The Influence of Perioperative Strategies on the Extent of in Orthopaedic Prosthetic Surgery

3.1 General objective To assess the extent of blood loss in prosthetic surgery, considering whether possible variables may influence, either positively or negatively, the extent of such loss. The primary objective is to evaluate the extent and variability of blood loss in comparison with the literature and in relation to the various intraoperative methods used. The assessment will be carried out by analysing the parameters (haemoglobin - haematocrit) in the immediate preoperative period and then on days 1-3 and 7. 3.2 Primary objective The primary objective is to assess the extent and variability of blood loss in comparison with the literature and in relation to the various intraoperative techniques used. The assessment will be carried out by analysing the parameters (haemoglobin - haematocrit) in the immediate preoperative period and then on days 1-3 and 7. 3.3 Secondary objectives * Long stay: i.e. whether blood loss has, on any occasion, altered the post-operative course and/or delayed orthopaedic discharge * General and/or local complications: such as the presence of haematomas, or a drop in haemoglobin levels requiring specific treatment and/or transfusions of packed red blood cells or plasma. This may also include difficulties with recovery, including delays in regaining the ability to walk and in overall recovery * Transfusion of blood or blood products: to be considered a 'relative failure' in preoperative preparation and/or the perioperative course 4\. STUDY DESIGN This is a retrospective, observational, single-centre study involving patients who underwent orthopaedic prosthetic surgery (hip, knee and shoulder) at the IRCCS Istituto Clinico San Siro between January 2025 and December 2025, with clinical data collection. The study will be conducted in accordance with Good Clinical Practice guidelines.