Low-Flow Nasal Cannula Hydrogen Therapy

Abstract

Background: Molecular hydrogen (H 2) is a biologically active gas that is widely used in the healthcare sector. In recent years, on-site H 2 gas generators, which produce high-purity H 2 by water electrolysis, have begun to be introduced in hospitals, clinics, beauty salons, and fitness clubs because of their ease of use. In general, these generators produce H 2 at a low-flow rate, so physicians are concerned that an effective blood concentration of H 2 may not be ensured when the gas is delivered through a nasal cannula. Therefore, this study aimed to evaluate blood concentrations of H 2 delivered from an H 2 gas generator via a nasal cannula. Methods: We administered 100% H 2 , produced by an H 2 gas generator, at a low-flow rate of 250 mL/min via a nasal cannula to three spontaneously breathing micro miniature pigs. An oxygen mask was placed over the nasal cannula to administer oxygen while minimizing H 2 leakage, and a catheter was inserted into the carotid artery to monitor the arterial blood H 2 concentration. Results: During the first hour of H 2 inhalation, the mean (standard error (SE)) H 2 concentrations and saturations in the arterial blood of the three pigs were 1,560 (413) nL/mL and 8.85% (2.34%); 1,190 (102) nL/mL and 6.74% (0.58%); and 1,740 (181) nL/mL and 9.88% (1.03%), respectively. These values are comparable to the concentration one would expect if 100% of the H 2 released from the H 2 gas generator is taken up by the body. Conclusions: Inhalation of 100% H 2 produced by an H 2 gas generator, even at low-flow rates, can increase blood H 2 concentrations to levels that previous non-clinical and clinical studies demonstrated to be therapeutically effective. The combination of a nasal cannula and an oxygen mask is a convenient way to reduce H 2 leakage while maintaining oxygenation.

H2 Inhibits the Formation of Neutrophil Extracellular Traps

“…In the H 2 -exposed group, 100% hydrogen was administered via nasal cannula at a rate of 250 mL/min with spontaneous breathing, as previously reported. 35 We confirmed that the H 2 concentration in the carotid blood during H 2 inhalation was maintained at approximately 5%. After 3 hours of LPS administration, the main trunk of the PAs was exposed through a midthoracic incision, and blood was collected from the distal part after clamping the proximal part of the PAs ( Supplemental Figure 1B ).…”

Pharmacokinetics of hydrogen after ingesting a hydrogen-rich solution: A study in pigs

“…However, our earlier study found a very high concentration of H 2 in the carotid artery after a single inhalation of the gas, confirming that inhalation is the best way to supply H 2 to the entire body through the arterial blood [ 14 ]. Another study of ours used a different experimental system in which 100% H 2 was continuously inhaled through a nasal cannula; here, the H 2 concentration in the arterial blood matched the predicted value of the fraction of inspired H 2 , i.e., the concentration of H 2 in the gas mixture [ 15 ]. This experiment proved that the H 2 concentration in arterial blood is proportional to the partial pressure of H 2 in the inhaled gas mixture.…”

“…The lungs are specialized for gas exchange in that the thin type I alveolar epithelial cells (squamous epithelial cells), which have a thickness of 0.1–0.2 μm, are so close to the capillary wall (endothelial cells) that the two cannot be distinguished under a light microscope. In our above-mentioned experiment with inhaled H 2 , the H 2 saturation of the arterial blood instantly increased to a level comparable to the H 2 concentration in the alveoli [ 14 , 15 ]. However, the intestinal lumen is covered by a single layer of columnar epithelium, so the diffusion distance from the lumen to the capillaries is much greater than that from the pulmonary alveoli to the capillaries.…”

Molecular Hydrogen Positively Affects Physical and Respiratory Function in Acute Post-COVID-19 Patients: A New Perspective in Rehabilitation

“…Therefore, studies investigating the combination of H 2 administration with other rehabilitation programs would be important future work. H 2 administration seems to be a healthy, safe [ 20 , 29 , 65 ], well-tolerated therapeutic approach with no clinically significant health issues reported in animal model [ 37 , 43 ]. Therefore, we assume that H 2 could be potentially applied at health rehabilitation facilities (spa), post-COVID-19 care units, or during telerehabilitation in post-COVID-19 patients.…”

“…According to the operation manual, the H 2 generator provides H 2 at 99.99% purity, produced via purified water electrolysis using a membrane electrode assembly/proton exchange membrane. Inhalation of 100% H 2 produced by a H 2 generator through a nasal cannula, even at low flow rates (250 mL/min), was demonstrated to be an effective method of H 2 administration [ 43 ]. Participants could not distinguish between the inhalation of H 2 and placebo because H 2 is colorless, odorless, and tasteless [ 29 ].…”