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There are 3 categories of blood donors:
Allogeneic Donations General Donor Requirements Allogenic blood donors should be 17 years or older, weigh 110 pounds or more, and should not have donated blood in the past 8 weeks. They must be in good health and feel well on the day of donation. They must have a negative history for hepatitis or jaundice after the age of 11 and not participate in any high risk behavior associated with HIV transmission. They should also be free of cancer and heart disease. Donation Process The total donation process takes about 1 hour and includes
The blood collection facility has the responsibility of protecting both the donor and the recipient. The donor must answer very specific questions about his/her health and high risk activity practices. These questions are designed to prevent injury to the donor during donation and to prevent transmission of an infectious or other harmful agent to the recipient. The questions contained in the Uniform Donor History Questionairre include: Are you 1. Feeling healthy and well today? 2. Currently taking an antibiotic? 3. Currently taking any other medication for an infection? Please read the Medication Deferral List. 4. Are you now taking or have you ever taken any medications on the Medication Deferral List (Proscar, Propecia, Avodart, Accutane, Soriatane, Tegison, growth hormone from human pituitary glands, bovine insulin, hepatitis B immune globulin)? 5. Have you read the educational materials and had your questions answered? In the past 48 hours 6. Have you taken aspirin or anything that has aspirin in it? In the past 6 weeks 7. Female donors: Have you been pregnant or are you pregnant now? In the past 8 weeks have you 8. Donated blood, platelets or plasma? 9. Had any vaccinations or other shots? 10. Had close contact with the smallpox vaccination site of someone else? In the past 16 weeks 11. Have you donated a double unit of red cells using an apheresis machine? In the past 12 months have you 12. Had a blood transfusion? 13. Had a transplant such as organ, tissue, or bone marrow? 14. Had a graft such as bone or skin? 15. Come into contact with someone else's blood? 16. Had an accidental needle-stick? 17. Had sexual contact with anyone who has HIV/AIDS or has had a positive test for the HIV/AIDS virus? 18. Had sexual contact with a prostitute or anyone else who takes money or drugs or other payment for sex? 19. Had sexual contact with anyone who has ever used needles to take drugs or steroids, or anything not prescribed by their doctor? 20. Had sexual contact with anyone who has hemophilia or has used clotting factor concentrates? 21. Female donors: Had sexual contact with a male who has ever had sexual contact with another male? 22. Had sexual contact with a person who has hepatitis? 23. Lived with a person who has hepatitis? 24. Had a tattoo? 25. Had ear or body piercing? 26. Had or been treated for syphilis or gonorrhea? 27. Been in juvenile detention, lockup, jail, or prison for more than 72 hours? In the past three years have you 28. Been outside the United States or Canada? From 1980 through 1996, 29. Did you spend time that adds up to three (3) months or more in the United Kingdom? 30. Were you a member of the U.S. military, a civilian military employee, or a dependent of a member of the U.S. military? From 1980 to the present, did you 31. Spend time that adds up to five (5) years or more in Europe? 32. Receive a blood transfusion in the United Kingdom ? From 1977 to the present, have you 33. Received money, drugs, or other payment for sex? 34. Male donors: had sexual contact with another male, even once? Have you EVER 35. Had a positive test for the HIV/AIDS virus? 36. Used needles to take drugs, steroids, or anything not prescribed by your doctor? 37. Used clotting factor concentrates? 38. Had hepatitis? 39. Had malaria? 40. Had Chagas' disease? 41. Had babesiosis? 42. Received a dura mater (or brain covering) graft? 43. Had any type of cancer, including leukemia? 44. Had any problems with your heart or lungs? 45. Had a bleeding condition or a blood disease? 46. Had sexual contact with anyone who was born in or lived in Africa? 47. Been inAfrica? 48. Have any of your relatives had Creutzfeldt-Jakob disease? Physical Exam During the medical review a physical exam is performed to document weight, temperature, pulse, blood pressure, hemoglobin or hematocrit. An arm inspection is done to look for skin lesions and signs of possible IV drug abuse.
