MAJOR CROSSMATCHING

Question 1

A procedure used to determine the compatibility between red cells of the donor and serum of the recipient (DROPS)

Answer 1

MAJOR CROSSMATCH

Question 2

Detects antibodies in the recipient’s serum that may damage or destroy the red donor’s red cells

Answer 2

MAJOR CROSSMATCH

Question 3

Methods in major crossmatching

Answer 3

1. IMMEDIATE SPIN PHASE
2. HIGH PROTEIN PHASE
3. ANTIGLOBULIN PHASE

Question 4

Also known as the saline or room temperature phase

Answer 4

IMMEDIATE SPIN PHASE

Question 5

Detects most ABO incompatibility and may be performed when the antibody screen is non-reactive and there is no history if unexpected antibodies

Answer 5

IMMEDIATE SPIN PHASE

Question 6

The simplest and most frequently used method to demonstrate ABO compatibility

Answer 6

IMMEDIATE SPIN PHASE

Question 7

Detect antibodies reacting at room temperature

Answer 7

IMMEDIATE SPIN PHASE

Question 8

Also known as incubation at 37C or thermophase

Answer 8

HIGH PROTEIN PHASE

Question 9

Detects high-altered IgG antibodies

Answer 9

HIGH PROTEIN PHASE

Question 10

HIGH PROTEIN PHASE enhancement medium and incubated for:

Answer 10

albumin or LISS
incubated for 15-60 mins at 37C

Question 11

IgG’s sensitize RBCs

Answer 11

HIGH PROTEIN PHASE

Question 12

Also known as the INDIRECT ANTIGLOBULIN or AHG phase

Answer 12

ANTIGLOBULIN PHASE

Question 13

The tube is washed three times with saline. After final decanting of saline, the AHG reagent is added.

Answer 13

ANTIGLOBULIN PHASE

Question 14

Detects non-agglutinating warm antibodies (igG) that are possibly not detected in the incubation phase

Answer 14

ANTIGLOBULIN PHASE

Question 15

serves as a bridge between sensitized RBCs producing agglutination

Answer 15

AHG

Question 16

ANTIBODIES DETECTED

IgM antibodies

Detects ABO incompatibility often due to incorrect typing

Answer 16

Saline phase

Question 17

ANTIBODIES DETECTED

IgG antibodies - high titered Rh antibodies

High protein, albumin enhances Rh antibodies

Answer 17

High Protein Phase

Question 18

ANTIBODIES DETECTED

IgG antibodies - most immune antibodies

Answer 18

Antiglobulin Phase

Question 19

Reagents Used

come from group O individuals who have been typed for the most common and most significant RBC antigens

Answer 19

Screen cells/ RBC reagents

Question 20

Reagents Used

Various enhancement reagents, or potentiators, may be added to the test system prior to the 37 C incubation phase to increase sensitivity. Such as:

Answer 20

LISS, 22% Albumin, and PEG

Question 21

is added to/ included in the test system as it allows for agglutination of incomplete antibodies

Answer 21

AHG reagent (monospecific or polyspecific)

Question 22

Any tube test that is negative after adding AHG reagent should be controlled by adding

Answer 22

Coombs’ control cells

Question 23

Coombs’ control cells are from

Answer 23

Group O Rh-positive RBCs that have been coated with anti-D.

Question 24

A procedure used to determine compatibility between the serum of the donor and the red cells of the recipient (PRODS)

Answer 24

MINOR CROSSMATCH

Question 25

Detects antibodies in the donor’s serum that could potentially react with the patient’s cells.

Answer 25

MINOR CROSSMATCH

Question 26

It has been completely eliminated in most blood banks because donor samples are screened beforehand for common antibodies.

Answer 26

MINOR CROSSMATCH

Question 27

IMMEDIATE-SPIN PHASE procedure:

Answer 27

7 Into an appropriately labeled stube, adds 2-3 drops of patients serum 8 Adds one drop of donor’s RBC suspension 9 Mixes and centrifuges tube for one minutes 10 Taps tubes gently and examines for hemolysis/agglutination a. Proceeds to next step if reaction is absent b. Stops and records results if reaction is present

Question 28

37C or INCUBATION PHASE procedure

Answer 28

11 Into the same tube, add 2 drops of enhancement medium 12 Gently mixes and incubates tube at 37C for 30 minutes 13 Re-centrifuges tubes 14 Taps tubes gently and examines for hemolysis/agglutination a. Proceeds to next step if reaction is absent b. Stops and records results if reaction is present 15 Washes cells thrice with saline and decands last washing thoroughly

Question 29

ANTIGLOBULIN PHASE procedure:

Answer 29

16 Add 1-2 drops of AHG reagent to the tube 17 Mixes and centrifuges for one minute 18 Taps tubes gently and examines for hemolysis/agglutination 19 Observes suspicious reactions microscopically (HPO) 20 Records results

Question 30

Grading: No agglutination or hemolysis

Answer 30

Negative

Question 31

Grading: Small agglutinates, turbid supernatant

Answer 31

1+

Question 32

Grading: Medium-sized agglutinates, clear supernatant

Answer 32

2+

Question 33

Grading: Several large agglutinates, clear supernatant

Answer 33

3+

Question 34

Grading: One solid agglutinate, clear supernatant

Answer 34

4+