TRANS 208 Test 1 | Q & A (Complete Solutions) Explain how solid phase red cell adherence works if you are trying to detect an antibody - explain antibody testing You have a solid phase well bound with either antigen o
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TRANS 208 Test 1 | Q & A (Complete Solutions) Explain how solid phase red cell adherence works if you are trying to detect an antibody - explain antibody testing You have a solid phase well bound with either antigen or antibody that is going to detect your target of interest. For antibody testing, patient plasma and LISS is added to the wells (to enhance sensitization). They are then incubated, and then washed to remove excess antibodies that did not bind. After washing you add check cells (that are anti-IgG coated), which will bind to any antibody left in the well (bound to the wells). You then interpret the results by observing the binding patterns in the wells What is the number 1 cause of transfusion associated death? a) Misidentifying the patient when blood is being drawn b) Recording an incorrect ABO grouping for a patient c) Mix up of samples during laboratory testing d) Misidentifying the patient at the point of transfusion The patient information on a requisition is completed by a) The MLT b) The pharmacist c) The ordering physician d) The nurse e) Two of the above (c and d) Which of the below is NOT completed by the phlebotomist at the time of collection? a) Armband stickers b) Collection time and date c) Initials of the phlebotomists d) All of the above are completed by the phlebotomist Who provides the accession number for the sample? a) Phlebotomist b) Nurse c) Ordering physician d) MLT who received the samples What information must be recorded by the MLT upon receipt of a sample to the lab for transfusion testing? Accession Received by and time Previous history for patient What is the expiry date for a sample in transfusion? How long is the sample held for? Expires in 96 hours (4 days), however is held for another 3 days in case any corroboratory testing needs to be performed. Why is it important to grade reverse grouping reactions? Helps us track antibody titres over time for the patient If a sample was collected on January 16th at 8:40am, when does the sample expire? a) January 19th, 11:59pm b) January 19th, 8:40am c) January 20th, 8:40am d) January 20th, 11:59pm e) January 22nd, 12:00am What 4 things MUST be on the blood sample for transfusion testing? What happens if something is wrong or missing? Full name/alias Date of collection and time Phlebotomists initials Hospital ID if something is missing or wrong it MUST be rejected What is the correct choice for what you would do if you received a sample where the initials of the phlebotomist were missing and the patient was a hard draw? a) Process the sample as this information is the least important b) Call to see who drew blood from this patient and get them to confirm they collected these tubes, have them come initial them, then continue processing c) Reject the sample and request a new one d) Ask the physician what the best course of action is What is the reason for only holding blood bank samples for 4 days before they expire? Within those 4 days, an individual could have produced an irregular antibody, thus the old sample would not be relevant anymore Which of the below is correct for sample collection of transfusion tubes? a) 2 pink EDTA b) 2 purple EDTA c) 1 pink EDTA d) 1 purple EDTA The BB numbers are associated with of the below? a) The sample b) The patients armband c) The patients requisition d) All of the above You have a new patient, no previous history, come into the hospital who needs a blood transfusion. Which of the below is false regarding the sample you would collect? a) Two samples at two separate locations on the body, 1 min apart b) Sample 1 is for the main pre-transfusion testing c) Sample 2 confirms all the main pre-transfusion testing d) All of the above are true 2nd sample is used to confirm the ABO and RH blood type only How is sample collection different between a patient who has a history (previous patient) and a new patient who has no history? Previous patient - 1 blood sample drawn, history confirms ABO and Rh blood group New patient 2 samples, collected at 2 diff times, at 2 diff locations - s1 is for pre-transfusion testing - s2 is to confirm ABO and Rh blood type Can you use a hemolyzed sample for transfusion testing? Why or why not? what are 2 reasons this could happen? NO, hemolysis interferes with grading reactions -patient has an immune response occurring causing hemolysis -poor phlebotomy Which test is heavily impacted if a red top tube were to be used? Why? a) IAT b) DAT c) ABO d) Auto control this test is supposed to test in VIVO sensitization of RBCs, however if compliment activates in the tube, we wouldn't know Why do we use EDTA and not Red top tubes for transfusion testing? Red top tubes allow for compliment activation to occur, which will interfere with proper DAT testing, whereas EDTA tubes chelate calcium so