Postoperative Megaloblastic Anemia and Neuromyelopathy Following Nitrous Oxide Exposure

Is the person a health care worker chronically exposed to nitrous oxide?

Does the patient chronically abuse nitrous oxide as a recreational agent?

Has the patient had surgery with nitrous oxide as an anesthetic agent during the past month?

Is the patient at risk for nutritional deficiency based on diet or concurrent disease?

Does the patient show a megaloblastic anemia with increased MCV and hypersegmented neutrophils?

Are serum or urine levels of methylmalonic acid elevated?

Are serum or urine levels of homocysteine elevated?