请输入您要查询的英文单词:

 

单词 transfusion reaction
释义

transfusion reaction


Thesaurus
Noun1.transfusion reaction - reaction of the body to a transfusion of blood that is not compatible with its own bloodtransfusion reaction - reaction of the body to a transfusion of blood that is not compatible with its own blood; an adverse reaction can range from fever and hives to renal failure and shock and deathresponse, reaction - a bodily process occurring due to the effect of some antecedent stimulus or agent; "a bad reaction to the medicine"; "his responses have slowed with age"
EncyclopediaSeetransfusion

transfusion reaction


transfusion

 [trans-fu´zhun] the introduction of whole blood or blood components directly into the blood stream. Among the elements transfused are packed red blood cells, plasma, platelets, granulocytes, and cryoprecipitate, a plasma protein rich in antihemophilic factor VIII. The current trend is to transfuse blood components rather than whole blood because by so doing the utility of each unit of blood can be extended and the treatment provided more nearly meets the specific needs of the patient.

Transfusion is most often indicated to maintain or replace blood volume, to provide deficient blood elements and improve coagulation, to maintain or improve transport of oxygen, and in exchange for blood that has been removed in the treatment of Rh incompatibility in the newborn, liver failure in which toxins accumulate in the blood, or in some other types of toxemia.Transfusion Methods. There are several different methods of transfusion. Direct transfusion, in which blood from one person is directly transferred to another person, is now rarely used. The usual method is indirect transfusion, in which blood is drawn from a donor, stored in a sterile container and later given to a recipient. Exchange transfusion, in which blood is removed from a person and simultaneously replaced by donor blood, is used mainly in treating erythroblastosis fetalis.Intrauterine or Fetal Transfusion. Intrauterine transfusion involves direct transfusion of Rh negative packed red blood cells into the fetal peritoneal cavity. It is done for the early treatment of pronounced degrees of fetal isoimmunization before weeks 32 to 34 of pregnancy.

The first step is injection of a radiopaque dye into the amniotic fluid. After the fetus ingests the dye, the intestinal tract can be visualized by radiographic techniques so that it serves as a guidepost for location of the abdominal cavity. A long pudendal needle is then inserted through the mother's abdomen and guided through the uterine wall, through the fetal abdomen, and into the peritoneal cavity. Another radiograph is taken to confirm correct placement of the needle and then the erythrocytes are transfused. The erythrocytes soon pass into the fetal blood stream. This procedure is obviously not without hazard and is done only if the fetus cannot be expected to survive without it. The treatment usually is done every 7 to 10 days until delivery. Once the newborn is delivered, transfusion" >exchange transfusion and supportive therapy are begun.
Blood Typing and Crossmatching. Transfusions were not practicable until the four main hereditary blood groups, A, B, AB, and O, were discovered at the beginning of the 20th century. Until these blood types were identified, antigen-antibody reactions could not be predicted and transfusion reactions (often fatal) were a matter of chance. There are certain antigens on the surface of red blood cells which can precipitate a transfusion reaction when incompatible blood types are mixed. In the ABO system the types are dictated by A antigen and B antigen. There is also an allele O that does not code for either A or B antigen. Thus there are four possible groups (A, B, AB, O). A person who is type A has only A antigen on red cells; one who is type B has only B antigen; one who is type AB has both A and B antigens; and one who is type O has neither. All individuals produce antibodies against the A or B antigens that are lacking on their own cells. Thus, type A has anti-B; type B has anti-A; type O has both; and type AB has neither.

Rh negative individuals lack D antigen on red cells. They do not produce anti-D antibodies unless they are directly exposed to Rh positive blood, as may occur from a fetal-maternal hemorrhage or from transfusion of platelet or granulocyte concentrate containing Rh positive red cells.
Another system of blood typing is sometimes considered prior to transfusion of granulocytes or for long-term platelet administration. The typing identifies the hla antigens that occur on leukocytes and platelets. (See also tissue typing.)
Crossmatching is another way in which blood is tested for compatibility prior to transfusion. It involves placing the cells of the donor in a sample of the recipient's serum, and cells of the recipient in a sample of the donor's serum. Absence of agglutination, hemolysis, cytotoxicity indicates that the blood specimens are compatible.
Adverse Reactions. Among the most common transfusion reactions are reactions" >antigen-antibody reactions resulting from blood type incompatibility. When blood groups are incompatible there is agglutination (clumping) of cells, hemolysis, and release of cellular elements into the serum. Signs and symptoms indicating such a reaction include burning sensation along the vein where the transfusion is given, facial flushing, chills and fever, headache, low back pain, rash, red urine, and shock. Other reactions include febrile reaction, allergic reaction with hives, wheezing, and anaphylaxis, and response to bacterial contamination. See accompanying table.

