Anaesthetics volatile general

Volatile lipophilic substances like volatile general anaesthetics, ethyl alcohol, paraldehyde are excreted by the lungs. These volatile substances and certain gases that enter the body through the respiratory tract in the form of aerosol are excreted by this route. 

Mechanism The most pivotal theme to explain the actual mechanism of action of volatile (general) anaesthetics logically and legitimately involves the interaction of the anaestheties with the receptors which critically regulate the performance of the ion-channels, such as K, Cl or with the ion-channel in a direct fashion (e.g., Na ). 

Incubation of the volatile general anaesthetics halothane or methoxyflurane (labelled with C1) with hepatic microsomes. NADPH, and oxygen is accompanied by extensive dechlorination. 

CW agent classes with a direct action on the CNS include nerve agents and incapacitating agents. TIC with central effects include organophosphate and carbamate pesticides and aliphatic hydrocarbons (including volatile general anaesthetics). 

General anaesthetics are administered for many surgical procedures where the patient is likely to undergo a severely painful procedure, and complete unconsciousness and immobility is required for the surgety to be performed. The most commonly used volatile anaesthetics are halothane, isoflurane and sevoflurane. Nitrous oxide is also commonly used, particularly during... 

Inhalation (IH) The administration of volatile gases and vapours, followed by drug absorption in the lungs or nasal mucosa. Examples include general anaesthetics like nitrous oxide, nicotine from the tar droplets in tobacco smoke, cannabinoids from cannabis leaf smoke and various opiates from burning opium resin. 

International Agency for Research on Cancer (IARC). 1976. IARC monographs on the evaluation of the carcinogenic risk of chemicals to man cadmium, nickel, some epoxides, miscellaneous industrial chemicals and general considerations on volatile anaesthetics. Volume 11. World Health Organization, IARC, Lyon, France. 306 pp. 

Atropine and other drugs from this group has been a standard preoperative adjuvant therapy in general anesthesia since they inhibit the reflex increase of bronchial secretion due to mechanical irritation (intubation) and volatile anaesthetics. 

Cadmium, Nickel, Some Epoxides, Miscellaneous Industrial Chemicals and General Considerations on Volatile Anaesthetics... 

LEVODOPA ANAESTHETICS -GENERAL-VOLATILE AGENTS Possible risk of arrhythmias Uncertain Monitor EGC and BP closely. Consider using intravenous agents for maintenance of anaesthesia... 

Prior to 1956, the most common anaesthetics included diethyl ether and chloroethane, with the associated risks. Fluothane (ICI) was the first widely used fluorine-containing volatile anaesthetic [80], and such was its success that it has been estimated that 70-80% of all anaesthesias carried out in 1980 were performed using this substance. However, Isoflurane , Sevoflurane and Desflurane are now coirunercially available alternatives in the general quest for less readily metabolised systems and faster recovery times of the patients (Figure 1.2). 

Alcohol acts on the central nervous system in a manner broadly similar to volatile anaesthetics, exerting on cells a generally depressant effect that is probably mediated through particular membrane ion channels and receptors. Alcohol enhances (inhibitory) GABA-stimulated flux of chloride through receptorgated membrane ion channels, a receptor subtype... 

Mechanism Probably at equilibrium, the prevailing concentration of a volatile anaesthetic in the alveoli is equal to that in the brain and eonsequently this partieular eoneentration in the brain that very intimately exhibits the eoneentration at the site responsible for the anaesthetie aetivities. Therefore, the MAC of a volatile anaesthetic is most frequently employed as a reliable yardstick to ascertain the exact potency of an individual general anaesthetic agent. Table-1 depicts the MAC values of several gaseous and volatile anaesthetics commonly put into practice nowadays. 

Interestingly, when these general (volatile) anaesthetics are employed in combination, the MACs for the Inhaled Anaesthetics are Additive. 

General biological depressants (hypnotics, general anaesthetics, and volatile insecticides). 611... 

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