Test on Hematology Flashcards

Unlock all answers in this set

Unlock answers
question
What type of tissue is blood?
answer
connective
question
What are the three main functions of blood?
answer
transportation, regulation, protection
question
What are the protection factors of blood?
answer
WBCs and clotting factor
question
What hormone in males stimulates erythropoesis? (this explains why males have a higher hematocrit than females)
answer
testosterone
question
What is not included in the formed elements of blood?
answer
plasma
question
What is contained in the buffy coat?
answer
WBCs and platelets
question
What is the hematocrit?
answer
% of total blood volume occupied by RBCs
question
The following does what to the buffy coat layer: infection, inflammation, dehydration, cancer, leukemia?
answer
increases buffy coat layer
question
Where do microfilaria occur in centrifuge tube of blood?
answer
above buffy coat
question
What constitutes plasma?
answer
mostly water, but also plasma proteins
question
What is the function of plasma proteins?
answer
maintain water balance between intra- and extracellular fluid components via oncotic pressure
question
Where are plasma proteins derived from?
answer
liver (most) and WBCs
question
What plasma proteins are derived from WBCs?
answer
gamma globulins
question
What plasma protein transports lipids?
answer
albumins
question
What plasma protein is involved with clotting?
answer
fibrinogen
question
As plasma protein concentration is relatively stable, what is the usual concentration in 100ml of fluid?
answer
7g
question
During inflammation or an animal bleeding, what happens to PCV and [PP]?
answer
PCV is normal (slightly reduced because of increased protein and same volume of blood) and PP is increased (because trying to make more clotting factors)
question
If an animal is dehydrated, what happens to the PCV and [PP]?
answer
Both increased (because there is less water available and therefore concentrations of both increase)
question
In what instance will [PP] be decreased?
answer
end-stage liver disease (because liver no longer producing plasma proteins)
question
All formed blood elements originate from what?
answer
pluri-potent stem cells
question
What are the two stem lines produced by pluripotent stem cells?
answer
myeloid and lymphoid
question
What do myeloid stem cells differentiate into?
answer
RBCs, platelets, monocytes, granulocytes
question
What do lymphoid stem cells differentiate into?
answer
B and T lymphocytes
question
Where are the major sites of erythropoesis in adults?
answer
flat bones
question
Where does hemopoeisis occur in fetuses?
answer
spleen, liver, thymus, yolk sac, lymph nodes, red bone marrow, lymphoid tissue
question
Where does hemopoeisis of adults occur?
answer
red bone marrow and lymphoid tissue
question
What is the significance of CSFs (colony stimulating factors)?
answer
Promote hemopoeisis
question
What is hemopoeisis?
answer
blood cell replacement (not just RBCs)
question
Where is erythropoietin formed?
answer
kidney
question
Where is thrombopoietin formed?
answer
liver
question
What general percentage of body weight is used to determine the volume of blood in an animal?
answer
7%
question
True or False: Cats have a higher than normal blood volume and dogs have a lower than normal.
answer
False (switched)
question
What type of horse has a higher than normal blood volume compared to average?
answer
warm-blooded horses
question
What is the volume of blood in a cold-blooded stallion weighing 700kg?
answer
49L (700kg x 7/100 = 49 L)
question
How much blood can safely be withdrawn from a patient? Healthy donor?
answer
1% BW; 2% BW
question
When performing fluid replacement therapy, how much can safely be infused into severely dehydrated animal?
answer
7% BW over an hour (next 24 hours, infuse another 7%)
question
What is erythron?
answer
RBCs and precursors
question
What are circulating corpuscles which contain oxygen carrying hemoglobin?
answer
erythrocytes
question
What is the main function of RBCs?
answer
gas exchange
question
What are characteristics of RBCs that are measured in mammals to determine healthiness?
answer
shape, size, concentration, content, metabolism
question
A nearly saturated solution of hemoglobin = what percentage of RBC?
answer
33%
question
Compared to mammal RBCs, what is different about reptiles/amphibians/birds RBCs?
answer
nucleated, larger, oval, non-functional mitochondria
question
What is different about camelid RBCs?
answer
oval in shape
question
What is the normal shape of mammal RBCs?
answer
round
question
Where are RBCs produced in bony fish?
answer
spleen and liver
question
Where are RBCs produced in cartilaginous fish?
answer
within circulation
question
What animal has no RBCs at all?!
answer
Antarctic Icefish
question
What is significant about the repair process of RBCs?
