Intravenous anaesthetic drug that doesn't induce cerebral metabolism:

Ref: Miller Textbook of Anaesthesia. 6th edition.Explanation:ThiopentonePH-10.5Ultra short acting barbiturateThiopentone has an half-life of 11-26 hour.Commonly in the induction of general anesthesia. Its use has been largely replaced with that of propofol.Following intravenous injection the drug rapidly reaches the brain and causes unconsciousness within 15 seconds.At one minute, the drug attains a peak concentration of about 60% of the total dose in the brain.Thereafter, the drug distributes to the rest of the body and in about 5-10 minutes the concentration is low enough in the brain such that consciousness returns.Causes hypotension and tachycardiaPrecipitates acute intermittantporphyria, hence contraindicated in PorphyriasAccidental Intra-arterial injection causes severe pain & gangrene.Can trigger Malignant HyperthermiaCerebral oxygen consumption (CMO), cerebral metabolic rate (CMR) and intracranial tension (ICT) are decreased. So, it is the intravenous agent of choice for cerebral protection.