{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,25]],"date-time":"2026-05-25T09:08:24Z","timestamp":1779700104927,"version":"3.53.1"},"reference-count":34,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2026,5,12]],"date-time":"2026-05-12T00:00:00Z","timestamp":1778544000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Medicina"],"abstract":"<jats:p>Background and Objectives: Remimazolam and remifentanil are ultra-short-acting agents that are used for sedation and analgesia, respectively. Their combined effect on respiratory function is unclear. We evaluated whether co-administration produced dose-dependent respiratory depression and loss of consciousness (LOC) preceded oxygen desaturation. Materials and Methods: A randomized, double-blind trial was conducted from May to July 2024. Female patients (20\u201365 years; n = 108; American Society of Anesthesiologists physical status I\u2013II) undergoing elective gynecological surgery were selected. Patients received remifentanil via target-controlled infusion (TCI) at effect-site concentrations (Ce) of 1.0, 1.5, or 2.0 ng\/mL (Groups 1.0, 1.5, and 2.0) combined with a fixed Ce of 500 ng\/mL remimazolam. Respiratory variables, timing of LOC, bispectral index, and adverse events were recorded. Results: Respiratory depression increased in a dose-dependent manner. Jaw thrust was required in 52.8% of Group 1.0 and 91.7% of Group 2.0 (p &lt; 0.001). The need for 100% oxygen increased from 30.6% to 69.4% (p = 0.001). Minute ventilation decreased only in Group 2.0 (p = 0.008). Involuntary movements were frequent in Group 1.0 (p = 0.005). Conclusions: Remimazolam\u2013remifentanil co-administration via TCI induced dose-dependent respiratory depression and pre-LOC desaturation. Therefore, continuous monitoring and careful titration are essential.<\/jats:p>","DOI":"10.3390\/medicina62050940","type":"journal-article","created":{"date-parts":[[2026,5,25]],"date-time":"2026-05-25T08:06:26Z","timestamp":1779696386000},"page":"940","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Respiratory Depression Following Concomitant Infusion of Remimazolam and Remifentanil Using Targeted Effect-Site Concentrations: A Randomized Controlled Trial"],"prefix":"10.3390","volume":"62","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3342-4136","authenticated-orcid":false,"given":"Ha Yeon","family":"Kim","sequence":"first","affiliation":[{"name":"Department of Anesthesiology and Pain Medicine, Ajou University School of Medicine, 164 Worldcup-ro, Youngtong-gu, Suwon-si 16499, Gyeonggi-do, Republic of Korea"},{"name":"Department of Medicine, Ajou University School of Medicine, 164 Worldcup-ro, Youngtong-gu, Suwon-si 16499, Gyeonggi-do, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sang Kee","family":"Min","sequence":"additional","affiliation":[{"name":"Department of Anesthesiology and Pain Medicine, Ajou University School of Medicine, 164 Worldcup-ro, Youngtong-gu, Suwon-si 16499, Gyeonggi-do, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jee Hwan","family":"Moon","sequence":"additional","affiliation":[{"name":"Department of Anesthesiology and Pain Medicine, Ajou University School of Medicine, 164 Worldcup-ro, Youngtong-gu, Suwon-si 16499, Gyeonggi-do, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hyeongjin","family":"Kwak","sequence":"additional","affiliation":[{"name":"Department of Anesthesiology and Pain Medicine, Ajou University School of Medicine, 164 Worldcup-ro, Youngtong-gu, Suwon-si 16499, Gyeonggi-do, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9199-7157","authenticated-orcid":false,"given":"Soo Jung","family":"Park","sequence":"additional","affiliation":[{"name":"Department of Medicine, Ajou University School of Medicine, 164 Worldcup-ro, Youngtong-gu, Suwon-si 16499, Gyeonggi-do, Republic of Korea"},{"name":"Department of Anesthesiology and Pain Medicine, Anesthesia and Pain Research Institute, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,5,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1031","DOI":"10.1213\/00000539-199311000-00028","article-title":"Preliminary pharmacokinetics and pharmacodynamics of an ultra-short-acting opioid: Remifentanil (GI87084B)","volume":"77","author":"Glass","year":"1993","journal-title":"Anesth. 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