Application of Molecular Hydrogen in Heart Surgery under Cardiopulmonary Bypass
Danilova DA, Brichkin YD, Medvedev AP, Pichugin VV, Fedorov SA, Taranov EV, Nazarov EI, Ryazanov MV, Bolshukhin GV, Deryugina AV. · Sovremennye Tehnologii v Medicine. 2021;13(1):71–77.
What kind of evidence is this?
Human
Non-randomized two-group perioperative study
Cardiovascular and circulatory health
Inhaled H₂
Not reported in this record.
Not reported in this record.
Methods at a glance
Adults undergoing cardiac surgery with cardiopulmonary bypass for acquired heart-valve disease.
20 patients: 16 men and 4 women; H₂ group n=11 and comparison group n=9.
From intubation through the end of the operation; exact inhalation time varied with surgery and was not reported as one duration.
H₂ was added to the ventilator breathing circuit immediately after tracheal intubation and continued throughout the operation.
Dilute inhaled molecular H₂ — not Brown's gas; no intentional O₂ co-intervention was described.
1.5–2.0% H₂ in the ventilator circuit.
Not reported — the complete article gives concentration but no total circuit flow, so H₂ mL/min cannot be calculated.
Carrier-gas composition, O₂ percentage and O₂ flow were not reported as intervention details.
Nine operated patients did not receive H₂. The article does not report random allocation or blinding.
Outcomes and reported result
Diene and triene conjugates and Schiff bases in arterial and venous blood at anesthesia induction, before and after cardiopulmonary bypass and on postoperative day one.
Selected within-group lipid-peroxidation measures changed during and after surgery, with a different pattern in the untreated group. Baseline marker values differed substantially and the article did not provide a clear randomized between-group estimate. No clinical outcome, organ injury, adverse-event comparison, recovery time, length of stay or mortality endpoint was reported.
The complete English journal/PMC article, patient groups, all four sampling stages, arterial and venous tables, exposure specification, funding and conflicts were checked; the absence of clinical outcomes and absolute gas flow is explicit.
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
Only 20 patients, unclear group formation, no reported randomization or blinding, important baseline marker differences, multiple within-group comparisons and only biochemical surrogate outcomes. The article reported no financial support and no conflicts of interest.
Adults undergoing valve surgery with cardiopulmonary bypass under this intraoperative protocol; it does not establish improved clinical recovery or safety.
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
PMID: 34513069 · DOI: 10.17691/stm2021.13.1.09
Free full article on the journal site and PubMed Central.
Modern Technologies in Medicine and PMC full articles plus PubMed metadata; full-text and article-status check completed 8 August 2026.
2026-08-10