This study investigated the stimulative or sedative effects of inhaling fragrant essential oils (EOs) by using a forced swimming test (FST) with mice. This behavioral test is commonly used to measure the effects of antidepressant drugs. The inhalation by mice of EOs, such as ginger oil (p. Cedrol: A Useuful Sesquiterpene Alcohol Found in the Essential Oil Cedrol, which is one of fragrance components, is a sesquiterpene alcohol found in the essential oil of conifers (cedar oil). Cedrol is reported to have useful effects on autonomic and central nervous system, so that scientific research will be further expected.
Bottles of, and, the common fluorinated anaesthetics used in clinical practice. These agents are colour-coded for safety purposes. Note the special fitting for desflurane, which at.An inhalational anesthetic is a chemical compound possessing properties that can be delivered via inhalation. They are administered through a face mask, or connected to an and an. Agents of significant contemporary clinical interest include anaesthetic agents such as, and, as well as certain anaesthetic gases such as. Contents.List of inhalational anaesthetic agents Currently-used agents.Previously-used agents Although some of these are still used in clinical practice and in research, the following anaesthetic agents are primarily of historical interest in:.
(still widely used in the and is on the ). (still used currently as an ).Never-marketed agents.Volatile anaesthetics Volatile anaesthetic agents share the property of being liquid at room temperature, but evaporating easily for administration by inhalation. All of these agents share the property of being quite (i.e., as liquids, they are not freely with water, and as gases they dissolve in oils better than in water).
The ideal volatile anaesthetic agent offers smooth and reliable induction and maintenance of with minimal effects on other systems. In addition it is odourless or pleasant to inhale; safe for all ages and in; not metabolised; rapid in onset and offset; potent; and safe for exposure to staff. It is also cheap to manufacture; easy to transport and store, with a long; easy to administer and monitor with existing equipment; stable to, and; non-flammable and environmentally safe. None of the agents currently in use are ideal, although many have some of the desirable characteristics. For example, sevoflurane is pleasant to inhale and is rapid in onset and offset. It is also safe for all ages.
However, it is expensive (approximately 3 to 5 times more expensive than isoflurane), and approximately half as potent as isoflurane.Gases Other or vapors which produce general anaesthesia by inhalation include nitrous oxide, cyclopropane and xenon. These are stored in and administered using, rather than vaporisers. Cyclopropane is and is no longer used for safety reasons, although otherwise it was found to be an excellent anaesthetic. Xenon is odourless and rapid in onset, but is expensive and requires specialized equipment to administer and monitor. Nitrous oxide, even at 80% concentration, does not quite produce surgical level anaesthesia in most persons at, so it must be used as an adjunct anaesthetic, along with other agents.Hyperbaric anaesthesia Under conditions ( above normal ), other gases such as, and such as, and xenon become anaesthetics. When inhaled at high (more than about 4 bar, encountered at depths below about 30 metres in ), nitrogen begins to act as an anaesthetic agent, causing.
However, the (MAC) for nitrogen is not achieved until pressures of about 20 to 30 atm (bar) are attained. Argon is slightly more than twice as anaesthetic as nitrogen per unit of partial pressure (see ). Xenon however is a usable anaesthetic at 80% concentration and normal atmospheric pressure. Neurological theories of action.
Main article:The full mechanism of action of volatile anaesthetic agents is unknown and has been the subject of intense debate. 'Anesthetics have been used for 160 years, and how they work is one of the great mysteries of neuroscience,' says anaesthesiologist James Sonner of the University of California, San Francisco. Anaesthesia research 'has been for a long time a science of untestable hypotheses,' notes Neil L. Harrison of Cornell University.'
Most of the injectable anesthetics appear to act on a single molecular target,' says Sonner. 'It looks like inhaled anesthetics act on multiple molecular targets. That makes it a more difficult problem to pick apart.' The possibility of anaesthesia by the inert gas argon in particular (even at 10 to 15 bar) suggests that the mechanism of action of volatile anaesthetics is an effect best described by, and not a action. However, the agent may bind to a receptor with a weak interaction. A physical interaction such as swelling of nerve cell membranes from gas solution in the lipid bilayer may be operative. Notably, the gases hydrogen, helium, and neon have not been found to have anaesthetic properties at any pressure.
Helium at high pressures produces nervous irritation ('anti-anaesthesia'), suggesting that the anaesthetic mechanism(s) may be operated in reverse by this gas (i.e., nerve membrane compression). Also, some halogenated ethers (such as ) also possess this 'anti-anaesthetic' effect, providing further evidence for this theory.History The concept was first used by, such as, and in the 11th century. They used a sponge soaked with narcotic drugs and placed it on a patient's face. These Arabic physicians were the first to use an anaesthetic sponge.developed an inhalational anaesthetic in 1540. He used sweet oil of vitriol (prepared by Valerius Cordus and named Aether by Frobenius): used to feed fowl: “it was taken even by chickens and they fall asleep from it for a while but awaken later without harm”.
Subsequently, about 40 years later, in 1581, Giambattista Delia Porta demonstrated the use of ether on humans although it was not employed for any type of surgical anesthesia. See also.
a mixture of, chloroform and diethyl ether.References.
The use of aerosolized furosemide has been increasing throughout Mexico, primarily because of its mechanism and site of action as well as its local and systemic effect. We hypothesize that its effect on the respiratory system is totally independent from its diuretic activity and that it is primarily caused by its interaction with the chlorine channels. Furthermore, there is also evidence that furosemide induces prostaglandin synthesis, blocks the sodium-calcium pump, producing relaxation of the smooth muscle that narrows the airway and causes reduced nerve responsiveness to the Neurokinin A produced in acute asthma attacks.