{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,29]],"date-time":"2026-10-29T13:39:55Z","timestamp":1793281195566,"version":"4.5.0"},"reference-count":26,"publisher":"Ovid Technologies (Wolters Kluwer Health)","issue":"3","license":[{"start":{"date-parts":[[2026,7,29]],"date-time":"2026-07-29T00:00:00Z","timestamp":1785283200000},"content-version":"unspecified","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"content-domain":{"domain":["lww.com","ovid.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2026,9]]},"abstract":"<jats:sec>\n                    <jats:title>Background:<\/jats:title>\n                    <jats:p>Venous thromboembolism (VTE) is a recognized and serious complication following bariatric surgery, with the majority of events occurring after hospital discharge. Low-molecular-weight heparin is the most commonly used thromboprophylactic agent in this population. Both enoxaparin and tinzaparin are widely used, but existing evidence suggests a significant proportion of patients with obesity fails to achieve prophylactic anti-Xa levels with either agent. No adequately powered, prospective, head-to-head randomized trial comparing these agents has been conducted in a bariatric surgery population.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods\/Design:<\/jats:title>\n                    <jats:p>The OAT-RCT is a single-center, prospective, open-label, parallel-group randomized controlled trial at St Vincent\u2019s University Hospital, Dublin. Adult patients undergoing laparoscopic sleeve gastrectomy or gastric bypass will be randomly allocated in a 1:1 ratio to receive either weight-based tinzaparin (Arm A) or weight-stratified enoxaparin (Arm B) for 21\u00a0days post-operatively. The primary endpoint is the proportion of patients achieving prophylactic anti-Xa levels (0.2\u20130.4 IU\/mL) at 3\u20135\u00a0hours after the third dose, measured on post-operative day 2. Secondary endpoints include 30-day bleeding events, VTE incidence, sub- and supra-prophylactic anti-Xa proportions, correlations between anti-Xa and body habitus, adverse drug reactions, and patient-reported treatment satisfaction using the validated TSQM-9 questionnaire at 6\u00a0weeks. A total of 180 participants (90 per arm) are required based on a formal power calculation.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Discussion:<\/jats:title>\n                    <jats:p>The OAT-RCT is the first adequately powered head-to-head randomized controlled trial comparing anti-Xa levels of tinzaparin and enoxaparin for VTE prophylaxis in bariatric surgery. The results will provide high-quality class I evidence to inform evidence-based prescribing guidelines for this rapidly growing surgical population.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1097\/sp9.0000000000000069","type":"journal-article","created":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T09:00:24Z","timestamp":1785402024000},"page":"20-27","update-policy":"https:\/\/doi.org\/10.1097\/lww.0000000000001000","source":"Crossref","is-referenced-by-count":0,"title":["The OAT-RCT study: the obesity anticoagulation thromboprophylaxis randomized controlled trial protocol"],"prefix":"10.1097","volume":"30","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8983-7231","authenticated-orcid":false,"given":"Czara","family":"Kennedy","sequence":"first","affiliation":[{"name":"Department of Upper GI and Bariatric Surgery, St Vincent\u2019s University Hospital, Dublin 4, Ireland"},{"name":"School of Medicine, University College Dublin, Belfield, Dublin 4, 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