Donor Deferral Rate Approximately 13% of blood donors are deferred prior to donation because they do not meet one or more of the medical history or physical exam criteria. Low hemoglobin is the most common cause for deferral, affecting 7-8% of donors. Blood Donation Blood is collected using aseptic technique and a sterile, FDA-approved collection bag. Equipment comes as single-use, disposable items, so donors cannot contract hepatitis or AIDS during blood donation. Approximately 450 mL of whole blood is collected into the blood bag. An additional 20-30 mL blood is collected into tubes for laboratory testing. The total amount withdrawn is 10 to 12% of the donor's total blood volume. Only 1 to 2% of donors experiences an adverse reaction to the donation. The most common problem is a vasovagal reaction. Symptoms may include transient low blood pressure, lightheadedness, or fainting during or following the donation. Symptoms usually resolve within minutes. Recovery Period After donation, donors are required to rest for 15 minutes and take some refreshments. Post phlebotomy instructions recommend drinking more fluids than usual and avoiding immediate use of cigarettes or alcohol. Most donors resume normal activity after 30 minutes. However, donors with high risk occupations or hobbies (policemen, construction workers, pilots, etc) should consider special precautions. With adequate fluid intake, blood volume is restored within 12 hours, but red cell volume is not restored for several weeks. Donor Testing The tubes of blood collected with the donor unit are used for testing in accordance with American Association of Blood Banks (AABB) and federal regulations. These are described in the FDA required "Circular of information for the use of human blood and blood components" and are summarized below. ABO & Rh type - Results are indicated in large letters on the label. Antibody Screen - Only donors with a history of transfusion or pregnancy need be tested for unexpected red cell antibodies. However, most collecting facilities perform this test on all donors. When such antibodies are found the plasma portion of the unit is not used for allogenic transfusion. Infectious Disease Tests - An increasing number of serologic and nucleic acid amplification tests have been added since the 1970's to detect infectious diseases.
Donations with reactive test results are destroyed regardless of subsequently obtained confirmatory test results as a precautionary measure to prevent infectious units from entering the blood supply. Donors with abnormal tests are notified of the results and asked not to donate again. This information is handled with strict confidentiality. Donor names are placed on a donor deferral list maintained in-house. Some results are also reported to the public health department. The infectious disease tests performed at each donation are summarized below. Serologic Test for Syphilis - This test was initiated in the 1940's. Today is it known that acquiring syphilis from a transfusion is extremely rare. Nevertheless, the test is still required by the FDA. Although its use is justified as an indicator for high risk behavior for AIDS, there are no data to support this assumption. Hepatitis B Surface Antigen (HBsAg) - A radioimmunoassay was introduced in the early 1970s to detect hepatitis B virus carriers and was later replaced with an enzyme immunoassay (EIA). Antibody to Human Immunodeficiency Virus (Anti-HIV) - An EIA was licensed by the FDA in March 1985. Reactive screening tests are confirmed with either Western Blot or immunofluorescence testing. Current methods detect infection with either HIV-1 or HIV-2. Antibody to Hepatitis B Core Antigen (Anti-HBc) - An EIA was initiated in November 1986 as an indirect or surrogate marker for non-A,non-B hepatitis. The test was licensed by the FDA in 1990 as a test to further reduce the transmission of Hepatitis B. This test has many false positives and has poor specificity. Alanine Aminotransferase (ALT) -Measurement of serum enzyme activity was introduced in November 1986 as a surrogate marker for non-A,non-B hepatitis. ALT has very poor specificity for viral hepatitis. ALT levels have not been required for volunteer blood donors in the U.S. since July 1995, but are still performed due to requirements for source plasma. Antibody to Human T-cell Lymphotrophic Virus I & II (Anti-HTLV l/II) - An EIA was implemented in February 1989. Current kits detect both HTLV-I and HTLV-II. A complicated algorithm is followed to distinguish between these two viruses that involves a second manufacturer's EIA, immunofluorescent antibody test, and recombinant immunoprecipitation assay (RIPA). Antibody to Hepatitis C Virus (Anti-HCV) - An EIA was implemented in May, 1990 to detect donors exposed to HCV, previously called non-A, non-B hepatitis. A second generation test was introduced in 1992 and a third generation test in 1994. HIV-1 p24 Antigen - An EIA was licensed in March 1996 as an additional test to prevent HIV transmission from donors who are in the early stages of infection and who have not yet developed antibody. The addition of HIV antigen testing reduced the window period between the time that a person contracts HIV and when the viruses can be detected from 22 days with HIV antibody alone to 16 days. FDA allowed HIV antigen testing to be discontinued after licensing of the NAT HIV test. NAT for HCV & HIV - Nucleic Acid Testing for HCV & HIV was introduced to test minipools of plasma from 16 donors as a clinical trial under an investigational new drug (IND) protocol in June 1999. FDA licensed