Every day in emergency departments across the world, lives are saved because blood is available when it is needed most. Whether treating victims of major road traffic accidents, managing severe postpartum haemorrhage or stabilising patients with life-threatening internal bleeding, timely access to compatible blood remains one of the cornerstones of modern emergency care.
For most patients, obtaining suitable blood is a straightforward process. However, for a small but significant group of individuals with rare blood types, finding compatible blood can become a race against time one that may determine survival itself.
As we observe World Blood Donor Day on June 14, it is important to highlight a lesser-known aspect of transfusion medicine: the critical role of rare blood groups and the importance of maintaining robust rare donor registries.
Beyond the ABO Blood Groups
Most people are familiar with the ABO and Rh blood group systems and know their blood type as A, B, AB or O, along with being Rh-positive or Rh-negative. However, these designations are fundamental; nonetheless, they are far from representing all aspects of human blood classification.
Scientists have classified over 40 blood group systems, each with numerous red cell antigens numbering in hundreds. The antigens referred to are proteins and carbohydrates on the red blood cells and are crucial for transfusion compatibility.
A rare blood group is one where the antigen missing on the cells is not only present but common among most individuals. In such cases, transfusion with conventionally matched blood may provoke serious immune-mediated reactions, making the identification of compatible donors exceptionally challenging.
When “Universal Donor” Blood Is Not Universal
In emergency medicine, O-negative blood is often regarded as the universal donor blood and is routinely used in life-threatening situations when there is insufficient time for complete compatibility testing. There are however certain exceptions.
The Bombay Blood Group (Oh phenotype) is one of such exceptions; a rare blood group which was discovered in India. Persons with this phenotype lack the H antigen which is a basic requirement before a person expresses the ABO group. As a result, such persons have natural antibodies against the H antigen.
In persons who have the Bombay phenotype, the transfusion of normal O-negative blood results in hemolysis leading to renal failure and possibly death.
The problem is that most people who have the Bombay blood type are not aware of it. During routine blood grouping tests, a person having the Bombay blood type can be considered to be of the O blood group unless he or she undergoes specialized tests for the same. The difference comes to light usually during compatibility testing done in a blood bank setting, even at a point where the patient might require immediate transfusions.
Even though the Bombay Blood Group is still rare on an international scale (1 in 1,000,000), its incidence is much higher in India (1 in 10,000).
Challenges in Emergency Medicine
Imagine a youth casualty who has been brought to the emergency unit due to a severe road accident. The patient is hypotensive, actively bleeding and requires immediate resuscitation.
Under standard protocols, emergency blood products are initiated while laboratory testing is underway. If subsequent testing reveals the presence of a rare blood group, the clinical situation changes dramatically. It is essential for the health care professionals not only to deal with the injuries of the patients but also coordinate speedily with the blood banks and registries of rare donors to locate compatible units of blood.
This scenario underlines the immense importance of well-organized donor network systems as well as coordination among the hospitals, blood centers, and volunteer donors, because the compatible blood might have to be located from far-off places as well.
Improving the System: How Individuals Can Help
Transfusion services require the involvement of the general public for their efficient functioning. Here are some things that individuals could do to help out:
1. Donate Blood Regularly
Individuals aged between 18 and 65 years, who are healthy and eligible, should consider donating blood regularly. Each blood donation goes a long way in improving the quality of blood banks and helps identify rare blood types through routine testing of blood donors. Most individuals with rare blood types are found when they donate blood voluntarily.
2. Investigate Unusual Blood Bank Results
If you have received notice that additional compatibility testing was required for your blood or that cross-matching had proven to be more difficult than normal, then you must investigate these results further with your physician or with a specialist from the blood bank. Likewise, any family members who have suffered from inexplicable transfusion reactions should receive extensive immunohematological testing.
3. Keep Your Blood Type Available
Patients whose blood type is classified as rare should ensure that information is readily available. The use of a medical alert card or the inclusion of the Medical ID application on one's phone would be helpful in emergencies when the patient might be unconscious and unable to relay his or her blood type.
A Tribute to Blood Donors
Despite remarkable advances in medicine, no technology can manufacture a complete substitute for human blood. The availability of blood products continues to depend entirely on the generosity of voluntary donors.
The people who have rare blood groups and come to help out in times of crisis by traveling great distances for blood donations deserve special mention as their dedication constitutes some of the best examples of altruism in the healthcare sector.
It must be noted that blood donation is not merely a matter of benevolence; rather, it is an act of cooperation, which serves as part of the safety net that supports emergency medicine.
On this World Blood Donor Day, we should appreciate both the act of blood donation and also the efforts of the rare blood donors. These donors ensure that whenever there is a need for blood, there will be adequate supplies of the exact type required for treatment.
Disclaimer: The views expressed in this article are of the author and not of Health Dialogues. The Editorial/Content team of Health Dialogues has not contributed to the writing/editing/packaging of this article.
