μg/kg. Maintenance of anaesthesia in 'Propofol' group will be accomplished using continuous intravenous infusion of propofol 2-4 mg kg/h. Propofol infusion rate will be adjusted according to patient's haemodynamic parameters and the level of anaesthesia, as assessed with Bispectral Index (BIS), with a target range of 40-60.

PROCEDURE

General anaesthesia with sevoflurane use

Premedication: lorazepam 50 μg kg-1, omeprazole 40 mg, and metoprolol 12.5 mg one hour before transport to the operating theatre. Anaesthesia induction: 0.2 mg fentanyl, 0.3 mg/kg, etomidate, and vecuronium bromide 0.1 mg/kg for muscle relaxation, followed by a continuous infusion at the rate of 0.05 mg/kg/h until the sternum closure. Intraoperative analgesia: fentanyl in fractions, up to the total dose of 20-30 μg/kg. Sevoflurane concentration in exhaled gas will be adjusted according to patient's haemodynamic parameters and the level of anaesthesia, as assessed with BIS, with a target range of 40-60.

Sponsors & Collaborators

• Medical University of Gdansk

  lead OTHER

Principal Investigators

• Alexandra Biedrzycka, M.D., Ph.D. · Medical University of Gdańsk, Department of Cardiac Anesthesiology

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2012-03-31

Primary Completion

2013-04-30

Completion

2014-08-31

Countries

• Poland

Study Locations