Korean J Anesthesiol.  2005 Jan;48(1):85-91. 10.4097/kjae.2005.48.1.85.

Respiratory Complications Due to Nitrous Oxide Impurities Six cases

• Han MA
• Kim MC
• Cho KH
• Kim CS

• KMID: 2091960
• DOI: http://doi.org/10.4097/kjae.2005.48.1.85

Abstract

The impurities potentially contained in nitrous oxide cylinders include NO, NO2, CO and NH3. The consequences of inahaling NO and NO2 are reflex breathing inhibition with laryngospasm and the rapid onset of intense cyanosis due to altered pulmonary gas exchange and methaemoglobinemia. Pulmonary edema may occur in the acute stage. Chronic chemical pneumonitis may follow with resultant pulmonary fibrosis and the respiratory and metabolic acidosis may also occur. Hypotension may be marked and results from the effects of nitrate and nitrite ions on vascular smooth muscle. Since certain clinical features provide clues that allow practicing anesthetists to recognize the toxicities of higher nitrogen oxides, six of our cases will be described in detail, whereas the remaining cases will be only commented. We examined a N2O cylinder at the National Metrology Institute, its NOX concentration was 2359 ppm. Another two cylinders were also abnormal with NOX concentrations of 547 ppm and 180 ppm. We recommend that medical gases be subjected to quality control on a national basis.

Keyword

nitous oxide impurities; pulmonary edema

MeSH Terms

Acidosis
Cyanosis
Gases
Hypotension
Ions
Laryngismus
Muscle, Smooth, Vascular
Nitrogen Oxides
Nitrous Oxide*
Pneumonia
Pulmonary Edema
Pulmonary Fibrosis
Pulmonary Gas Exchange
Quality Control
Reflex
Respiration
Gases
Ions
Nitrogen Oxides
Nitrous Oxide