[Clinical use of propofol in neuroanesthesia]

Abstract

Since Althesin was withdrawn from the market, and since Ledingham's report on the inhibitory effect of etomidate on cortisol secretion, anaesthesia in intracranial surgery has lacked an intravenous agent with a pharmacokinetic-dynamic profile making it a suitable alternative to the classic thiopental-isoflurane sequence. Propofol has been used experimentally in neuroanaesthesia for 4 years, and is now ready to be used on a routine basis in neuroanaesthesia. An induction dose of propofol decreases cerebral blood flow (CBF), cerebral metabolic rate for oxygen (CMR02), and intracranial pressure (ICP). Mean arterial pressure (MAP) is only moderately decreased if propofol is given as a mini-infusion instead of being given on a mg/kg basis. The intraoperative dosage is low (50-100 micrograms.kg-1 x min-1) due to the fact that intracerebral surgery is not painful. Recovery can thus be rapid. Propofol is used with the same agents or manoeuvres as those used with the thiopental-isoflurane sequence, i.e. lidocaine, fentanyl, esmolol, mannitol, steroids, hyperventilation and lumbar drainage in order to obtain the most relaxed brain and reduce the mechanical pressure exerted on the brain. Propofol can be used for all intracranial pathologies with may be one exception, when a cerebral aneurysm has to be clipped and vasospasm is present.