Blood Transfusion Practices in Obstetrics

Abstract

It is the responsibility of the physician to take care of the necessary steps that a blood product is indicated, and the standard practices for the transfusion of the blood is observed. 7 Obstetric conditions linked with the requirement for blood transfusion might cause morbidity and mortality if not fared appropriately. The increasingly important issues in blood transfusion are adverse events associated with transfusion, including potential infection and potential transmission of prions, rising costs, and the possible future problems of availability. The aim of this review is to offer guidance about the appropriate use of blood products that neither compromises the affected woman nor exposes her to unnecessary risk. PHYSIOLOGICAL BASIS OF TRANSFUSIONThe major aim for transfusion of blood and its components is to: • Increase the oxygen-carrying capacity of the blood. • Replacement of clotting factors which are lost, consumed, or not produced. Underneath the normal situations, the delivery of oxygen to the tissues is 1000 mL/min and the oxygen consumption is 200 mL/min. Henceforth, the ratio of oxygen delivery to oxygen consumption is 5:1. In case of patients suffering from anemia, hypoxia, or myocardial failure in whom the utilization is enhanced, and the delivery of oxygen cannot be enhanced, this ratio of 5:1 will drop in the patient consuming up the inherent oxygen reserves. This situation continues until the ratio falls to 2:1 up to which level the patient rests stable. Thus, the reference to transfuse a patient must lay emphasis on compensatory capability of the patient and physiologic parameters and not only on the packed cell volume (PCV) as is the case normally. Transfusion, thus, is only necessary when patients cannot counterbalance for their anemia.When the compensatory mechanisms are normal with a tolerable oxygen delivery, it might not be obligatory to transfuse patients until the PCV drops below 16% (hemoglobin, Hb < 5.3 gm/dL) and in patients with poor compensatory mechanisms may only be advised when the PCV drops below 25% (Hb < 8.3 gm/dL). [8][9][10] Hemoglobin usually ranges between 12 and 18 gm/dL differing on race, age, sex, and medical condition. The capability of bearing the lower concentrations of Hb depends on: • The degree and size of blood loss.• State of tissue perfusion.• Preexisting cardiopulmonary disease.