Every health care agency in which transfusions are administered should have a written policy regarding the correct steps to take in the event a patient begins to show signs of a reaction. In general, should such signs occur, the transfusion is stopped immediately, the venous line is kept open with normal saline, and emergency care is initiated.
Especially dangerous to patients with either cardiac or renal disease is hyperkalemia, an excess of potassium in the blood. If the condition is not corrected, a flaccid paralysis develops, affecting the muscles of respiration and eventually the heart muscle, which can lead to cardiac arrest. High levels of potassium in donor blood are likely to occur when the bank blood is several days old. It is estimated that the breakdown of red cells in the stored blood increases the level of potassium at the rate of one milliequivalent per liter per day.
Another possible complication is hypocalcemia, which can occur when large amounts of blood containing the additive acid citrate dextrose are given rapidly, as to a bleeding patient. Acid citrate dextrose is an anticoagulant that binds with calcium ions in the recipient's blood, removing them from circulation and thereby reducing the calcium level below that essential for normal coagulation.
Circulatory overload is a possibility any time blood is administered rapidly in large amounts. Patients who are particularly susceptible to this eventuality are the very young, the very old, and those suffering from a pre-existing cardiopulmonary or renal problem. Another difficulty that may be encountered when blood is administered rapidly under pressure is that of air embolism.
autologous transfusion reinfusion of a patient's own blood, done by either of two methods: (1) patients having a planned surgical procedure may donate their own blood within six weeks before surgery; the donated blood is processed, frozen, stored, and then thawed for use at the time of surgical need; or (2) blood lost during the operative procedure may be salvaged; this is also called autotransfusion. In the second method, blood and debris from the surgical field are aspirated into a collection chamber containing a dilute solution of heparin or citrated dextrose. The aspirate is filtered and pumped into a centrifuge chamber and the red cells are then washed with a normal saline solution. Centrifugal force separates the red cells from waste products such as debris, plasma, hemolyzed red cells, platelets, most white cells, and solution such as anticoagulant or antibiotic irrigation solution. The washed packed red blood cells are then pumped into a blood infusion bag and reinfused into the patient in the usual manner.exchange transfusion transfusion in a newborn infant of packed cells or fresh whole blood that is type O, Rh-negative, and previously cross-matched with the mother's serum, or Rh negative blood of the same type as the newborn's. Rh negative blood is used because, even though the newborn may have Rh positive blood, maternal antibodies that entered the fetal bloodstream in utero are still present in the newborn and would destroy the transfused blood cells. The blood is transfused via the umbilical vein. Exchange transfusion is used to treat either moderate to severe hemolytic disease of the newborn or hyperbilirubinemia not controlled by phototherapy. Complications may include heart failure due to either hypervolemia or hypovolemia, bradycardia or cardiac arrest from acidosis or hyperkalemia, hypocalcemia, hypothermia, air emboli, thrombolytic emboli, sepsis, intensification of hypoglycemia, and thrombocytopenia if there are repeated exchange transfusions.fetomaternal transfusion transplacental passage of fetal blood into the circulation of the mother; in small amounts it may go unnoticed, but in larger amounts it can cause anemia or edema in the fetus.intrauterine transfusion direct transfer of Rh negative blood cells into a fetus in utero in cases of isoimmunization" >isoimmunization; see transfusion" >transfusion.placental transfusion the transfer of blood from placenta to newborn at the time of birth. Blood flow through the umbilical arteries stops about 45 seconds after birth, but the umbilical vein remains patent longer. Uterine contractions enhance the transfer of blood, the volume of which has significant physiological benefits to the neonate. Since gravity influences this transfer, raising the newborn above the level of the placenta prevents a normally occurring placental transfusion. Conversely, lowering the newborn below the placental level accelerates the process.transfusion reaction any symptoms due to agglutination or hemolysis of the recipient's blood cells when blood for transfusion is incorrectly matched. See discussion under transfusion.

