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TitleMedical Laboratory Technician
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Page 1

DOCUMENT RESUME*

a
ED 224 893 CE 034 548

TITLE Medical Laboratory Technician--Hematology, Serology,
. Blood Banking & Immunohematology, 10-4. Military

Curriculum Materials for Vocational'and Technical
Education:

INSTITUTION Air Force Training Command, Sheppard AFB, Tex'.; Ohio
State Univ.', Columbus. National Center.for Research
in Vocational,Education.

.

" SPONS AGENCY Office of Education (DHEW), Washington; D.C.
PUB DATE 78
NOTE 286p.; For related documents see CE '034 546-547.
PUB TYPE Guides Classrobm Use Materials (For Learner)

(051)

EDRS PRICE MF01/PC12 Plus Postage.
DESCRIPTORS Allied Health Occupations Education; Behavioral

Objectives; *Chemical Analysis; Chemistry;
Correspondence Study; Course, Content;Andependent
Study; *Job Skills; *Laboratory Procedures;
Laboratory Technology; Learning Modules; Medical
Education; *Medical Laboratory Assistants.;
Microbiolog; Postsecondary/Education; Secondary
Education; Techhical Education; Tissue Donors; *Units
of Study; Vocational Education

'IDENTIFIERS *Blood; Military Curriculum Project

ABSTRACT
This course, the thit2d of.three courses in the"

,

medical 'laboratory technician field adapted from military curriculum
rri'ateria1s for use in vocational and technicalneducation, was,designed
as a refresher Course for student self-study and evaluation. It is
sditable for use by advanced students or beginning students '-
participating in a supervised laboratory or on-the-jobjearning
situation. The course is divided inVp three volumes containing
student workbooks, readings, and tests. Volume 1 covers blood
composition and functions, blood counts, ertrocytes, leukocytes, and
,coagulation. Volume 2 presents information concernimg blood banking;
this information includes immunohematology, blood group systems,
transfusion of blood, and the opeation of a blood center. The final
volume discusses the.principles orserology, the agglutination test,
the fixation and precipition test, and the serological test for.
syphilis. A glossarY of technical terms used in the three volume's' ie
printed at the back of volume,3. Each of the vblumes contains
chapters with objectives, text,,review exercises, and answers to the
exercises. A volume review exercise (without answers) is provided.
(K)

Reproductions supplied by EDRS are the best that can be made
from the original document.

Page 2

DOCUMENT RESUMEt

ED 224 893

TITLE Medical Laboratory TechnicianHematology, Serology,
Blood Banking & Immunohematology, 10-4. Military
Curriculum Materials for Vocational'and Technical
Education:

INSTITUTION Air Force Training Command, Sheppard AFB, Te5e.; Ohio
State Univ.', Columbus. National Center-for Research
in Vocational,Education. .

k SPONS AGENCY Office of Education (DHEW), Washington; D.C.
PUB DATE 78
NOTE 286p.; For related documents see CE '034 546-547.
PUB TYPE Guides Classroom Use Materials (For Learner)

(051)- 46-

CE 034 548

EDRS PRICE MF01/PC12 Plus Postage.
DESCRIPTORS Allied Health Occupations Education; Behavioral

Objectives; *Chemical Analysis; Chemistry;
Correspondence Study; Course, Content;,Independent
Study; *Job Skills; tLaboratory Procedures;
Laboratory Technology; Learning Modules; Medical
Education; *Medical Laboratory Assistants,;
MicrobiologY; Postsecondary/Education; Secondary
Education; Technical Education; Tissue Donors; *Units
of Study; Vocational Education

'IDENTIFIERS *Blood; Military Curriculum Project

ABSTRACT
This course, the third of three courses in the'

me4ical laboratory technician field adapted from military curriculum
Materials for use in vocational and technical6education, was,designed
as a refresher Course for student self-study and evaluation. It is
sditable for use by advanced students or beginning students
participating in a supervised laboratory or on-the-jobjearning
situation. The course is divided inVo three volumes containing
student workbooks, readings, and tests. Volume 1 covers blood
composition and functions, blood counts, ertrocytes, leukocytes, and
coagulation. Volume 2 presents information concernimg blood banking;
this information includes immunohematology, blood group systems,
transfusion of blood, and the opeication of a blood center. The final
volume discusses the principles of4serology, the agglutination test,
the fixation and precipition test, and the serological test for,
syphilis. A glossarY of technical terms used in the three volumes'is'
printed at the back of volume,3. Each of the vblumes contains
chapters with objectives, text,.review exercises, and answers to the
exercises. A volume review exercise (without answers) is provided.
(cc)

Reproductions supplied by EDRS are the best that can be made
from the original document.

