Block 8 Exam Flashcards

(329 cards)

1
Q

What type of stain should be used for a blood smear?

A

Wright-Giemsa stain or similar

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

What is the RBC portion of a CBC called?

A

Erythrogram or hemogram

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

What is the job or RBC?

A

Carry O2 to cells and carry CO2 back to lungs

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

What is the equivalent term to hematocrit (HCT)?

A

PCV (packed cell volume)

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

What does anisocytosis mean?

A

Different sized RBC

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

What does polychromasia mean?

A

Different colors of RBC (blue)

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

What must be done prior to running a CBC with EDTA?

A

Blood needs to be mixed

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

If hematocrit is 45 what would you expect the hemoglobin to be?

A

Hemoglobin is 1/3 of the hematocrit
15

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

Are HCT and PCV the same?

A

Pretty similar but measured in different ways

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

How do you manually determine packed cell volume?

A

Microhematocrit tube

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

What does lipemic (milky) plasma indicate?

A

Often after eating, increased TP

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

What does hemolyzed (red) plasma indicate?

A

Rupture of RBCs during collected or from disease

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

What does icteric (yellow) plasma indicate?

A

Increased bilirubin (common in large animal

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

Are manual counting methods of RBC accurate?

A

No

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

What are reticulocytes?

A

Immature RBCs (larger and less hemoglobin)

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

What makes up the erythrocyte indices?

A

MCV = mean corpuscular volume
MCHC = mean corpuscular hemoglobin concentration

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

What is microcytic?

A

Decreased MCV

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

What is macrocytic?

A

Increased MCV

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

What is normocytic?

A

Normal MCV

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

What is MCHC?

A

Ratio of hemoglobin to a volume of RBC

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

What is a low MCHC? What is it associated with?

A

Hypochromic
Regenerative response from iron deficiency

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

What is an increased MCHC due to?

A

Artifact

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

What is RDW

A

RBC distribution width
Numerical expression of variation in RBC size (anisocytosis)

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

What does decreased hematocrit mean?