answer
does not exist
question
How long do RBCs survive on average?
answer
4-5 months
question
In health and throughout every day life, approximately what percentage of RBCs die/are removed and have to be replaced?
answer
1%
question
For RBCs with a shorter lifespan, what changes about the percentage of RBCs that die and are replaced per day?
answer
increases
question
What causes damaged RBCs to be recognized as foreign bodies?
answer
antigenic groups
question
Where do damaged RBCs most often rupture (what organ)?
answer
spleen
question
Where is present in the spleen that allows RBCs to be recycled and absolved?
answer
macrophages
question
What system allows the selective removal of damaged RBCs in spleen, liver, bone marrow?
answer
mononuclear-phagocytic system
question
What is the recycled globin from RBCs used for?
answer
protein synthesis
question
What (after iron removal) is converted to bilirubin by macrophages during RBC breakdown?
answer
protoporphyrin
question
What happens to iron after recycling by macrophages performing RBC breakdown?
answer
binds to plasma protein to form transferrin
question
What binds with erythroblastic receptors to release iron into blast cells for hemoglobin synthesis?
answer
transferrin
question
When iron is released into the liver, it binds to an intracellular protein to form what?
answer
ferritin
question
What is the iron-transport form?
answer
transferrin
question
What is the iron-storage form?
answer
ferritin
question
What happens if ferritin stores are full?
answer
stored as hemosiderin in liver, pancreas, heart, can lead to toxic liver damage
question
What is the disease associated with hemosiderin (nearly insoluble)?
answer
hemosiderosis (iron-storage disease in birds/reptiles)
question
What birds suffer most often from iron-storage disease (especially in captivity)?
answer
toucans
question
Can an animal recover from hemosiderosis?
answer
Not usually (can bleed animal to help)
question
What controls erythropoeisis?
answer
tissue oxygenation
question
What are immature RBCs?
answer
reticulocytes
question
What are the precursors of reticulocytes?
answer
rubriblast
question
How long does it take to get from stem cell to reticulocyte?
answer
4-5 days
question
How long does it take for a reticulocyte to mature into a erythrocyte?
answer
1-2 days
question
What is the normal reticulocyte count in blood?
answer
1-2%
question
In what animals are there no reticulocytes when healthy?
answer
horses and ruminants
question
Erythropoeisis requires adequate supplies of what?
answer
iron, folic acid, Vit B (2,6,12)
question
Can a reticulocyte make hemoglobin?
answer
No (happens when maturing before this stage)
question
What are ways to strongly stimulate erythropoeisis?
answer
blood loss, increased elevation
question
When erythropoeisis is strongly stimulated, what happens to the number of reticulocytes? What is this called?
answer
increases; reticulocytosis
question
In dogs, what is the percentage of reticulocytes during reticulocytosis?
answer
25%
question
Full replacement of RBCs after a challenge takes approximately how many days?
answer
14
question
Which are larger: RBC or reticulocyte? Why?
answer
reticulocyte because it contains remnants of nucleus
question
In extreme cases of blood loss and reticulocytosis, what can be seen in blood and can turn the buffy coat pink?
answer
RBC precursors (metarubricytes, rubricytes, rubriblasts)
question
Can immature precursos of RBCs participate in oxygen-carrying?
answer
Yes (still making hemoglobin, but there is enough to carry and deliver oxygen!)
question
True or False: horses do not show reticulocytosis.
answer
true
question
True or false: ruminants show mild responses of reticulocytosis.
answer
true
question
What kind of reticulocytes are we looking for in a blood smear (especially in cats)?
answer
aggregate (lots of granules)
question
What are the three parameters measured with erythron evaluation?
answer
hematocrit, RBC count, hemoglobin content
question
How do you determine Hb content?
answer
by color (darker=more, lighter=less)
question
What is the difference between hematocrit and RBC count?
answer
hematocrit is % of RBCs present in whole blood; RBC count is number of RBCs in whole blood
question
What is the general value of Hb content?
answer
12-15g Hb/dL blood
question
What three primary values are used to calculate RBC parameters?
answer
hematocrit, RBC count, Hb content
question
What describes the volume of one erythrocyte?
answer
MCV (mean corpuscular volume in femtoliter)
question
What describes the hemoglobin content in a deciliter of RBCs?
answer
MCHC (mean corpuscular hemoglobin concentration in %)
question
What can cause a microcytic evaluation of MCV?
answer
iron deficiency
question
What is a normal MCV called?
answer
normocytic
question
What is a smaller than normal MCV called?
