<prompt> Which general anaesthetic selectively inhibits excitatory NMDA receptors:ThiopentoneHalothaneDesfluraneKetamine  <response>: Ketamine Intravenous inducing agent. Acts by blocking NMDA receptors. Adverse effects : Hallucinations, delirium and vivid dreams are impoant adverse effects that are seen during recovery from anaesthesia emergence delirium. Has indirect sympathomimetic action blood pressure, hea rate and cardiac output Increases intraocular pressure and intracranial tension Appropriate drug for anesthetizing patients , at high risk of bronchospasm 