In: Anesthesia3 Oct 2009
Since its first use in 1844, nitrous oxide (N20) has been considered one of the safest anesthetics and is still widely used in clinical practice. However, a number of studies have associated chronic exposure to N20 with certain adverse effects, such as leukopenia, embryo toxicity, and fetal death. Exposure to N20 in operating rooms appears to result from passive inhalation of the gas. Epidemiologic investigations conducted in the early 1970s suggested that significant occupational hazards to female personnel (birth defects and abortions) were associated with long-term employment in operating rooms using NjpO. In addition, exposure to N20 in facilities where the gas is not scavenged may also result in a significant decrease in fertility in women. Supporting evidence from animal studies indicates that subclinical concentrations of N20 over time result in fertility problems in both male and female rats as well as decreased litter size and weight of the Fx generation.
The mechanism by which N20 might interfere with reproductive function in women is unclear. Some evidence indicates that rats exposed to chronic N20 have a dysfunctional hypothalamic-hypophyseal-gonadal axis. Several reports suggest that N20 may act via the endogenous opioid neural system to influence gonadotropin-releasing hormone (GnRH) neurons.Exposure to N20 also results in alterations in GnRH levels in the diencephalon, implying a disruption of GnRH-secreting neuronal cell function. As yet, there are no reports indicating direct effects of N20 on GnRH-secreting neurons. The aim of this study is to evaluate the direct actions of N20 on various cellular events in cultured GnRH-producing (GT1-7) cells.
cheap levitra professional
Blog invites submissions of review articles, reports on clinical techniques, case reports, conference summaries, and articles of opinion pertinent to the control of pain and anxiety in dentistry.