the first nucleic acid test system for the simultaneous detection of HIV and HCV RNA on Feb 28, 2002. NAT has reduced the window period for HCV from 70 days (with EIA) to 10 days and for HIV from 22 days to 11 days. Approximately 4 per 1 million blood donations are from donors who are anti-HCV negative and HCV RNA positive. NAT for West Nile Virus - Nucleic acid testing for West Nile Virus was introduced July 2003. Bacterial culture - A method to limit or detect bacteria in all platelet products must be implemented by March 2004. Blood Component Preparation Most blood is collected as whole blood and then processed into one or more the following components: Red Blood Cells, Plasma and Platelets. Blood is collected into either 450 mL or 500 mL bags containing approximately 63 or 70 mL of anticoagulant-preservative solution, respectively. The anticoagulant is usually either citrate phosphate dextrose (CPD) or citrate phosphate dextrose adenine (CPDA1). CPD is chosen if the Red Blood Cell unit will be enriched with an additive solution. An example of the latter is Adsol (AS-1), which contains saline, adenine, dextrose and mannitol. Additive solutions increase the shelf life of Red Blood Cells from 35 to 42 days. The most commonly used blood collection bag system is composed of three bags; a primary collection bag containing CPD into which whole blood is drawn, a satellite bag containing Adsol, and an empty satellite bag. Following collection, the triple bag is centrifuged at a slow speed to separate red cells from platelet rich plasma (PRP). The PRP is transferred into the satellite bag. Adsol is added to the RBC bag, which is then clamped, removed sterilely, and stored at 1-6oC for up to 42 days. PRP is then centrifuged a second time at a faster speed to separate platelets and plasma. The supernatant contains platelet poor plasma, which is expressed into a satellite bag and frozen within 8 hours at -18oC. This component is labeled as Fresh Frozen Plasma (FFP). The remaining platelet concentrate consists of platelets suspended in approximately 50 mL of plasma. It is allowed to stand at room temperature (20 - 24oC) for one hour and then placed on a platelet rotator for storage up to 5 days at room temperature. If cryoprecipitate is to be prepared from FFP, the FFP is allowed to freeze for 24 hours and then thawed in a refrigerator. After thawing to a slush stage, FFP is spun in a refrigerated centrifuge to separate the cryoprecipitate from plasma. The supernatant plasma is removed, leaving cryoprecipitate suspended in approximately 15 mL of plasma. The cryoprecipitate is stored frozen at -18oC for up to 12 months. The cryosupernatant or cryo-poor plasma can also be refrozen and stored for up to 12 months.
Leukocytes can be removed from cellular components by the use of leukocyte reduction filters, which are special filters that have a strong affinity for leukocytes. Red blood cells can be filtered either immediately after collection, which is called prestorage leukocyte reduction, or at the time of transfusion, which is called bedside filtration. Prestorage leukocyte reduction is preferred because it removes leukocytes before they can release cytokines. Also, prestorage filtration ensures better quality control over the filtration process. Autologous Donation Autologous donor programs allow a patient to donate blood for their own use. Autologous transfusion indicates that the blood donor and transfusion recipient are identical. This is the safest possible transfusion a patient can receive and is an excellent option for patients facing elective surgery. Autologous collections should be used as part of a comprehensive strategy of blood conservation that includes careful attention to the proper indications for transfusion, acceptance of normovolemic anemia and avoidance of excessive blood sampling for diagnostic testing. Autologous donation is a safe procedure, even for very young or elderly patients. Three types of autologous collections exist:
Collection of autologous blood prior to surgery peaked in 1992 at 8% of the United States blood supply and declined to 2.5% in 2002. The decline has been largely attributed to the increasing safety of the volunteer allogeneic blood supply. Autologous collections have been used most successfully for orthopedic (joint replacement), vascular (aortic aneurysm repair), cardiothoracic (bypass), and urologic (radical prostatectomy) surgery. Autologous blood is also beneficial for the patient with alloantibodies to multiple high incidence antigens. Autologous blood should not be collected for surgical or obstetrical procedures, which seldom require transfusion. The ideal patient for autologous donation is one who:
Some individuals may not be good candidates for autologous donation. Patients taking antihypertensive medications such as beta-blockers may not be able to maintain blood pressure following multiple donations. Autologous blood donation by pregnant women is beneficial only in selected cases such as alloantibodies to multiple or high-incidence antigens, placenta previa, high-risk pregnancy, and bleeding disorders. Patients with severe aortic stenosis, unstable angina, recent myocardial infarction, cyanotic heart disease, cerebrovascular accident, uncontrolled hypertension, active seizure disorder, and bacteremia are usually considered at too high a risk for autologous donation. In addition to general information about blood donation, autologous donors need information about additional fees charged for autologous services. Because preoperative autologous units require special handling