Nitrous oxide effects

Users should also avoid inhaling directly from a nitrous oxide aerosol can. Some users have died as a consequence of freezing the throat area because the heat is absorbed as the gas expands. Freon, a similar molecule used as an aerosol propellant, does not have nitrous oxide effects. 

Fournier L, Major D. Nitrous oxide effects on PO2 measurements in the operating room shift of the oxyhaemoglobin curve. Can Anaesth Soc J 1982 29 498. 

Gate oxide dielectrics are a cmcial element in the down-scaling of n- and -channel metal-oxide semiconductor field-effect transistors (MOSEETs) in CMOS technology. Ultrathin dielectric films are required, and the 12.0-nm thick layers are expected to shrink to 6.0 nm by the year 2000 (2). Gate dielectrics have been made by growing thermal oxides, whereas development has turned to the use of oxide/nitride/oxide (ONO) sandwich stmctures, or to oxynitrides, SiO N. Oxynitrides are formed by growing thermal oxides in the presence of a nitrogen source such as ammonia or nitrous oxide, N2O. Oxidation and nitridation are also performed in rapid thermal processors (RTP), which reduce the temperature exposure of a substrate. 

Alkaline solutions of mononitroparaffins undergo many different reactions when stored for long periods, acidified, or heated. Acidification of solutions of mononitro salts is best effected slowly at 0°C or lower with weak acids or buffered acidic mixtures, such as acetic acid—urea, carbon dioxide, or hydroxyl ammonium chloride. If mineral acids are used under mild conditions, eg, dilute HCl at 0°C, decomposition yields a carbonyl compound and nitrous oxide (Nef reaction). 

Safety provisions have proven highly effective. The nuclear power industry in the Western world, ie, outside of the former Soviet Union, has made a significant contribution of electricity generation, while surpassing the safety record of any other principal industry. In addition, the environmental record has been outstanding. Nuclear power plants produce no combustion products such as sulfuric and nitrous oxides or carbon dioxide (qv), which are... 

Effect of Nitric Oxide on Ozone Depletion. Nitrous oxide is injected into the atmosphere from natural sources on earth about 10% is converted to nitric oxide (N20 + 0( D) — 2 NO), which in turn can catalyze the destmction of ozone (11,32,75). The two main cycles are 1 and 2. Rate constant data are given in Reference 11. 

Nitrous oxide produces respiratory depression (38,39). It has been shown to produce a direct myocardial depressant effect in dogs (40) and in humans breathing a 40% N2O/60% oxygen mixture (41) however, this may be offset by the activation of the sympathetic nervous system (42). The combination of nitrous oxide and opioids can produce decreases in myocardial contractiHty, heart rate, and blood pressure (43). 

There appear also to be toxic effects. In animals, nitrous oxide has been shown to inactivate methionine synthetase which prevents the conversion of deoxyuridine to thymidine and thus has the potential for inducing megaloblastic anemia, leukopenia, and teratogenicity (44—46). A variety of epidemiologic surveys suggest positive correlations between exposure to nitrous oxide and spontaneous abortion in dental assistants (47). 

Assuming the randomness factor is about the same, the gas with the larger heat effect (favoring dissolving) should have the higher solubility. The measured solubilities at one atmosphere pressure and 20°C of oxygen and nitrous oxide in water are, respectively, 02, 1.4 X 10-3 mole/liter and N20, 27 X 10-3 mole/liter, consistent with our prediction.. 

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. 

Efforts to identify the specific compounds responsible for the psychotropic effects of volatile solvents are complicated by the fact that many of these products contain more than one potentially psychoactive ingredient. Another factor obscuring the identity of the psychoactive ingredients of these agents is that patients addicted to these compounds frequendy seek the effects not of the product s primary ingredient but of a secondary ingredient such as the propellant gas (e.g., nitrous oxide). To date, the best-studied psychoactive compounds identified in volatile solvents include toluene, 1,1,1-trichloroethane, and trichloroethylene. However, other less well studied compounds, such as benzene, acetone, and methanol, also appear to have significant psychoactive effects. 

On the other hand, clinical and laboratory studies in humans have demonstrated the development of tolerance to the amnestic and analgesic effects of nitrous oxide and isoflurane (see Arnold et al. 1993 Avramov et al. 1990 Rupreht et al. 1985 Whitwam et al. 1976) and, in the case of ether or chloroform, to its reinforcing effects (Krenz et al. 2003). No studies have shown the development of tolerance to the reinforcing effects of nitrous oxide. 

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). 

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