Invasive procedures in patients with haemophilia: Review of low-dose protocols and experience with extended half-life FVIII and FIX concentrates and non-replacement therapies.

The performance of surgery and invasive procedures in patients with haemophilia is currently facing new challenges globally. The first is the appropriate application of low-dose protocols of clotting factor concentrates (CFC) achieving adequate perioperative haemostasis in resource constraint environments. The increasing availability of CFC through humanitarian aid programmes allows more invasive surgeries to be performed for which efficacy and safety data should be more widely collected and reported. Second, extended half-life CFC that are increasingly available in many countries represent valuable alternatives to standard half-life products in surgical patients allowing reduced number of infusions and lower consumption, in particular for extended half-life factor IX. Third, in the era of recently introduced non-factor prophylaxis, some minor surgical procedures can now be performed without additional haemostatic treatment, others with few low-dose administrations of CFC or bypassing agents. Additional factor VIII or bypassing treatment has proven to be safe and effective in association with emicizumab for major surgeries, and it was effectively given at low doses in association with fitusiran. No thrombotic complications have been reported in the surgical setting so far. A multidisciplinary team/facility remains crucial to manage major surgery in patients on prophylaxis with these new agents.