Bradycardia Risk Associated with Intravenous Dexmedetomidine: A Retrospective Study of Risk Factors and Clinical Outcomes in Critically Ill Patients (BRAID)

Bradycardia Risk Associated with Intravenous Dexmedetomidine: A Retrospective Study of Risk Factors and Clinical Outcomes in Critically Ill Patients (BRAID) | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Bradycardia Risk Associated with Intravenous Dexmedetomidine: A Retrospective Study of Risk Factors and Clinical Outcomes in Critically Ill Patients (BRAID) Albahi Malik, Navya Ramesh, Craig M. Coopersmith, Jonathan Sevransky, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7547505/v2 This work is licensed under a CC BY 4.0 License Status: Posted Version 2 posted You are reading this latest preprint version Show more versions Abstract Background Dexmedetomidine is a selective α2-adrenergic agonist commonly used for sedation in intensive care units (ICUs). While effective, it is associated with cardiovascular side effects, particularly bradycardia that may limit its use. Concerns about bradycardia-related complications often influence clinical decision-making regarding dexmedetomidine dosing and monitoring, yet the true clinical significance of this side effect remains unclear. This study aimed to identify risk factors for dexmedetomidine-associated bradycardia and evaluate its impact on clinical outcomes. Methods We conducted a retrospective cohort study involving adult patients who were mechanically ventilated and received dexmedetomidine for sedation across 12 ICUs in 4 hospitals under one hospital system. Bradycardia was defined as a heart rate below 60 beats per minute within 24 hours after dexmedetomidine administration. Multivariable logistic regression was employed to identify independent risk factors and assess the association between bradycardia and clinical outcomes, including inpatient mortality. Results Among 5,106 patients, 1,143 (22.4%) developed bradycardia. Independent risk factors for bradycardia included moderate/severe liver disease (OR 1.87, 95% CI 1.42–2.47), dementia (OR 1.67, 95% CI 1.21–2.31), cerebrovascular disease (OR 1.32, 95% CI 1.15–1.51), and cancer (OR 1.25, 95% CI 1.06–1.47). Lower risk of bradycardia included congestive heart failure (OR 0.71, 95% CI 0.63–0.80) and myocardial infarction (OR 0.73, 95% CI 0.63–0.85). Crude mortality rates were similar between groups (11.4% vs. 10.2%, p = 0.297), and after adjustment for age and illness severity, bradycardia was not independently associated with hospital mortality (adjusted OR 0.99, 95% CI 0.79–1.23, p = 0.915). Patients with bradycardia had shorter ICU length of stay compared to those without bradycardia (10.4 ± 10.1 vs. 10.8 ± 10.6 days, p = 0.012). A sensitivity analysis adjusting for minimum heart rate before dexmedetomidine initiation and using a stricter bradycardia definition of heart rate less than 50 bpm, resulted in similar findings. Conclusions Dexmedetomidine-associated bradycardia occurs in approximately one-quarter of ICU patients at out institution. Specific comorbidities significantly influence the risk of developing bradycardia, but dexmedetomidine-associated bradycardia itself may not associated with worse outcomes. Dexmedetomidine Bradycardia Critical care Risk factors Mortality Sedation Intensive care Full Text Additional Declarations The authors declare no competing interests. Supplementary Files BRAIDSupplementaryMaterials7.30.2025.docx Cite Share Download PDF Status: Posted Version 2 posted You are reading this latest preprint version Show more versions Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7547505","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":519189613,"identity":"36a7943c-f385-4abd-baf2-227159aeb949","order_by":0,"name":"Albahi Malik","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA/klEQVRIiWNgGAWjYBACNnYeBmYGA4bEBnbGZoYPMGEePFr4mSFaihuYGZsZZxCjRbIZpIWBob6BmYGZmYcYLQaHeQ9+LihgyO1vZm42tqnYJmc+I4Hxwds2fFr4kqVnGDDkzjjM2Jycc+a2scyNBGbDuXi18BhI8wC1NAC1HM5tu504QyKBTZoXjxb7wzzGv4FaEueDtFj+A2th/41PC9AWM5AtiRtADmNsgNjCjF8LX5o1j4FE4kagFsOeY7eNJXgeNkvOOYdHy/Hew7d5/tgkzjve/ljiR81tOQn25IMf3pTh1gIFEkhsgcQGgurRAP8BUnWMglEwCkbBMAcAs7FP23YjrfgAAAAASUVORK5CYII=","orcid":"","institution":"Emory University School of Medicine","correspondingAuthor":true,"prefix":"","firstName":"Albahi","middleName":"","lastName":"Malik","suffix":""},{"id":519189614,"identity":"bff573ee-ff87-4655-98e6-20da88b3b544","order_by":1,"name":"Navya Ramesh","email":"","orcid":"","institution":"Emory University School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Navya","middleName":"","lastName":"Ramesh","suffix":""},{"id":519189615,"identity":"d56a12ef-995d-4c25-9cfc-9fd95c9bde26","order_by":2,"name":"Craig M. 