Blood Conservation in Anaesthesia and Surgery - A Review

Abstract

Dangers to blood transfusion exist even when stringent methods are used to screen blood before transfusion. These dangers include blood transfusion reactions and the transmission of bacteria, viruses and protozoa to patients. Blood conservation adopts strategies that restrict the transfusion of homologous blood to patients. Conservation starts in the preoperative period and includes the diagnosis and management of anaemia. Augmentation of the preoperative haemoglobin can be achieved by using a combination of iron preparations, vitamins, protein supplementation, erythropoietin and treatment for malaria in suspected patients. Maintenance of the intravascular volume during surgery can be achieved using colloids and crystalloids. Blood conservation techniques, including induced hypotension, use of anti-fibrinolytics and acceptable forms of autologous blood transfusion reduce the need for allogeneic blood transfusion. Blood conservation methods are also important in critically ill patients and includes, accepting lower haemoglobin levels, restricting the amount of blood taken during phlebotomy and the use of erythropoietin/erythropoietin receptor agonists.