answer
microcytic
question
What is a larger than normal MCV called?
answer
macrocytic
question
What causes macroctic evaluations of MCV?
answer
immature RBC presence
question
What is a normal MCHC called?
answer
normochromic
question
What is a low MCHC called?
answer
hypochromic
question
What is a high MCHC called?
answer
hyperchromic
question
What is a normochromic MCHC value?
answer
33%
question
What can cause hypochromic MCHCs?
answer
iron deficiency, immature RBCs
question
What can cause hyperchromic MCHCs?
answer
hemolytic sample
question
What is the deficiency of oxygen carrying capacity?
answer
anemia
question
What are the classifications of anemia based on causes?
answer
hemorrhagic, hemolytic, dsyhemopoeitic
question
Extensive blood loss is what type of anemia?
answer
hemorrhagic
question
Ruptured RBCs is what type of anemia?
answer
hemolytic
question
Malfunction with the production of RBCs is what type of anemia?
answer
dyshemopoeitic
question
What are the classifications of anemia based on bone marrow response?
answer
regenerative, non-regenerative
question
What type of anemia involves the animal compensating for deficiency by producing more RBCs?
answer
regenerative
question
What type of anemia involves the animal having normocytic and normochromic evaluations?
answer
non-regenerative
question
How can you determine if an animal is in regenerative anemia?
answer
RBCs will be different sizes
question
If an animal suffers from acute blood loss, what hormones come into effect in the kidney?
answer
aldosterone and ADH
question
How long does it take for the body to replace fluids lost in a hemorrhagic anemia?
answer
2 days
question
Directly after hemorrhage, what will PCV and [PP] show?
answer
normal results
question
A few days after hemorrhage, what will PCV, [PP], MCV, MCHC, and Hb content show?
answer
decreased PCV, Hb content, and [PP] MCV and MCHC will be normal
question
After a hemorrhage, when does erythropoeisis begin?
answer
immediately after accident
question
After a hemorrhage, how long does it take for the MCV to show macrocytic values? Why?
answer
~3 days; takes that long for precursors to mature into reticulocytes
question
What are the parameters in hemolytic anemia?
answer
normocytic, hyperchromic, regenerative
question
What type of anemia involves something being wrong at the level of hemopoeisis?
answer
dyshemopoeitic anemia
question
In dyshemopoeitic anemia due to nutritional deficiencies where cells cannot produce enough Hb and keep on dividing, what are the parameters?
answer
non-regenerative, microcytic, hypochromic
question
What is the most common type of dyshemopoeitic anemia?
answer
anemia of chronic disorders
question
What are the parameters for dyshemopoeitic anemia due to chronic disorders like cancer?
answer
normocytic, normochromic, non-regenerative
question
True or False: Hemorrhagic and hemolytic anemias can become chronic disorders and lead to exhaustion of iron stores after long stimulation and eventually become non-regenerative anemias.
answer
True
question
What is polycythemia?
answer
increase in RBC numbers
question
Primary polycythemia is a rare disorder. What is it and it what animals is it normal in?
answer
uncontrolled RBC production; normal in sight hounds
question
What is secondary polycythemia?
answer
increase in RBC numbers due to oxygen deficiency from underlying cause (cancer, high altitudes, lung disease)
question
What is transient polycythemia and it what animals is it seen in?
answer
Spleen contraction due to excitement and exercise which releases more mature RBCs and increases PCV; seen in horses, cats, sight hounds
question
What is not a true polycythemia, but is caused by dehydration and therefore all blood components become more concentrated?
answer
relative polycythemia
question
Do animals have blood groups?
answer
yes
question
What kind of blood system is present in cats?
answer
A - B system
question
In North America, almost 99% DSH cats are what blood type?
answer
A
question
In Europe, what percentage of DSH cats are type A?
answer
50%
question
In purebred cats like the persian, what is the blood type ratio?
answer
1:1 (50% A and 50% B)
question
What are the highly antigenic blood types in dogs?
answer
1.1, 1.2, 7
question
What animals carry natural antibodies in their blood circulating? What significance is this?
answer
humans and cats; react very quickly to wrong blood type
question
How can giving the wrong blood type to a cat lead to acute renal failure?
answer
agglutination of invading RBCs, blockage of capillaries, shcok, precipitation of excess Hb after rupture of RBCs, renal blockage, renal failure
question
If a dog is given the wrong blood type for the first time, what happens? Second time?
answer
mild, delayed reaction; full blown immune response
question
What is the determination of the RBC antigens present in an individual?
