Haematology

Could adjusting D-dimer thresholds to clinical probability reduce ultrasound use for suspected DVT? This 2022 appraisal of the Canadian 4D study examines diagnostic safety, excluded patient groups and the challenges of transferring its algorithm into UK pathways.

An August 2021 appraisal of therapeutic-dose heparin in hospitalised COVID-19 patients without ICU-level organ support. It examines the multiplatform trial's benefits, bleeding-risk exclusions and composite outcome, and explains why these findings differ from those in critically ill patients.

A March 2021 appraisal of anticoagulation trials in critically ill patients with COVID-19. Simon Carley and Dan Horner examine therapeutic-dose versus usual-care thromboprophylaxis, organ support outcomes and bleeding, explaining why the findings cannot simply be extended to ward patients or treatment of confirmed thrombosis.

Could early prehospital plasma help trauma patients with brain injury? This 2020 review examines a secondary analysis of PAMPer, its apparent survival signal and why post-hoc findings, uncertain mechanisms and unanswered neurological-outcome questions require caution before changing practice.

Can TEG or ROTEM improve outcomes when added to major haemorrhage care? Natalie May reviews the iTACTIC trial's comparison with conventional coagulation testing, separating faster treatment decisions from demonstrated patient benefit and examining the limits of its size and subgroup findings.

Dan Horner revisits the evidence on venous thromboembolism in COVID-19 as it stood in October 2020. The review examines how screening and case selection affect reported clot rates, the distinction between different thrombotic findings, and uncertainty around risk prediction and higher-dose anticoagulation.