Thromboprophylaxis

Lower limb trauma requiring immobilization is a very frequent condition that is associated with an increased risk of developing venous thromboembolism (VTE). The TRiP(cast) score has been developed to provide individual VTE risk stratification and help in thromboprophylactic anticoagulation decision. The recent CASTING study had confirmed that patients with a TRiP(cast) score \<7 have a very low risk of VTE and could be safely manage without prophylactic treatment. Conversely, patients with a score ≥ 7 have a high-risk of VTE and require a prophylactic anticoagulant treatment. Low molecular weight heparins (LMWH) have been shown to be effective in this indication. However, in the CASTING study, the 3-month symptomatic VTE rate was 2.6% in this subgroup despite LMWH prophylactic treatment. This result suggests that LMWH are not sufficiently effective in this particular subgroup of high-risk patients. Direct oral anticoagulants, and in particular rivaroxaban, may be an effective and safe alternative to LMWH. In the PRONOMOS study, comparing LMWH with rivaroxaban in patients who had undergone non-major lower limb surgery, the relative risk of symptomatic VTE was 0.25 (95% CI = 0.09 - 0.75) in favor of rivaroxaban 10mg. No significant increase in bleeding was found. In addition, as LMWH treatment requires subcutaneous daily injections, the use of rivaroxaban may positively impact patients' quality of life as well as being effective in medico-economic terms. The aims of this study are to demonstrate that rivaroxaban is at least as effective, easier to use and more efficient than LMWH in patients with trauma to the lower limb requiring immobilisation and deemed to be at risk of venous thromboembolism (TRiP(cast) score ≥ 7). High-risk patients are randomized to receive either rivaroxaban or LMWH. They are followed up at 45 days and 90 days to assess the occurrence of thrombotic events or bleeding, as well as their satisfaction with the treatment received.

Thromboprophylaxis is recommended for critically ill patients without contraindications and is usually achieved by the subcutaneous daily administration of a low dose of low molecular weight heparin (LMWH). The efficacy of this measure can be assessed by measuring the anticoagulation level obtained in the blood by dosing the anti-Xa activity. However, multiple studies have shown that anti-Xa activities in critically ill patients in the intensive care unit (ICU) are much lower, and below the desired range, than their ward counterparts. LMWH elimination depends on kidney function and reduced dosing is recommended for patients with renal failure, treated or not with renal replacement therapy (continuous veno-venous hemofiltration (CVVH)). However, some scarce data suggest that even critically ill patients with renal failure treated with reduced or even with standard doses of LMWH, also have lower anti-Xa activities (below the desired range). If confirmed, this finding may suggest that reduced or even standard dosing of LMWH for thromboprophylaxis in critically ill patients with renal failure should be replaced by another dosing regimen or another route of administration. Therefore, this study aims to better characterize the pharmacokinetic profiles of LMWH after administration of a prophylactic dose of enoxaparin daily in patients with renal failure treated or not with CVVH, and to compare them to patients with no renal failure.

The aim of this trial is to find out if a tablet called apixaban can reduce blood clots in people with lung cancer having chemotherapy or similar treatments. Apixaban is a type of oral anticoagulant ("blood thinner") that makes the blood less sticky to prevent blood clots forming. The trial is trying to find out if apixaban it can reduce blood clots in people with lung cancer. Participants will receive the following treatment: • Apixaban or placebo, 2.5mg taken by mouth twice a day for 6 months. This treatment will be taken in addition to any treatment that they are receiving to treat their lung cancer. Participants will need to: * Sign a consent form to enter the trial. * Take the trial treatment as directed by the research team * Complete a participant diary to record when they took the trial treatment * Complete the Quality of Life and Health resource use questionnaires. * Female participants of childbearing potential must use adequate contraception during the trial and for at least 2 days after trial treatment has finished.