************************k**********************************************

Page 142

TABLE 8
EMERGENCY CROSSMATCH GUIDE

60 minutes

30 minutes

15 minutes

5 minutes or less

Full crossmatch-saline
albumin, Coombs

Release blood after al-
bumin phase. Continue
to complete crossmatch.

Release blood after
saline and albumin
phase. Continue -to com-
pletion.

Give ABO group and Rh
type-specific blood un-
crossmatched. Begin
complete crossmatch. If
necessary, give low-titer
0 negative blood.

final typing and crossmatching be accomplished
prior to all transfusions. The typing and
crossmatching should be doublechecked and
countersigned by a person familiar and current with
the detailed techniques and procedures being
uti I ized."

6-20. When time does nica allow crossmatching,
ask the physician to sign a release form
acknowledging his responsibility and accepting the
risks in giving uncrossmatched blood. 'This action
helps protect you legally from personal liability in
this situation. Obtain a sample of blood from the
patient and from the pilot tube before the unit leaves
the bank and begin a routine crossrnatch. At the first
sign of incompatibility, notify the physician. Do this
through the officer in charge of the blood transfusion
service. If the samples are compatible, complete the
necessary SF 518. Emergency crossmatching
techniques can be used to prepare blood zAen time
is short. Table 8 is a theoretical, descriptive guide
for handling emergency situations; but if local
policies direct otherwise, they should be followed.

6-21. If blood is released without the complete
crossmatch, appropriate records must reflect this
action. Whenever a patient is transfused, there is
some risk, either immediately as a . transfusion
reaction or as subsequent sensitization. The omission
of crossmatch safeguards increases that risk.
Deciding when to transfuse blood is entirely the
responsibility of the physician, and the blood banker

26

is thereby obligated to make the blood available.
You must enter the information in blood bank
records and immediately notify the chief of the blood
transfusion service whenever you relese blood
without a complete crossmatch.

6-22. Miscellaneous Problems. In addition to the
points previously covered, there is a variety of
related problems. We will mention some of the most
common difficulties encountered in a blood
transfusion service.

6-23. Additives. Nothing should be added to a
unit of blood in the blood bank by blood bank
personnel. If a biological (e.g., Witebsky group-
specific substance) is desired by the physician, and
he wishes .to add this or other substanfts (e.g.,
insulin) to the blood, the addition can be made by the
medical staff attending the palient.

6-24. Use of the universal donor. The use of 0
negative as universal donor blood is not as desirable
as using the patient's own blood type. If you do
crossmatch 0 negative blood with an A or B patient,
would you expect compatibility on the minor side?

6-25. Incompatible crossmatch. Some of the
causes of an incompatible crossmatch and suggested
followup action are given in table 9. From a
practical standpoint, it is often simpler to select a
new unit of blood for crossmatch than to undertake
detailed studies; but be sure you have not made a
common error like mistyping.

6-26. Multiple transfusions. If a patient receives

1 ''\

Page 143

TABLE 9
CROSSMATCH INCOMPATIBILITY PROBLEMS

Observ'ed 44Compatihility Some Possible Causes
t

Action Required

I. Saline or serum room
temperature

41) ABO error

(2) Cold agglutinin

.

(3) Irregular antibody

(1) Front type and Back type donor and
recipient

(2) Allow recipient blood to clot in
refrigerator (b) Agglutination dissi-
pates at 3037 degrees C.

(3) identify antibodies with reagent cells
(s.g."Panocell")

II. Saline, serum or high
protein at room tempera-
ture.

(1) Irregular antibody

(.7.1 Autoagglutinin

(3) Rouleaux

(1) Same as I (3)

(2) Auto-adsorption; see I (2),

(3) Add sallne

III. AHG qr Enzyme

.....
,

(1) Irregular antibody

(2) Autoagglutinin

(3) Positive direct Coombs

(1) Same as I (3)

(2) Auto-adsorption; see I (2)

(3) Check direct Coombs on donor or recipient
as indicated '

IV. Any phase Technical errors Investigate following:
Dirty glassware; bacterial contamination;
chemical contamination; fibrin clots;
over-cinfilfugation or centrifuge vibra-
tion.

several units of blood, a new sample must be
obtained from the patient each day for crossmatch.
Interdonor crossmatches are not necessary.

6-27. Antibody identification: If a patient
possesses an antibody that consistently results in
incompatibility, this antibody must be identified.
Panels of cells containing known antigens are
available for this purpose. When you have identified
the antibody, you must use specific antisera to select
donor blood that does not contain the corresponding
antigen.

