Thiopentone in contraindicated in which of the following.

Thiopentone is enzyme inducer so contraindicated in porphyria. Thiopentone is bronchoconstrictor Thiopentone is cardiounstable Thiopentone - Mc, used barbiturates 1. Available as sodium salt and must be dissolved in isotonic sodium chloride (0.9%) or water to prepare solutions of 2.5% 2. Highly alkaline (pH 9) and can be irritating to the tissue of injected extravenously, it does not cause pain on injection. (Methohexitone is only barbiturate causing pain in injections) 3. Induction Dose - 3 to 5 mg/kg (Adults), 5 to 6 mg/kg (Children), 30% decrease dose in old age. Dose calculated according to lean body weight. CNS - It decreases CMRO2 and CBP, as well as ICP. Neuroprotective Decreases EEG activity Anticonvulsant It often produces a subjective feeling of well being on emergence. Metabolism The termination of action of the drug is primarily due to rapid redistribution from centrally highly perfused organs to less perfused organs. Final metabolism - In liver Pharmacodynamics effects:- CNS - Decrease in CMRO2 and CBF, thereby lowering ICP. Improves cerebral perfusion and compliance. Neuroprotective propeies:- Primarily by decreasing oxygen demand. Secondarily by reverse steal on CBF, free - radical scavenging, stabilization of liposomal membranes, as well as excitatory amino- acid receptor blockade. Decrease EEG activity and possess potent anticonvulsant activity. (Methohexital is only barbiturate with epileptogenic effects) CVS - Decreases systemic aerial pressure. Decreases cardiac out put. Decreases peripheral vascular resistance. R.S - Respiratory depression, blunts hypoxiuc hypercepnic drive. Can cause, larygospasm or bronchospasm following induction. Hepatic and Renal - Preexisting hepatic and renal disease result in decreased plasma protein binding of the drug thus enhancing its CNS and cardiovascular depressant propeies. No direct toxicity of liver & kidney.