Hydrogen inhalation in rehabilitation program of the medical staff recovered from COVID-19
Shogenova LV, Truong TT, Kryukova NO, et al. · Cardiovascular Therapy and Prevention. 2021;20(6):2986.
What kind of evidence is this?
Human
Randomized controlled parallel prospective study
Long COVID
Inhaled H₂
Not reported in this record.
Not reported in this record.
Methods at a glance
Healthcare workers recovering from COVID-19 with post-COVID symptoms.
60 randomized: hydrogen plus standard rehabilitation n=30 and standard rehabilitation n=30; 27 and 28 completed, respectively.
90 minutes daily for 10 days.
Hydrogen delivered by nasal cannula from a SUISONIA device for 90 minutes daily for 10 days, alongside standard rehabilitation.
The article calls the intervention an 'active form of hydrogen' from a metal-hydride source; it is not described as Brown's gas.
The full article does not report source-gas H₂ concentration or purity.
Not reported in the full article.
No O₂ concentration or O₂ flow is reported; no co-delivery is inferred.
Standard rehabilitation including physiotherapy and supportive medication.
Outcomes and reported result
Endothelial indices, 6-minute walking distance, blood gases, lactate, inflammatory markers and adverse effects.
The hydrogen group showed within-group changes in several measures, including 6-minute walk distance from 429±45 to 569±60 m. The article reports no procedure-related adverse effects; interpretation is limited by attrition and incomplete between-group reporting.
The free bilingual publisher full article, methods, tables, results and adverse-event statement 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
Small, apparently unblinded rehabilitation study with five dropouts and many endpoints. Several reported changes are within-group rather than clearly demonstrated treatment-versus-control effects. Gas concentration and flow are absent, and the article's unusual 'active hydrogen' chemical description should not be treated as established chemistry.
Healthcare workers in post-COVID rehabilitation under the reported protocol.
Not reported in this record.
Not reported in this record.
Not reported in this record.
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
OpenAlex ID: W3205504592 · DOI: 10.15829/1728-8800-2021-2986
Open-access publisher article.
Cardiovascular Therapy and Prevention full article; full-text extraction checked 8 August 2026.
2026-08-10