BACKGROUND The effect of nitrous oxide on ischemic neuronal damage was quantitatively evaluated by use of logistic regression curves. METHODS Seventy-two gerbils were anesthetized with 1% halothane and randomly assigned to receive 70% nitrous oxide or 70% nitrogen. Forebrain ischemia was performed for 3, 5, or 7 min, and direct-current potential in the hippocampal CA1 region was recorded. His...

Atmospheric nitrous oxide concentrations have been increasing since the industrial revolution and currently account for 6% of total anthropogenic radiative forcing. Microbial production in soils is the dominant nitrous oxide source; this has increased with increasing use of nitrogen fertilizers. However, fertilizer use alone cannot account for the historical trends of atmospheric concentrations...

We have investigated whether nitrous oxide antagonizes or augments the CNS stimulant action of laudanosine in mice by comparing the mean convulsive doses (CD50 (SE] of a control group and those following pretreatment with 65% nitrous oxide in oxygen for 20 and 180 min. Nitrous oxide significantly increased CD50 from 46.8 (1.4) mg kg-1 of control to 57.3 (1.3) mg kg-1 at 20 min and 53.5 (1.7) mg...

Dentists, as well as other dental personnel are constantly exposed to a number of specific occupational hazards. These cause the appearance of various ailments, specific to the profession, which develop and intensify with years. In many cases they result in diseases and disease complexes, some of which are regarded as occupational illnesses. Relying on relevant literature, the present paper dis...

ALTHOUGH nitrous oxide is safe when administered by anesthesiologists, misuse may result in brain damage either via asphyxia or via direct effects resulting in vacuole formation in cingulate and retrosplenial cortices under normoxic conditions. The direct toxic effects of nitrous oxide raise the possibility that nitrous oxide toxicity results from excitatory effects of the drug. To determine ho...

We have investigated, in volunteers, the effect of inhaling 50% nitrous oxide in oxygen on subsequent oxygenation. Subjects breathed either 50% nitrous oxide in oxygen or 50% nitrogen in oxygen during hyperventilation and normal ventilation. Arterial oxygen saturation and end-expired oxygen concentrations were lower after 50% nitrous oxide in oxygen than after the other mixture with both patter...

Background. Funicular myelosis is a known consequence of exposure to nitrous oxide. Nevertheless, there are only a few clinical trials assessing its long-term effects and there is no literature about the role of nutritional vitamin B12 supplementation in the context of nitrous oxide abuse. Case Descriptions. We diagnosed funicular myelosis in a young butcher, who consumed high amounts of meat r...

We studied 88 healthy, ASA I patients (aged 20-45 yr), to determine if nitrous oxide affects thiopentone requirements for achieving 50% probability of no movement in response to verbal commands (CP,50). Patients were allocated randomly to one of four nitrous oxide concentration groups (0%, 20%, 40% and 60%). Patients in each group were also allocated randomly to receive predetermined target pla...

Administration of nitrous oxide is useful for providing sedation and analgesia. The therapeutic range for nitrous oxide is 20-30%. Several oxygen treatment devices have been used for administering nitrous oxide, but little is known about the concentrations of nitrous oxide and oxygen delivered to the trachea. We have studied this, using an analogue lung model, with several oxygen therapy device...

The effects of nitrous oxide alone and combination of nitrous oxide and fentanyl on spinal reflexes were studied in cats with transected spinal cord at the thoracic level. Nitrous oxide 33, 50 and 75% in oxygen depressed the amplitude of monosynaptic reflexes in a dose-dependent manner, but exerted little effect on polysynaptic reflexes. The addition of fentanyl 2.5 microgram kg-1 during the ad...