Biological Diagnosis and Monitoring of Chronic Nitrous Oxide Abuse

Condition(s) studied

Investigational drug(s) / intervention(s)

blood collection: Biological analyses in the framework of care with conservation of blood samples

Study summary

There is a toxicity linked to the chronic use of nitrous oxide, leading to neurological disorders such as combined sclerosis of the spinal cord. One thus frequently observes patients presenting disorders of walking or paresthesias, of more or less resolving evolution being able to go until the need for using a wheelchair and more recently cases of thrombosis were reported Serum or urine N2O assays are rarely performed routinely, because they do not allow to ensure a real exposure due to the very short half-life of this gas in the body. Thus, other biological monitoring markers are mentioned in the literature, such as vitamin B12 or homocysteine. Unfortunately, there are still no recommendations for biological monitoring of nitrous oxide consumption. Moreover, underlying mechanisms leading to clinical outcomes remains misunderstood.

Eligibility

Primary outcome measure(s)

• Blood markers related to nitrous oxide consumption — through study completion an average of 1 year
  Biomarkers of cobalamin metabolism, methionine cycle and oxidative stress

Trial sites (8)

More University Hospital, Lille trials in France