A

Anemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What determines if anemia is regenerative or non regenerative?
Reticulocytes
26
What is the first thing to do on a blood smear?
Evaluate quality of blood smear grossly
27
Where should you go on a blood smear to evaluate the cells?
Counting area
28
What shape are camelid’s RBC?
Oval
29
What is unique about birds and reptiles RBC?
They’re nucleated
30
What is it called when RBCs are in a row?
Rouleaux formation
31
What species can a Rouleaux formation be normal in?
Cats and horses
32
What does a Rouleaux formation indicate?
Increased proteins due to inflammation
33
What are irregular clumps of RBCs due to antibody coating called?
Agglutination
34
What does agglutination often indicate?
IMHA
35
What should you do if you can’t differentiate a Rouleaux formation from agglutination?
Saline will disperse rouleaux formations but not agglutination
36
What is a variation in RBC size called?
Anisocytosis
37
What is polychromasia?
Larger, bluer cells that are immature RBCs
38
What does increase polychromasia indicate?
Regenerative response to anemia
39
What is the difference between polychromasia and reticulocytes?
Polychromasia is used when stained with Wright-Giemsa Reticulocytes is used when stained with new methylene blue
40
What are punched out or bowl cells?
Artifact
41
What is basophilic stippling?
Punctate basophilic granules that consist of ribosomes and poly ribosomes (Circular with blue dots on the inside)
42
What does basophilic strippling indicate?
Regenerative anemia in ruminants Lead toxicity in dogs
43
What do nucleated RBCs indicate with reticulocytes?
Just part of regenerative response
44
What are Howell-Jolly Bodies?
Nuclear fragment resulting in round, basophilic bodies in RBC
45
What would a Howell-Jolly body indicate?
Increased in some regenerative anemias
46
What are spherocytes?
RBCs are smaller and lack a central zone of pallor (white zone)
47
What do spherocytes indicate?
They form when antibodies bind to RBCs and part of the RBC is phagocytized in the spleen
48
What disease do spherocytes appear in?
IMHA
49
What is the term for RBCs with abnormal shapes?
Poikilocytes
50
What is the term used for RBCs that become poikilocytes through mechanical trauma?
Schistocytes
51
What is the poikilocyte with 1-2 projections on RBC surface?
Keratocytes
52
What are keratocytes from?
Physical or chemical injury Also iron deficiency anemia and liver disease
53
What is the poikilocyte that has thorny projections from it?
Acanthocytes
54
What are acanthocytes caused by?
Abnormal RBC membrane lipids Liver disease, hemangiosarcoma, DIC
55
What is the poikilocyte that have uniformly spaced projections?
Echinocyte Usually an artifact
56
What are cells with a dot in the middle of the central zone?
Leptocytes
57
What are differentials for leptocytes?
Liver disease, hypothyroidism, iron deficiency
58
What is an oxidized hemoglobin protrusion from RBC surface?
Heinz bodies
59
What induces Heinz bodies?
Oxidants, drugs, and toxins Stain better with new methylene blue
60
What are erythrocytes where hemoglobin is condensed on one side of the cell?
Eccentrocytes
61
What causes eccentrocytes?
Zinc to toxicity Red maple leaf toxicity
62
What are tear-drop shaped RBCs?
Dacryocytes
63
When are dacryocytes seen?
Sick camelids
64
What are mouth-like slits in RBCs?
Stomatocytes Artifact
65
What 3 things will be decreased in an anemia patient?
PCV (HCT) Hemoglobin (Hgb) concentration RBC count
66
What is used most commonly in veterinary medicine to measure RBC amount?
PCV (HTC) Accurate and cheap
67
What causes anemia?
RBC loss or destruction is faster than RBC production or RBC production is decreased
68
What will PCV and TP be if P is dehydrated (Increased or decreased)?
Increased
69
What is increased TP and PCV due to dehydration called?
Relative polycythemia
70
What happens to TP and PCV with over hydration?
Decreased TP and PCV
71
What is decreased TP and PCV from overhydration called?
Relative anemia
72
What are clinical signs of anemia?
Weakness, hyperpnea, pale MM +/- icterus, tachycardia or murmur, and fever
73
What can red or reddish brown urine indicate?
Anemia Hematuria: blood in urine Hemoglobinuria: Hemoglobin in urine from hemolysis
74
What does dark yellow urine indicate?
Anemia Bilirubinuria: bilirubin in urine
75
What does melena (digested food in feces) indicate?
Anemia
76
What is the regenerative response to anemia in the bone marrow?
Erythropoiesis
77
What number helps you determine if the anemia is regenerative or non-regenerative?
Reticulocytes
78
What does increased reticulocytes indicate? What do normal reticulocytes numbers indicate?
Regenerative: A bone marrow response to replace RBCs Non-regenerative
