direct nerve contact appear necessary for the chronic pain syndrome to occur.
Hematoma, arterial puncture, and thrombosis
Arm complications such as hematoma and/or arm pain occur in about 30% of donors [74]. A hematoma occurs commonly after blood donation even though the arm is inspected, and donors are advised to apply pressure to the area. Usually these hematomas are not serious, but they cause some local discoloration of the antecubital fossa. A more serious but rare complication is the development of a large hematoma often due to arterial puncture. This can cause pressure on vessels or nerves and injury in the antecubital fossa. Reports of symptoms suggesting this type of complication should be dealt with urgently by the blood center so that the donor can receive rapid attention and drainage of the fossa if necessary to prevent more serious injury. Although rare, deep vein thrombosis of the upper extremities has been reported as a complication of whole blood donation [75, 76].
4.5 Therapeutic bleeding
Blood may be collected as part of therapy for diseases, such as polycythemia vera or hemochromatosis. Because the procedure is being performed as a therapy, these individuals are patients, not donors. Their medical assessment then is focused on determining that the phlebotomy is safe for the patient. The patients may meet all of the criteria for whole blood donation except for the presence of the disease for which they are undergoing phlebotomy. However, as described earlier in this chapter, blood collected as therapeutic bleeding is not routinely used for transfusion, although in recent years the FDA has allowed variances so that blood from patients with benign conditions, such as hemochromatosis or secondary polycythemia, may be distributed by blood centers for patient use.
4.6 Medical assessment of apheresis donors
General assessment
The selection of donors for plateletpheresis, leukapheresis, and plasmapheresis uses the same general criteria used for whole blood donors [1]. Because of the unique nature of apheresis, there are some additional donor requirements that are based on the unique complications that may occur from apheresis, the nature of the procedures, and the fact that because few red cells are removed, donors can undergo cytapheresis more often than whole blood donation. The amount of blood components removed from apheresis donors must be monitored. To be consistent with whole blood donation, not more than 200 mL of red cells may be removed in 8 weeks. If for some reason, such as instrument failure, it is not possible to return the red cells to the donor, then the donation is treated as if it were a whole blood donation, and the donor cannot donate again for 8 weeks. For consistency with plasma donation, not more than 1,000–1,200 mL of plasma per week may be retained. When donors undergo apheresis more often than every 8 weeks, this is referred to as “serial” donation, and cumulative records must be maintained of the details of these donations, and the records must be reviewed periodically to assure that requirements related to red blood cells and plasma are met. The laboratory testing of donors and apheresis components for nonbacterial pathogens is essentially the same as for whole blood donation. Thus, the likelihood of disease transmission from apheresis components is similar to whole blood components.
Plateletpheresis donors
In one study of 2,069 plateletphereses in 352 donors, or an average of six procedures per donor, the following important observations were made that formed the basis of subsequent FDA regulations for the selection and monitoring of cytapheresis donors: (a) among women, platelet counts averaged 12% higher than those of males; (b) about 3% of all donors had platelet counts less than 150,000/mL before their first platelet donation; (c) the preapheresis platelet count was the best predictor of the postapheresis platelet count; (d) if donors with a preapheresis count of less than 150,000 were excluded, only 13% of donations resulted in a postapheresis count of less than 100,000; (e) the platelet count decreased about 30% immediately after apheresis; (f) the platelet count returned to normal about 4–6 days after apheresis; and (g) there was a slight rebound in platelet count above the initial count about 8–11 days after apheresis. Although the decrease in platelet count varies with the procedure used, a decrease of 20–35% generally occurs and the platelet count returns to baseline levels about 4 days after donation [77]. The platelet count decreases less than expected based on the number of platelets collected [78] because platelets are mobilized during the apheresis procedure [79].
A platelet count is not necessary before the initial donation because the decrease in platelet count following donation is not so extensive as to create a risk for the donor. At least 48 hours must elapse between platelet donations. If donors are to donate more frequently than every 4 weeks, a platelet count must be done to ensure that it is at least 150,000/μL before a subsequent donation. The platelet count can be obtained before the donation, or a count obtained after a previous donation can be used. Platelet donors should not have taken aspirin or drugs that interfere with platelet function, or must wait the specified time interval for that drug before donating (e.g., 3‐day waiting period for aspirin).
Red cell loss
Collection of platelets, granulocytes, lymphocytes, or stem cells by cytapheresis results in very little red cell loss. Thus, red cell depletion is not considered a possible complication of any individual collection unless there is an instrument malfunction. However, because apheresis collections can occur with high frequency (e.g., 24 plateletpheresis collections in 12 months), cumulative red cell loss from test sampling can cause anemia and low ferritin stores [80].
Blood volume shifts
Because no more than 15% of the donor’s blood is extracorporeal at any time, there is no greater risk for blood volume shift than with whole blood donation. In addition, during apheresis, citrate and saline solutions are infused, replacing some of the lost blood volume. Thus, shifts in blood volume leading to hypotension are not a problem. Because of the administration of hydroxyethyl starch (HES) during leukapheresis as sedimenting agent, there was concern that a net increase in blood volume might occur because HES is also used as a blood volume expander. This could lead to hypertension or acute heart failure. The volume of HES administered ranges typically from 200 to 400 mL and, combined with the removal of approximately 50–200 mL of granulocyte concentrate, does not result in complications caused by excess blood volume.
Potential complications of serial donations
Because cytapheresis donors can donate more often than whole blood donors, there are some complications that could result from multiple frequent donations. These involve depletion of cells or plasma proteins.
Platelet depletion
Platelet depletion is a concern if donors undergo frequent plateletpheresis during a short period, although this was not observed in 352 donors who donated an average of six times [77].
Leukapheresis donors
Because the HES used in granulocyte collection is a blood volume expander, some blood banks use lower blood pressure levels than those used for whole blood donors when selecting granulocyte donors. This is not a requirement, however. Granulocyte donors usually receive corticosteroids, and many also receive granulocyte colony‐stimulating factor (G‐CSF) to increase their granulocyte count and the granulocyte yield (see Chapter 6). Thus, donors should be questioned about conditions that might be exacerbated by corticosteroids. These include hypertension, peptic ulcers, cataracts, and diabetes. Because corticosteroids are given to granulocyte donors, donation frequency is limited to prevent complications. If frequent donation is required, it needs to be