6-28. Use of fresh blood. It is estimated that the
post-transfusion survival of red blood cells decreases
by less than 1 percent for each day of pretransfusion
storage. Platelets are far more vulnerable to storage,
dnd it is therefore desirable that platelet
concentrates be no more than 6 hours old.
Leukocytes have a relatively short lifespan in stored
blood, and the number of leukocytes contributed by a
unit of blood is relatively small. For this reason,
correction of leukopenia by the use of whole blood is
virtually impossible. Relatively few cases require the
use of freshly drawn blood. One such instance is, as
suggested, the need for platelets.

6-29. TransfusiOn complications. Patients who
receive blood may suffer a number of possible
reactions. These include pyrogenic reactions,
allergic reactions, embolism, and hemolytic*
reactions. It is also possible for a recipient to be
infected with bacteria or viruses. Though none of
these conditions is necessarily probable, their
possibility requires a certain amount of knowledge
on your part. Let us briefly consider each reaction.

6-30. There is very little you can do to prevent or
follow up a pyrogenic reaction. If the patient
develops a fever from chemical substances in the

27

blood-anticoagulaht mixture without associated
complications, this is termed "a pyrogenic reaction."
Pyrogens occur in the anticoagulant diluent as
products of bacterial contamination. In most
instances, the problem is to distinguish a pyrogenic
reaction from a more severe transfusion reaction. As
a rule, pyrogenic eactions are not fatal. An allergic
reaction is a response to practically any substance in
the blood to which the recipient is sensitive. Its
severity varies from itching and hives to respiratory
collapse. Again, this is a systemic response over
which the blood bank has very little control,
provided the response is not caused by contaminated
'blood. An allergic respdhse is usually considered
separate from incompatibility reactions in which
hemolysis or agglutination of the erythrocytes is
involved.

6-31. An embolism is the obstruction of a blood
vessel by a clot, foreign particles, or an air bubble.
Proper mixing of the blood with anticc;agulant
during collection prevents clots from forming in the
blood bag. Ordinarily, any clots present are removed
by the filter in the blood administration set. When
you collect blood, iceep air from entering the bag by
keeriing the metal ball valve in place until the needle
is in the vein. When blood is transfused under
positive pressure, air in the bag may be forced into
the recipient.

6-32. Another situation that can be critical is a
hemolytic transfusion reaction. Hemolytic reactions
are caused by intravascular hemolysis of either the
recipient's or the donor's erythrocytes, usually the
latter. The severity of a hemolytic reactiohdepends
Upon the degree of incompatibility, the amount of
blood administered, the rate of administration, and
the physical condition of the patient. Clinical

11

11/0

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Page 283

62. (035) The first sign of a syphilis infection is -called the

a. primary lesion.
b. initial lesion.0

c. primary eruption.
d. initial sore.

63. (035) Venereal syphilis differs from wlemic syphilis in geograpld-dal occurrence and

a. organs infected. .c. antibody response.
4b. causative agent. d. mode of transmission.

64. (036) The antigens used to detect reagin are

a. lipid complexes. c. Nichols antigens.
b. treponemal antigens. d. Reiter antigens.

65. (036) After the appearance of a chancre in primary syphilis, antibody response4s usatly detectable

a. immediately. c. not later than 2 weeks.
b. within 1 'week. d. within 1 to 3 weeks.

66. (036-037) A single high titer on a patient suspected ot 'having syphilis suggests that the patient

a. may or may not have the disease. c. has chancres.
b. has inactive syphilis. d: has active syphilis.

r. (037) Control specimens are used in standard syphilis tests to reproduce an established
a. limit of reactivity.
b. reactivity pattern.

c. neetive reaction.
d. antibody dilution.

68. (038) Water gihs used in standard 'test for syphilis should be checked

a. once a day. c. weekly.
b. each time used. d. twice weekly.

69. . (059) Syphilitic serums are heated at 56° C. for 30 minutes to

a. increase reactivity. c. inactivate nonspe Tic antigens.
b. inactivate the complement. d. activate reagin.

70.- (039-040) Reagin appears in the blood of a syphilitic p4tient about how man eeks after infection?

a. 1 *eek.
b. 2 weeks.

c. 5 weeks.
d. 6 weeks.

71. (040) Which of the following sources of eiror may be eliminated by performing titers on all positive
screening tests? 09
a. Mixing half quantities. c. Prozone reactions.
b. Chemically inpure *agents. d. Faulty inactivation.

35

..AKP

f

Page 284

MODIFICATIONS
fr

of this publication has (have) been deleted in

adapting this material for inclusion in the "Trial ImPlementation of a

Model System to Provide Military Curricule Materials for Use in Vocational-

and Technical Ed/ ucation." Deleted material iarvolves extensive use of

military forms, procedures, tystems, etC. and was not considered appropriate

for use in voc tional and technical education.

Me

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