79
What are common regenerative anemia diseases?
Acute hemorrhage or hemolysis
80
What are common non-regenerative anemia diseases?
Chronic diseases: CKD or primary bone marrow disease
81
What is physiological reticulocytosis
Dogs may release reticulocytes from excited or after exercise
82
Are reticulocytes reliable in ruminants?
No, use basophilic strippling instead
83
Are reticulocytes reliable to use in horses?
No, use a serial MCV and RDW (over several days) to asses regeneration
84
How long after acute damage does a reticulocytes response occur?
3-5 days
85
What other 2 characteristics do anemic hemograms usually show?
Macrocytic and hypochromic Nonregenerative are usually normocytic and normochromic
86
What is another reason (besides regenerative anemia) that a patient would be macrocytic and hypochromic?
Iron deficiency anemia
87
What would microcytic normochromic RBCs indicate?
Portosystemic shunt
88
What would macrocytic and normochromic RBCs indicate?
Horses with regenerative anemia Cats w/ FeLV infection
89
What are the 3 classification schemes for anemia?
Reticulocytes count RBC indices Pathogenesis
90
What is hemolysis?
RBC destruction
91
What is the term for decreased platelets?
Thrombocytopenia
92
Is iron deficiency regenerative or nonregenerate
Either
93
How are WBCs evaluated?
Under a microscope
94
What are the 3 granulocytes?
Neutrophils Eosinophils Basophils
95
What is a synonym to leukocytes?
WBC
96
What are lymphocytes?
T and B cells
97
What are the characteristics of a neutrophil?
Granulocyte Smaller than a monocyte Larger than a lymphocyte Multiple lobes
98
What are neutrophils called in birds, reptiles, rabbits, and Guinea pigs due to their reddish granules?
Heterophobia
99
What is the function of neutrophils?
Phagocytosis and killing bacteria (inflammation)
100
What is the definition of a left shift?
An increase in band neutrophils
101
When would banded neutrophils increase?
During inflammation
102
What is eosinophil morphology?
Larger than neutrophil Bright pink granules
103
What is the function of eosinophils?
Granule released are cytotoxic to parasites and tumor cells Increase with worms wheezes and weird diseases
104
What do basophils look like?
Poorly segmented, ribbon-like nucleus, dark purple granules
105
What is the function of basophils?
Defend against helminths, histamine release
106
What is the morphology of monocytes?
Largest leukocyte Kidney bean appearance Contains vacuoles
107
What is the function of monocytes?
Leave blood to become macrophages Defend against bacteria, fungi, and Protozoa Process and present antigen to T lymphocytes
108
What are lymphocyte morphologies?
Larger than RBCs, smaller than neutrophils Very large nucleus
109
What is the function of B lymphocytes?
Humoral immunity Plasma cells secrete antibodies
110
What is the function of T lymphocytes?
Cell mediated immunity CD4 (activate B cells), CD8 (kill damaged cells), NK cells
111
What are the different pools in bone marrow?
Proliferating pool Maturation and storage pool
112
What are the different pools in blood?
Marginating pool Circulating pool
113
What is the function of the proliferating pool?
Can divide (myeloblasts, promyelocytes, myelocytes)
114
What is the function of the maturation / storage pools?
Allows for development and a reserve of neutrophils
115
What is the marginating granulocyte pool?
Cells adhere to vessel walls, ready to move to tissues
116
What is the circulating granulocyte pool?
What you sample when you sample blood (cells move back and forth between marginal granulocyte pool and circulating granulocyte pool)
117
What happens after neutrophil enter tissue?
Cannot recirculate, live for 1-4 days then die
118
Are lymphocytes long lived and continuously recirculate?
YES
119
What is toxic change in neutrophils?
Caused by intense granulopoiesis in bone marrow, usually caused by marked inflammation. Neutrophils have less time to mature so they retain som ribosomes and rough ER
120
What is a toxic change with blue inclusions of rough ER and is often the earliest indication of toxic change?
Dohle bodies
121
What are additional indication of toxic neutrophils?
Foaminess and larger nuclear lobes
122
What is the ladder of severity of toxic change?
Dohle Bodies
123
What is the prognosis when there is severe toxic change?
Poor
124
What is a synonym to regenerative left shift?
Appropriate left shift
125
What is the definition of a regenerative left shift?
Segs>bands
126
What is a degenerative left shift?
Bands>Segs
127
What might you see in the neutrophils of degenerative left shift?
Toxic change, myelocytes, and meta myelocytes
128
What are hypersegmented neutrophils?
5+ nuclear lobes
129
What are causes of hypersegmented neutrophils?
