{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T14:05:47Z","timestamp":1790172347971,"version":"4.1.0"},"reference-count":41,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T00:00:00Z","timestamp":1790121600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Vet. Sci."],"abstract":"<jats:sec>\n                    <jats:title>Objectives<\/jats:title>\n                    <jats:p>This study aimed to compare the analgesic efficacy of methadone and fentanyl infusions at a 50:1 dose rate in dogs after spinal surgery.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>In a prospective, randomized, blinded clinical trial, 42 dogs with intervertebral disk disease were evaluated at 1, 2, 4, 18, 24, 42, 48, 66, 72, 90, and 96\u202fh after extubation. Based on the treatment groups, the dogs received a presurgical bolus of 0.25\u202fmg\/kg methadone or 5\u202f\u03bcg\/kg fentanyl, followed by an intraoperative and postoperative opioid infusion. In the methadone (M) treatment group, the dogs received 0.2\u202fmg\/kg\/h methadone, which was reduced stepwise to 0.05\u202fmg\/kg\/h. In the fentanyl (F) treatment group, the initial dose of 5\u202f\u03bcg\/kg\/h was reduced stepwise to 1\u202f\u03bcg\/kg\/h. Assessments at each time point included a simple sedation score, vital parameters, pain scoring using the Glasgow Composite Measure Pain Scale (CMPS-SF), and sensory testing with von Frey filaments. Multiple Mann\u2013Whitney tests were used for the analysis of CMPS-SF scores and sedation scores. Vital parameters, between and within the groups, were analyzed using mixed-effects analysis and Dunnett\u2019s multiple comparison test. The need for rescue analgesia was assessed via survival analysis. The level of significance was set to \u03b1\u202f=\u202f5%.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>In the postoperative period, six dogs in group M and four dogs in group F required rescue analgesia. CMPS-SF scores were not different between the groups M and F and did not change significantly over time within the treatment groups. Tactile sensory thresholds were not different between the groups M and F.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Clinical significance<\/jats:title>\n                    <jats:p>Under the dosing regimens investigated, methadone did not provide superior postoperative analgesia compared to fentanyl. From a clinical perspective, both drugs provided effective postoperative analgesia in this heterogeneous cohort of dogs following spinal surgery.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fvets.2026.1873178","type":"journal-article","created":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T13:30:16Z","timestamp":1790170216000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Analgesic effect of methadone constant rate infusion is not superior to fentanyl constant rate infusion in dogs after spinal surgery: a prospective, randomized, blinded, clinical trial"],"prefix":"10.3389","volume":"13","author":[{"given":"Alexandra Friederike","family":"Sch\u00fctter","sequence":"first","affiliation":[{"name":"Small Animal Hospital, University of Veterinary Medicine Hannover","place":["Hannover, Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sabine Beate Rita","family":"K\u00e4stner","sequence":"additional","affiliation":[{"name":"Small Animal Hospital, University of Veterinary Medicine Hannover","place":["Hannover, Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ben","family":"Prause","sequence":"additional","affiliation":[{"name":"Small Animal Hospital, University of Veterinary Medicine Hannover","place":["Hannover, Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Julia","family":"T\u00fcnsmeier","sequence":"additional","affiliation":[{"name":"Small Animal Hospital, University of Veterinary Medicine Hannover","place":["Hannover, Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,9,23]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"e81","DOI":"10.1136\/vr.105844","article-title":"Intervertebral disc disease and aortic thromboembolism are the most common causes of acute paralysis in dogs and 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