compliment activation CANNOT occur, allowing us to ONLY see in VIVO responses Which of the below do we have to do compatibility testing for? a) RBCs b) Platelets c) Plasma d) All of the above If your patient was not given their crossmatched blood product within the 96 hour period of receiving their sample, can the blood product still be used for that patient? NO, it must be unmatched, if necessary they would need to be retested with a new sample, then they could cross match again Samples for compatibility testing are kept for a) 7 days b) 3 days c) 5 days d) 4 days T/F The hospital number and accession number are interchangeable FALSE - the accession number is tied to the SAMPLE, while the hospital number is tied to the PATIENT A specimen for a pre-admit patient is collected ___________ prior to the procedure? a) 2 weeks b) 6 weeks c) 9 weeks d) 3 weeks T/F Pre-admit samples are STAT False What TWO assumptions are made when collecting a pre-admit sample 6 weeks prior to their surgery? 1. The patient will not receive a blood transfusion in this time frame 2. The patient will not give birth during this time frame Ensures no antibodies are formed within the time of sample collection and the surgery The expiry date for a pre-admit sample is a) 4 days after receiving b) 6 weeks after receiving c) Expires after the patients surgery d) 2 weeks after receiving How many days in advance are operating room schedules posted so that blood bank can review all pre-admit results? a) 1-2 days b) 3-4 days c) 2-3 days d) 4-5 days You have a patient who is 20 weeks pregnant and was scheduled for a surgery in 6 weeks, so you received a pre-admit sample and preformed all necessary testing. You receive a notification that your patient has experienced a fall in which they had to go to the hospital, however they were discharged with no need for intensive medical intervention and the same surgery date. Which of the below is true? a) The preadmit sample should still be valid because they did not receive a blood transfusion b) The pre-admit sample should still be valid because the patient did not give birth c) The pre-admit sample may not be valid as the could have developed antibodies against fetal antigens if they were exposed during the fall d) The pre-admit sample may not be valid as they could’ve been given medication that caused them to develop an antibody Your pre-admit patient had their surgery pushed by 24 hours past the 6 week mark, what would you do? a) Collect a new sample as it would expire before they got their surgery b) Keep the current test results as 24 hours will not affect the testing c) Ask the doctor what to do d) None of the above What is done for a type and hold specimen? ONLY pre-transfusion testing then hold, you would not perform a x match When is the phenotyping and x-matching of pre-admit samples done? a) Upon completion of pre-transfusion testing b) 2 weeks before their surgery c) the evening before their surgery d) Does not matter when Which of the below regarding pre-admit samples is true a) The specimen expiry date is 11:59pm on the day of the surgery, if it is not performed that day the specimen expires b) The specimen expiry date is changed to 96 hours starting at 12:01am on the day of the surgery c) The specimen expiry date is changed to 96 hours starting at the start time of their surgery d) The specimen expiry date is changed to 96 hours startingat 12:01am the night before their surgery If a patient has an irregular antibody, what would the MLT do in the below situation (for cross matching) - No units required - Units required - No units required (x matches regardless) - Units required (doubles the needed x matches) T/F Hospital numbers and accession numbers are interchangeable False - accession number is tied to a specific sample - hospital number is tied to a patient in a hospital Which of the below is the most critical test of pretransfusion testing? a) Rh typing b) ABO typing c) IAT d) DAT In which of the below situations would you perform weak Du testing? a) Normal pretransfusion testing when a patient shows Rh negative at immediate spin b) Blood donor getting typed for the first time and shows up as negative at immediate spin for Rh c) An Rh negative mother whose baby showed up as Rh positive at IS d) Two of the above **not C because you would only do Weak Du testing on a baby who shows up as NEGATIVE at IS If a babies test DAT shows positive, what is occurring in their body? a) They have an autoantibody to their RBC antigen causing autoimmune hemolytic anemia b) They have an autoantibody to their RBC antigen causing HDFN c) They have maternal alloantibodies attached to their RBC antigen causing HDFN d) They have maternal allo-antibodies attached to their RBC antigen causing autoimmune hemolytic anemia Which of the below is not a correct interaction for DAT? a) mothers antibody attached to babies RBC during HDFN b) Drug antibody attached to patients RBC during drug-induced hemolytic anemia c) Patient autoantibody attached to own RBC antigen during autoimmune hemolytic anemia d) Donor allo-antibody attached to patient RBC during a hemolytic transfusion reaction **Patient allo antibody attached to donor RBC Which of the below could be missed if a DAT was not performed? a) HDFN b) Autoimmune hemolytic anemia c) Drug induced hemolytic anemia d) Hemolytic transfusion reaction IAT would be negative, DAT would be positive! Which of the below commonly is missed in pre-transfusion testing due to low antibody titres? a) Kell antibodies b) Duffy antibodies c) Lewis antibodies d) Kidd antibodies What are two limitations of antibody screen tests? 