Corticosteroids, chronic inflammation, leukemia
130
What is it called when neutrophils have a failure to segment so cells resemble bands?
Pelger-Huet anomaly
131
Is Pelger-Huet Anomaly an issue?
No but dont misdiagnose as a left shift
132
What are the Big Bad Blue cells?
Blast cells
133
What are blast cells associated with?
Leukemia
134
During a leukocyte differential, what should you do if there are a lot of WBC present?
Count more cells to increase accuracy
135
During a leukocyte differential, how many cells should you count in the mono layer?
Count 100-200 cells
136
Can instruments distinguish nRBCs from WBCs?
No
137
What is the term for increased circulating WBCs?
Leukocytosis
138
What is the term for decreased circulating WBCs?
Leukopenia
139
What is the term for increased neutrophils, basophils, and basophils?
Neutrophilia, eosinophilia, and basophilia
140
What is the term for decreased neutrophils and eosinophils?
Neutropenia and eosinopenia
141
What is the term for increased lymphocytes and monocytes?
Lymphocytosis and monocytosis
142
What is the term for decreased lymphocytes and monocytes?
Lymphopenia and monopenia
143
What is the most numerous WBC in dogs and cats?
Neutrophils
144
What is the most numerous WBC in ruminants?
Lymphocytes
145
What is the most numerous WBC in horses?
Lymphocytes roughly equal to neutrophils
146
What are 2 reasons for a non-pathological leukocytosis?
Epinephrine (excitement, exercise) Corticosteroid (s=stress)
147
What are 2 reasons for a pathological leukocytosis?
Inflammation Leukemia
148
What is the term for decreased WBC?
Leukopenia
149
Is leukopenia always pathological?
YES
150
What does leukopenia indicate?
Increased utilization, decreased production
151
What are the 2 causes for non-pathological neutrophilic
Epinephrine (Excitement, Exercise) Corticosteroid (Stress neutrophilia)
152
What are the two pathological reasons for neutrophilia?
Inflammation/infection Neoplasia
153
What happens to the neutrophil pool when there is a epinephrine release?
Neutrophils shift from marginal pool to circulating pool
154
What is the most common species to show a physiological leukogram?
CATS (from blood draws)
155
What is stress neutrophilia? What is physiologic neutrophilia?
Stress = corticosteroids Physiologic = epinephrine
156
Where do the neutrophils in a stress neutrophilia come from?
The bone marrow storage pool (no increased production)
157
What type of neutrophil may show up in a stress neutrophilia?
Hypersegmented neutrophils
158
What is neutrophilia caused by inflammation or infection called?
Reactive neutrophilia
159
What does reactive neutrophilia do to pools?
Increased production and release from bone marrow, increased marginal pool, and increased migration into tissues
160
What will chronic inflammatory neutrophilia show up as?
Left shift is diminished, granulocyte hyperplasia (increased BM production) has restored the storage pool
161
What are some common causes of neutrophilia by inflammation?
Infectious agents (bacteria) Hemolysis Trauma IMHA Envenomation
162
What happens to neutrophil numbers during neoplasia?
Extreme neutrophilia/leukocytosis
163
What species has the largest neutrophil response?
Pigs
164
What is the word for “leukemia-like”, but not
Leukemoid
165
How do you know a leukemoid response isn’t leukemia?
Other evidence of inflammation (pyometra, pyothorax, etc) Lack of thrombocytopenia Improves over time
166
Is neutropenia (low neutrophils) always pathological?
YES
167
What does neutropenia indicate?
Over consumption of neutrophils (chronic) Peripheral destruction Increased margination
168
Why is neutropenia more common in cattle?
Smaller storage pools
169
Why is neutropenia associated with increased consumption
Severe inflammation overwhelms the BM’s ability to respond
170
What causes increased margination during neutropenia?
Endotoxemia (LPS produced by bacteria)
171
What is increased eosinophils called?
Eosinophilia
172
What causes eosinophilia?
Words (parasites), wheezes (allergies), and weird diseases
173
What 2 parasites can cause eosinophilia?
Ectoparasites Heartworms
174
What “wheezes” can cause eosinophilia
Allergies
175
What “weird diseases” can cause eosinophilia?
Addison’s disease Neoplasm (mast cell tumor)
176
What is most common cause of basophilia in dogs?
Hearworm
177
What affect does epinephrine have on lymphocytes?
Lymphocytosis (increased lymphocytes) from a shift to the circulating pool from the marginal pool
178
What are the 5 causes of Lymphocytosis?
Physiological (epinephrine) Age Antigenic stimulation/inflammation Addison’s Disease Neoplasia
179
Why does age cause Lymphocytosis?
Higher lymphocytes circulating in young animals
180
Why does antigenic stimulate cause Lymphocytosis?