and tracking, most facilities charge an additional autologous fee. Many of these additional charges are not covered by health insurance and are billed to the patient. Medicare covers autologous donation, but some major health insurers do not. Patients also need to be informed that they are responsible for charges even if the unit is not used. As soon as the surgery date has been scheduled, the attending physician prescribes the number of units to be donated. The patient's physician should request autologous blood collection in writing and the collection site should retain the written order. Requests should include patient's name, the number of units, component, anticipated surgical date, surgical procedure, and the physician's signature. In order for an autologous program to be effective, a sufficient number of units should be drawn from these patients to minimize the possibility of exposure to allogeneic blood. The underlying principles of autologous blood donation are that red blood cells are donated before elective surgery and sufficient time is allowed for the bone marrow to regenerate all of the donated red cell mass, thereby providing additional red cell volume at the time of surgery. In order to insure that autologous donation is beneficial the following recommendations should be considered:
Each unit of blood donated decreases a patient's hemoglobin by 1g/dL. When a donation is made 2 to 3 weeks before surgery, less than one fourth of the blood loss is regenerated. In order to maximize the benefit of autologous transfusions, sufficient time must be allowed for regenerative erythropoiesis to occur. If not, autologous donation may decrease the patient's preoperative hemoglobin level and place them at higher risk of leaving the hospital more anemic than if they had not donated. Alternatively, the patient may require an allogeneic transfusion. Iron therapy should be started immediately. Ideally, the requesting physician prescribes supplemental iron even before the first donation to allow maximum time for iron intake. Iron deficiency is frequently the limiting factor for individuals seeking to donate multiple units of blood. All autologous units must be tested for ABO and Rh. If a unit is to be transfused at a facility other than the collecting facility, it must be tested for all disease markers required by FDA including HBsAg, anti-HIV, and anti-HCV. If the donor tests repeatedly reactive for any marker, a biohazard label is placed on all his/her autologous units. Testing and acceptability policies vary with institution: some discard units that test as confirmed positive for HIV or HBsAg to prevent staff or other patients from accidentally being exposed to the unit. Red cell units are collected with Adsol and can be stored for 42 days. Effective May 10, 2004, Community Blood Center began leukocyte reduction of all RBC units prepared from autologous and directed donors. Some blood centers have recently adopted the policy of collecting two units during a single visit by apheresis. It is more expensive, but is more convenient. Indications for transfusion of autologous units are similar to allogeneic transfusions, and autologous units should not be transfused indiscriminately to an asymptomatic patient merely because it is available. Although autologous blood is the safest form of blood transfusion, adverse reactions can occur. Any transfusion may result in fluid overload. Clerical identification errors can occur, leading to the transfusion of incompatible blood to one and maybe two patients. Bacterial contamination can lead to septic shock. Hemodilution Some anesthesiologists hemodilute their patients immediately before surgery. While preparing a patient for surgery, they may withdraw 1 to 2 units of fresh whole blood and replace this volume with IV fluids. The units of blood must be labeled properly and stored at room temperature. They must be reinfused to the patient within 8 hours after collection to prevent deterioration of platelets and coagulation factors. No additional testing is necessary. This protocol reduces the need to use someone else's blood for transfusion. It also reduces the total red cell mass lost during surgery since the blood is diluted with IV fluids. However, only a limited number of units can be collected this way and not all patients can tolerate such changes in blood volume. Intra-operative Autologous Blood Collection Intra-operative collection involves the aspiration, filtration, and reinfusion of shed blood from a clean surgical site or from an extra corporeal circuit. The equipment used for this type of blood salvage varies and may include a wash cycle to remove plasma, activated coagulation factors, and hemolyzed red cells. Any of the following may be an indication for intraoperative collection:
Certain criteria must be met including:
