Bombay Blood Group
The Bombay blood group was discovered fifty years ago in Bombay as it included varied phenotypic characteristic when compared to the standard blood typing such as A, B and O. The RH factor of the blood groups were studied to understand the antigenic structures based on which the H antigenic characteristic became very important. The phenotypic characteristic of Bombay blood group was hence discovered as Oh wherein the 'h' represents its varied nature when compared to the other blood groups.
Bombay blood group contains 'h' characteristic. The RBCs are not agglutinated by the anti-A, anti-B. Bombay Blood group is not restricted only to Indians but is noticed among Caucasians, Japanese etc. Only about 0.01% of the world population has the Bombay blood group, which makes it an essential need to maintain a record of the respective blood type individuals for emergencies.
It is very easy to assume the blood group as O if the blood cells do not agglutinate with A and B antigens. However this may lead to adverse reactions such as hemolytic transfusion rejection when the respective blood group is transfused in to the patient. Confirmatory tests are essential to identify Bombay blood group - as the protein containing H antigen clearly differs from the O blood type. Therefore confirmatory tests such as anti-H lectin Ulex Europaeus are used to detect the presence of A ,B and OH types in the RBCs but does not agglutinate the Oh type.
Blood transfusion is one of the important procedures administered in healthcare centers to meet surgical and trauma needs. This procedure is categorized under transfusion medicine section. Blood transfusion is a high-risk procedure as it involves multiple protocols and guidelines for safe and effective transfusion.
Guidelines and Procedure
Transfusion medicine has high significance as it involves the transfusion of blood and blood products depending upon the patient needs. Blood required for the transfusion is obtained from blood banks, which are established either by the government or privately following NCCLS standards for the blood banks. The standards are evaluated by organizations such as WHO to set a uniform and global protocol for safe transfusion. Blood transfusion is predominantly done to increase the percentage of hemoglobin in anemic patients and also to replace vital components such as platelets and serum proteins in some medical conditions. Other reasons for blood transfusion is to replace the amount of blood lost during surgery or trauma. Patients suffering thrombocytopenia (any disorder in which there is an abnormally low amount of platelets) might be in need of platelet transfusion.
Blood banks are authorized by the government to collect blood of different groups. Some of the rare groups include B negative, O negative and Bombay blood group. In these situations, the names and the address of these respective rare blood types are noted to ensure timely availability in case of a transfusion request. Cancer patients also require transfusion in case of conditions such as leukemia and malignant carcinomas associated with spleen or bone marrow. Leukocyte reduction procedure is followed in some transfusion centers in order to minimize the incidence of transfusion-associated allergic reactions. All donors are checked for a three-month gap before the subsequent transfusion to facilitate fresh blood collection from the donors containing viable red blood cells.
Different types of Blood transfusions:
Fresh Whole Blood: This is mostly needed during cardiac surgery or massive hemorrhage. Fresh Whole blood has RBC, plasma and fresh platelets.
Packed RBC: This is mostly needed to raise the hematocrit (the proportion of total blood volume that is composed of red blood cells).
Frozen packed RBC: Stored for nearly 3 years, frozen packed RBC is sparingly used. It is often used for rare blood groups. Patients suffering severe leukoagglutinin reactions or anaphylactic reactions might need this.
Leukocyte-Poor Blood: Patients who suffer severe leukoagglutinin reactions might need this. It is an expensive process as WBC are removed by centrifugation.
Precautions and risks
Transfusion is a very important procedure and hence primary analysis of the donor blood is done in order to avoid blood borne sepsis, transfusion allergies and organ damage. The donor blood is always cross-matched with the recipient's in order to check the compatibility of the blood. All procedures are documented to ensure safety and tracking of a transfusion procedure, as it is associated with medico-legal protocols. The A and B antigens are the first check before transfusion. In emergencies, type O/Rh-negative blood can be given to any recipient and usually packed cells are given. The Rh factor has also to be tested. Blood from the donor is also investigated for infections such as HIV 1&2, HBV, HCV, and VDRL to ensure safe transfusion.
Blood is collected from the healthy donor in a blood bank by administering venipuncture procedure from the brachial region. The obtained blood is transported for immediate need in surgeries or stored for few days in case of a scheduled surgery having the requirement for the particular blood group. The transfusion requirement is clearly stated in the surgical form and the blood bank technicians provide number of units required on the given date. Some of the common side effects associated with blood transfusions are infections of both viral and bacterial origin obtained from an infected donor. Receipt of blood contaminated with gram-negative bacteria often causes septic shock, Disseminated intravascular coagulation or DIA (a large amount of procoagulant enters the blood stream over a short period of time, overwhelming the body’s ability to replenish coagulation factors and causing bleeding) and acute kidney injury. Receipt of blood with gram-positive bacteria causes fever and Bacteremia (presence of bacteria in blood) but rarely causes sepsis.
Bibliography / Reference
Collection of Pages - Last revised Date: January 20, 2019