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While effective, it is associated with cardiovascular side effects, particularly bradycardia that may limit its use. Concerns about bradycardia-related complications often influence clinical decision-making regarding dexmedetomidine dosing and monitoring, yet the true clinical significance of this side effect remains unclear. This study aimed to identify risk factors for dexmedetomidine-associated bradycardia and evaluate its impact on clinical outcomes.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e\u003cp\u003eWe conducted a retrospective cohort study involving adult patients who were mechanically ventilated and received dexmedetomidine for sedation across 12 ICUs in 4 hospitals under one hospital system. Bradycardia was defined as a heart rate below 60 beats per minute within 24 hours after dexmedetomidine administration. Multivariable logistic regression was employed to identify independent risk factors and assess the association between bradycardia and clinical outcomes, including inpatient mortality.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e\u003cp\u003eAmong 5,106 patients, 1,143 (22.4%) developed bradycardia. Independent risk factors for bradycardia included moderate/severe liver disease (OR 1.87, 95% CI 1.42\u0026ndash;2.47), dementia (OR 1.67, 95% CI 1.21\u0026ndash;2.31), cerebrovascular disease (OR 1.32, 95% CI 1.15\u0026ndash;1.51), and cancer (OR 1.25, 95% CI 1.06\u0026ndash;1.47). Lower risk of bradycardia included congestive heart failure (OR 0.71, 95% CI 0.63\u0026ndash;0.80) and myocardial infarction (OR 0.73, 95% CI 0.63\u0026ndash;0.85). Crude mortality rates were similar between groups (11.4% vs. 10.2%, p\u0026thinsp;=\u0026thinsp;0.297), and after adjustment for age and illness severity, bradycardia was not independently associated with hospital mortality (adjusted OR 0.99, 95% CI 0.79\u0026ndash;1.23, p\u0026thinsp;=\u0026thinsp;0.915). Patients with bradycardia had shorter ICU length of stay compared to those without bradycardia (10.4\u0026thinsp;\u0026plusmn;\u0026thinsp;10.1 vs. 10.8\u0026thinsp;\u0026plusmn;\u0026thinsp;10.6 days, p\u0026thinsp;=\u0026thinsp;0.012). A sensitivity analysis adjusting for minimum heart rate before dexmedetomidine initiation and using a stricter bradycardia definition of heart rate less than 50 bpm, resulted in similar findings.\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e\u003cp\u003eDexmedetomidine-associated bradycardia occurs in approximately one-quarter of ICU patients at out institution. Specific comorbidities significantly influence the risk of developing bradycardia, but dexmedetomidine-associated bradycardia itself may not associated with worse outcomes.\u003c/p\u003e","manuscriptTitle":"Bradycardia Risk Associated with Intravenous Dexmedetomidine: A Retrospective Study of Risk Factors and Clinical Outcomes in Critically Ill Patients (BRAID)","msid":"","msnumber":"","nonDraftVersions":[{"code":2,"date":"2026-02-03 19:53:45","doi":"10.21203/rs.3.rs-7547505/v2","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}},{"code":1,"date":"2025-09-23 07:08:10","doi":"10.21203/rs.3.rs-7547505/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"6996fe3c-5044-4096-bf73-7ff69e3e84ab","owner":[],"postedDate":"February 3rd, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-11-28T06:38:46+00:00","versionOfRecord":[],"versionCreatedAt":"2026-02-03 19:53:45","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v2","identity":"rs-7547505","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7547505","identity":"rs-7547505","version":["v2"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}