1. Will not detect antibodies to low incidence antigens/ if the screen cell does not have a specific antigen then it will not detect the antibody 2. Ab screen test will not detect low concentrations of antibodies What is the protocol for how many cells should be included in an antibody panel for a new patient presenting with an irregular antibody? a) 1 panel, 10 cells b) 2 panels, 10 each panel c) 1 panel, 20 cells d) 2 panels, 5 cells each panel e) Two of the above are acceptable (b and c) *as long as 20 cells are utilized You have a returning patient where their last sample was provided 10 months ago, which of the below is the correct course of action? a) Complete a 20 cell panel b) Complete a 10 cell panel c) Complete 2, 10 cell panels d) Two of the above are acceptable ** Only good for <12 months, if the patient did not provide a sample for >12 months, must treat as a new patient You have a returning patient where their last sample was provided 13 months ago, which of the below is the correct course of action? a) Complete a 20 cell panel b) Complete a 10 cell panel c) Complete 2, 10 cell panels d) Two of the above are acceptable **>12 months, treat like new patient If you are required to give a patient least incompatible blood, what should the cross match reaction strength be compared to? a) Less than the IAT b) Less than the DAT c) Less than the auto control d) All of the above **no point in giving them blood that reacts worse than their own blood If you have a low concentration of 1 antibody, would you expect it to follow a pattern of reaction? Not necessarily, could be absent on some cells (single dose) Which of the below situations would you expect to see a pattern of reaction? a) single antibody in high titre b) Single antibody in low titre c) multiple antibodies, both high titre d) multiple antibodies, one high titre, one low titre e) Two of the above What would you expect to see in your antibody panel if your patient had 2 antibodies? (What clue) More than 2 reaction strengths The DAT is an in _______ test, while the auto control is an in __________ test vivo, vitro When would you be concerned about low antibody levels in a patient? a) If they are on drugs that stimulate antibody formation b) If they received a previous transfusion c) If they had a previous pregnancy d) If they are old or young What is something you would be concerned about when performing pre-transfusion testing on a mother who gave birth recently? RhIg could show up as positive for Anti-D Which of the below could cause the formation of an irregular antibody? a) Plasma transfusion b) RBC transfusion c) RhIG injection d) All of the above You have a recently pregnant patient who is having pre-transfusion testing done on them (they gave birth recently). They have no previous history of transfusions. Their ABO shows they are A positive, however their antibody screen shows positive in both screen cells 1 and 2. You decide to run screen cell 3 and it is negative. What is the most likely scenario? a) They have an auto-antibody and a DAT and panel should be run b) They have an allo-antibody and a panel should be run c) They were given RhIG recently which is acting as an anti-D d) The patient has an auto-anti-D which is causing the positives in SC1 and SC2, but negative in SC3 To satisfy the rule of three using a select cell panel, which of the below is what you should select? a) Cells that are double dose for one antigen, while completely lacking the antigen to the other possible antibodies b) Cells that are single dose for one antigen, while completely lacking the antigen to other possible antibodies c) Cells that are double dose for both antigens of possible antibodies d) Cells that are single dose for both antigens of possible antibodies T/F Phenotyping patient RBCs helps to eliminate possible antibodies and prove their presence as well False only used to eliminate possible antibodies T/F You should perform select cell panels prior to phenotyping patient cells True Which of the below is true regarding Ficin? a) Can be used to destroy certain antigenic determinants b) Removes negatively charged molecules such as sialic acid to allow antigens to protrude more c) Removes positively charged molecules such as sialic acid to allow antigens to protrude more d) Adds negatively charged molecules such as sialic acid to allow antigens to protrude more e) Two of the above (a and b) What is the difference between the 1 stage and 2 stage enzyme method? In the 1 stage the panel