Final answer:
The agglutination observed after adding anti-A and anti-B antibodies indicates a normal response, revealing the patient's blood type as AB positive. The process of blood typing via cross matching is crucial for blood transfusions, with type O blood used as a universal option in emergencies.
Step-by-step explanation:
When preparing a patient for surgery, it is crucial to determine their blood type accurately. In the case where a lab technician adds anti-A antibody to one well and anti-B antibody to another with the patient's blood sample and both wells agglutinate, this indicates that the patient's blood type is AB positive. This response is normal and implies that the patient's red blood cells have both A and B antigens on their surface. The technique used for blood typing is essential in ensuring compatibility for blood transfusions, with cross matching being a necessary step unless it's an emergency where type O blood can be used as it is considered the universal donor.
After a blood sample is collected in a glass tube and left for about an hour, the blood clots and the cellular components settle at the bottom due to gravity. The liquid portion that can be harvested above the clot is known as serum, which is plasma without the clotting factors, and is used for further blood analysis.
In emergencies, such as the scenario where a patient is critically injured with severe bleeding, there is no time for determining blood type. In such cases, type O blood is transfused because it is the most likely to be compatible with any recipient, regardless of their blood type.