Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

BLOOD BANK > 3-ABO BLOOD GROUPING - LABORATORY POLICY AND PROCEDURE > Flashcards

3-ABO BLOOD GROUPING - LABORATORY POLICY AND PROCEDURE Flashcards

(112 cards)

Start Studying
1
Q

What is the purpose of ABO blood grouping

A

Determine correct ABO group and ensure reliability of results

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What components are performed to ensure reliable ABO grouping

A

Forward typing + Reverse typing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

When is reverse typing not performed

A

Neonates or babies less than 3 months of age

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What principle describes the reciprocal relationship between red cell antigens and serum antibodies

A

Landsteiner’s Law

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What does Landsteiner’s Law state about antigens and corresponding antibodies

A

If antigen present on red cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What blood group has both A and B antigens and no corresponding antibodies

A

Blood group AB

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What does transfusion of ABO incompatible blood cause

A

Intravascular hemolysis + Hemolytic transfusion reaction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the risk of transfusing less than 50 ml of ABO incompatible packed RBC

A

May not cause death but has long-term effects

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What blood group is the universal plasma donor

A

Blood group AB

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What blood group is the universal packed red cell donor

A

Blood group O

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the clinical significance of ABO grouping

A

Ensures compatibility in transfusions + Prevents hemolytic reactions + Maternal-fetal compatibility + Medicolegal investigations + Basis for Rh typing and crossmatching

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What equipment is used in ABO blood grouping

A

Centrifuge + Micropipette + Microscope + Test tube rack

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What reagents are used in ABO blood grouping

A

Known red cell reagents + Anti-sera + 0.9% saline

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What samples are used in ABO blood grouping

A

Clotted or EDTA blood samples

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Why is normal saline used for red cell suspension

A

Isotonic prevents hemolysis + Preserves red cell structure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Why are color-coded antisera important

A

Enhance contrast + Prevent reagent mix-ups

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the principle of ABO grouping

A

Agglutination of red blood cells with specific antibodies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the difference between forward and reverse typing

A

Forward detects antigens on red cells + Reverse detects antibodies in serum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the reason for performing both forward and reverse typing

A

Check and balance to confirm ABO group

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the grading scale used in ABO typing

A

0 (negative) to 4+ (strong agglutination)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What indicates a positive agglutination reaction

A

Clumping of red blood cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What should be done if forward and reverse typing results do not match

A

Further investigation to resolve ABO discrepancy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the significance of ABO typing in transfusion safety

A

Prevents life-threatening hemolytic transfusion reactions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What law states the antigen on RBCs determines the reciprocal antibody in serum

