Why did success elude experimenters for so long? Clotting was the principal obstacle to overcome. Attempts to find a nontoxic anticoagulant began in , when Braxton Hicks recommended sodium phosphate. This was perhaps the first example of blood preservation research. Karl Landsteiner in discovered the ABO blood groups and explained the serious reactions that occur in humans as a result of incompatible transfusions. His work early in the 20th century won a Nobel Prize.
Next came devices designed for performing the transfusions. Edward E. Lindemann was the first to succeed. He carried out vein-to-vein transfusion of blood by using multiple syringes and a special cannula for puncturing the vein through the skin. However, this time-consuming, complicated procedure required many skilled assistants. It was not until Unger designed his syringe-valve apparatus that transfusions from donor to patient by an unassisted physician became practical.
An unprecedented accomplishment in blood transfusion was achieved in , when Hustin reported the use of sodium citrate as an anticoagulant solution for transfusions. Later, in , Lewisohn determined the minimum amount of citrate needed for anticoagulation and demonstrated its nontoxicity in small amounts.
Transfusions became more practical and safer for the patient. The development of preservative solutions to enhance the metabolism of the RBC followed. Glucose was tried as early as , when Rous and Turner introduced a citrate-dextrose solution for the preservation of blood. However, the function of glucose in RBC metabolism was not understood until the s.
Therefore, the common practice of using glucose in the preservative solution was delayed. World War II stimulated blood preservation research because the demand for blood and plasma increased. The pioneer work of Dr. Charles Drew during World War II on developing techniques in blood transfusion and blood preservation led to the establishment of a widespread system of blood banks.
In February , Dr. Drew established became the model for the national volunteer blood donor program of the American Red Cross. Efforts in several countries resulted in the landmark publication of the July issue of the Journal of Clinical Investigation, which devoted nearly a dozen papers to blood preservation.
Hospitals responded immediately, and in , blood banks were established in many major cities of the United States; subsequently, transfusion became commonplace. The daily occurrence of transfusions led to the discovery of numerous blood group systems. Antibody identification surged to the forefront as sophisticated techniques were developed.
Frequent transfusions and the massive use of blood soon resulted in new problems, such as circulatory overload. Component therapy has solved these problems. Before, a single unit of whole blood could serve only one patient. With component therapy, however, one unit may be used for multiple transfusions.
Physicians can transfuse only the required fraction in the concentrated form, without overloading the circulation. Extensive use of blood during this period, coupled with component separation, led to increased comprehension of erythrocyte metabolism and a new awareness of the problems associated with RBC storage. Volunteer donors are not 3 paid and provide nearly all of the blood used for transfusion in the United States.
This has provided a small increase in the various components. Modified plastic collection systems are used when collecting mL of blood, with the volume of anticoagulant-preservative solution being increased from 63 mL to 70 mL.
For a pound donor, a maximum volume of mL can be collected, including samples drawn for processing. A volunteer donor can donate whole blood every 8 weeks. Units of the whole blood collected can be separated into three components: packed RBCs, platelets, and plasma.
In recent years, less whole blood has been used to prepare platelets with the increased utilization of apheresis platelets. Hence, many units are converted only into RBCs and plasma. The plasma can be converted by cryoprecipitation to a clotting factor concentrate that is rich in antihemophilic factor AHF, factor VIII; refer to Chapter A unit of whole blood—prepared RBCs may be stored for 21 to 42 days, depending on the anticoagulant-preservative solution used when the whole blood unit was collected, and whether a preserving solution is added to the separated RBCs.
Although most people assume that donated blood is free because most blood-collecting organizations are nonprofit, a fee is still charged for each unit to cover the costs associated with collecting, storing, testing, and transfusing blood. The donation process consists of three steps or processes Box 1—1 : 1. Educational reading materials 2. The donor health history questionnaire 3. Step 2: The Donor Health History Questionnaire A uniform donor history questionnaire, designed to ask questions that protect the health of both the donor and the recipient, is given to every donor.
The health history questionnaire is used to identify donors who have been exposed to diseases that can be transmitted in blood e. Step 3: The Abbreviated Physical Examination The abbreviated physical examination for donors includes blood pressure, pulse, and temperature readings; hemoglobin or hematocrit level; and the inspection of the arms for skin lesions.
For a more detailed description of donor screening and processing, refer to Chapter Currently, 10 screening tests for infectious disease are performed on each unit of donated blood Table 1—1. The current risk of transfusion-transmitted hepatitis C virus HCV is 1 in 1,,, and for hepatitis B virus HBV , it is between 1 in , and 1 in ,, respectively. Normal chemical composition and structure of the RBC membrane 2. Hemoglobin structure and function 3.
RBC metabolism Defects in any or all of these areas will result in RBCs surviving less than the normal days in circulation. Proteins that extend from the outer surface and span the entire membrane to the inner cytoplasmic side of the RBC are termed integral membrane proteins. Beneath the lipid bilayer, a second class of membrane proteins, called peripheral proteins, is located and limited to the cytoplasmic surface of the membrane forming the RBC cytoskeleton.
Lipids are not equally distributed in the two layers of the membrane. The external layer is rich in glycolipids and choline phospholipids. In addition, they maintain a critical role in two important RBC characteristics: deformability and permeability. Deformability To remain viable, normal RBCs must also remain flexible, deformable, and permeable. The loss of adenosine triphosphate ATP energy levels leads to a decrease in the phosphorylation of spectrin and, in turn, a loss of membrane deformability.
The survival of these forms is also shortened. Any abnormality that increases permeability or alters cationic transport may decrease RBC survival. Schematic illustration of red blood cell membrane depicting the composition and arrangement of RBC membrane proteins. Numbers refer to pattern of migration of SDS sodium dodecyl sulfate polyacrylamide gel pattern stained with Coomassie brilliant blue. Relations of protein to each other and to lipids are purely hypothetical; however, the positions of the proteins relative to the inside or outside of the lipid bilayer are accurate.
Note: Proteins are not drawn to scale and many minor proteins are omitted. Figure 1—2. Chloride Cl— and bicarbonate HCO3— can traverse the membrane in less than a second.
It is speculated that this massive exchange of ions occurs through a large number of exchange channels located in the RBC membrane.
RBC volume and water homeostasis are maintained by controlling the intracellular concentrations of sodium and potassium. Because the mature erythrocyte has no nucleus and there is no mitochondrial apparatus for oxidative metabolism, energy must be generated almost exclusively through the breakdown of glucose. All of these processes are essential if the erythrocyte is to transport oxygen and to maintain critical physical characteristics for its survival. The methemoglobin reductase pathway is another important pathway of RBC metabolism, and a defect can affect RBC post-transfusion survival and function.
The amount of 2,3-DPG found within RBCs has a significant effect on the affinity of hemoglobin for oxygen and therefore affects how well RBCs function post-transfusion. The resulting conformation of the deoxyhemoglobin molecule is known as the tense T form, which has a lower affinity for oxygen. This is the relaxed R form of the hemoglobin molecule, which has a higher affinity for oxygen. These allosteric changes that occur as the hemoglobin loads and unloads oxygen are referred to as the respiratory movement.
Red cell metabolism. The shape of this curve is very important physiologically because it permits a considerable amount of oxygen to be delivered to the tissues with a small drop in oxygen tension. This is the normal situation of oxygen delivery at a basal metabolic rate. Of these three ligands, 2,3-DPG plays the most important physiological role. In situations such as hypoxia, a compensatory shift to the right of the hemoglobin-oxygen dissociation curve alleviates the tissue oxygen deficit.
A shift to the left of the hemoglobin-oxygen dissociation curve results, conversely, in an increase in hemoglobinoxygen affinity and a decrease in oxygen delivery to the tissues. Multiple transfusions of 2,3-DPG— depleted stored blood can shift the oxygen dissociation curve to the left. Because blood must be stored from the time of donation until the time of transfusion, the viability of RBCs must be maintained during the storage time as well.
To determine post-transfusion RBC survival, RBCs are taken from healthy subjects, stored, and then labeled with radioisotopes, reinfused to the original donor, and measured 24 hours after transfusion. The loss of RBC viability has been correlated with the lesion of storage, which is associated with various biochemical changes Table 1—2.
Hemoglobin-oxygen dissociation curve. It is well accepted, however, that 2,3-DPG is re-formed in stored RBCs, after in vivo circulation, resulting in restored oxygen delivery. The rate of restoration of 2,3-DPG is influenced by the acid-base status of the recipient, the phosphorus metabolism, the degree of anemia, and the overall severity of the disorder. The addition of various chemicals, along with the approved anticoagulant-preservative CPD, was incorporated in an attempt to stimulate glycolysis so that ATP levels were better maintained.
CPDA-1 contains 0. Table 1—4 lists the various chemicals used in anticoagulant solutions and their functions during the storage of red cells. This is a complex mechanism with numerous variables involved that are beyond the scope of this text.
Stored RBCs do regain the ability to synthesize 2,3-DPG after transfusion, but levels necessary for optimal hemoglobin oxygen delivery are not reached immediately. Approximately 24 hours are required to restore normal levels of 2,3-DPG after transfusion.
However, evidence suggests that, in the transfused subject whose capacity is limited by an underlying physiological disturbance, even a brief period of altered oxygen hemoglobin affinity is of great significance. Studies demonstrate that myocardial function improves following transfusion of blood with high 2,3-DPG levels during cardiovascular surgery.
It is apparent that many factors may limit the viability of transfused RBCs. One of these factors is the plastic material used for the storage container. The plastic must be sufficiently permeable to CO2 in order to maintain higher pH levels during storage. Glass storage containers are a matter of history in the United States. Currently, the majority of blood is stored in polyvinyl chloride PVC plastic bags.
One issue associated with PVC bags relates to the plasticizer di ethylhexyl -phthalate DEHP , which is used in the manufacture of the bags. It has been found to leach from the plastic into the lipids of the plasma medium and RBC membranes of the blood during storage.
However, its use or that of alternative plasticizers that leach are important because they have been shown to stabilize the RBC membrane and therefore reduce the extent of hemolysis during storage.
Another issue with PVC is its tendency to break at low temperatures; therefore, components frozen in PVC bags must be handled with care. In addition to PVC, polyolefin containers, which do not contain DEHP, are available for some components, and latex-free plastic containers are available for recipients with latex allergies. Additive solutions are now widely used. One of the reasons for their development is that removal of the plasma component during the preparation of RBC concentrates removed much of the nutrients needed to maintain RBCs during storage.
This was dramatically observed when high-hematocrit RBCs were prepared. The influence of removing substantial amounts of adenine and glucose present originally in, for example, the CPDA-1 anticoagulant-preservative solution led to a decrease in viability, particularly in the last 2 weeks of storage. Additive solutions mL to the RBC concentrate prepared from a mL blood collection also overcome this problem.
The ability to pack RBCs to fairly high hematocrits before adding additive solution, also provides a means to harvest greater amounts of plasma with or without platelets. Box 1—2 summarizes the benefits of RBC additive solutions. Currently, three additive solutions are licensed in the United States: 1.
Adsol AS-1; Baxter Healthcare 2. Nutricel AS-3; Pall Corporation 3. Optisol AS-5; Terumo Corporation The additive solution is contained in a satellite bag and is added to the RBCs after most of the plasma has been expressed. All three additives contain saline, adenine, and glucose. AS-1 and AS-5 also contain mannitol, which protects against storage-related hemolysis,23 while AS-3 contains citrate and phosphate for the same purpose.
All of the additive solutions are approved for 42 days of storage for packed RBCs. Table 1—5 lists the currently approved additive solutions. Advanced Concepts Table 1—6 shows the biochemical characteristics of RBCs stored in the three additive solutions after 42 days of storage. Blood stored in additive solutions is now routinely given to newborn infants and pediatric patients,26 although some clinicians still prefer CPDA-1 RBCs because of their concerns about one or more of the constituents in the additive solutions.
None of the additive solutions maintain 2,3-DPG throughout the storage time. The procedure for freezing a unit of packed RBCs is not complicated.
Basically, it involves the addition of a cryoprotective agent to RBCs that are less than 6 days old. Glycerol is used most commonly and is added to the RBCs slowly with vigorous shaking, thereby enabling the glycerol to permeate the RBCs. The cells are then rapidly frozen and stored in a freezer. Table 1—7 lists the advantages of the high-concentration glycerol technique in comparison with the low-concentration glycerol technique.
See Chapter 13 for a detailed description of the RBC freezing procedure. Currently, the FDA licenses frozen RBCs for a period of 10 years from the date of freezing; that is, frozen RBCs may be stored up to 10 years before thawing and transfusion.