transfusion reaction

Blood transfusion reaction, incompatibility reaction Transfusion medicine Any untoward response to the transfusion of non-self blood products, in particular RBCs, which evokes febrile reactions that are either minor–occurring in 1:40 transfusions and attributed to nonspecific leukocyte-derived pyrogens, or major–occurring in 1:3000 transfusions and caused by a true immune reaction, which is graded according to the presence of urticaria, itching, chills, fever and, if the reaction is intense, collapse, cyanosis, chest and/or back pain and diffuse hemorrhage Note: If any of above signs appear in a transfusion reaction, or if the temperature rises 1ºC, the transfusion must be stopped; most Pts survive if < 200 ml has been transfused in cases of red cell incompatibility-induced transfusion reaction; over 50% die when 500 ml or more has been transfused; TF mortality is ± 1.13/105 transfusions Clinical Flank pain, fever, chills, bloody urine, rash, hypotension, vertigo, fainting Transfusion reactions Immune, non-infectious transfusion reactions
• Allergic Urticaria with immediate hypersensitivity • Anaphylaxis Spontaneous anti-IgA antibody formation, occurs in ± 1:30 of Pts with immunoglobulin A deficiency, which affects 1:600 of the general population–total frequency: 1/30 X 1/600 = 1/18,000 • Antibodies to red cell antigens, eg antibodies to ABH, Ii, MNSs, P1, HLA • Serum sickness Antibodies to donor's immunoglobulins and proteins Non-immune, non-infectious transfusion reactions
• Air embolism A problem of historic interest that occurred when air vents were included in transfusion sets • Anticoagulant Citrate anticoagulant may cause tremors and EKG changes • Coagulation defects Depletion of factors VIII and V; this 'dilutional' effect requires massive transfusion of 10 + units before becoming significant • Cold blood In ultra-emergent situations, blood stored at 4º C may be tranfused prior to reaching body temperature at 37º C; warming a unit of blood from 4 to 37º C requires 30 kcal/L of energy, consumed as glucose; cold blood slows metabolism, exacerbates lactic acidosis, ↓ available calcium, ↑ hemoglobin's affinity for O2 and causes K+ leakage, a major concern in cold hemoglobinuria • Hemolysis A phenomenon due to blood collection trauma, a clinically insignificant problem • Hyperammonemia and lactic acid Both molecules accumulate during packed red cell storage and when transfused, require hepatorenal clearance, of concern in Pts with hepatic or renal dysfunction, who should receive the freshest units possible • Hyperkalemia Hemolysis causes an ↑ of 1 mmol/L/day of potassium in a unit of stored blood, of concern in Pts with poor renal function, potentially causing arrhythmia • Iron overload Each unit of packed RBCs has 250 mg iron, potentially causing hemosiderosis in multi-transfused Pts Microaggregates Sludged debris in the pulmonary vasculature causing ARDS may be removed with micropore filters Pseudoreaction Transfusion reaction mimics, eg anxiety, anaphylaxis related to a drug being administered at the same time as the transfusion Infections transmitted by blood transfusion • Viruses B19, CMV, EBV, HAV, HBV, HCV, HDV, HEV, Creutzfeldt-Jakob disease, Colorado tick fever, tropical viruses–eg Rift Valley fever, Ebola, Lassa, dengue, HHV 6, HIV-1, HIV-2, HTLV-I, HTLV-II • Bacteria Transmission of bacterial infections from an infected donor is uncommon and includes brucellosis and syphilis in older reports; more recent reports include Lyme disease and Yersinia enterocolitica Note: Although virtually any bacteria could in theory be transmitted in blood, the usual cause is contamination during processing rather than transmission from an infected donor • Parasites Babesiosis, Leishmania donovani, L tropica, malaria, microfilariasis–Brugia malayi, Loa loa, Mansonella perstans, Mansonella ozzardi, Toxoplasma gondii, Trypanosoma cruzi
AcronymsSeeTxRx

transfusion reaction


Related to transfusion reaction: hemolytic transfusion reaction
  • noun

Words related to transfusion reaction

noun reaction of the body to a transfusion of blood that is not compatible with its own blood

Related Words

  • response
  • reaction
随便看

 

英语词典包含2567994条英英释义在线翻译词条,基本涵盖了全部常用单词的英英翻译及用法,是英语学习的有利工具。

 

Copyright © 2004-2022 Newdu.com All Rights Reserved
更新时间:2025/2/28 14:26:15