Total intravenous anaesthesia using propofol, gamma-hydroxybutyrate or midazolam in combination with sufentanil for patients undergoing coronary artery bypass surgery

Abstract

Total intravenous anaesthesia (TIVA) using propofol, gamma-hydroxybutyrate (GHB) or midazolam in combination with sufentanil was investigated in 45 patients undergoing coronary artery bypass grafting (CABG). Anaesthesia was induced with sufentanil, etomidate and pancuronium. After endotracheal intubation, anaesthesia was continued with sufentanil (2 μg kg⁻¹ h⁻¹) for all patients. Patients were randomized to receive supplementary propofol (2 mg kg⁻¹ h⁻¹, n = 15), gamma-hydroxybutyrate (20 mg kg⁻¹ h⁻¹, n = 15) or midazolam (0.06 mg kg⁻¹ h⁻¹, n = 15). Haemodynamic measurements were performed after induction and at various times in the pre-bypass period. In the propofol group, a significant decrease in heart rate (HR 12%±3%), cardiac index (CI 23%±4%), mean arterial pressure (MAP 16%±3%) and left ventricular stroke work index (LVSWI 17%±4%) occurred until sternotomy was performed. With the exception of cardiac index, both midazolam and gamma-hydroxybutyrate produced similar haemodynamic effects: cardiac index was temporarily decreased (19%±4%) by midazolam and remained unchanged after gamma-hydroxybutyrate. In both groups, sternotomy was followed by temporary hypertension, associated with a significant rise in systemic vascular resistance. No electrocardiographical signs of ischaemia were observed in any patient. In the case of propofol and midazolam, gamma-hydroxybutyrate showed adequate haemodynamic stability especially after induction of anaesthesia and may also be a suitable agent for total intravenous anaesthesia in patients with coronary artery disease. However, during sternotomy, supplementary administration of opioids was required.