Once thawed, these RBCs demonstrate function and viability near those of fresh blood. Experience has shown that year storage periods do not adversely affect viability and function. Advanced Concepts Transfusion of frozen cells must be preceded by a deglycerolization process; otherwise the thawed cells would be accompanied by hypertonic glycerol when infused, and RBC lysis would result.
Need to control freezing rate No Yes 3. Type of freezer Mechanical Liquid nitrogen 4. Shipping requirements Dry ice Liquid nitrogen 6. Effect of changes in storage temperature Can be thawed and refrozen Critical concentrations of saline. Excessive hemolysis is monitored by noting the hemoglobin concentration of the wash supernatant. Osmolality of the unit should also be monitored to ensure adequate deglycerolization. Recently, an instrument ACP , Haemonetics has been developed that allows the glycerolization and deglycerolization processes to be performed under closed system conditions.
The deglycerolized cells, prepared using salt solutions as in the traditional procedures, are suspended in the AS-3 additive solution as a final step, which is thought to stabilize the thawed RBCs. These storage conditions are based on the parameters used in a study by Valeri and others that showed that RBC properties were satisfactorily maintained during a day period.
It contains phosphate, inosine, pyruvate, and adenine. RBCs stored in the liquid state can be rejuvenated at outdate or up to 3 days after outdate, depending on RBC preservative solutions used. Currently, only RBCs prepared from mL collections can be rejuvenated. Following rejuvenation, the RBCs can be washed to remove the rejuvenation solution and transfused within 24 hours. More commonly, they are frozen, then washed in the postfreezing deglycerolization process.
Because the process is currently accomplished with an open system, federal regulations require that rejuvenated or frozen RBCs are used within 24 hours of thawing. The rejuvenation process is expensive and timeconsuming; therefore, it is not used often but is invaluable for preserving selected autologous and rare units of blood for later use.
Development of improved additive solutions 2. Development of procedures to reduce and inactivate the level of pathogens that may be in RBC units 3. Development of methods to produce RBCs through bioengineering blood pharming 5. Procedures to Reduce and Inactivate Pathogens Research is being conducted to develop procedures that would reduce the level of or inactivate residual viruses, bacteria, and parasites in RBC units. One objective is to develop robust procedures that could possibly inactivate unrecognized unknown pathogens that may be present, such as the viruses that have emerged in recent years.
Although methods to inactivate pathogens in plasma have been used successfully for more than 20 years, pathogen reduction of cellular components has proven more challenging. The use of enzymes that remove the carbohydrate moieties of the A and B antigens is the mechanism for forming O-type RBCs. The enzymes are removed by washing after completion of the reaction time.
More recently, cultured RBCs generated from in vitro HSC has been reported that survive in circulation for several weeks. In the s, safety concerns about HIV led to renewed interest in finding a substitute for human blood, and more recently, the need for blood on remote battlefields has heightened that interest.
The U. Today the search continues for a safe and effective oxygen carrier that could eliminate many of the problems associated with blood transfusion, such as the need for refrigeration, limited shelf-life, compatibility, immunogenicity, transmission of infectious agents, and shortages. Box 1—3 lists the potential benefits of artificial oxygen carriers. Safety and efficacy must be demonstrated through clinical trials.
Table 1—9 outlines the different phases of testing. Recently the terms oxygen therapeutics and artificial oxygen carriers AOC have been used to describe the broad clinical applications envisioned for these products.
Originally developed to be used in trauma situations such as accidents, combat, and surgery, RBC substitutes have, until now, fallen short of meeting requirements for these applications. Despite years of research, RBC substitutes are still not in routine use today. None have received FDA approval for clinical use in the United States, although specific products have been given to individual patients under compassionate use guidelines.
Hemoglobin-Based Oxygen Carriers By , it was established that purified hemoglobin could restore blood volume and deliver oxygen; however, its transfusion resulted in serious side effects, such as vasoconstriction and renal failure.
This toxicity was thought to be due to stromal remnants in the hemoglobin solutions. Phase II The drug is given to a larger group of people to to see if it is effective and to further evaluate its safety.
Phase III The drug is given to large groups of people 1, to 3, to confirm its effectiveness, monitor side effects, compare it to commonly used treatments, and collect information that will allow the drug to be used safely. Cross-linking, polymerization, and pegylation produced larger, more stable molecules. This reduced some, but not all, of the adverse effects.