cell, patient plasma, and enzyme are mixed, incubated and read right away, while in the two stage your panel cells and enzyme are mixed, incubated, then washed, then patient plasma is added to prevent cellular debris from interfering with interpretation T/F Sets of treated cells have different cells compared to regular panel cells in the same set False - same cells, one is just treated, the other is untreated In what two scenarios can you not phenotype patient cells? Recent transfusion (within 3 months) If their DAT is positive because their RBCs may be coated with too many Antibodies to get a phenotype Which of the below would you not use an enzyme panel for? a) Kidd b) Duffy c) Rh d) Kell e) MNS If you were picking units to transfuse for an AB positive person, which would be the most appropriate unit to give them if Ab positive blood wasn't available? Explain why a) A positive b) B positive c) O positive d) A negative e) B negative A types because it is statistically higher amount in the population, AND because group A people produce LESS anti-B than a group B person produces Anti-A (RBC units have small amounts of donor plasma containing donor antibodies) Do we make more anti-A or anti-B? Anti-A!! List the 1st, 2nd, 3rd and 4th choice for transfusing an AB person 1: AB 2: A 3: B 4: O Who should you absolutely never give Rh pos blood to? (2) Rh negative women of child bearing years Rh negative individual with an Anti-D already preformed T/F Antisera that targets Kell, Kidd, and Duffy antigens are always IgG, while antisera that targets the MN antigens are always IgM False - not based on what we physiologically make in our bodies, its how cheap it is to design them - IgM is better than IgG You have identified an irregular antibody in a patient. What should you do when picking blood units? a) Phenotype the patient RBCs so you don't give them incompatible blood b) Phenotype the donor RBCs so you don't give them incompatible blood c) Phenotype the panel cells that you performed the antibody screen with to identify the antibody so you can cross match d) Check all the labels for donor units until you find one that has been phenotyped and lacks the correct antigen Is an IgM or IgG antisera more ideal? Why? IgM is more ideal because you can get results at immediate spin, whereas with IgG you have to go through the whole incubation and AHG process which takes time What are your two controls you use for phenotyping? What is their purpose? Negative = known negative to ensure reagent specificity Positive = known single dose (weak) positive to ensure reagent reactivity (sensitivity) Typically units are selected to manage inventory appropriately, which means selecting units that are closest to expiry as long as they will meet the patients needs. What is one situation in which a patient would require FRESH blood for transfusion? Heart patients (surgery) T/F You should always make sure to inspect the transfusion bag for debris or hemolysis or clots prior to performing computability testing True - no point in compatibility testing if the bag is bad Which of the below is not a selection criteria for appropriate blood RBC units? a) Surgical blood order schedule b) Expiration dates c) Presence of irregular antibodies d) Presence of a low frequency antigen e) All of the above are selection criteria What are the 7 steps to compatibility testing? 1. Accurate Pt ID 2. Proper collection 3. Review medical history 4. Accurate pre-transfusion testing & Additional testing if necessary 5. Accurate ABO & Rh determination of donor units (CBS) 6. X match 7. Transfuse and monitor patient How long does someone stay in the vicinity of the patient for after they receive a transfusion? What kinds of things are they looking for? 15 min; checking heart rate and blood pressure, temperature (increase), CBC (Hgb monitoring) How much should the Hgb levels increase in a patient after they have been transfused with blood if they were compatible? a) 12g/L b) 10g/L c) 20g/L d) 5g/L e) None of the above T/F Cross matching is an in-vivo procedure to forecast a safe and viable transfusion of blood into a recipient False - in vitro What are the two reasons we do Cross-matching? What does the procedure do to meet these goals? 1) To prevent life-threatening or uncomfy transfusion reactions: serves to double check ABO errors 2) Ensure RBC survivability in patient (in vivo): second means of antibody detection to catch any that may have been missed in the screen What is the difference between a major and minor x-match? Major: tests compatibility between donor RBCs and patient plasma and MUST be completed Minor: tests compatibility between recipient RBCs and donor plasma A minor cross match tests ___________ RBCs against ________ plasma, while a major cross match tests __________ RBCs against _________ plasma. Recipient, Donor Donor, recipient (must be done) Why don't we do Minor cross matches anymore? The donor should not have any irregular antibodies that would harm recipient RBCs as the CBS screens donors for irregular antibodies When would you