{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,12]],"date-time":"2025-12-12T21:05:03Z","timestamp":1765573503565,"version":"3.48.0"},"reference-count":11,"publisher":"American Veterinary Medical Association (AVMA)","issue":"1","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["javma"],"published-print":{"date-parts":[[2026,1,1]]},"abstract":"Abstract<\/jats:title>\n \n Objective<\/jats:title>\n To determine if the combination of lidocaine and xylazine has a longer duration of action compared to lidocaine alone when administered as an inverted L block in steers.<\/jats:p>\n <\/jats:sec>\n \n Methods<\/jats:title>\n \n 6 healthy beef-cross steers were enrolled in a randomized crossover study. Both groups received an inverted L block using 6 mg\/kg of lidocaine. Group L received lidocaine only, and group LX received lidocaine and 0.02 mg\/kg of xylazine. There was a 5-day washout period between treatments. Following administration, the onset and duration of action were assessed through a series of needle pricks along the paralumbar fossa every minute for the first 15 minutes and then every 15 minutes until the return of sensation. Sedation scores and heart rates were also collected. Parametric data were analyzed with a paired\n t<\/jats:italic>\n test. Nonparametric data were analyzed with a Wilcoxon signed rank test. A\n P<\/jats:italic>\n value < .05 was considered significant. This study was completed in June 2023.\n <\/jats:p>\n <\/jats:sec>\n \n Results<\/jats:title>\n \n When administered as an inverted L block, the addition of xylazine to lidocaine significantly prolonged the duration of action from 130 \u00b1 43.1 minutes to 197.5 \u00b1 61.7 minutes (\n P<\/jats:italic>\n = .027). Sedation scores were higher in the LX treatment group (\n P<\/jats:italic>\n = .039). There was no difference between groups for onset of action time (\n P<\/jats:italic>\n = 1.0) or heart rate (\n P<\/jats:italic>\n = .89).\n <\/jats:p>\n <\/jats:sec>\n \n Conclusions<\/jats:title>\n The combination of lidocaine and xylazine, when administered as an inverted L block, prolongs the duration of blockade.<\/jats:p>\n <\/jats:sec>\n \n Clinical Relevance<\/jats:title>\n The addition of xylazine to lidocaine for administration as an inverted L block extends the duration of anesthetic effect, confers mild sedative properties, and is readily integrated into clinical practice.<\/jats:p>\n <\/jats:sec>","DOI":"10.2460\/javma.25.03.0186","type":"journal-article","created":{"date-parts":[[2025,8,8]],"date-time":"2025-08-08T17:25:40Z","timestamp":1754673940000},"page":"53-56","source":"Crossref","is-referenced-by-count":0,"title":["Xylazine prolongs the duration of action of inverted L blocks in steers"],"prefix":"10.2460","volume":"264","author":[{"given":"Kelley M.","family":"Varner","sequence":"first","affiliation":[{"name":"College of Veterinary Medicine, North Carolina State University, Raleigh, NC"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Maya K.","family":"Keefer","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, North Carolina State University, Raleigh, NC"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Maggie","family":"Mooring","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, North Carolina State University, Raleigh, NC"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7270-8874","authenticated-orcid":true,"given":"Earl","family":"Ford IV","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, North Carolina State University, Raleigh, NC"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kim","family":"Love","sequence":"additional","affiliation":[{"name":"K. R. Love Quantitative Consulting and Collaboration, Athens, GA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sarah E.","family":"Klein","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, North Carolina State University, Raleigh, NC"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1272","reference":[{"issue":"1","key":"ref1","series-title":"Vet Clin North Am Food Anim Pract","first-page":"83","article-title":"Herd-level monitoring and prevention of displaced abomasum in dairy cattle","volume":"34","author":"Caixeta LS","year":"2018","unstructured":"Caixeta LS, Herman JA, Johnson GW, McArt JAA Herd-level monitoring and prevention of displaced abomasum in dairy cattle. Vet Clin North Am Food Anim Pract. 2018;34(1):83-99. doi:10.1016\/j.cvfa.2017.10.002"},{"issue":"1","key":"ref2","series-title":"J Vet Med Surg","first-page":"23","article-title":"Comparison between distal paravertebral and line block anesthesia for laparotomy in goats","volume":"3","author":"Yadav S","year":"2019","unstructured":"Yadav S, Bostami M, Ryad H, Sarkar S, Sutradhar B Comparison between distal paravertebral and line block anesthesia for laparotomy in goats. J Vet Med Surg. 2019;3(1):23."},{"issue":"1","key":"ref3","series-title":"Vet Clin North Am Food Anim Pract","first-page":"11","article-title":"A review of analgesic compounds used in food animals in the United States","volume":"29","author":"Coetzee JF","year":"2013","unstructured":"Coetzee JF A review of analgesic compounds used in food animals in the United States. 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Vet Anaesth Analg. 2002;29(2):64-68. doi:10.1046\/j.1467-2995.2001.00068.x"},{"key":"ref8","series-title":"Pain Res Manag","first-page":"8858312","article-title":"The effect of dexmedetomidine in combination with bupivacaine on sensory and motor block time and pain score in supraclavicular block","volume":"2021","author":"Sane S","year":"2021","unstructured":"Sane S, Shokouhi S, Golabi P, Rezaeian M, Kazemi Haki B The effect of dexmedetomidine in combination with bupivacaine on sensory and motor block time and pain score in supraclavicular block. Pain Res Manag. 2021;2021:8858312. doi:10.1155\/2021\/8858312"},{"issue":"2","key":"ref9","series-title":"Vet Clin North Am Food Anim Pract","first-page":"211","article-title":"Local and regional anesthesia in cattle","volume":"24","author":"Edmondson MA","year":"2008","unstructured":"Edmondson MA Local and regional anesthesia in cattle. Vet Clin North Am Food Anim Pract. 2008;24(2):211-226, v. doi:10.1016\/j.cvfa.2008.02.013"},{"issue":"5","key":"ref10","series-title":"Anesthesiology","first-page":"1111","article-title":"Perineural dexmedetomidine added to ropivacaine causes a dose-dependent increase in the duration of thermal antinociception in sciatic nerve block in rat","volume":"111","author":"Brummett CM","year":"2009","unstructured":"Brummett CM, Padda AK, Amodeo FS, Welch KB, Lydic R Perineural dexmedetomidine added to ropivacaine causes a dose-dependent increase in the duration of thermal antinociception in sciatic nerve block in rat. 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