To date, four generations of HBOCs have been developed. Bovine hemoglobin has several advantages over human hemoglobin. It has a lower oxygen affinity and better oxygen uploading in ischemic tissues, and its availability is not dependent upon an adequate supply of outdated human RBCs.
However, concerns about potential immunogenicity and transmission of prions have been raised. Development of several products was terminated following clinical trials in which serious adverse side effects were discovered. Hemopure was approved for clinical use in South Africa in and a related product, Oxyglobin, has been used to treat canine anemia in the United States and Europe since An interesting side note is that a Spanish cyclist admitted to using Oxyglobin in the Tour de France.
He crashed after experiencing nausea. Table 1—10 summarizes the history and status of several HBOCs. Perfluorocarbons Perfluorocarbons PFCs are synthetic hydrocarbon structures in which all the hydrogen atoms have been replaced with fluorine. They are chemically inert, are excellent gas solvents, and carry O2 and CO2 by dissolving them. Because of their small size about 0. Fluosol Green Cross Corp. Four other PFCs have proceeded to clinical trials. One, Perftoran Perftoran , is in clinical use in Russia and Mexico.
Two others are no longer under development, and one Oxycyte, Oxygen Biotherapeutics is currently being investigated as an oxygen therapeutic for treatment of wounds, decompression sickness, and traumatic brain injury. Table 1—13 for the advantages and disadvantages of Perfluorochemicals.
Removed from production because of increased mortality rates. Did not obtain FDA approval. No longer produced. Approved for use in S. Africa Oxy Oxygenix Liposome-encapsulated hemoglobin In experimental phase.
Platelets are cellular fragments derived from the cytoplasm of megakaryocytes present in the bone marrow. They do not contain a nucleus, although the mitochondria contain DNA. Platelets have specific roles in the hemostatic process that are critically dependent on an adequate number in the circulation and on normal platelet function. Normal platelet function in vivo requires more than , platelets per microliter. Spontaneous hemorrhage may occur when the platelet count falls below 10, Platelet plug formation involves the adhesion of platelets to the subendothelium and subsequent aggregation, with thrombin being a key effector of these phenomena.
Platelets, like other cells, require energy in the form of ATP for cellular movement, active transport of molecules across the membrane, biosynthetic purposes, and maintenance of a hemostatic steady state. Advanced Concepts The organelle region of the platelet is responsible for the metabolic activities in this cell. Like many other cells, platelets possess mitochondria and various cytoplasmic granules. Platelets, however, are anucleated and do not possess either a Golgi body or rough endoplasmic reticulum RER.
Generally, the most numerous organelles are the platelet granules. Approved in ; discontinued in because of clinical shortcomings and poor sales. Development stopped due to lack of funding. Oxyfluor HemaGen Early phase clinical trials completed.
Development stopped due to loss of financial backing. Currently in phase II trials in Switzerland for treatment of traumatic brain injury. Perftoran Perftoran Approved for use in Russia and Mexico. Glycogen granules are also found within the organelle zone and function in platelet metabolism. The estimated 10 to 60 mitochondria present per platelet require glycogen as their source of energy for metabolism. The Platelet Storage Lesion Basic Concepts Platelet storage still presents one of the major challenges to the blood bank because of the limitations of storing platelets.
During storage, a varying degree of platelet activation occurs that results in release of some intracellular granules and a decline in ATP and ADP.
This platelet activation often results in temporary aggregation of platelets into large sheets that must be allowed to rest for the aggregation to be reversed, especially when the platelet concentrates PCs are prepared with the plateletrich-plasma PRP method.
The reduced oxygen tension pO2 in the plastic platelet storage container results in the platelets increasing the rate of glycolysis to compensate for the decrease in ATP regeneration from the oxidative TCA metabolism.
This increases glucose consumption and causes an increase in lactic acid that must be buffered. This results in a fall in pH. During the storage of PCs in plasma, the principal buffer is bicarbonate. When the bicarbonate buffers are depleted during PC storage, the pH rapidly falls to less than 6. In addition, when pH falls below 6. The 15 platelets then become irreversibly swollen, aggregate together, or lyse, and when infused, will not circulate or function. During storage of PCs, the pH will remain stable as long as the production of lactic acid does not exceed the buffering capacity of the plasma or other storage solution.
Advanced Concepts The platelet storage lesion results in a loss of platelet quality and viability. When platelets deteriorate during storage, their membranes lose their ability to maintain normal lipid asymmetry and phosphatidylserine becomes expressed on the outer membrane surface.