perform an Immediate spin cross match? What about an Antiglobulin cross match? What do they each do? Immediate spin confirms ABO compatibility - done when the patient has no history of irregular antibody and one did not get identified in the pre-transfusion testing AHG matching is done to demonstrate IgG antibody compatibility - done when the patient has a clinically significant antibody or when they have a history of one Which of the below is false regarding types of Major X-matches? a) Immediate spin cross matching is to demonstrate ABO compatibility b) AHG cross matches are used to demonstrate IgG and IgM antibody compatibility c) Immediate spin cross matching is completed i the patient has no history of irregular antibodies AND none were identified in pre-transfusion testing d) AHG cross matching is completed if the patient has had a history of a clinically significant antibody or one was detected in pre-transfusion testing What are two indicators in that tell you that the unit you have selected is incompatible with the patients plasma? 1) Hemolysis 2) Agglutination If you must transfuse a patient with least incompatible blood, what test should you use to compare reactions strengths to assess if it is worth transfusing? a) DAT b) Autocontrol c) Antibody screen d) Antibody panel If the patients antibody screen is positive and the RBCs of all donors tested are incompatible with patient plasma, which of the below is the likely cause? a) Antibody to a low incidence antigen b) Antibody to a high incidence antigen c) Multiple antibodies present d) Two of the above e) All of the above When would you expect a patient has an antibody to a low incidence antigen (if the patients units have been crossmatched)? The patients antibody screen is negative and only one donor unit of all selected are incompatible T/F Autoantibodies typically have specificity for antigens of relatively low frequency False – high Your patient had a partial phenotype of K+ e- and it seems they have an antibody that showed up in the screen. You could not narrow down what antibody was present, so you selected the general unit of e- cells. The patients Hgb did not increase after the transfusion. Which of the below is the most likely? a) They were phenotyped wrong in the past and likely have an anti-K allo-antibody b) The donor unit was incorrectly phenotyped and they posessed the e antigen, therefore the recipient had an allo-anti-e c) The patient likely has an allo-anti-K that reacted with the donor blood who was K+ d) The patient likely has an auto-anti-K that reacted with donor blood who was K+ If a donor has drug auto-antibodies, how would this interfere with cross matching? Would you see it in an IS x-match? What about a AHG cross-match? If it wasn’t picked up in cross matching, how could you tell that this was occurring? Will cause incompatibility in every patient we try to test it for - Wouldn't catch it on immediate spin x-match (no AHG phase), but there would be no increase in hemoglobin - Would catch it in an AHG cross match What kind of antibodies would the CBS not pick up on in their pre-transfusion testing? a) Natural Autoantibody b) Drug autoantibody c) Drug allo antibody d) Natural allo antibody would make them incompatible with everyone!! You sent out what seemed like compatible blood to a patient that had no antibodies or previous history (IS-match only). The physician called and said that they want to do an investigation into a transfusion reaction as the patients hemoglobin levels did not rise after the transfusion. You went back and performed more antibody testing with high and low frequency antigens, but nothing has come up. What is the most likely explanation for this? a) You gave the patient the wrong bag of blood that was actually incompatible b) The donor had allo-antibodies to an antigen the recipient possessed c) The donor has a drug-autoantibodies coating the cells d) None of the above are suitable explanations Wouldn’t show up at the IS spin (needs an AHG incubation phase) and its nothing wrong with the patient plasma hence why you couldn't find anything Why would a drug-auto-antibody that the DONOR has cause an incompatible blood transfusion? The donor RBCs would be coated with their own antibodies, which will get eaten by the recipients phagocytes What could you do to check and see if a patient had rouleaux and not agglutination? SALINE REPLACEMENT In which of the below patients would you have to wash your RBCs very well prior to cross-matching or performing transfusion testing? a) Patient with acute leukemia b) patient with acute severe gastrointestinal infection c) Patient with multiple myeloma d) Patient with diabetes What are the 6 different ways that will cause a positive (incompatible) X-match? 1) ABO incompatible 2) Patient allo-antibody 3) Patient auto-antibody reacting with patient antigen 4) Donor auto-antibody coating RBCs 5) Abnormalities/high protein levels causing rouleaux in patient plasma 6) Contaminants in the testing environment
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