Contamination of hospital compressed air with nitric oxide : Unwitting replacement therapy.
Inhaled nitric oxide (NO) at levels between 5 and 80 ppm has been used experimentally to treat a variety of conditions.
NO also is a common environmental air pollutant in industrial regions.
As compressed hospital air is drawn from the local environment, we speculated that it may contain NO contamination, which, if present, would provide unwitting inhaled NO therapy to all subjects respiring this compressed gas.
NO levels were measured twice daily from ambient hospital air and compressed gas sources driving positive pressure ventilation from two adjacent hospitals and compared with NO levels reported daily by local Environmental Protection Agency sources.
An NO chemiluminescence analyzer (sievers 270B ; Boulder, Colo) sensitive to =2 parts per billion was used to measure NO levels in ambient air and compressed gas.
NO levels in ambient air and hospital compressed air covaried from day to day, and absolute levels of NO differed between hospitals with the difference never exceeding 1.4 ppm (range, 0 to 1.4 ppm ; median, 0.07 ppm).
The hospital with the highest usage level of compressed air had the highest levels of NO, which approximated ambient levels of NO.
NO levels were lowest on weekends in both hospitals.
We also documented inadvertent NO contamination in one hospital occurring over 5 days, which corresponded to welding activity near the intake port for fresh gas.
This contamination resulted in systemwide NO levels of 5 to 8 ppm. (...)
Mots-clés Pascal : Dosage, Azote Oxyde, Air, Service hospitalier, Pneumologie, Hôpital, Exploration, Homme, Pollution air, Zone voisine
Mots-clés Pascal anglais : Assay, Nitrogen Oxides, Air, Hospital ward, Pneumology, Hospital, Exploration, Human, Air pollution
Notice produite par :
Inist-CNRS - Institut de l'Information Scientifique et Technique
Cote : 97-0342501
Code Inist : 002B30A02A. Création : 12/09/1997.