People in good health who weigh at least 110 pounds can donate a unit of blood as often as every 8 weeks. An interviewer will ask about travel outside the United States and a variety of activities that could indicate increased risk of the donor transmitting one of the infectious agents that can be present in blood. The prospective donor will have his or her temperature, pulse, blood pressure and weight recorded. If a low hematocrit or hemoglobin is found, the donor is temporarily deferred. After the individual is found to be qualified to donate blood, he or she goes to the donation area.
Much care is taken to make the donor as comfortable as possible.
A sterile, new needle, which is attached to a sterile plastic bag, is inserted into the vein. It usually takes less than 10 minutes to collect the unit of blood. After the donation is completed, the needle is removed from the arm and discarded. The donor is generally asked to rest for at least several minutes and refreshments such as fruit juices, cookies and crackers are served to supply quick energy. Before leaving, donors are advised to drink plenty of fluids for the next 24 hours and to be cautious about lifting heavy objects.