Post-operative Autologous Blood Collection Shed blood can only be transfused to the patient from which it was collected and procedures must ensure proper identification of the unit to the patient. The unit must be labeled with the patient's name, identification number, date and time of collection, expiration date and the statement "For Autologous Use Only". If it is stored in the Blood Bank, it must be handled like any other autologous unit except that disease testing may be waived. The unit should be stored at room temperature for up to 6 hours or at 1 to 6o C for up to 24 hours if storage begins within 4 hours of collection. Directed Blood Donations Directed donations are units of blood directly solicited from family or friends by the intended recipient. Some patients anticipating elective surgery prefer to receive blood donated by relatives or friends, even though directed donations have not been proven to be safer than those from the community blood supply. Laws in many states have been established which protect the patient's right to solicit direct donation. Direct donation should be available for non-emergent transfusions. Physicians initiate the order for directed donation of blood at a patient's request. The order must specify the number of units needed, the transfusion date(s), and the patient's ABO and Rh type. The patient should instruct his/her directed donors to donate a few days to a few weeks before the anticipated transfusion to allow adequate time for donor scheduling, blood collection, test completion, and shipping. Directed donors must have a blood type that is compatible with the recipient and meet the same donor requirements as volunteer donors. The same tests are performed on directed units as volunteer units. Generally, donors give blood only once every 8 weeks. To reduce the number of donors a patient is exposed to, special arrangements can be made to have some designated donors give more frequently. These frequent donors must continue to meet all other donor requirements each time they donate. Specific directed donor policies vary with institution. Only acceptable, ABO and Rh compatible directed donor units are reserved for a patient. Units that are ABO and Rh incompatible are either not drawn or released to general stock. Most facilities reserve directed donor units only for a specified time, such as 5 days after the scheduled transfusion date or 1 week before the unit expires. After this time, they may be released to general stock and used on someone else to prevent unnecessary waste, although some institutions will not use them for other patients because of concerns that a directed donation may not be as safe as a volunteer non-directed donation. If the anticipated transfusion date changes, the physician should notify the Blood Bank immediately so that the reservation time is extended. Directed donor units are not routinely frozen to extend storage. Instead, additional donors are recruited. Because directed donor units require extra handling and tracking, they usually cost more than regular volunteer units. These charges are billed whether or not the unit is transfused. Directed donations, like autologous units, may not be covered by health insurance reimbursement. Patients seeking directed donation should be informed of this possibility. Indications for Directed Donation include:
Apheresis Apheresis employs an automated cell separator that harvests a specific blood component by centrifugal force. It involves a multi-step process that includes:
Red cells may be collected by apheresis. Two allogeneic or autologous red cell units may be removed every 16 weeks. Volume depletion is minimized with saline infusion and the procedure is limited to individuals who are larger and have higher hematocrits (>40%) than current minimum standards for whole blood donors. Plasmapheresis involves the separation of fresh plasma from 1 to 1.2 L of whole blood from a single donor, depending on the donor's weight. This component is usually processed into Fresh Frozen Plasma or Cryoprecipitate. Its larger volume (usually equivalent to 2 units FFP) can be used by one patient to reduce donor exposures or can be aliquoted to benefit several patients. Plateletpheresis is the collection of platelets from a single donor and is often called single donor platelets. Donors should not take aspirin within 36 hours of donation. Blood pumped from one arm passes through a blood cell separator centrifugation system that collects platelets and returns plasma and red cells to the donor's other arm. Between 4000 and 5000 mL of blood are processed over 1.5 to 2 hours. A single donor platelet concentrate contains >3.0 X 1011 platelets suspended in approximately 200 mL of plasma, which is the equivalent of 6 to 8 random donor platelet concentrates. They can be stored up to 5 days at room temperature. Because red cells and plasma are returned, a plateletpheresis donor can give more frequently than a whole blood donor; once or twice a week. This procedure is ideal for collecting platelets from special donors such as directed donor, platelet crossmatch compatible or HLA-matched. Single donor apheresis platelets contain fewer than 5 x 106 white blood cells and are considered to be leukocyte reduced. Additional leukocyte reduction filtration is not necessary. Rh negative patients do not need Rh immune globulin after transfusion of Rh positive apheresis platelets because they contain so few red blood cells. Granulocyte concentrates are prepared from a single donor by centrifugal leukapheresis. Each unit contains 1 to 5 X 1010 granulocytes, 0.2 to 1.5 X 1010 lymphocytes, 1 to 10 X 1011 platelets, and 25 to 50 mL of red blood cells suspended in 200 to 500 mL of plasma. Units collected from donors stimulated with G-CSF have granulocyte concentrations at the upper range. Granulocytes need to be transfused as soon as possible following collection to maintain their chemotactic and phagocytic function. Granulocyte transfusions are ineffective if more than 24 hours have elapsed since collection. Units must be ABO and Rh compatible and should be irradiated prior to transfusion. They shouldt be transfused through a standard blood infusion set with a 170 - 260 micron filter. Microaggregate and leukocyte reduction filters shoud not be used. |
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