answer
blood typing
question
What is the ideal donor dog?
answer
one without antigens 1.1, 1.2, and 7
question
When cross-matching blood, how can you determine if there will be a major reaction?
answer
expose donor's RBCs to recipient's plasma and observe for agglutition
question
When cross-matching blood, how can you determine if there will be a minor reaction?
answer
expose recipient's RBCs to donor's plasma and observe for agglutition
question
If there is a minor reaction when cross matching blood types, what can be done to allow the blood to be used to avoid a minor reaction?
answer
remove plasma and replace with saline
question
What is hemostasis?
answer
sequence of responses that stops bleeding
question
What are three ways to describe hemostasis?
answer
fast, localized, carefully controlled
question
What are the five steps of hemostasis?
answer
vascular spasm, platelet plug formation (primary hemostasis), blood clot formation (secondary hemostasis), healing, clot removal (fibrinolysis)
question
What is primary hemostasis?
answer
platelet plug formation
question
What is secondary hemostasis?
answer
blood clot formation
question
What is fibrinolysis?
answer
clot removal
question
What is the shape of platelets?
answer
flat, round to oval, enucleate
question
What is different about the platelets of birds and reptiles compared to mammals?
answer
nucleated
question
What is different about the size of platelets when compared to RBCs?
answer
about half the size
question
What is the normal concentration of platelets in a microliter of blood?
answer
150,000-300,000 platelets per microliter
question
What is the half-life of platelets?
answer
10 days
question
Where are platelets derived from?
answer
bone marrow megacaryocytes (pluripotent -> myeloid -> CFU ->megakaryoblast -> megakaryocyte ->platelets)
question
What stimulates the production of platelets and is produced by the liver?
answer
thrombopoietin
question
What are the functions of platelets (four)?
answer
release of chemicals that promote vasospasm, formation of platelet plugs, release of factors that promote coagulation, healing processes
question
When does vasospasm occur after vessel injury?
answer
immediately
question
What causes vasospasm immediately after vessel injury?
answer
endothelin release from damaged cells
question
What causes vasospasm later after vessel injury?
answer
thromboxane A2 and serotonin from platelets
question
What is primary hemostasis?
answer
platelet plug formation
question
What is released by damaged endothelial cells?
answer
vWF (von Willebrand Factor)
question
When endothelial and plasma vWF bind to damaged cell membranes and collagen fibers, what binds to the now expressed receptor sites?
answer
platelets
question
What happens when platelets bind to receptor sites at areas of damaged tissues?
answer
send out pseudopodia to interact with other platelets
question
What do platelets release once bound to receptor sites of damaged tissue to stimulate vasospasm?
answer
serotonin and thromboxane a2
question
What is released from platelets to attract more?
answer
ADP and thromboxane a2
question
What is released from platelets to promote adhesion?
answer
ADP and fibronectin
question
For clotting to happen, what mineral must be present along with platelet factors?
answer
calcium
question
For a minor injury, how long does it take for a loose platelet plug to seal injury site?
answer
1-2 minutes
question
With larger injuries, the clotting cascade is activated concurrently to stabilize the platelet plug with what?
answer
fibrin strands
question
What is secondary hemostasis?
answer
clot formation (coagulation)
question
Clot formation involves cascades of chemical reactions leading to the formation of strong ___ threads within the platelet plug, which gives it more strength.
answer
fibrin
question
What are the two pathways which lead to the formation of a prothrombin-activator complex?
answer
extrinsic and intrinsic
question
What converts fibrinogen to fibrin?
answer
thrombin
question
What converts prothrombin to thrombin?
answer
prothrombin-activator complex
question
Which of the coagulation pathways is tissue based?
answer
extrinsic
question
Which of the coagulation pathways is plasma based?
answer
intrinsic
question
In the intrinsic pathway, what activates plasma factor XII which leads to the formation of the prothrombin activator complex?
answer
negative charges on outside of cell
question
Which coagulation pathway is faster?
answer
extrinsic
question
Which coagulation pathway is not present in birds?
answer
intrinsic
question
What is a plasma protein from the liver that is from the globulin family and attaches itself to activated platelets to form the prothrombin activator complex?
answer
prothrombin
question
What is the cofactor of prothrombin?
answer
vit K
question
What encourages the intrinsic/extrinsic pathways of blood coagulation and stimulates fibrin formation?
answer
thrombin
question
How long after injury does it take for bleeding to be stopped by coagulation?