Generally, the quality-control measurements required by various accreditation organizations for platelet concentrates include platelet concentrate volume, platelet count, pH of the unit, and residual leukocyte count if claims of leukoreduction are made.
Box 1—4 lists the in vitro platelet assays that have been correlated with in vivo survival. Clinical Use of Platelets Platelet components are effectively used to treat bleeding associated with thrombocytopenia, a marked decrease in platelet number.
The efficacy of the transfused platelet concentrates is usually estimated from the corrected count increment CCI of platelets measured after transfusion. It should be noted that the CCI does not evaluate or assess function of the transfused platelets. Platelets are also utilized in some instances to treat other disorders in which platelets are qualitatively or quantitatively defective because of genetic reasons. In the s and s, platelet transfusions were given as freshly drawn whole blood or platelet-rich plasma.
Circulatory overload quickly developed as a major complication of this method of administering platelets. Since the s, platelets have been prepared from whole blood as concentrates in which the volume per unit is near 50 mL in contrast to the to mL volume of platelet-rich plasma units. Today, platelets are prepared as concentrates from whole blood and increasingly by apheresis. Platelets still remain as the primary means of treating thrombocytopenia, even though therapeutic responsiveness varies according to patient conditions and undefined consequences of platelet storage conditions.
FDA standards define the expiration time as midnight of day 5. Primarily flatbed and circular agitators are in use. There are a number of containers in use for 5-day storage of WBD and apheresis platelets.
History of Platelet Storage: Rationale for Current Conditions Advanced Concepts The conditions utilized to store platelets have evolved since the s as key parameters that influence the retention of platelet properties. This structural change is considered to be the factor responsible for the deleterious effects of cold storage. This loss of shape is probably a result of microtubule disassembly. Based on many follow-up studies, platelets are currently stored at room temperature.
These studies provided an understanding of the factors that influenced the retention of platelet viability and the parameters that needed to be considered to optimize storage conditions. One factor identified as necessary was the need to agitate platelet components during storage, although initially the rationale for agitation was not understood.
The positive role for oxygen has been associated with the maintenance of platelet component pH. Although storage itself was associated with a small reduction in post-infusion platelet viability, an enhanced loss was observed when the pH was reduced from initial levels of near 7 to the range of 6.
The standard was subsequently changed to 6. As pH was reduced from 6. This change is irreversible when the pH falls to less than 6. This limited the storage period to 3 days. The containers being used for storage were identified as being responsible for the fall in pH because of their limiting gas transfer properties for oxygen and carbon dioxide.
Carbon dioxide buildup from aerobic respiration and as the end product of plasma bicarbonate depletion also influenced the fall in pH.
The gas transport properties of a container are known to reflect the container material, the gas permeability of the wall of the plastic container, the surface area of the container available for gas exchange, and the thickness of the container. Insufficient agitation may also be a factor responsible for pH reduction because agitation facilitates gas transport into the containers.
Storage in Second-Generation Containers Understanding the factors that led to the reduction in pH in first-generation platelet containers resulted in the development of second-generation containers, starting around The second-generation containers, with increased gas transport properties allowing increased oxygen transport and carbon dioxide escape , are available and are being utilized for storing platelets for 5 days without pH substantially falling.
The second-generation containers are constructed in some cases with PVC and in other cases with polyolefin plastic. For most PVC containers, alternative plasticizers trimellitate and citrate based have been used to increase gas transport.
The nominal volumes of the containers are to mL and 1 to 1. The size of the containers for apheresis components reflects the increased number of platelets that are being stored and hence the need for a larger surface area to provide adequate gas transport properties for maintaining pH levels near the initial level of 7 even after 5 days of storage.
Box 1—5 lists factors that should be considered when using 5-day platelet storage containers. Storing Platelets Without Agitation for Limited Times Although platelet components should be stored with continuous agitation, there are data that suggest that platelet properties, based on in vitro studies, are retained when agitation is discontinued for up to 24 hours during a 5-day storage period.
Measurement of Viability and Functional Properties of Stored Platelets Viability indicates the capacity of platelets to circulate after infusion without premature removal or destruction. Platelets have a life span of 8 to 10 days after release from megakaryocytes. Storage causes a reduction in this parameter, even when pH is maintained.
