{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T12:09:36Z","timestamp":1789992576321,"version":"4.0.1"},"reference-count":35,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,9,16]],"date-time":"2026-09-16T00:00:00Z","timestamp":1789516800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002811","name":"Cathay General Hospital","doi-asserted-by":"publisher","award":["111-CGH-FJU-03"],"award-info":[{"award-number":["111-CGH-FJU-03"]}],"id":[{"id":"10.13039\/501100002811","id-type":"DOI","asserted-by":"publisher"}]},{"award":["111-CGH-FJU-03"],"award-info":[{"award-number":["111-CGH-FJU-03"]}],"id":[{"id":"https:\/\/ror.org\/03c8c9n80","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100013784","name":"Fu Jen Catholic University","doi-asserted-by":"publisher","award":["PL-202108018-V"],"award-info":[{"award-number":["PL-202108018-V"]}],"id":[{"id":"10.13039\/501100013784","id-type":"DOI","asserted-by":"publisher"}]},{"award":["PL-202108018-V"],"award-info":[{"award-number":["PL-202108018-V"]}],"id":[{"id":"https:\/\/ror.org\/04je98850","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Medicina"],"abstract":"<jats:p>Background and Objectives: Postoperative pain after endoscopic discectomy may reflect acute surgical nociception superimposed on pre-existing radicular symptoms. Molecular hydrogen (H2) has antioxidant and anti-inflammatory properties, but clinical evidence for perioperative analgesia is limited. We evaluated the association between perioperative H2 inhalation and postoperative pain and analgesic requirements. Materials and Methods: This open-label, non-randomized pilot study enrolled 37 patients in two consecutive periods (H2, n = 25; control, n = 12). Because original outcome records for 12 H2-period participants could no longer be retrieved at the time of manuscript preparation, the complete-case clinical analysis included 25 source-verifiable participants (H2, n = 13; control, n = 12). H2 was delivered via nasal cannula as a 66.7% H2\/33.3% O2 source gas at 2 L\/min (estimated inspired H2 approximately 4%). Pain was evaluated with a numerical rating scale (NRS) preoperatively, at post-anesthesia care unit (PACU) arrival, at 1, 6, 12, and 24 h, and at 1 month. Longitudinal scores were analyzed using generalized estimating equations with Holm-adjusted comparisons. A parallel exploratory murine chronic constriction injury (CCI) experiment (n = 6\/group) assessed mechanical allodynia over 14 days of daily H2 inhalation. Results: The group-by-time interaction was significant (Wald \u03c72(6) = 56.68, p &lt; 0.001). After Holm adjustment, pain scores were lower with H2 at PACU arrival (difference, \u22123.21; adjusted p = 0.002), 1 h (\u22122.42; adjusted p = 0.004), and 1 month (\u22123.45; adjusted p &lt; 0.001). Intraoperative fentanyl use and rescue analgesic use were also lower in the H2 group; no adverse events were documented in the analyzed cohort. In the murine CCI experiment, H2-treated mice showed higher ipsilateral paw withdrawal thresholds than air-exposed controls. Conclusions: Perioperative H2 inhalation was associated with lower pain scores at selected time points and reduced analgesic requirements. These preliminary findings require confirmation in randomized trials. Trial registration: ClinicalTrials.gov NCT05476575.<\/jats:p>","DOI":"10.3390\/medicina62091785","type":"journal-article","created":{"date-parts":[[2026,9,16]],"date-time":"2026-09-16T13:50:27Z","timestamp":1789566627000},"page":"1785","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Perioperative Hydrogen Inhalation and Postoperative Pain After Endoscopic Discectomy: A Pilot Non-Randomized Clinical Study with Exploratory Murine Data"],"prefix":"10.3390","volume":"62","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0461-2050","authenticated-orcid":false,"given":"Chao-Hsien","family":"Sung","sequence":"first","affiliation":[{"name":"Division of Anesthesiology, Fu Jen Catholic University Hospital, Fu Jen Catholic University, New Taipei City 24352, Taiwan"},{"name":"Ph.D. Program in Pharmaceutical Biotechnology, Fu Jen Catholic University, New Taipei City 242062, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"funding-acquisition","vocabulary":"credit"},{"role":"project-administration","vocabulary":"credit"}]},{"given":"Wen-Chin","family":"Ko","sequence":"additional","affiliation":[{"name":"School of Medicine, Fu Jen Catholic University, New Taipei City 242062, Taiwan"},{"name":"Division of Cardiac Electrophysiology, Department of Cardiovascular Center, Cathay General Hospital, Taipei 10630, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"funding-acquisition","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5201-6747","authenticated-orcid":false,"given":"Chia-Chi","family":"Kung","sequence":"additional","affiliation":[{"name":"Division of Anesthesiology, Fu Jen Catholic University Hospital, Fu Jen Catholic University, New Taipei City 24352, Taiwan"},{"name":"School of Medicine, Fu Jen Catholic University, New Taipei City 242062, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"funding-acquisition","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3478-5451","authenticated-orcid":false,"given":"Chi-Feng","family":"Hung","sequence":"additional","affiliation":[{"name":"Ph.D. Program in Pharmaceutical Biotechnology, Fu Jen Catholic University, New Taipei City 242062, Taiwan"},{"name":"School of Medicine, Fu Jen Catholic University, New Taipei City 242062, Taiwan"},{"name":"School of Pharmacy, Kaohsiung Medical University, Kaohsiung 80708, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"861","DOI":"10.1002\/ejp.838","article-title":"Neuropathic low back pain in clinical practice","volume":"20","author":"Baron","year":"2016","journal-title":"Eur. 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