New iv induction anaesthetics

摘要: The history of intravenous (iv) anaesthetic induction agents almost mirrors that the 50 years Canadian Anaesthetists' Society. ~ While other were available before its introduction, thiopentone has been used for slightly more than yr. 2 In fact, Since up until present day, considered as standard against which other/v have to be judged. 3 Over past yr many induce anaesthesia intravenously; however, only a few can "true"/v agents. An ideal /v agent should include following properties.4 1 Predictable, rapid (one arm-to-brain circulation). Lack cardiovascular and respiratory depression. Rapid awakening (recovery). 4 Minimal side-effects. 5 anaphylactic reactions. Intravenous No iv is able meet all these criteria. some withdrawn, such alfathesin; never in Canada, i.e., etomidate; 6 or major extent - methohexitone.7 It interesting look at reasons unavailability above. Alfathesin, mixture two steroids, was widely Europe Canada being withdrawn 'in 1980's. with most since not water soluble and, therefore, required solvent. Alfathesin formulated cremophor EL this formulation led an unacceptably high incidence anaphylactoid 8,9 Etomidate, also insoluble, number undesirable features, pain on injection, involuntary movements, nausea vomiting but causes little 6.~0 However, it released probably will because ability cause adrenal suppression. Another steroidbased agent, minaxolone, appeared promising especially soluble, due problems carcinogenesis rats relatively slow recovery times. ~2 A drugs including benzodiazepines diazepam, midazolam; narcotics fentanyl, morphine ketamine. none really criteria true particularly regard predictability rapidity induction, speed so presentation. Propofol recent introduction propofol (2,6-disoprophylfenol) provided competition agent. R3 again lipid emulsion (10% soya bean oil, 1.2% egg phosphatide 2.25% glycerol) produced same reactions alfathesin. 14 examined under '/v compared primarily thiopentone.