PT - JOURNAL ARTICLE AU - Stefano Gianni AU - Raffaele Di Fenza AU - Caio C Araujo Morais AU - Bijan Safaee Fakhr AU - Ariel L Mueller AU - Binglan Yu AU - Ryan W Carroll AU - Fumito Ichinose AU - Warren M Zapol AU - Lorenzo Berra TI - High-Dose Nitric Oxide From Pressurized Cylinders and Nitric Oxide Produced by an Electric Generator From Air AID - 10.4187/respcare.09308 DP - 2022 Feb 01 TA - Respiratory Care PG - 201--208 VI - 67 IP - 2 4099 - http://rc.rcjournal.com/content/67/2/201.short 4100 - http://rc.rcjournal.com/content/67/2/201.full AB - BACKGROUND: High-dose (≥ 80 ppm) inhaled nitric oxide (INO) has antimicrobial effects. We designed a trial to test the preventive effects of high-dose NO on coronavirus disease 2019 (COVID-19) in health care providers working with patients with COVID-19. The study was interrupted prematurely due to the introduction of COVID-19 vaccines for health care professionals. We thereby present data on safety and feasibility of breathing 160 ppm NO using 2 different NO sources, namely pressurized nitrogen/NO cylinders (INO) and electric NO (eNO) generators.METHODS: NO gas was inhaled at 160 ppm in air for 15 min twice daily, before and after each work shift, over 14 d by health care providers (NCT04312243). During NO administration, vital signs were continuously monitored. Safety was assessed by measuring transcutaneous methemoglobinemia (SpMet) and the inhaled nitrogen dioxide (NO2) concentration.RESULTS: Twelve healthy health care professionals received a collective total of 185 administrations of high-dose NO (160 ppm) for 15 min twice daily. One-hundred and seventy-one doses were delivered by INO and 14 doses by eNO. During NO administration, SpMet increased similarly in both groups (P = .82). Methemoglobin decreased in all subjects at 5 min after discontinuing NO administration. Inhaled NO2 concentrations remained between 0.70 ppm (0.63–0.79) and 0.75 ppm (0.67–0.83) in the INO group and between 0.74 ppm (0.68–0.78) and 0.88 ppm (0.70–0.93) in the eNO group. During NO administration, peripheral oxygen saturation and heart rate did not change. No adverse events occurred.CONCLUSIONS: This pilot study testing high-dose INO (160 ppm) for 15 min twice daily using eNO seems feasible and similarly safe when compared with INO.