Due to associated diseases, the function of the spleen may be modified, in turn causing certain complications, such as anaemia, altered coagulation, malnutrition and organ failure. Preoperative management of patients must take these two possibilities into account. In non-traumatic splenectomies, blood samples are necessary to screen for thrombophilia: antithrombin III deficiency, protein C deficiency, protein S deficiency and dysplasminogenemia. Complete blood count, AST, ALT, serum amylase, C-reactive protein, thrombin-AT-III complex and D-dimer also become necessary perioperatively. The preoperative management of anaemia must evaluate the risk and benefits of blood transfusion. Malnutrition increases the risk of postoperative complications. Antibiotics are recommended for patients who are immunosuppressed and in trauma. In the classical form of spleen surgery, pain is a frequent symptom, with variable intensity, mostly due to the pressure applied to the ribs. If the pain is not well managed by specific pills, it is better to make an anaesthetic block of the thoracic nerves. Thrombosis extending into the portal vein is rare; with an overall risk of 3.3%. Infection is the most common postoperative complication. Fever commonly appears between the fourth and seventh day after surgery. The risk of thromboembolic events and pulmonary arterial hypertension varies greatly, depending on the underlying condition for which the splenectomy is performed and its association with intravascular haemolysis. The most serious septic complication after splenectomy is the (OPSI), which brings about a prohibitory mortality rate of 50% to 90%. Prevention of postsplenectomy sepsis has occurred through the use of greater efforts to avoid splenectomies.