Nitrous oxide inhalational

There are few reports on the effects of nitrous oxide on dopaminergic neurotransmission. A study in mice showed that nitrous oxide inhalation produced a significant increase in locomotor activity that was antagonized in a dose-dependent fashion by the dopamine synthesis inhibitor a-methyl-/)-tyrosine (Hynes and Berkowitz 1983). Moreover, administration of the D2 antagonist haloperidol also reduced the locomotor activity induced by nitrous oxide (Hynes and Berkowitz 1983). These results suggest that excitatory effects induced by nitrous oxide may be also mediated by dopaminergic neurotransmission. However, other studies have reported that exposure to nitrous oxide resulted in decreased dopamine release by neurons in the striatum (Balon et al. 2002 Turle et al. 1998). 

G7. Green, C. D., and Eastwood, W., Effects of nitrous oxide inhalation on hemopoiesis in rats. Anesthesiology, 24, 341-345 (1963). 

Although airway conductance may be reduced by nitrous oxide, respiratory depression is unlikely after short-term exposure (8). The respiratory safety of nitrous oxide inhalation in children has been confirmed (9). 

Nitrous oxide inhalation can give false PO2 measurement... 

The main complications associated with nitrous oxide inhalation occur as a result of hypoxia. Prolonged administration may also be harmful. Nitrous oxide is rapidly absorbed on inhalation. 

FIGURE 82 Propofol, like thiopental, induces anesthesia rapidly, but the maintenance of anesthesia may require nitrous oxide, inhalational anesthetics, and opioids. Propofol does not impair hepatic or renal functions. 

Gyulai FE, Firestone LL, Mintun MA et al. In vivo imaging of human limbic responses to nitrous oxide inhalation. Int J Addict 1983 ... 

Two methods of anaesthesia are currently in use, the application of inhaled gaseous or volatile anaesthetics such as halothane, sevoflurane and isoflurane to maintain a level of anaesthesia. Older compounds in this category include nitrous oxide and chloroform. 

The anesthesiologist selects the anesthetic drug that will produce safe anesthesia, analgesia (absence of pain), and in some surgeries, effective skeletal muscle relaxation. General anesthesia is most commonly achieved when the anesthetic vapors are inhaled or administered intravenously (IV). Volatile liquid anesthetics produce anesthesia when their vapors are inhaled. Volatile liquids are liquids that evaporate on exposure to air. Examples of volatile liquids include halothane, desflurane, and enflurane. Gas anesthetics are combined with oxygen and administered by inhalation. Examples of gas anesthetics are nitrous oxide and cyclopropane. 

Halothane (Fluothane) is a volatile liquid given by inhalation for induction and maintenance of anesthesia Induction and recovery from anesthesia are rapid, and the depth of anesthesia can be rapidly altered. Halothane does not irritate the respiratory tract, and an increase in tracheobronchial secretions usually does not occur. Halothane produces moderate muscle relaxation, but skeletal muscle relaxants may be used in certain types of surgeries. This anesthetic may be given with a mixture of nitrous oxide and oxygen. 

Nonetheless, it was not until 1793 that the English scientist and clergyman Joseph Priestley discovered the first modern inhalant compound, the anesthetic gas nitrous oxide. This gas was widely used for recreational purposes by the English aristocracy in private parties, and traveling charlatans expanded... 

Nitrous oxide is rapidly absorbed through inhalation, and it is distributed predominantly in blood with a blood/gas partition coefficient of 0.5 (Sten-qvist 1994). It is rapidly eliminated through the lungs, with small amounts being eliminated through the skin (Stenqvist 1994). 

Dohrn CS, Lichtor JL, Finn RS, et al Subjective and psychomotor effects of nitrous oxide in healthy volunteers. Behav Pharmacol 3 19-30, 1992 Dohrn CS, Lichtor JL, Coalson DW, et al Reinforcing effects of extended inhalation of nitrous oxide in humans. Drug Alcohol Depend 31 263-280, 1993 Evans AC, Raistrick D Phenomenology of intoxication with toluene-based adhesives and butane gas. Br J Psychiatry 130 769-773, 1987 Evans EB, Balster RL CNS depressant effects of volatile organic solvents. Neurosci Biobehav Rev 13 233—241, 1991... 

Baden JM, Kelley M, Mazze Rl, et al. 1979. Mutagenicity of inhalation anaesthetics Trichloroethylene, divinyl ether, nitrous oxide, and cyclopropane. Br J Anaesth 51 417-421. 

A man habitually enjoyed the euphoric effects of inhaling whiffs of nitrous oxide in seclusion, and kept a cylinder of the gas in his sedan for that purpose. He decided to spray the faded car seats with an aerosol can of vinyl dressing (propanc/butanc propellant) with the windows closed. Then he had a whiff of gas from the briefly opened cylinder, and settled back to enjoy the euphoria and a cigarette. He was lucky to survive the resulting explosion of the fuel/oxidant mixture in a closed vessel [2],... 

The distribution of anesthetic throughout the entire body may be viewed as an equilibration process (Fig. 7.1.13), with tissues characterized by high blood flows reaching equilibration faster than muscle and fatJ4 Nevertheless, an anesthetic that is excessively soluble in blood will not partition substantially into brain and other tissues. The anesthetic properties of nitrous oxide and diethyl ether have been known since the 1840s. Zeneca Pharmaceuticals introduced the first modem inhalation anesthetic fluothane in 1957. Methoxyfluorane followed in 1960, enflurane 1973, isoflurane 1981, desflurane by Anaquest (Liberty Comer, NJ) in 1992, and sevoflurane by Abbott Laboratories in 1995J6 ... 

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. 

Organic solvents inhaled by abusers include gasoline, glue, aerosols, amyl nitrite, butyl nitrite, typewriter correction fluid, lighter fluid, cleaning fluids, paint products, nail polish remover, waxes, and varnishes. Chemicals in these products include nitrous oxide, toluene, benzene, methanol, methylene chloride, acetone, methyl ethyl ketone, methyl butyl ketone, trichloroethylene, and trichloroethane. 

Diethyl ether was the inhalation anesthetic of choice during my childhood. Happily, 1 had rather little need of it. Ether was replaced years ago by a family of superior inhaled general anesthetics, most of which are ethane derivatives. The notable exception is another very simple molecule, nitrous oxide, N2O, frequently known as laughing gas. N2O has been around for a long time and was once a party drug. ... 

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