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2366 Part XIII: Transfusion Medicine Chapter 138: Blood Procurement and Red Cell Transfusion 2367

population in the least-developed countries. Thus, industrialized coun- and uncertain safety to sophisticated supply systems and component
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tries utilize transfused blood products far more commonly. In developed availability equal to or surpassing those of the United States.
countries, especially Western Europe and parts of Asia, a governmental
agency usually oversees the blood collection activities, although the PROCUREMENT OF PLASMA
extent to which the government sets requirements and monitors or
inspects the blood collection system varies. In developed countries, the DERIVATIVES
basic processes of donor medical screening, blood collection, laboratory
testing, and preparation of blood components are similar to the system The plasma industry is separate from the blood banking system
found in the United States. In virtually all developed countries, blood is described above. Plasma can be subjected to a fractionation process
donated by volunteers because paid donors are associated with a higher to produce several medically valuable products referred to as plasma
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risk of disease transmission. The basic blood components—red cells, derivatives. Plasma fractionation is performed in manufacturing plants
platelets, and plasma—usually are available and apheresis instruments in batches of up to 10,000 L involving the pooling of plasma from a
are used to collect platelets. Plasma derivatives such as albumin, coag- large number of donors. Plasma for manufacture or fractionation into
ulation factor VIII, other plasma protein concentrates (coagulation derivatives can be obtained from units of whole blood, but this amount
factors or inhibitors, or complement factor-1 inhibitor) and immune of plasma is inadequate to meet the needs for plasma derivatives. Con-
globulins are available. sequently, large amounts of plasma are obtained by plasmapheresis in
However, in the developing world the blood supply is very lim- which only the plasma and not red cells or platelets are retained from
ited and components are often not available. Patients may be required the donor. Individuals can donate plasma up to two times per week and
to arrange for the blood they need so donors may be friends or fam- usually are paid because of the more extensive time commitment. This
ily members of patients or even individuals who have been paid by the plasma collection system usually is operated by for-profit organizations
patient’s family to donate the blood needed. Donor screening may not and functions separately from the system for whole-blood donation.
be as extensive, transmissible disease testing may be lacking, and equip- Approximately 29 million liters of plasma were collected in the
ment may be reused. These difficulties may be compounded by the pres- United States in 2013. Twenty-six plasma derivatives are approved for
ence of endemic transfusion-transmissible diseases for which screening licensure by the FDA. Disruption in the sources of plasma or in one
is difficult or expensive and thus not performed as extensively as in manufacturer’s plant can have serious consequences and create short-
more developed countries. Great strides have been made during the last ages of certain derivatives.
decade primarily from the U.S.-funded President’s Emergency Plan for The remainder of this chapter describes the blood collection sys-
AIDS Relief (PEPFAR) program. Thus, the availability of blood and its tem operated by voluntary community organizations to provide cellular
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components around the world varies widely, from inadequate supplies and whole-blood–derived components.
TABLE 138–1. United States Blood Supply System in RECRUITMENT OF BLOOD DONORS
2011*
Although most Americans will require a blood transfusion at some time
Number Percent in their lives, only about one-third of the U.S. population is eligible to
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Total units whole blood 15,721,000 100 donate blood, and only a small portion of those actually donate. Blood
donors are more likely than the general population to be male, age 30
Blood centers 14,686,000 93
to 50 years, white, employed, and have more education and higher
Hospitals 1,036,0000 7 income. It is generally believed that the most effective way to get some-
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Red blood cell transfusions 13,785,000 100 one to donate blood is to ask him or her personally. Factors such as
the convenience of donation, peer pressure, receipt of blood by a family
Allogeneic 13,785,000 99
member, and perceived community needs are important factors that are
Autologous 65,000 <1 superimposed onto the individual’s basic social commitments.
Directed 37,000 <1
Platelets–total dose 1,738,000 100 WHOLE-BLOOD DONOR SCREENING
SDP collected 2,516,000 92 The approach to the selection of blood donors is designed to (1) ensure
WB platelet concentrates 1,110,000 8 the safety of the donor and (2) obtain a high-quality blood component
Total platelets transfused* 9,875,000 that is as safe as possible for the recipient. Some specific steps that are
taken to ensure that blood is as safe as possible are the use of only vol-
Fresh-frozen plasma 5,926,000 — unteer blood donors; questioning of donors about their general health
Fresh-frozen plasma 4,089,000 — before their donation is scheduled; obtaining a medical history, includ-
transfused ing specific risk factors, before donation; conducting a brief physical
Cryoprecipitate 1,690,000 examination before donation; laboratory testing of donated blood;
checking the donor’s identity against a donor deferral registry; and pro-
Cryoprecipitate transfused 890,000 viding a method by which the donor can confidentially designate the
SDP, single-donor platelet concentrate prepared by plateletpheresis. unit as unsuitable for transfusion after the donation is completed.
One SDP is equivalent to five platelet concentrates; WB, whole-blood
derived platelet concentrate. Usually five units are pooled to obtain HEALTH HISTORY, PHYSICAL EXAMINATION, AND
a therapeutic dose. LABORATORY EXAMINATION OF THE BLOOD
Data from Whitaker BI, Henry, RA, World Health Organization:
National blood transfusion services [on the Internet]. www.who.int/ The health history is usually done by a computer-assisted self-interview.
bloodsafety/transfusion_services/en/. Accessed September 1, 2009. The questions designed to protect the safety of the donor include

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