Efficiency and safety of the integrated use of medical gases thermal heliox, nitric oxide and molecular hydrogen in patients with exacerbation of chronic obstructive pulmonary disease complicated by hypoxemic, hypercapnic respiratory failure and secondary pulmonary arterial hypertension in the post-COVID period
Shogenova LV. · Ter Arkh. 2025;97(3):242–249.
What kind of evidence is this?
Human
Randomized comparative multi-arm study
Respiratory health
Inhaled H₂
Indeterminate for molecular hydrogen.
Clinical, functional and laboratory outcomes for complex co-interventions.
Methods at a glance
Patients with severe COPD after COVID-19.
100 participants in five intervention groups.
14 days.
Stabilized H₂ inhalation used in selected arms alongside thermal heliox and/or nitric oxide.
Inhaled H₂-containing gas within complex gas-treatment combinations.
Ninety-minute daily H₂ sessions; concentration and flow were not reported in the article.
Not reported.
Other gas interventions were separate or combined according to arm.
Multiple gas-combination arms and a control group.
Outcomes and reported result
Symptoms, respiratory function, exercise tolerance and laboratory measures.
The article reports differences across several multi-gas arms, but the design does not isolate a standalone H₂ effect.
The full article methods, intervention, outcomes, positive and null findings, funding and conflict statements were checked.
A reported association, difference or mechanism is not automatically a clinical benefit. Null findings, outcome type, study design and precision all matter.
Cautions and applicability
Complex co-interventions, limited intervention specification and single-author report prevent attribution to H₂.
The specific post-COVID COPD rehabilitation protocols only.
Cochrane RoB 2 — preliminary
High risk
Randomization details, concealment, blinding and arm-specific co-intervention balance were insufficiently established.
Random sequence reported or described · Allocation concealment not fully established · Deviations and co-interventions checked · Outcome measurement checked by endpoint · No outcome-level protocol comparison completed
No single-study GRADE certainty rating is assigned. Certainty is assessed by important outcome across a complete eligible evidence set, not by attaching a final grade to one source.
Sources and record status
PMID: 40327618 · DOI: 10.26442/00403660.2025.03.203131
A free publisher or repository full article was checked.
Publisher or repository full article and bibliographic record; checked 10 August 2026.
2026-08-10