protocolSection identificationModule nctId: NCT06357403, orgStudyIdInfo id: AntiXa-ICU 1881/2023, briefTitle: Association of Anti-factor Xa Activity With Venous Thromboembolism in Critically Ill Patients, acronym: AntiXa-ICU, statusModule overallStatus: NOT_YET_RECRUITING, startDateStruct date: 2024-05, primaryCompletionDateStruct date: 2026-05, completionDateStruct date: 2026-08, studyFirstPostDateStruct date: 2024-04-10, lastUpdatePostDateStruct date: 2024-04-10, sponsorCollaboratorsModule leadSponsor name: Medical University of Vienna, class: OTHER, descriptionModule briefSummary: The goal of this observational study is to analyse the association between anti-factor Xa activity (antiXa) and the occurence of venous thromboembolism (VTE; either deep vein thrombosis and/or pulmonary embolism) in critically ill patients who are admitted to an intensive care unit. The main questions it aims to answer are:* What is the association between antiXa and VTE?* What is the association between antiXa and symptomatic, respectively incidental, VTE?* How is pharmacological anticoagulation with enoxaparin related to measured antiXa?* What is the association between antiXa and bleeding complications.* What is the incidence of venous thromboembolism in patients treated at an intensive care unit?* How is the occurence of VTE related to patient-centred outcomes such as mortality, quality of life, length of stay and days outside of the intensive care unit/hospital., conditionsModule conditions: Thrombosis, conditions: Pulmonary Embolism, conditions: Enoxaparin, designModule studyType: OBSERVATIONAL, designInfo observationalModel: COHORT, timePerspective: PROSPECTIVE, enrollmentInfo count: 1300, type: ESTIMATED, armsInterventionsModule interventions name: Anti-factor Xa activity calibrated for enoxaparin, outcomesModule primaryOutcomes measure: Number of patients with new-onset venous thromboembolism, secondaryOutcomes measure: Number of patients with new-onset upper extremity deep vein thrombosis, secondaryOutcomes measure: Number of patients with new-onset lower extremity deep vein thrombosis, secondaryOutcomes measure: Number of patients with new-onset central vein thrombosis, secondaryOutcomes measure: Number of patients with new-onset symptomatic upper extremity deep vein thrombosis, secondaryOutcomes measure: Number of patients with new-onset symptomatic lower extremity deep vein thrombosis, secondaryOutcomes measure: Number of patients with new-onset incidental upper extremity deep vein thrombosis, secondaryOutcomes measure: Number of patients with new-onset incidental lower extremity deep vein thrombosis, secondaryOutcomes measure: Number of patients with new-onset pulmonary embolism, secondaryOutcomes measure: Number of patients with new-onset symptomatic pulmonary embolism, secondaryOutcomes measure: Number of patients with new-onset incidental pulmonary embolism, secondaryOutcomes measure: Number of patients with venous thromboembolism, secondaryOutcomes measure: Number of patients with deep vein thrombosis, secondaryOutcomes measure: Number of patients with pulmonary embolism, secondaryOutcomes measure: Number of patients with new-onset venous thromboembolism, secondaryOutcomes measure: Number of days with any bleeding, secondaryOutcomes measure: Number of days with major and/or fatal bleeding, secondaryOutcomes measure: Number of red blood cell concentrates administered, secondaryOutcomes measure: Number of days on which either procoagulant medication, platelet transfusion or fresh frozen plasma was administered, secondaryOutcomes measure: Length of stay in the intensive care unit, secondaryOutcomes measure: Length of stay in the hospital, secondaryOutcomes measure: Death, secondaryOutcomes measure: Days alive and out of the intensive care unit, secondaryOutcomes measure: Days alive and out of the hospital, secondaryOutcomes measure: European Quality of Life 5 Dimensions 5 Level Version (EQ-5D-5L) index value, secondaryOutcomes measure: European Quality of Life 5 Dimensions 5 Level Version (EQ-5D-5L) visual analogue scale, eligibilityModule sex: ALL, minimumAge: 18 Years, stdAges: ADULT, stdAges: OLDER_ADULT, contactsLocationsModule, hasResults: False