High-Dose Nitric Oxide From Pressurized Cylinders and Nitric Oxide Produced by an Electric Generator From Air

Stefano Gianni, Raffaele Di Fenza, Caio C Araujo Morais, Bijan Safaee Fakhr, Ariel L Mueller, Binglan Yu, Ryan W Carroll, Fumito Ichinose, Warren M Zapol, Lorenzo Berra, Stefano Gianni, Raffaele Di Fenza, Caio C Araujo Morais, Bijan Safaee Fakhr, Ariel L Mueller, Binglan Yu, Ryan W Carroll, Fumito Ichinose, Warren M Zapol, Lorenzo Berra

Abstract

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.

Keywords: electric NO generator; methemoglobin; nitric oxide; nitrogen dioxide; pulmonary vasodilator; spontaneous breathing.

Conflict of interest statement

Drs Zapol and Yu disclose a relationship with Third Pole. Dr Carroll discloses a relationship with UNITAID. Dr Berra discloses relationships with iNO Therapeutics, Praxair, Masimo, the National Institutes of Health, and Fast Grant. The remaining authors have disclosed no conflicts of interest.

Copyright © 2022 by Daedalus Enterprises.

Source: PubMed

3
Tilaa