Post vaccination Fighting infection
181
Why does Addison’s disease cause Lymphocytosis?
Decreased glucocorticoids normally inhibit lymphocyte production *** Always think Addison’s disease in a sick dog with Lymphocytosis because stress should cause lymphopenia
182
What is the most often cause of lymphopenia?
Stress leukogram! (Also Cushings) VERY IMPORTANT
183
What is LEMN?
Low Lymphocytes and eosinophils More monocytes and neutrophils ****************************
184
What are the 3 most common leukogram patterns?
Physiologic leukogram (epinephrine) Stress leukogram (corticosteroids) Inflammatory leukogram
185
What can acute inflammation in a cow cause?
Neutropenia and degenerative left shift due to small BM reserve of mature neutrophils
186
Why should a physiologic leukogram not have a left shift?
No increased release of neutrophils, just shifting from marginal pool to circulating pool so no bands
187
What is increased in a physiologic leukogram?
Neutrophilia Lymphocytosis
188
What happens in an inflammatory leukogram early?
Leukopenia due to migration from marginal pools into tissues
189
What happens in an inflammatory leukogram later?
Granulocytic hyperplasia (increased production of leukocytes) resulting in neutrophilia
190
What is hemostasis?
Coagulating “clotting”
191
What does deficient coagulation result in?
Hemorrhage
192
What does excessive coagulation result in?
Thrombosis
193
What doe endothelial cells produce during vascular damage?
von Willebrand factor(vWf) Tissue factor Plasminogen activator inhibitors
194
What is a platelet’s morphology?
Clear, membrane bound fragments of cytoplasm without a nucleus
195
What is the function of platelets?
Hemostasis - form a plug
196
What is the equivalent of platelets in birds and reptiles?
Thrombocytes
197
What is the con Willebran factor receptor?
Glycoprotein Ib (GPIb)
198
What is the fibrinogen receptor?
Glycoprotein IIB/IIIa (GP11b/111a)
199
What is the purpose of GPIb
Binds to the subendothelium initially
200
What is the purpose of GPiib/iiia?
Binds platelets to fibrinogen
201
How are platelets produced?
Anucleat fragments that are produced by a megakaryocyte
202
What’s the first thing that happens during vascular damage?
Vasocontriction - brief/transient; slows blood flow
203
What happens after vasocontriction during vascular damage?
Primary hemostasis
204
You’re gonna be ok
205
What happens after primary hemostasis during vascular damage?
Secondary hemostasis
206
What is the last step during vascular damage?
Fibrinolysis
207
What are the 3 sites for bone marrow sampling in small animals?
Iliac crest Proximal femur Proximal humerus
208
Where do you sample bone marrow in a large animal?
Sternum
209
What size needle do you use for bone marrow collection?
16 or 18 gauge needle
210
What type of stylets do you use for bone marrow collection?
Rosenthal, Illinois sternal, or Jamshidi
211
What type of syringe do you use for BM collection?
EDTA or heparin
212
What’s difference between BW aspirate and BM core?
BM aspirate = cytology -better cellular detail BM core = histology -better architecture
213
What’s the first step of primary hemostasis?
Platelets bind to subendothelium through GB1b binding to van Willebrand factor
214
What happens in primary hemostasis after platelet adhesion?
Platelets change shape, activate, and release granule for recruitment
215
What is the final step in primary hemostasis?
Platelet plug formation
216
What is secondary hemostasis?
Stabilization of platelet plug
217
What is the MPV?
Mean platelet volume (average size of platelet
218
What is platelet evaluation?
Estimate number of platelets on slide
219
What 2 different tubes should be used to analyze platelet numbers?
Either EDTA or sodium citrate
220
What happens if there are clumps in the thrombogram?
Artificially decrease thrombocytes
221
What would a patient with platelets below 20-30 be at risk of?
Risk of spontaneous hemorrhaging
222
What’s the equation to estimate the platelets on a hemocytometer?
Multiple avatar on 100x field by 20 x 109/L
223
What is a decrease of macrothrombocytes called?
Macrothrombocytopenia
224
What breeds is macrothrombocytopenia common in?
Cavalier King Charles Spaniels
225
What is the only test of platelet function that is normally done in clinics?
BMBT: Buccal mucosal bleeding time
226
What is BMBT?
Small cut in buccal mucosa to evaluate time until bleeding stops
227
What is normal BMBT in dogs? Cats?
Dog: 1-5 min Cats: 1-3.5 min
228
What does an increased BMBT mean?
Decreased platelets OR platelet dysfunction
229
When should you perform a BMBT?
Platelet numbers are known but platelet function is questioned
230
Will disorders of secondary hemostasis affect BMBT times?
NO!!
231
What is asymptomatic thrombocytopenia?