The observation of the swirling phenomenon caused by discoid platelets when placed in front of a light source has been used to obtain a semiqualitative evaluation of the retention of platelet viability properties in stored units.
Clinical assessment of hemostasis is being increasingly used. There is also the issue of retaining platelet function during storage. Historically, room temperature storage has been thought to be associated with a reduction in platelet functional properties. However, the vast transfusion experience with room temperature platelets worldwide indicates that such platelets have satisfactory function. As has been suggested many times over the last 30 years, it is possible that room temperature—stored platelets undergo a rejuvenation of the processes that provide for satisfactory function upon introduction into the circulation.
Activation is a prerequisite for platelet function in hemostasis. During storage, it takes different forms.
There are some data that suggest that specific inhibitors of the activation processes may have a beneficial influence during storage. It should be noted that except for change in pH, the effect of in vitro changes on post-transfusion platelet survival and function is unknown, and some of the changes may be reversible upon transfusion.
Room temperature storage and the presence of oxygen provide a good environment for bacterial proliferation. As the level of bacteria in the platelets at the time of collection can be low, samples are not taken until after at least 24 hours of storage. This provides time for any bacteria present to replicate to detectable levels.
The eBDS system measures the oxygen content of the air within the sample pouch following incubation for 18 to 30 hours. A decrease in oxygen level indicates the presence of bacteria. With both culture systems, the need to delay sampling and the requirement for incubation delay entry of the platelet products into inventory.
Box 1—6 lists the disadvantages associated with the use of culture methods for the detection of bacterial contamination of platelets. The third bacterial detection method approved by the FDA, Scansystem, is a laser-based, scanning cytometry method. This practice made it difficult for some blood banks to meet the demand for apheresis platelets, and WBD platelets became underutilized.
The PDG test, which was previously approved by the FDA for testing leukocyte-reduced platelets as an adjunct to culture, is an immunoassay that detects lipoteichoic acids on grampositive bacteria and lipopolysaccharides on gram-negative bacteria. Both aerobes and anaerobes are detected.
The test can be performed on pools of up to 6 units of WBD platelets. Following pretreatment, the sample is loaded into a disposable plastic cartridge with built-in controls that turn from yellow to blue-violet when the test is ready to be read, in approximately 20 minutes. A pink-colored bar in either the grampositive or gram-negative test window indicates a positive result. The manufacturer states that the system has a specificity of The optimum time for sampling is at least 72 hours after collection.
The practice of screening platelets for bacterial contamination has reduced, but not eliminated, the transfusion of contaminated platelet products. False-negative cultures can occur when bacteria are present in low numbers and when the pathogen is a slow-growing organism. The American Red Cross received reports of 20 septic transfusion reactions from to following transfusion of culturenegative platelets. Eighty percent of the septic reactions were due to Staphylococcus spp.
Three of these reactions were fatal, for a fatality rate of 1 per , distributed products. Another more recent precaution is the diversion of the first aliquot about 20 to 30 mL of collected blood into a separate but connected diversion pouch. This procedure minimizes the placement of skin plugs, the most common source of bacterial contamination, into the platelet products.
The retention of platelet properties during storage of pools has been shown in a number of studies. Traditionally, four to six WBD platelets are pooled into a single bag by the transfusion service just prior to issue.
This facilitates transfusion but reduces the shelf-life of the platelets to 4 hours, because they are prepared in an open system.
Acrodose platelets are pooled ABO-matched, leukoreduced WBD platelets that have been cultured and are ready for transfusion. Because they are produced in a closed system, they can be stored for 5 days from collection. They provide a therapeutic dose equivalent to apheresis platelets and at a lower cost,68 but they do expose the recipient to multiple donors.
A recent study comparing transfusion reactions from prestorage-pooled platelets, apheresis platelets, and poststorage-pooled WBD platelets found no difference in reaction rates among the different products. Development of methods that would allow platelets to be stored for 7 days 2. Development of additive solutions, also termed synthetic media 3. Development of procedures to reduce and inactivate the level of pathogens that may be in platelet units 4.
Development of platelet substitutes 5. Reports of septic transfusion reactions increased following this change, and in the storage time was changed back to 5 days.
Required Cookies These cookies allow you to explore OverDrive services and use our core features. Performance and reliability cookies These cookies allow us to monitor OverDrive's performance and reliability. Don't have an account? American Society for Clinical Pathology members Sign in via society site.
