A. Guttormsen, H. Refsum, P. Ueland
Nov 1, 1994
Citations
0
Influential Citations
60
Citations
Journal
Acta Anaesthesiologica Scandinavica
Abstract
Nitrous oxide (N,O) has been extensively used as an anaesthetic agent since the middle of the nineteenth century. It has been regarded as an ideal drug with few side effects (1). In 1956, Lassen et al. (2) reported that nitrous oxide inhalation for five to six days to control spasms in tetanus patients produced severe bone marrow depression. Twelve years later, Amess and colleagues (3) more directly demonstrated interference with DNA synthesis in bone marrow from patients exposed to nitrous oxide for 24 hours, and they correctly suggested that nitrous oxide may oxidise cobalamin required by methionine synthase (Fig. 1). This mechanism was confirmed by Deacon et al. (4) shortly afterwards. The same year Layzer (5) reported on myeloneuropathy in 15 dentists who had abused nitrous oxide for months to years. Thus, prolonged exposure to nitrous oxide seems to produce haematological and central nervous effects resembling those observed in cobalamin deficiency. This possibility and its biochemical basis have been substantiated by both experimental and clinical studies which are briefly reviewed in this article.