Generally low platelet counts in health without causing spontaneous hemorrhage Tend to have high MPV (mean platelet volume) due to macro platelets
232
What is the most common disorder that affects primary hemostasis?
Thrombocytopenia
233
What are less common causes of impaired primary hemostasis?
Decreased impaired platelet function (von willebrand disease)
234
What are some 4 clinical signs of a primary hemostasis disorder?
Petechia (small red spots) Ecchymoses (large red spot) Spontaneous mucosal bleeding (epistaxis, gingival bleeding) Prolonged bleeding Epistaxis = nose bleed
235
What is the first step to evaluate primary hemostasis disorder?
Determine total platelet count
236
What is second step, after platelet numbers come back normal, to determine primary hemostasis disorder?
Determine platelet function (BMBT)
237
What does an increased MPV and macro platelets suggest?
Immature platelets due to platelet regeneration
238
What are 3 main causes of thrombocytopenia?
Consumption: Utilization during hemostasis Destruction: Immune mediated thrombocytopenia Decreased production: Damage to BM or megakaryocytes not produced
239
Does hemorrhage cause decreased platelet count?
No, blood loss doesn’t cause decreased platelet but they are consumed during hemostasis
240
What is a disease associated with consumption of platelets?
Disseminated intravascular coagulation: Uncontrolled coagulation throughout body
241
What is a disease associated with destruction of platelets?
Immune mediated thrombocytopenia (ITP)
242
What is ITP?
Immune mediated thrombocytopenia caused by body producing antibodies against platelets Equal to IMHA for RBCs
243
What animals have ITP more often
Dogs Cocker spaniels Females
244
What is Evan’s syndrome?
Concurrent IMHA and ITP
245
What happens in bone marrow during ITP?
Increased megakaryocytes in bone marrow aspirate
246
What are lab findings associated with decreased production leading to thrombocytopenia?
No macroplatelets in circulation Decreased megakaryocytes in BM
247
What are the cells in the BW that produce macroplatelets and thus platelets?
Megakaryocytes
248
What is von Willebrand disease?
Defective and/or deficient vWf
249
How do you test for decreased vWf?
Quantitative ELISA
250
What happens if NSAIDS and aspirin are given to a dog?
Inactivated platelets through blocking of thromboxane production. Thromboxane (TXA2) is needed to activate GPIIb/IIIa which binds fibrinogen and allows for aggregation
251
Is the effect of aspirin reversible?
No, lasts 7 days
252
Are the effects of NSAIDs reversible?
Yes
253
What are the two general causes of thrombocytosis?
Physiologic: Epinephrine induced Reactive: Secondary to inflammation
254
What causes physiologic thrombocytosis?
Release of epinephrine causes splenic contraction (production is not increased)
255
What is reactive thrombocytosis?
Increased production from increased megakaryocytes in BM. Often have increased MPV
256
What might be seen in platelet numbers with an iron deficiency?
Increased platelet production (unknown reason)
257
What is the “glue” that holds platelets together during hemostasis?
Fibrin
258
When is the fibrin formed in hemostasis?
Secondary hemostasis
259
What is the goal of secondary hemostasis?
Formation of cross-linked fibrin
260
What is the coagulation factor needed in secondary hemostasis?
Thrombin (II)
261
What are the pathways of the coagulation cascade?
Intrinsic Extrinsic Common
262
What does the extrinsic pathway do?
Initiatives coagulation and forms a small amount of thrombin
263
What is the intrinsic pathway?
Amplifies coagulation and forms a large amount of thrombin
264
What are the factors of the intrinsic pathway?
12, 11, 9, 8
265
What are the factors of the extrinsic pathway?
Factor 7
266
What is the goal of the coagulation cascade?
To get a cross-linked fibrin
267
What are the different phases of fibrin?
Fibrinogen>fibrin>crosslinked fibrin
268
What converts fibrinogen to soluble fibrin?
Thrombin
269
What factor cross links fibrin to a non-soluble fibrin polymer needed for stability of clotting?
Factor 8a
270
What coagulation factors need vitamin K to become fully functional?
2, 7, 9, 10
271
What happens if there is a vitamin K deficiency
No vitamin K to help form crosslinked fibrin SEVERE hemorrhagic disorder
272
What is a necessary coagulation inhibitor?
Antithrombin III (ATIII)
273
What pathway does Antithrombin inhibit? What factors?
Intrinsic and common pathway Inhibits thrombin, 9a, 10a, and 11a
274
What activates Antithrombin (ATIII)?
Heparin
275
What is fibrinolysis?
Enzymatic lyses of fibrin clot Prevention of unchecked clotting
276
What is the fibinolytic (fibronlysis) enzyme?
Plasmin
277
What are the products from the breakdown of fibrin and fibrinogen?