Sign in via your Institution Sign in. Purchase Subscription prices and ordering Short-term Access To purchase short term access, please sign in to your Oxford Academic account above. This article is also available for rental through DeepDyve. View Metrics. Email alerts Article activity alert. New issue alert. Receive exclusive offers and updates from Oxford Academic. Related articles in Google Scholar. Related articles in PubMed Quality improvement project: Reducing non-conformities of the samples for haemostasis testing in a secondary healthcare centre through the nurses' education in phlebotomy.
Citing articles via Google Scholar.Thank you for interesting in our services. We are a non-profit group that run this website to share documents. We need your help to maintenance this website. Please help us to share our service with your friends. Share Embed Donate. RBC only? Please refer to the appropriate chapter for more detailed information. Anti-E may often occur without obvious immune stimulation. Warm autoantibodies often appear to have anti-e-like specificity. Anti-Cw may often occur without obvious immune modern blood banking and transfusion practices pdf free download. Antibodies to V and VS present problems only in the black population, where modern blood banking and transfusion practices pdf free download antigen frequencies are in the order of 30 to Some antibodies to Kell system have been reported to react poorly in low poster design software free download full version media. Modern blood banking and transfusion practices pdf free download has been reported to occur following bacterial infection. Fya and Fyb antigens are destroyed by enzymes. Fy a—b— cells are resistant to invasion by P. FY3 and 5 are not destroyed by enzymes. FY5 may be formed by interaction of Rh and Duffy gene products. FY6 is a monoclonal antibody which reacts with most human red cells except Fy a—b— and is responsible for susceptibility of cells to penetration by P. Visit davisplus. Upon Adoption. Password-protected library of title-specific, online course content. Modern Blood Banking & Transfusion Practices SIXTH EDITION Blood Banking and Transfusion Medicine (Second Edition): Basic Principles and Practice. Read Modern Blood Banking & Transfusion Practices PDF - Ebook by Denise M. Harmening PhD MT (ASCP) ePUB ; Read Online Modern. Modern Blood Banking Transfusion Practices ebook DOWNLOAD PDF - MB. Share Embed Donate. Report this link. This book begins with a review of basic science and blood preservation, and continues to provide students with a working knowledge of modern blood banking. I didn't like this book that much, it was not helpful for my immunohematology class. The most disappointing thing is a lot of topics I tried to look up were not even. Buy Modern Blood Banking & Transfusion Practices: Read Kindle Store Reviews Print Replica; Due to its large file size, this book may take longer to download. Modern Blood Banking and Transfusion Practices Fifth Edition DENISE M. The author(s) and publisher have done everything possible to make this book. The 5th Edition continues to set the standard for developing a working knowledge of modern routine blood banking. Building from a review of the basic science. I found the book to be very readable and having some terms in bold print Modern. Blood Banking and Transfusion Practices. Second Edition. F.A. Davis Co. Currently, the FDA licenses frozen RBCs for a period of 10 years from the date of freezing; that is, frozen RBCs may be stored up to 10 years before thawing and transfusion. Thoroughly revised and updated, the 6th Edition of this popular text continues to set the standard for developing a comprehensive understanding of modern routine blood banking and transfusion practices. Glycerol is used most commonly and is added to the RBCs slowly with vigorous shaking, thereby enabling the glycerol to permeate the RBCs. Calmodulin, a cytoplas-mic calcium-binding protein, is speculated to control these pumps and to prevent excessive intracellular Ca2 buildup, which changes the shape and makes the RBC more rigid. Despite more than 30 years of research for acceptable RBC substitutes, an alternative to a unit of RBCs, even for specific clinical situations, is still not approved for human use. I highly recommend them. Approximately 24 hours are required to restore normal levels of 2,3-DPG after transfusion. Hospitals responded immediately, and in , blood banks were established in many major cities of the United States; subsequently, transfusion became com-monplace. Other ways include an increase in total car-diac output and an increase in the production of RBCs eryth-ropoiesis. Harmening has served on numerous national, statewide, and local committees and advisory boards. List the approved anticoagulant-preservative solutions and the maximum storage time for whole blood and RBCs in each preservative. Donor Screening and Component Preparation Covers the constantly changing approaches to stem cell transplantation and brings you the latest information on this controversial topic.