A

Landsteiner’s Law

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What blood group has B antigens on RBCs and anti-A antibodies in serum
Blood group B
26
What two components must always be performed in ABO grouping
Forward typing + Reverse typing
27
What method is mainly used to validate ABO grouping results
Slide method
28
Who typically validates ABO grouping results
Senior medical technologist
29
What reaction causes visible clumping in forward typing
Agglutination of antigen with matching antibody
30
Why is reverse typing not performed in neonates under 3 months
Antibodies not yet developed + Maternal antibodies may interfere
31
What equipment is essential for ABO grouping test tube setup
Test tubes + Racks + Pipettes + Reagents + Centrifuge + Incubator
32
What is the recommended red cell suspension concentration for ABO grouping
3 to 5 percent
33
Why are two drops of antisera and one drop of red cell suspension used
To ensure optimal antigen-antibody ratio
34
What is the effect of excess antibodies in ABO testing
Weaker reaction + False negative agglutination
35
What is the effect of overcrowded antigens in ABO testing
False negative result due to insufficient antibodies
36
What is the centrifugation speed for ABO test tube method
1000 rpm
37
What is the centrifugation time for ABO test tube method
15 to 30 seconds
38
What should be avoided during resuspension of red cell button
Vigorous shaking that destroys agglutination
39
What indicates a positive reaction in ABO forward typing
Agglutination or hemolysis
40
What is the purpose of reverse typing in ABO grouping
Confirm forward typing results by detecting antibodies in serum
41
What color-coded antisera are used in forward typing
Anti-A (blue) + Anti-B (yellow)
42
What is the principle behind ABO grouping
Agglutination of RBCs by specific antibodies
43
What is the significance of ABO grouping in transfusion
Prevents hemolytic transfusion reactions + Ensures compatibility
44
What is the exception to performing reverse typing
Neonates under 3 months of age
45
What is the importance of labeling test tubes in ABO grouping
Prevent sample mix-up + Ensure accurate results
46
Why is normal saline used in red cell suspension
Isotonic solution prevents hemolysis
47
What is the role of the slide method in ABO grouping
Validation of results before release
48
What is the reason for performing both forward and reverse typing
Check and balance for accuracy
49
What is the purpose of preparing a 2-5% red cell suspension
Ensure optimal antigen-antibody ratio for blood typing
50
What concentration of red cell suspension is commonly used at the heart center
0.05
51
What can incorrectly prepared red cell suspensions cause
False negative test results
52
What causes false negative results when red cell suspension is too concentrated
Overcrowding of antigen + Insufficient antibody to react
53
What causes false negative results when red cell suspension is too light
Excess antibodies + Too few antigens to agglutinate
54
What type of solution can damage red blood cells causing false negatives
Hypertonic or hypotonic solutions
55
What is the principle behind red cell suspension preparation
Consistent 5% suspension critical for agglutination test sensitivity
56
What volume of anticoagulated blood is transferred to prepare red cell suspension
2-3 drops (0.2-0.5 mL)
57
What saline concentration is used to resuspend red cells
0.9% saline
58
What is the centrifugation time and speed for washing red cells
20-30 seconds at high speed (usually 1000 rpm)
59
How many times should red cells be washed
3 to 4 times
60
How is the desired red cell suspension percentage prepared after washing
Add 1 drop red cells to 19 drops saline for 5% suspension
61
What is the visual standard color for red cell suspension
Cherry red
62
What should be done if red cell suspension color is too dark
Add isotonic saline to dilute
63
What should be done if red cell suspension color is too light
Centrifuge and adjust saline volume
64
What is decantation in red cell suspension preparation
Gently pouring off supernatant without disturbing red cell pellet
65
What angle should the test tube be held during decantation
45 degrees with open end downward
66
Why is decantation preferred over aspiration
Prevents damage to fragile red blood cells
67
What is the risk of aspirating red cell suspension improperly
Suction force can destroy red blood cells
68
What materials are required for red cell suspension preparation
Anticoagulated blood + 0.9% saline + Test tubes + Centrifuge + Pipettes
69
What is the formula to calculate percent red cell suspension
%RCS = (Volume RBC / Total volume) x 100
70
What is the typical volume of saline added to achieve 5% red cell suspension in 5 mL total volume
4.75 mL saline + 0.25 mL packed RBC
71
What is the importance of washing red cells before suspension
Remove plasma proteins and debris that interfere with agglutination
72
What is the effect of using hypertonic or hypotonic saline in red cell suspension
Causes hemolysis and false negative results
73
What is the recommended centrifuge speed and time for red cell washing
1000 rpm for 15-30 seconds
74
What is the significance of proper red cell suspension in immunohematology testing
Ensures accurate blood typing and crossmatching results
75
What is the first step in reverse typing
Label tubes with patient name or ID and red cell group to be tested
76
What volume of patient serum is added to each tube in reverse typing
Two drops
77
What is the concentration of pooled red cells used in reverse typing
3 to 5 percent
78
What volume of pooled red cells is added to each tube in reverse typing
One drop
79
What is the purpose of mixing patient serum with known red cell reagents in reverse typing
To observe agglutination and avoid false negatives
80
How many test tubes are needed for ABO grouping
Five tubes (1 red cell prep + 2 forward typing + 2 reverse typing)
81
What is the agglutination pattern in forward typing for blood group A
Agglutination with anti-A serum only
82
What is the agglutination pattern in forward typing for blood group B
Agglutination with anti-B serum only
83
What is the agglutination pattern in forward typing for blood group AB
Agglutination with both anti-A and anti-B sera
84
What is the agglutination pattern in forward typing for blood group O
No agglutination with anti-A or anti-B sera
85
What is the agglutination pattern in serum grouping for blood group A
Agglutination with B cells only
86
What is the agglutination pattern in serum grouping for blood group B
Agglutination with A cells only
87
What is the agglutination pattern in serum grouping for blood group AB
Agglutination with both A and B cells
88
What is the agglutination pattern in serum grouping for blood group O
No agglutination with A or B cells
89
What law explains the reciprocal relationship between RBC antigens and serum antibodies
Landsteiner’s Law
90
What is the grading for one solid agglutinate with clear background
4+
91
What is the grading for several large agglutinates with clear background
3+
92
What is the grading for medium-sized agglutinates with clear background
2+
93
What is the grading for small agglutinates with turbid background
1+
94
What is the grading for very small agglutinates with turbid background
+/-
95
What is the grading for mixture of agglutinated and unagglutinated cells with turbid background
mf*
96
What is the grading for no agglutination with turbid background
0
97
What causes small red cell particles around a large clump in agglutination
Vigorous dislodging during resuspension
98
Why is documentation of agglutination grading important
Prevent clerical errors and provide evidence for future investigations
99
How long are blood typing worksheets typically kept
15 years
100
When should agglutination grading be recorded
Immediately during interpretation
101
What is a cause of false positive results due to remnants in glassware
dirty glassware
102
What can improper ratio of cells to serum cause in ABO testing
false negatives
103
What is the effect of overcentrifugation in ABO typing
false positive due to hard-to-dislodge pellets
104
What is the effect of undercentrifugation in ABO typing
false negative due to easily dislodged pellets
105
What can contaminated antisera cause in ABO testing
discrepant results between forward and reverse typing
106
What is the first step to check when resolving ABO discrepancies
clerical and technical errors
107
What is the effect of failure to identify hemolysis in ABO typing
false negative result
108
What should be done if unsure about hemolysis
check under the microscope
109
What is the effect of failing to add serum in serum grouping
missed reaction + possible false negative
110
Why is serum added first in serum grouping
to avoid forgetting its addition
111
What is a reason for mismatched forward and reverse typing due to technical error
contaminated reagents
112
What is the consequence of using clear serum and supernatant without proper checking
missed addition of serum

BLOOD BANK (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions