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What is the blood component and blood type for when an emergency uncross matched request is ordered? And why?
Type O positive for those above childbearing years. (greater than 50 years old)
Type O negative for those of childbearing years.
Type A plasma
These are chosen because it represents the majority of the population.
What are all requirements for pre-transfusion testing?
ABO/Rh, antibody screening, crossmatching
If antibody screen is positive, identify antibody and select antigen negative units
Differentiate TACO vs TRALI transfusion reactions
TRALI: transfusion associated lung injury, edemia, damage to lung capillaries, hypotension, acute lung injury, oxygenation and ventilation, DUE TO HLA ANTIBODIES
TACO: hypertension, circulatory overload, managed by supplemental oxygen, there is too much fluid inside your blood vessels for your heart to pump effectively
what is the difference between major and minor crossmatches
Major crossmatches are routinely done before a patient is transfused (unless massive or emergency release), it tests RBC from donor, and recipient plasma to see if the donor has antigens that patient antibodies will destory, helps keep blood products given to patient safe.
Minor crossmatches: pt RBC tested against donor serum, not routinely done, this is due to other factors including dilution affect, pt serum dilutes any antibodies that donors may have.
What should happen if the DAT is positive?
IF the autocontrol is pOs?
DAT pos, do elution
AC positive, do DAT
A: first choice is A, second is O
B: first choice is B, second is O
AB: first choice is AB, second choice is A or B, and third choice is O
O: first choice is O
Describe what types Rh positive/negative get
Rh positive can get positive or negative
Rh negative can get only negative unless they are at critical inventory levels in the blood bank or they have received more than four units.
Why would a prewarming technique be performed for an antibody screen or crossmatching
Prewarming for the antibody screen or crossmatching can remove cold agglutins antibodies that are not dangerous, but need to be taken out because they make the clinically significant antibodies become undetectable.
If this procedure is done for a crossmatch, a regular immediate spin crossmatch must be performed to detect ABO incompatibility
Describe the three types of crossmatches and requirements
Immediate spin: done to detect ABO incompatibilities, done during downtime, or when there isn't 2 t.confs, the patient cannot have clinically significant antibodies
AHG crossmatch: taken through all phases because the patient has a clinically signfiicant antibody that if met with its matched antigen will result in RBC destruction
Electronic crossmatch: done by scanning barcode form donor units and computer computers compatiblity, only done when there is 2 t confs and patients does not have clinically significant antibody.
What are false positives and false negatives for the AHG crossmatch?
False positives: rouleux, passively transfused antibody, dirty glassware, over centrifugation, polyagglutination, autoantibody, contamination
False negative: failure of AHG, undercentrifugation, inadequate washing, procedural errors,
List the first, second, and third choice for each blood type if they are getting plasma
A: First choice A, second choice AB
B: first choice B, or AB
AB: first choice AB
O: first choice O, second choice A, third choice: B or AB
Name, unit number, DOB, mrn, patient and donor blood type, BB ID number, exp date, recipient location, etc.
TAGVHS is fatal and can be prevented by irradiated blood products, it attacks recipient bone marrow, liver, and skin
PTP: attacks platelets this causes severe bleeding
These are both delayed transfusion reactions
List the frequencies of ABO types and RH
O: 45
A: 40
B:11
AB: 4
RH pos: 85
RH neg: 15
Identify pre existing antibodies to red blood cells antigens (alloantibodies)
identify if the patient has been through sensitizing events like pregnancy, transplant, or transfusion
So that the blood bank can provide antigen negative donor blood to avoid reactions.
Warn of delayed hemolytic reactions, and indicates risk of severe allergic reactions so that they can be premedicated with antihistamines or steroids to help.
When donating plasma, AB is the universal donor, and O is the universal recipient
When donating RBC, O is the universal donor, AB is the universal recipient
Why does a new crossmatch sample have to be collected every 72 hours in the cases of pregnancy or transfusion?
Those events are sensitizing, and can illicit immune responses and stimulate antibody production. If samples are tested within that time frame, testing may not detect clinically significant antibodies that can result in transfusion reactions, so this rule ensures that we can select safe units for patients.
Describe the prewarming procedure
Prewarm saline, label tubes for RBC suspension and serum
Incubate these for five or ten minutes, without removing tubes use a prewarmed pippete to add serum to RBC suspension, incubate for 30 or an hour, wash cells by refilling with saline, add anti IgG, and spin and record, add check cells to negative reactions
What is an antibody screen
What does the reagent red cells have to express what kind of antigens
Testing patient serum to for detectable antibodies, going through all phases of immediate spin, incubation at thirty seven, and AHG
Purpose is to detect clinically significant antibodies that patient may have
Reagent RBC must express D, C, E, c, e, M, N, S, s, Lea, Leb, P1, K,k, Duffy a, Duffy b, Kidd a, Kidd b
What is the dosage effect and its importance for antibody identification?
The quality of antigen expression is influenced by a heterozygous or homozygous (strongest) allele
Antibodies that are weakly reactive may not be detected if they are tested with red cells expressing only a single dose of the antigen.
Why would someone need a RBC transfusion?
To replenish volume or increase oxygen carrying capacity because RBC carry oxygen.
Describe the order of investigation of a transfusion reaction and list the types of reactions a patient could have.
STOP TRANFUSION
maintain IV access and keep line open, replace tubing with new set of primed 0.9 saline, DO NOT flush existing IV, notify physician and blood bank
Assess the patient condition, and perform clerical checks (ID of patient, ID of unit, note unit condition for hemolysis or leakage), Blood bank will perform DAT, elutions, repeat of ABO/RH, urine tested, and sample sent to micro for bacterial culture, and medical staff give the patient supportive treatment
Types of reactions: allergic, febrile nonhemolytic, TRALI, TACO, delayed/acture reactions, transfusion associated graft verses host disease, Post transfusion purpura,etc
Describe the different types of "type" orders and the advantages and disadvantages of them
Type: gives us knowledge of patients ABO/RH type, but antibodies are
Type and screen: blood type is known but antibody screen is not performed
Type and crossmatch: all transfusion testing completed but units are taken out of inventory that cannot be used by other patients.
Hold: advantage that it saves time, calls for faster turnaround because we already have the tube in the blood bank and don't have to wait on a phlebotomist to draw from the patients.
What is the purpose of an autocontrol and the purpose of a DAT
Autocontrol: testing the patient against themselves (serum and their RBC), to detect autoantibodies, it can be drug included, autoimmune hemolytic Anemia, and lab errors
DAT: detect coated RBC in vivo with IgG antibodies or complement can be drug induced, false positive with Wharton jelly, jab errors, or hypergammaglobulinemia
What are the percentages of the population for people who lack Kell, Duffy a, and Kidd a
Kell: 91 percent
Duffy A: 34 percent lacks
In west African and African American populations the fy(a-b-) pehnotype is common and provides resistence to plasmodium Vivax malaria
Kidd A: 23 percent of population
Most Blacks have Kidd A