Background: The 2% formulation of the intravenous anaesthetic agent, propofol (Diprivan), delivers half the amount of lipid compared with the original 1% formulation. This may provide an acceptable alternative for patients who have an impaired ability to metabolise lipids.
Methods: This study was a multicentre, randomised, open comparison of parallel groups. Seventy-three adult patients undergoing elective craniotomy in neurosurgery were randomised to receive either propofol 1% (10 mg/ml) or propofol 2% (20 mg/ml) for induction and maintenance of anaesthesia.
Results: Analysis of induction time (199 s, 1%; 202 s, 2%; p > 0.05) and induction dose (1.13 mg/kg, 1.12 mg/kg; p > 0.05) shows that propofol 1% and propofol 2% are pharmacodynamically equivalent. Both formulations were similar regarding overall administration rates, recovery times, haemodynamic variables and tolerability. Plasma triglyceride levels, were lower in the propofol 2% group compared with the propofol 1% group, and significantly lower (p < 0.05) from 1 to 4 hours after induction.
Conclusions: We conclude that propofol 2% is as effective and as well-tolerated as propofol 1% for anaesthesia and is an acceptable alternative to propofol 1% in patients undergoing elective craniotomy in neurosurgery. The lower lipid load suggests it may be of particular benefit to patients with disorders of lipid metabolism.