Final answer:
The patient giving her arm to the phlebotomist exemplifies implied consent for a medical procedure. When blood agglutinates with anti-A and anti-B antibodies, it indicates an AB blood type. In emergencies, type O negative blood is transfused as it is the universal donor and carries less risk of reaction.
Step-by-step explanation:
A 19-year old patient's action of offering her arm to the phlebotomist is an example of implied consent. In healthcare, implied consent occurs when a patient's nonverbal behavior indicates willingness to undergo a medical procedure. In this case, by presenting her arm for the venipuncture, the patient is nonverbally communicating consent for the blood draw procedure. No error has been made by the technician in the blood typing process if both wells agglutinate upon the addition of the anti-A and anti-B antibodies. This response indicates that the patient's blood type is AB.
Understanding Blood Types
The agglutination of blood when mixed with anti-A and anti-B antibodies indicates the presence of both A and B antigens on the red blood cells, which characterizes blood type AB. In the second scenario provided, during a medical emergency where a patient's blood type cannot be immediately determined, type O negative blood is commonly transfused because it is the universal donor type and is less likely to cause an adverse reaction. The patient's blood type in the described laboratory test is AB, which is confirmed by the agglutination in the presence of both anti-A and anti-B antibodies.