Fibrin degradation products (FDP)
278
What are the products from the breakdown of cross-linked fibrin via plasmin?
D-Dimers
279
Where are the major abnormalities for bleeding disorders in secondary hemostasis?
Coagulation factors
280
What tube is used to determine coagulation cascade assays?
Sodium citrate tube for PT and aPTT
281
What tube can you not use for coagulation cascade assay? Why?
EDTA because EDTA binds Calcium irreversibly
282
Why can you use sodium citrate tubes for coagulation tests?
Sodium citrate is a reversible anticoagulant (not as effective as EDTA at binding Ca)
283
What test is used for intrinsic and common pathway?
Activated partial thromboplastin time (aPTT)
284
What test is used for extrinsic and common pathways?
Prothrombin time (PT)
285
What factors are in the common pothway?
X, V, II (prothrombin), fibrinogen (I)
286
Is aPTT and PT prolonged by thrombocytopenia?
NO
287
What factor has the shortest half-life of vitamin K dependent factors?
7
288
What causes increased FDPs and D dimers
DIC, hemorrhage, thrombosis (clots are being broken back down after they form)
289
What causes decreased clearance of FDPs and D-dimers?
Liver disease / failure
290
What does a normal coagulation panel measure?
PT APTT
291
What is thromboelastography (TEG)
Detects hypercoagulability
292
What are two reasons secondary hemostasis (coagulation cascade) would be abnormal?
Abnormal structure Decreased coagulation factors
293
What are clinical signs of secondary hemostatic disorders?
Hematomas - very common Hemoabdomen / hemothorax Bleeding initially stops (primary plug) then starts again
294
What is hemophilia?
Bleeding disorder due to an inherited deficiency of a clotting factor
295
What is inherited deficiency of clotting factor 8-12
Hemophilia A = factor VIII Hemophilia B = factor IX Hemophilia C = factor XI Factor XII deficiency
296
What hemophilia types have severe hemorrhaging issues?
Hemophilia A and B
297
What is factor I?
Fibrinogen
298
What is more common in secondary hemostasis disorders, development of a disorder or inherited disorder?
Inherited disorder
299
What factors would a vitamin K impair?
Factors II, VII, IX, and X
300
What are 3 reasons for a vitamin K deficiency?
Decreased production Malabsorption Vitamin K antagonism
301
What are vitamin K antagonists?
Anticoagulants like moldy sweet clover in cows and rodenticides (Warfarin)
302
Why is PT affected most in a vitamin K deficiency?
Because PT is affected first and worst because Factor VII has shortest half life!
303
What would liver disease do to PT and aPTT?
Prolong both because the liver produces most coagulation factors including fibrinogen
304
What is a mixed hemostatic disorder?
Bleeding disorder with abnormalities in primary hemostasis, secondary hemostasis, and fibrinolysis
305
What is the most common mixed hemostatic disorder?
Disseminated Intravascular Coagulation (DIC)
306
What is thrombosis?
Widespread formation of clots
307
What is DIC?
Consumption of coagulation proteins, antithrombotic proteins, and platelets, often enhanced fibrinolysis
308
What is DIC caused by?
ALWAYS secondary to another pathology
309
What diseases cause DIC?
Infection/sepsis Heart worm Heat stroke GDV
310
What causes DIC in horses and ruminants?
Endotoxemia or sepsis
311
What poikilocyte is common in DIC?
Schistocyte: Has to squeeze through clots
312
What are top differential that all need to happen together to suspect DIC?
Prolonged PT Prolonged aPTT Thrombocytopenia
313
How do you treat DIC?
Treat primary disease
314
What 3 things should be found in BW?
Fat, iron, and hematopoietic tissue
315
What is an ME ratio?
Myeloid to (nucleated) erythroid cells
316
What is a normal M:E ratio?
1-2
317
What is myeloid hyperplasia?
Myeloid is WBC so Myeloid hyperplasia in neutropenia situations
318
What does PIMA stand for?
Precursors-targeted immune mediated anemia AKA nonregenerative IMHA
319
What does PIMA do?
Auto immune attack of red blood cell precursors IMHA is attack on mature red blood cells
320
What 3 zones are in the adrenal gland?
Zone glomerulosa Zona Fasciculata Zona reticularis
321
What does the Zona glomerulosa produce?
Mineralcorticoids
322
What does the Zona fasciculata produce?
Glucocorticoids
323
What does the Zona reticularis produce?
Androgens
324
What does the medulla produce?
Catecholamines
325
What is an example of glucocorticoids? And function?
Cortisol Related to carbs and protein metabolism
326
What is an example of mineralcorticoids and what is its function?
Aldosterone Related to electrolyte and water metabolism
327
What are androgens?
Sex hormones
328
Which glucocorticoid has the lowest activity?
Corticosterone
329
What is clotting factor II?
Prothrombin