answer
3-6 minutes
question
How long does it take for the clot to retract from a minor injury?
answer
30 minutes
question
The blood fluid that remains after hemostasis is called what?
answer
serum
question
Serum is plasma minus what?
answer
clotting factors
question
Fibrin provides scaffolding for what cells to promote wound healing?
answer
fibroblasts
question
What are fibroblasts stimulated by?
answer
platelet derived endothelial growth factor
question
What is fibrinolysis?
answer
clot removal
question
1-2 days after clot formation, what does the injured tissue and endothelium release very slowly which activates a proteolytic enzyme meant to denature the clot?
answer
t-PA (tissue-plasminogen activator)
question
What does t-PA do?
answer
changes plasminogen to plasmin
question
What does plasmin do?
answer
hydrolyses fibrin fibers and clotting factors
question
What is created by plasmin?
answer
FDPs (fibrin degradation products)
question
What removes FDPs?
answer
macrophages
question
What factors prevent unnecessary hemostasis?
answer
smoothness of endothelial cells, prostacyclin (secreted by endothelial cells) and Nitric Oxide which inhibit adhesion
question
What prevents excessive clot formation?
answer
fibrin binds thrombin to limit positive feedback, anti-thrombin III deactivates clotting factors, heparin from amst cells combins with anti-thrombin III to augment effectiveness.
question
What is used for in vitro anticoagulation?
answer
calcium binding agents, heparin
question
What is used for in vivo anticoagulation?
answer
heparin, vit K antagonists, NSAIDs
question
Why is it important that calcium binding agents are used for anticoagulants?
answer
Because prevents calcium from binding to platelet factors to avoid coagulation
question
Can we use calcium binding agents in vivo?
answer
NO - fatal to animal to remove calcium from body
question
Why can we use Vitamin K antagonists in vivo as anticoagulants?
answer
Cofactor of prothrombin, prevents coagulation
question
If a dog is suspected to have a bleeding disorder, what can be used to determine whether issue is initially with platelets?
answer
platelet count
question
How do you test whether issue is with von Willebrand factor and platelets?
answer
Muscosal bleeding time
question
What is the muscosal bleeding time test?
answer
Make minute incision into skin or mucosa and stop time when bleeding stops (want to be 1-5 minutes)
question
What test for determining extent of bleeding disorders involves measuring clot formation in citrated plasma after addition of tissue factor, platelet factors, and calcium?
answer
OSPT (one stage prothrombin time)
question
What does the OSPT test measure?
answer
extrinsic and common pathway of clotting mechanism
question
What three things are necessary to add when performing the OSPT and why?
answer
Calcium (because citrate removed calcium), platelet factors (to rule out whether they are interferring with tests), and tissue factors (because clean venipuncture would mean none is brought into sample)
question
What is the expected time of OSPT?
answer
<10 seconds
question
IF the OSPT test is prolonged, what factors are possibly messed up?
answer
plasma factors, fibrinogen, and thrombin
question
What test involves measuring clot formation after clean venipuncture in citrated plasma and addition of contact activator, platelet factors, and calcium?
answer
APTT (activated partial thromboplastin time)
question
If OSPT = prolonged, APTT = normal, where is issue?
answer
extrinsic pathway plasma factors
question
If APTT = prolonged, OSPT = normal, where is issue?
answer
intrinsic pathway plasma factors
question
If APTT and OSPT = normal, where is issue?
answer
common pathway (fibrinogen and thrombin)
question
What is thrombocytopenia?
answer
decreased production or increased destruction or consumption of thrombin
question
What are coagulopathies?
answer
bleeding disorders
question
What is the most common bleeding disorder in animals due to genetic lack/insufficiency in vWF where platelets fail to adhere to injury sites?
answer
von Willebrand's Disease
question
What breed of dog most often has von Willebrand Disease with 70% prevalence?
answer
Dobermans
question
What is a vitamin K antagonist in rat poisons which impairs liver synthesis of several clotting factors?
answer
coumarin
question
What are genetic deficiencies in a clotting factor?
answer
hemophilias
question
What is clotting in an unbroken blood vessel (due to stasis, atherosclerosis, trauma, parasites, tumors, etc)?
answer
thrombosis
question
What thrombosis in cats is due to myocardial diseases where clot becomes lodged at caudal trifurcation where aorta diverges into iliac arteries?
answer
saddle thrombus (aortic thromboembolism)
Get an explanation on any task
Get unstuck with the help of our AI assistant in seconds
New