Blood Donation Protocols
Using charts and infographics, this Demonstration shows the rules for matching blood types for donation.[more]
Selecting "infographics of group and Rh rules" specifically illustrates the selection rules for both the blood group and the Rh factor. Use the popup menus to select the blood group and associated Rh factor of both the donor and the recipient. If the blood groups are compatible, a green arrow is shown parallel to the arrow of the infographic; otherwise, a red arrow appears.
Selecting "table of rules and global infographics" shows the rules in the form of a chart, where the specific case selected is highlighted in yellow, and the general 3D infographic (blood group in black, Rh in red).
The arrows in the infographics can be hidden by using the two checkboxes.[less]
A blood donation is medically safe if both the groups and the Rh factors are compatible. Group compatibility is actually more restrictive than Rh factor compatibility. In fact, when the group rules are not followed, a hemolytic transfusion reaction (rupture of red blood cells) can take place, possibly resulting in a fatal response. When considering the Rh factor, the only restriction () could be bypassed in an emergency situation, provided that the recipient has not been exposed to the antigen in a previous transfusion or a previous pregnancy (in an woman with an child). Such previous exposure would produce, in the recipient, antibodies, which would bind with the blood, causing a hemolytic reaction and possible systemic damage.
Snapshot 1: donation is permissible for both the groups and the Rh factors
Snapshot 2: donation is forbidden because of incompatible groups
Snapshot 3: donation is forbidden because of incompatible Rh factors
Snapshot 4: the donation chart shows that the group can be considered as the universal donor (first, fully green column on the left) and the group can be considered as the universal recipient (bottom, fully green row).
 I. Asimov, The Bloodstream: River of Life, New York: Collier Books, 1961.